Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30TechnologyMODELING, ANALYSIS AND OPERATION OF WIND DRIVEN DFIG UNDER UNBALANCE NETWORK VOLTAGE CONDITIONS: A REVIEW
English0108Debirupa HoreEnglish Runumi SarmaEnglishThis paper investigates the operation of wind-driven DFIG under unbalance Voltage or unsymmetrical fault condition. According to grid codes worldwide, the wind-driven DFIG are required to supply reactive power during and after the fault. It has been observed that the conventional vector control method used for control of DFIG does not work well during fault conditions. To reduce the oscillations in electromagnetic torque and Stator Active power and to maintain constant DC link Voltage a new control strategy has to be presented. Sequential decomposition of positive and negative sequence currents and controlling it with PI plus proportional Resonant controller is adopted both on Rotor side and grid side converter.The paper presents a development in methodologies for controlling wind driven DFIG during fault ride conditions. In recent year improved control strategy using different Artificial Intelligence-based controllers are used to control the RSC and GSC without sequence decomposition.
EnglishWind turbines, Rotor side converter, Doubly fed induction generator, Low-voltage ride-through INTRODUCTION
Over the last few years, doubly fed induction generators (DFIGs) have dominated the largest world market share of wind turbines (WTs), as an alternative concept to conventional variable speed generators. A DFIG consists of a wound rotor induction generator with its stator windings directly connected to the grid and its rotor windings connected to the grid via an arrangement of two ac/dc backto-back converters. As the converters are sized for only the one third of the rated power of the turbine, this topology accomplishes a cost-effective, decoupled control of the active and reactive power. However, DFIGs present a major drawback concerning their operation during grid faults. The voltage drop at the stator windings, due to grid faults, results in a sudden change in the stator flux of the DFIG, which finally leads to an over current to the rotor windings, due to the magnetic coupling. This over current may cause severe damage to the semiconductors of the rotor side converter and large fluctuations of the dc-link voltage. When DFIGs started being used in WTs, the penetration of WTs to the power system was relatively low, so their control concerning faults focused on the protection of the DFIGs themselves and no special actions were taken in order to provide the DFIGs with the capability of contributing to network support. Under this concept, in order to protect the generator, its rotor windings were protected with a crowbar circuit. This device consists of a bank of resistors, which is connected to the rotor windings through power electronic devices. When a fault is detected, the rotor windings are connected to the crowbar resistors, whereas the rotor-side converter is temporary disabled. Thus, the short-circuit current flows through the crowbar instead of the rotor-side converter. With this solution, the machine is effectively protected, but due to the fact that the blocking of the rotor-side converter leads to the partial loss of power control during the crowbar action, large transients are generated after the fault, which may lead to the disconnection of the machines from the grid. In addition, during the activation of the crowbar, the DFIG is converted to a conventional squirrel-cage induction generator, absorbing a large amount of reactive power from the grid. Nowadays, due to the fact that WTs represent a significant part of the total generation in electrical systems, system operators worldwide have revised their grid codes (GCs), making the requirements concerning the fault ride-through (FRT) capability of WTs more stringent. The majority of the GCs require that the WTs should provide low voltage ride-through (LVRT) capability for grid faults resulting in a 85% voltage drop or even more. This means that they should stay connected to the grid during and after grid faults, contributing to the system stability. Moreover, they should supply reactive power to the grid in order to support the voltage recovery. This requirement cannot be fulfilled by DFIGs protected with a conventional crowbar circuit, as they cannot generate reactive power during the activation of the crowbar. For this reason, researchers started addressing the issue of the FRT of the DFIGs from several other points of view. For instance, proposes an improved version of the crowbar circuit, eliminating the duration of the crowbar action. Reference investigates the application of a STATCOM to achieve the uninterrupted operation of a wind turbine equipped with a DFIG during grid faults. In a control strategy using a series grid-side converter is proposed. Although these last two arrangements are promising in some cases, the complexity and the additional cost impair their applicability. Other papers propose some methods for FRT without any auxiliary external devices . They show that if the DFIG controllers are suitably designed, it is possible to limit the rotor over current. Xiang et al. in propose a control strategy that orients the rotor current to counteract the dc and negative sequence components of stator flux linkage. Experimental results show that under certain circumstances, the rotor current is limited; therefore, the use of the crowbar can be avoided. However, this method has high dependence on the estimation of stator flux linkage and the exact knowledge of the parameters of the DFIG. In is proposed a flux linkage tracking-based control strategy, to suppress the fault rotor current. Its control objective is to keep the rotor flux linkage close to the stator flux linkage instead of maintaining a certain value accurately. In this way, there is no need to decouple the dc and negative sequence components, which means the control scheme does not depend on the exact knowledge of the system parameters. Although the proposed control method is promising, the paper could have studied a bigger voltage dip for the case of the three-phase fault, as it is imposed by international grid codes. In , Hu et al. propose the use of a virtual resistance in combination with demagnetization control to limit the rotor side over currents. This method manages to enlarge the control range in relation to the control method proposed in, but the drawbacks that were met in still cannot be avoided. The study described in suggests that a properly designed fuzzy controller (FC) presents a better performance in presence of variations of parameters and external disturbances than a traditional proportional integral (PI) controller. Comparative results between the two controllers showed that the FC manages to limit the generator currents during the fault, avoiding the use of the crowbars. However, it would be interesting to see which would be the response of this control system and what changes should possibly be done, for the case where the DFIG would be connected to a weaker bus, instead of an infinite bus. Reference proposes a control strategy based on genetic algorithms (GA) for the acquisition of the optimal gains of the PI controllers to the rotor-side converter of the DFIG. The GA fitness function is defined with the objective to reduce the over-current in the rotor circuit, in order to maintain the converter in operation during the fault period. Simulation results show that, in some cases, if the GA gain adjustment is used, the use of the crowbar protection-scheme can be avoided. However, in this work, no analytical information is given about the electrical grid connected to the DFIG. In addition, it is tested for a small voltage dip in relation to the voltage dip described in most grid codes. Papers propose some methods for FRT without any auxiliary external hardware for the case of asymmetrical grid faults. Based on the experience gained from the studies published so far, this paper tries to extend the concept of the protection of the DFIG without the use of additional hardware, in more demanding situations, such as the connection of a relatively weak electrical system with the DFIG in the case of a fault resulting in a bigger voltage dip, as it is required from the GCs. The proposed control scheme contributes to the optimal coordination of the two converters, aiming to attenuate the disturbances to the system caused by the fault and ensure system stability. In order to encounter the difficulties met due to the uncertainties of the system modeling and considering the nonlinearity of the system, the controllers were designed based on fuzzy logic (FL) and GAs, which are more efficient in such cases. By this concept, the over currents at the rotor windings and the dc side over voltages are effectively eliminated. In addition, the FRT requirement concerning the reactive power supply is fulfilled. In this point, it would be necessary to point out that many previous papers have tested their proposed systems using small scale test equipment that had a rotor voltage rating far too high, when compared with the megawatt range WT generators that have stator to rotor winding turns ratio around 2.5 to 3.
LITERATURE REVIEW
Year 2007 Wang, Lu Xu develops the dynamic model and control scheme for DFIG to improve the performance and Stability under unbalanced grid conditions. The modeling is done using both positive and negative sequence components using Stator Voltage orientation. Here the control Strategy for active, reactive powers and electromagnetic torque oscillations during unbalanced system network is presented. The system control is based on a positive sequence controller which controls average active and reactive Power and a negative sequence controller which minimizes torque or power oscillations. The proposed scheme works well under unbalance Voltage network.
Hu, He, Heng presents a unified positive and negative sequence dual dq dynamic model of wind turbine driven DFIG under unbalanced grid Voltage conditions using PWM Voltage source Converter(VSC).The modified control design for the grid side converter in the Stationary αß frames diminishes the amplitude of DC link Voltage ripples twice the grid frequency. On the rotor side converter two control strategies using PI controller improves the fault ride capability of the DFIG based wind power generation system during unbalanced network supply. A rotor current control scheme based on positive and negative synchronously rotating reference frame was proposed to provide precise control of rotor current. Xu and Wang present an analysis and control of DFIG based wind generation system under unbalanced network conditions. The system is modeled in positive and negative synchronous reference frame. It shows that conventional vector control of DFIG without considering network unbalance results in excessive oscillations on Stator active and reactive Power and electromagnetic torque and stator and rotor currents even with a small Stator Voltage unbalance. A rotor current control strategy based on positive and negative (dq) reference frames is used to provide precise control of rotor positive and negative sequence currents. On account of negative rotor current influence converter voltage /power ratings is increased. Here in this paper an effective control strategy is presented. Yusuf Yasa, Evren Isen Yilmaz Sozer , Erkan Mese, Hilmi Gurleyen in their Paper presents detailed analysis of doubly fed induction generator (DFIG) wind turbine electrical components during normal and unbalanced fault condition. Wind turbine components are individually modeled and then combined in a simulation process which is called coupled simulation. The coupled simulation results show that grid frequency oscillation occurs on q and d axis currents under one phase-ground fault condition. Experimental study has been done to show the effects of fault on rotor currents.
Year 2008 Hu, He in their paper presented a new concept and mathematical model of instantaneous active & reactive Power at different locations of VSC. To avoid the use of band trap or notched filter for decomposing the positive and negative sequence dq component of current and voltage a new scheme with multi frequency proportional resonant controller in the stationary αß frame is employed to improve the steady state and dynamic response under generalized unbalanced operation condition. The proposed control scheme is the stationary reference frame provides sufficiently steady state tracing capability for ac current and better transient response in compensation for wide range unbalanced operation conditions. By reducing oscillating terms or harmonics from DC link Voltage and stator powers the ratings of the capacitor and converters can be kept low. He Hu et al presents the analysis and modeling of DFIG based wind power generation system under unbalanced network voltage conditions. During unsymmetrical fault there is existence of negative sequence currents and Voltages. For this the system parameter gets disturbed. Here a new current control scheme consisting of Proportional Integral (PI) controller plus resonant compensator is presented which is in rotating reference frame and is able to provide an enhance current control for both rotor and grid side converters without decomposition of positive and negative sequence currents. Under unbalance or low stator voltage conditions the operation of wind driven DFIG must be taken care of by simultaneously removing the fluctuations in electromagnetic torque and output active power. For the RSC the main concern is to focus on limited voltage magnitude supplied with different modulation technique and for the GSC the most important issue is to maintain dc link Voltage constant.
Year 2009 He Hu presented a control strategy involving a proportional resonant controller tuned at grid frequency & implemented in the stator stationary reference frame without involving decomposition of the positive and negative sequence currents. The oscillation in electromagnetic torque, Stator active power, double the grid frequency is eliminated. Three selective control targets for GSC is developed to reduce the pulsations in stator active power. RSC is controlled to control the oscillations of the electromagnetic torque. Wang Xu Hu He et al presented a proportional integral plus multi frequency resonant current controller for grid connected voltage source converter under unbalance voltage conditions. The control scheme is implemented on positively synchronously rotating reference frame and composed of PI plus MFRC tuned at frequency of 2ws and 6ws respectively. The scheme works well under unbalance Voltage conditions by reducing active power oscillations and 5th, 7th order current harmonics elimination during supply voltage imbalances Yi Zhou, Paul Bauer, Jan A. Ferreira, Jan Pierik provides the benefits of variable speed operation costeffectively, and can control its active and reactive power independently. Crowbar protection is often adopted to protect the rotor-side voltage source converter (VSC) from transient over current during grid voltage dip. But under unbalanced grid voltage condition, the severe problems are not the transient over current, but the electric torque pulsation and dc voltage ripple in the back-toback VSCs. This paper develops dynamic models which investigates the behavior of DFIG during unbalanced grid voltage condition, and proposes new controllers in separated positive and negative sequence. Methods to separate positive and negative sequence components in real time are also developed, and their responses to unsymmetrical voltage dip are compared. It is seen that the “signal delay cancellation” is much faster than the “low-pass filter,” and is chosen in this study. Equations of instantaneous active p and reactive power q, and voltage equations of DFIG and grid VSC in positive dq and negative dq sequence are derived.
Jesús López, , Eugenio Gubía, , Eneko Olea, Josu Ruiz, and Luis Marroyo This paper deals with the grid fault ride-through capability of doubly fed induction generators. These machines are very sensitive to grid disturbances. To prevent the damages that voltage dips can cause on the converter, most machines are equipped nowadays with a crowbar that short circuits the rotor. However, during the crowbar activation, the rotor converter must be disconnected, hence the power generated with the turbine is no longer controlled. In doing so, the crowbar impedes the wind turbine from carrying out the voltage stabilization required by most new grid codes. This paper proposes a novel control strategy that notably reduces the crowbar activation time. As a result, the control of the turbine might shortly be resumed and the turbine can furthermore supply a reactive power fulfilling the newest grid regulations.
Year 2010 Van-Tung Phan and Hong-Hee Lee An enhanced control strategy for variable-speed unbalanced standalone doubly-fed induction generator-based wind energy conversion systems is proposed in this paper. The control scheme is applied to the rotor-side converter to eliminate stator voltage imbalance. The proposed current controller is developed based on the proportional-resonant regulator, which is implemented in the stator stationary reference frame. The resonant controller is tuned at the stator synchronous frequency to achieve zero steadystate errors in rotor currents without decomposing the positive and negative sequence components. The computational complexity of the proposed control algorithm is greatly simplified, and control performance is significantly improved. An enhanced control scheme using the PR controller for unbalanced stand-alone DFIG systems was investigated in this paper. The proposed current controller was implemented in the stator stationary reference frame for controlling positive and negative sequence components without the sequential decomposition of the measured rotor currents. Consequently, the desired control target, i.e., eliminating the negative sequence components in unbalanced stator voltages, was well achieved with the proposed control method. Comparative results between the proposed and the conventional PI controllers indicated the ability of the former to perform a more precise and adequate control of proposed Strategy
Francisco K. A. Lima, Alvaro Luna, Pedro Rodriguez, Edson H. Watanabe, and Frede Blaabjerg,
This paper presents a new control strategy for the rotor-side converter (RSC) of wind turbines (WTs) based on doubly fed induction generators (DFIG) that intends to improve its low-voltage ride through capability. The main objective of this work is to design an algorithm that would enable the system to control the initial over-currents that appear in the generator during voltage sags, which can damage the RSC, without tripping it. As a difference with classical solutions, based on the installation of crowbar circuits, this operation mode permits to keep the inverter connected to the generator, something that would permit the injection of power to the grid during the fault, as the new grid codes demand. This strategy is based on using the measured stator current values as the set point for the rotor current controller during the fault. As it has been demonstrated, in this way, it is possible to synthesize a current in the stator in opposition to the currents generated during the fault, preventing thus the stator/rotor windings from suffering over-currents, with no need of using crowbar circuits.
Year 2011 Xueqin Zheng Donghui Guo (2011) With the increasing of wind penetration in power systems, new grid codes require distributed energy resources to ride through temporary low voltage event and at the same time injecting reactive current into the grid. The purpose of this paper is to optimize control strategy and enhance the performances of the doubly fed induction generator wind power system by using the combination of doublevector-PWM control and the active crowbar in series with the stator windings. This control strategy can notably reduce the stator and rotor over-current and keep the dc bus voltage stable, which prevent the damages that voltage dips cause on the converter and power system. This paper dealt with low voltage ride through capability improvement in DFIG wind power system. An efficient control strategy was proposed. The proposed strategy is a combination of double-vector-PWM control strategy and active crowbars which are series with the stator windings for a DFIG system. The principles of the system operation and control strategy were described. The system performances during three-phase grid voltage dip was studied. The analysis and simulations results showed that the system can ride through under such a fault satisfactorily by maintaining the stability of the wind farm AC network and dc bus voltage, the output active and reactive power. The rotor and stator currents can considerably reduce at the instant of occurring and clearing the fault.
Sheng Hu, Xinchun Lin, Yong Kang, and Xudong Zou This paper presents a control strategy to improve the low-voltage ride-through capability of a doubly fed induction generator (DFIG); since the stator of a DFIG is directly connected to a grid, this sort of machine is very sensitive to grid disturbance. Grid voltage sag causes over-currents and over-voltages in rotor windings, which can damage the rotor-side converter (RSC). In order to protect the RSC, a classical solution based on installation of the so-called crowbar is adopted; however, as the DFIG absorbs reactive power from the grid, this type of solution deteriorates grid voltage sags and cannot meet the requirements of a new grid code. An improved control strategy which uses virtual resistance to limit rotor side over-currents is proposed in this paper, which can make a crowbar inactive and supply reactive power to fulfill the latest grid code requirement during voltage sags.
Year 2012
Mokryani, Siano et al presents a fuzzy logic based controller to increase fault ride through capability of variable speed wind turbine equipped with DFIG. The controller is designed in order to compensate Voltage ups and downs by regulating the active and reactive power generated by DFIG. Here the oscillations of stator active and reactive power are compensated simply by tunning the fuzzy controller without using any filter circuits. V. Suresh, D. J. V Prasad presents a mathematical model of a doubly fed induction generator (DFIG) in the positive synchronous reference frame under distorted grid voltage conditions with the help of fuzzy logic controller. The oscillations of the DFIG’s electromagnetic torque and the instantaneous stator active and r active powers are fully described when the grid voltage is harmonically distorted. Four alternative control targets are proposed to improve the system responses during grid harmonic distortions. A new rotor current control scheme implemented in the positive synchronous reference frame is developed. The control scheme consists Fuzzy logic controller and a resonant controller consequently, the fundamental and the fifth- and seventh-order components of rotor currents are directly regulated by the Fuzzy–R controller without sequential-component decompositions. Yan Yan , Meng Wang , Zhan-Feng Song and Chang-Liang Xia presents a novel control strategy is proposed in this paper for the rotor side converter (RSC) of doubly-fed induction generator (DFIG)-based wind power generation systems. It is supposed to enhance the low-voltage ride-through (LVRT) capability of DFIGs during great-level grid voltage dips. The strategy consists of a proportional-resonant (PR) controller and auxiliary PR controllers. The auxiliary controllers compensate the output voltage of the RSC in case of grid faults, thus limiting the rotor inrush current of DFIG and meeting the requirements of LVRT. Sequential-component decompositions of current are not required in the control system to improve the response of system. Since the resonant compensator is a double-side integrator, the auxiliary controllers can be simplified through coordinate transformation. With limited RSC voltage ratings, the rotor fault currents of specified frequencies are eliminated to a great extent. The controller performs well, even when the angular frequency detection is not accurate. Simulations have been presented under symmetric and asymmetric grid fault conditions to confirm the analysis and verify the proposed control method.
Year 2013
Zarei, Asaei et al presented a new control method for rotor side converter (RSC) and grid side converter (GSC) of doubly fed induction generator (DFIG) is proposed. A combined vector control and direct power control for RSC and direct current control for GSC have been introduced. The RSC directly controls the stator d-q axis currents (rotating at synchronous speed ws) by applying an optimal voltage vector from a switching table. Under the unbalanced and distorted grid voltage conditions, the new control strategy injects a pure sinusoidal and balanced stator and GSC currents without any need of extracting the negative sequence and 5th and 7th voltage harmonics. Only a modified phase locked loop (PLL) to extract the positive sequence of the fundamental phase angle, is added to this situation.
Zaijun Wu , Chanxia Zhu and Minqiang Hu presents an improved control strategy for both the rotor side converter (RSC) and grid side converter (GSC) of a doubly fed induction generator (DFIG)-based wind turbine (WT) system to enhance the low voltage ride through (LVRT) capability. Within the proposed control strategy, the RSC control introduces transient feed-forward compensation terms to mitigate the high frequency harmonic components and reduce the surge in the rotor currents. The proposed GSC control scheme also introduces a compensation term reflecting the instantaneous variation of the output power of the rotor side converter with consideration of the instantaneous power of grid filter impendence to keep the dc-link voltage nearly constant during the grid faults. To provide precise control, nonideal proportional resonant (PR) controllers for both the RSC and GSC current regulation are employed to further improve dynamic performance. Further DC link Voltage equation is modified by modifying the rotor power equation in terms of grid side parameter.
Xinyan Zhang, Xuan Cao, Weiqing Wang, Chao Yun presents in their paper the rotor short current of doubly-fed induction generator (DFIG) was limited by introducing a rotor side protection circuit. Second, the voltage of DC bus was limited by a DC energy absorb circuit. Third, STATCOM was used to increase the low level voltages of the wind farm. Simulation under MATLAB was studied and the corresponding results were given and discussed. The methods proposed in this paper can limit the rotor short current and the DC voltage of the DFIG WT to some degree, but the voltage support to the power system during the fault largely depend on the installation place of STATCOM. New FRT needs not only the WTs keep on grid but also can provide voltage support or generator reactive power to the power system.
Shuai Xiao, Geng YangHonglin Zhou, and Hua Geng,In For doubly fed induction generator (DFIG)- based wind energy conversion systems (WECSs), large electromotive force will be induced in the rotor circuit during grid faults. Without proper protection scheme, the rotor side of DFIG will suffer from over-currents, which may even destroy the rotor-side converter (RSC). To mitigate this problem, a new flux-linkage trackingbased low-voltage ride-through (LVRT) control strategy is proposed to suppress the short-circuit rotor current. Under the proposed control strategy, the rotor flux linkage is controlled to track a reduced fraction of the changing stator flux linkage by switching the control algorithm of RSC during grid faults.
Year 2014
Theodoros D. Vrionis, Xanthi I. Koutiva, and Nicholas. A. Vovos proposes a new computational intelligence- based control strategy, to enhance the low voltage ride-through capability of grid-connected wind turbines (WTs) with doubly fed induction generators (DFIGs). Grid codes world-wide require that WTs should supply reactive power to the grid during and after the fault, in order to support the grid voltage. The conventional crowbar-based systems that were initially applied in order to protect the rotor-side converter at the occurrence of grid faults, do not fulfill this requirement, as during the connection of the crowbar, the DFIG behaves as a squirrel cage machine, absorbing reactive power from the grid. This drawback led to the design of control systems that eliminate or even avoid the use of the crowbar. In order to conform to the above-mentioned requirement, this paper proposes a coordinated control strategy of the DFIG converters during a grid fault, managing to ride-through the fault without the use of any auxiliary hardware. The coordination of the two controllers is achieved via a fuzzy controller which is properly tuned using genetic algorithms. using the proposed control system, the DFIG can successfully ride-through the fault, even in the case where the WT feeds a relatively weak ac grid. The over-currents at the rotor windings and the dc side over-voltages are effectively eliminated and the DFIG can continuously supply the electrical system with reactive power during and after the fault, contributing to the support of the ac voltage.
PROPOSED METHODOLOGY
Tuning of Fuzzy Controller is big issue. The Controller is either tuned with the aid of neural network (ANFIS) or Genetic Algorithm. A neural network based controller can be used in place of a Fuzzy Controller for protection of DFIG under fault condition. A back propagation method is used to develop an algorithm to make Stator Active and Stator Voltage controller on the rotor side converter and a DC link Voltage controller in the Grid side converter. Artificial neural network (ANN) consists of highly interconnected simple processing units designed in a way to model how human brain performs a particular task. It is essentially a mathematical model of a non-linear statistical data modeling tool and is a powerful and simple algorithm to approximate nonlinear functions or to solve problems where the input-output relationship is neither well defined nor easily computable. Generally, the procedure of ANN includes 3 steps: model selection, training and learning algorithm, and evaluation. The historical data can be collected by running the model tuned with Conventional PI controller and Resonant Controller used for controlling DFIG under unbalance network conditions. The data collected by running the simulation can be used to train a two-layer feed-forward ANN in which the first layer has one input i.e the error between the reference Value and the actual value. TANSIG and PURELIN are transfer functions of ANN in common use.
CONCLUSION
This paper proposes a control strategy to improve the LVRT capability of grid connected DFIG WTs without the need of any auxiliary hardware. Various methods used in various papers has been studied from past to present. With the increase in the field of Artificial intelligence techniques. ,it is seen that the AI based controllers provides a better control of DFIG under unbalance system network providing reactive power to grid under fault conditions also. The over-currents at the rotor windings and the dc side over voltages are effectively eliminated and the DFIG can continuously supply the electrical system with reactive power during and after the fault, contributing to the support of the ac voltage. The controller based on intelligent techniques can successfully ride the DFIG through the fault, decrease oscillations in Stator active power and electromagnetic torque and keeps DC link Voltage constant even in the case where the WT feeds a relatively weak ac grid.
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27. Dawei Xiang, Li Ran, Member, IEEE, Peter J. Tavner, and Shunchang Yang “Control of a Doubly Fed Induction Generator in a Wind Turbine During Grid Fault Ride-Through” IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 21, NO. 3, SEPTEMBER 2006 pp 652-662.
28. Francisco K. A. Lima, Alvaro Luna, , Pedro Rodriguez, , Edson H. Watanabe, , and Frede Blaabjerg, “Rotor Voltage Dynamics in the Doubly Fed Induction Generator During GridFaults” IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 25, NO. 1, JANUARY 2010 pp-118-130.
29. Lie Xu, Senior Member, IEEE “Coordinated Control of DFIG’s Rotor and Grid Side Converters During Network Unbalance IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 23, NO. 3, MAY 2008 pp-1041-1049.
30. Dawei Xiang, Li Ran, Peter J. Tavner, and Shunchang Yang “Control of a Doubly Fed Induction Generator in a Wind Turbine During Grid Fault Ride-Through” IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 21, NO. 3, SEPTEMBER 2006,pp-652-662.
Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30HealthcareDEMOGRAPHIC AND SOCIO-ECONOMIC CORRELATES OF ACUTE UNDER-NUTRITION IN THE PRE-SCHOOL CHILDREN OF ALLAHABAD, NORTH INDIA
English0912Urvashi SharmaEnglish Neelam YadavEnglish RachanaEnglish Shweta MishraEnglish Pankaj TiwariEnglishObjective: To study the socio-demographic risk factors for the malnutrition in the pre-school children (4-6 years) of Allahabad.
Method: 425 children were surveyed in the study belonging to both the rural and urban parts of the district.
Results: Of the total children studied, there was an almost equal proportion of (50%) of boys and girls. Most of the children
belonged to rural habitat (66.3%). Cases of low weight-for-age (underweight -2SD) were found to be 63.5% of the total studied
population, whereas 39.8% children were low weight- for-height (wasted -2SD).
Conclusion: Parent’s education, per capita income, family size and type of settlement were the key variables identified as risk
factors for under nutrition in pre-school children.
EnglishUnder nutrition, Socio demographic, Risk factorsINTRODUCTION
The initial years of life are a phase of critical physical, mental and psychological growth and development of a child. As pre-schoolers are one of the most easily susceptible and vulnerable group of any community, their health status works as a valuable indicator of the community’s nutritional status [1]. Any sort of nutrient deficit in this period may prove growth limiting which may eventually increase the burden of childhood morbidity and mortality. About 50 per cent of all child deaths is associated with malnourishment and is ascribed to the diarrhea, respiratory infections, measles, and other clinical conditions[2].The results of six studies done by World Health Organization (WHO), a strong association was established between severity of weight-for-age deficits and mortality rates as 54 per cent deaths of under five children in developing countries were accompanied by low weight for age [3].Even micronutrient deficiencies precipitates out in a malnourished children like that of vitamin A[4], Zinc[5] and other co-morbidities [6] .Thus, there emerges an acute necessity of evaluating and eventually exterminating the root causes and risk factors which are playing a significant role in the occurrence of malnutrition.
METHODS
The study was carried out in both the rural blocks and urban wards of the Allahabad district from March to July 2012. All the children recruited for this descriptive study were between 48 to 72 months of age. Data collection was done by a structured interview guided by a pretested questionnaire. Children registered at anganwadi centers of the villages (blocks) and various governmental schools of the urban wards were recruited as the respondents along with the presence of either of the parents. Anthropometric measurements, dietary pattern, nutrient intake and assessment of socioeconomic status were done. Anthropometry was done by trained anthropometrists using standard methods [7]. Z-scores (weight-for-age, heightfor-age, and weight-for-height) were calculated using WHO recommended growth curves [8]. Height and weight were recorded to the nearest 0.5 kg and 0.5 cm respectively by standard methods [7]. Nutritional status classification was done as per the cut off’s given by WHO [9]. Statistical Analysis: Univariate analysis by Chi-square test was used to measure the association of the characteristics with the outcome and logistic regression was used to explore the possibility of the interactions. Software Statistical Package for Social Sciences version 12.0 was used for statistical analysis. Ethical Issues: A written and informed consent was taken from the respondent’s parents. All the participants had an option to opt out of the study at any time during the data collection. The study was approved and registered by the Doctoral Program Committee of the University of Allahabad. The study protocol was approved by the ‘Institutional Ethical Committee Review Board’ (IERB) of Population Resource and Research Centre (PPRC), Kamla Nehru Hospital, Allahabad.
RESULTS
Out of the total children studied 44.7%were above 5 years (Englishhttp://ijcrr.com/abstract.php?article_id=659http://ijcrr.com/article_html.php?did=6591. Sachdev HPS. Assessing child malnutrition - some basic issues. Bull Nutr Foundations India 1995; 16 : 1-5.
2. UNICEF. The state of the world’s children. New York, Oxford University Press, 1998.
3. (No authors listed). Physical status: the use and interpretation of anthropometry. Report of a WHO Expert Committee. World Health Organ Tech Rep Ser.1995; 854:1-452.
4. Sachdeva S, Alam S, Beig FK, Khan Z, Khalique N. Determinants of vitamin A deficiency amongst children in Aligarh district, Uttar Pradesh. Indian Pediatr. 2011;48:861-66.
5. Kapil U, Toteja GS, Rao S, Pandey RM. Zinc Deficiency amongst Adolescents in Delhi. Indian Pediatr.2011; 48:981- 981.
6. Kumar R, Singh J, Joshi K, Singh HP, Bijesh S. Co-morbidities In Hospitalized Children with Severe Acute Malnutrition. Indian Pediatr. 2014; 51:125-127.
7. Gibson RS. Principles of Nutritional Assessment, 2nd ed. 2005. Oxford University Press. London.
8. Group WW. Use and interpretation of anthropometric indicators of nutritional status. Bull WHO. 1986;64:929–41.
9. WHO, WHO Multicenter Growth Reference Study, Measurement and Standardization protocol. , 1998. WHO, limited circulation –WHO/Geneva.
10. Victoria CG. The association between wasting and stunting: an international perspective. J Nutr. 1992; 122:1105- 1110.
11. Joshi HS, Joshi MC, Singh A, Joshi P, Khan NI. Determinants of protein energy malnutrition (pem) in 0-6 years children in rural community of Bareilly. Indian J. Prev. Soc. Med. 2011; Vol. 42 No.2.
12. Cousens S, Nacro B, Curtis V, Kanki B, Tall F, Traore E, Diallo I, Mertens T. Prolonged breast-feeding: no association with increased risk of clinical malnutrition in young children in Burkina Faso. Bulletin World Health Organization.1993; 71(6):713–72.
13. Singh AK, jain S, Bhatnagar M, Singh JV, Garg SL, Chopra H. Socio-demographic determinants of malnutrition among children of 1-6 years of age in rural Meerut . Indian J. Prev. Soc. Med. 2012; Vol. 43:3.
14. Jeyaseelan L , Lakshman M. Risk factors for Malnutrition in south Indian children. Journal of Biosocial Science. 2001; 29: 93-100
15. Basit A, Nair S, Chakraborthy KB, Darshan BB, Kamath A. Risk factors for Under-nutrition among children aged one to five years in Udupi taluk of Karnataka, India: A case control study. Australasian Medical Journal.2012; Vol. 5(3): 163-167.
16. Victora, C. Risk factors for malnutrition in Brazilian children: the role of social and environmental variables. Bulletin World Health Organization. 1986; 64: 299-309.
Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30General SciencesEFFECT OF DIFFERENT PARAMETERS ON BIODECOLOURIZATION OF AZO REACTIVE RED RB DYE FROM TEXTILE EFFLUENT
English1319T. MadhuriEnglish B. Lakshmi KalyaniEnglish P. Suvarnalatha DeviEnglishThe aim of the present study is to isolate textile dye effluent degrading organisms. The synthetic textile dye effluents released into the environment, pollute soil and water ecosystem. Many of these effluents are toxic, carcinogenic and mutagenic in nature which effect aquatic and soil flora and fauna. Thus there is a need of processing these effluents before releasing into the environment. The Bacteria was isolated from soil contaminated with textile dye effluent by serial dilution followed by pour plating technique on nutrient agar medium. The ability of degradation was assessed by decolourization assay. Four isolates (RR1, RR2, RR3 and RR4) had the ability to degrade the dye effluent at different concentrations. The effect of pH, temperature, carbon and nitrogen sources and time course of decolourization was observed. The isolated RR2 and RR3 showed significant decolourization of dye at 600ppm.The ideal temperature was 370C and pH 7 and 9. Both isolates RR2 and RR3 showed optimum growth in media supplemented with sucrose and glucose as carbon source and RR2 showed good growth in ammonium sulphate and RR3 in peptone as a nitrogen source. The result concludes that the RR2 and RR3 isolates showed marked decolourization for textile dye effluent.
EnglishAzo dye, Decolourization, Bioremediation, Red RBINTRODUCTION
Among the textile industries, one of the most extensively used as dyes are synthetic chemicals. Approximately 10,000 different dyes and pigments are used industrially and 0.7 million tonnes of synthetic dyes produced annually, worldwide (Dawker et al., 2008; Rafi et al., 1990). India’s dye industry produces different type of dyes and pigments. Nearly 7,00,000 tonnes of dyes are produced annually Worldwide (Zollinger, 1987). Production of dye stuffs and pigments in India is close to 80,000 tonnes. India is the second large exporter of dye stuffs and intermediates after China (Mathur et al.,2005). Azo dyes being the large group of synthetic dyes constitute up to 70% of all known commercial dyes produced (Carliell et al., 1998). Synthetic dyes generally classified in to reactive, acidic, vat, dispersing, direct and sulphur etc. During the dyeing process, approximately 10-15% of the dyes are released in to the wastewaters, causing serious environmental and health hazards (Chen et al., 2003).Disposal of these dyes into the environment causes serious threat, since they may significantly affect the photosynthetic activity of hydrophtes by reducing light penetration and also toxic to aquatic organisms due to their breakdown products (Hao et al., 2000; Aksu et al., 2007). Dyes may also be toxic to some aquatic life due to the presence of aromatics and metals, chlorides etc (Gupta et al., 2003). The textile finishing generates a large amount of waste water containing dyes and represents one of the largest causes of water pollution (Maulin et al., 2013). Considerable attention has been given in evaluating the capability of microorganisms in decolourizing and degrading the azo dyes. Many studies on the decolourizing capability of microorganisms especially fungi and bacteria have been reported (Feng et al., 2012). Various physical and chemical methods have been used for the removal of dyes from wastewater effluent (Jadhav et al., 2008). However, implementation of physical and chemical methods have inherent drawbacks of being economically unfeasible, unable to completely remove the recalcitrant azo dyes and organic metabolites may cause pollution problems and involving complicated procedures (Forgaus et al., 2004; Jadhav et al., 2008).
MATERIALS AND METHODS
Dyes and characterization Dye
– Reactive red RB was chosen for decolourization in the present study and was provided by a dyeing unit, Satravada, Chittoor District of Andhra Pradesh, India.
Standard dye solution
The dyes were dissolved in sterile distilled water to a concentration of 500 mg/10 ml.
Screening and Identification of microorganisms
Dye degrading bacteria was isolated from the textile industry effluent by serial dilution method (Madigan et al., 2000). The pure isolates were maintained on nutrient agar at 40 C for further use. These isolates were streaked on Luria bertani medium amended with dye, incubated at room temperature and observed for clear zone around the colony. Among the seven isolates four showed the decolourization activity and they were selected for further use.
Decolourization studies
Decolourization activity was expressed in terms of percentage of decolourization and was determined by monitoring the decrease in absorbance at absorption maxima (λmax 518) of respective dye. This was calculated using the following formula as described by (Sani et al., 1999).
Effect of Physicochemical conditions on decolourization activity
Effect of pH and temperature
Various physical parameters like pH (5, 6, 7, 8 and 9) and temperatures (27°C, 37°C and 47°C) were monitored to study their effect on decolourization of reactive red RB dye.
Effect of dye concentration
Different concentrations of dye like 200, 400, 600, 800 and 1000ppm were incorporated into 250 ml Luria bertani medium, inoculated and incubated at optimum conditions.
Effect of differentC and N sources
Different carbon sources like glucose, sucrose, lactose and maltose were incorporated separately into Luria bertani medium at 1% concentration level. Similarly, different sources of nitrogen like yeast extract, peptone and ammonium sulphate at 0.1% concentration were added individually.
Time course of dye decolourization
The time course of decolourization was carried out under optimum conditions are: for RR2 isolate initial dye concentration at 600ppm,pH 7, 37°C, 1% sucrose , and 0.1%ammonium sulphate, for RR3 isolate at initial dye concentration at 600ppm, pH 9, 37°C, 1% glucose and 0.1% peptone. Flasks were incubated up to 36 hours at their respective temperature and samples were removed at regular intervals for every 6 hours and analyzed for decolourization activity as describe above.
STATISTICAL ANALYSIS
The experiment was done in triplicate for each parameter. The results were expressed as percentage of decolourization with respect to control values and compared by two-way ANOVA and DMRT test. A difference was considered statistically significant if p≤0.05.
RESULTS
Screening of dye degrading bacteria
The total seven isolates were isolated from textile dye effluent and screened for degradation by streaking on dye amended Luria bertani medium. Among the seven isolates four showed efficient decolourization. Then the four isolates named as RR1, RR2, RR3 and RR4 respectively. Among the four degraded bacterial isolates, RR3 showed highest decolourization activity followed by RR2, RR1 and RR4 respectively.
Decolourization studies
250 ml of Luria bertani broth amended with 600ppm concentration of red RB dye was inoculated with 4 isolates individually. All the flasks were incubated in static conditions at 370 C for 7 days. 5ml of samples was withdrawn at regular intervals and centrifuged at 10000 rpm for 10min. The supernatant was collected and the percentage of decolourization was measured at 518nm using UV-Spectrophotometer. The uninoculated dye medium supplemented with respective dye was used as blank (Jacob Thomson, 1998). Decolourization activity (%) was calculated by using the above formula and all assays were done in triplicates and the Mean value was taken for statistical analysis.
Effect of Physicochemical conditions on decolourization activity
Effect of pH and temperature
The pH exhibited varied range of effect on dye decolourization (Table 1). RR1, RR2 and RR4 isolates exhibited highest degrading capability at pH 7, whereas RR3 at pH9, respectively. The different temperatures also showed varied range of effect on dye decolourization as shown in (Table 2). All 4 isolates exhibited highest degrading capability at 37°C respectively.
Effect of dye concentration
The different dye concentration exhibited varied range of effect on dye decolourization (Table 3). RR1, RR2, RR3 and RR4 isolates exhibited highest degrading capability at 600ppm concentration.
Effect of different C and N sources
The effect of different carbon sources exhibited varied rang of effects on dye decolourization (Table 4). RR1 and RR2 isolates showed highest degrading capability in sucrose while RR3 and RR4 showed maximum growth in glucose. The different nitrogen sources also showed effect on dye degrading of dye decolourization (Table 5). RR1and RR4 isolates exhibited highest degrading capability in yeast extract, for RR2 in ammonium sulphate and for RR3 in peptone.
Time course of dye decolourization
The present study reveals the high decolourization of textile dye effluent by four isolates with optimization of conditions at 84%, 90%, 94% and 80% of decolourization of dye at 36 hours.
DISCUSSION
Screening of dye degrading bacteria
The process of degradation of textile dyes by employing microorganisms particularly bacteria were also carried out to reduce environmental pollution (Srividhya et al., 2012). The present study was carried out to examine the degradation of dye by isolating the bacteria from textile dye effluents. Among the seven isolates, only four isolates showed positive results for dye decolourization, as indicated by the change and disappearance of colour of the dye from the dye-containing media of the petri plates. A zone of different decolourization around the bacterial colony which might be due to the production of extracellular enzymes by the bacteria during the biodegradation of tested dye (Joshni et al., 2011; Ajay kumar pandey et al., 2012). RR3 and RR2 isolates exhibited maximum decolourization when compared to RR1 and RR4.
Effect of Physicochemical conditions on decolourization activity
Effect of pH and temperature
The pH has a maximum effect on the efficiency of dye decolourization and the optimal pH for colour removable is between 6.0 and 10.0 for most of the dyes (Chen et al., 1999). From the above data it can be inferred that RR3 (91%) at pH 9.0 is the ideal for its activity and is more efficient in decolourizing azo dye, similarly pH plays a great influence in decolourization of Reactive Red 2 dye. These findings are closely similar with alkaline pH for Bacillus species at pH 9.0 showed decolourization percentage was 64.34% by (EI-Sersy et al., 2007). The results revealed that RR3 is more efficient in decolourizing azo dye at 37°C is the ideal temperature for its activity. Our results similar to that (Ponaj et al., 2011) were reported as the range of activity on decolourization of orange 3R with Bacillus sps at 37°C was 78.57%. Centin et al. (2006) reported that decolourizing activity was suppressed at 45°C, might be due the loss of cell viability or deactivation of the enzymes responsible for decolourization at higher temperature.
Effect of dye concentration
Maximum dye degradation was observed at 600ppm concentration for four isolates. However, when the dye concentration was high, the isolates showed less capability. Similar results were also mentioned by (Khalid et al., 2012).Dye concentration can influence the efficiency of microbial decolourization through a combination of factors including the toxicity imposed by dye at higher concentration (Sahasrabudhe et al., 2011).
Effect of different C and N sources
RR3 and RR4 exhibited maximum growth in glucose. Dyes being deficient in Carbon sources the biodegradation of dyes without any extra Carbon sources is very difficult (Senan et al., 2004). The reason for low decolourization at sucrose, fructose and maltose might be that this carbon sources could not meet the good growth requirements for the bacterial isolate. Wang et al., (2009) reported a Citrobacter sps, decolourized by 96.2% of reactive red 180 dye with 4g/l of glucose as carbon source. Bacterial utilization of azo dyes as a source of carbon and energy has been reported by (Yatome et al., 1993; Dykes et al., 1994).RR2 showed maximum in ammonium sulphate and RR3 in peptone as a nitrogen source. From the above data it was revealed that RR3 is more efficient in decolourizing azo dye with peptone is the ideal nitrogen source for its activity .The similar results was observed by (Chen et al.,1999;Liu et al., 2006). The presence of peptone regenerates NADH and this acts as an electron donor for the azo dye reduction. In addition, peptone significantly enhances the strain’s activity of azo dye decomposition and colour removal rate was increased with rise in peptone concentration (40 g l-1). The nitrogen sources were less efficient than carbon source availed by microorganism (Ola et al., 2010).
Time course of dye decolourization
The time course of decolourization of reactive red RB dye under optimum conditions was 36 hours for RR2 90%, whereas 94% of decolourization was observed in RR3 isolate within 36 hours showed (Table 6 and 7).The outcomes of this experiment indicated that RR2 and RR3 showed the decolourization process to a better extent than RR1 and RR4. However, both the species of bacteria can be inferred as good agents for the degradation of azo dye. Jothimani et al., (1998) has reported 59% dye removal from a dyeing industry effluent using pseudomonas sps.
CONCLUSION
The present study concludes that dye degrading microorganisms RR2 and RR3from an effluent contaminated site of textile dyeing industry have potential of decolourization. This observation has established that the bacteria’s are adaptive in nature and can degrade the dye contaminants. Thus, it is concluded that the bacterial isolates can be used as a good microbial source for textile waste water treatment.
ACKNOWLEDGEMENT
Authors acknowledge the immense help received from the scholars whose articles are cited and included in reference of this manuscript. The authors are also grateful to authors/ editors/ publishers of all those articles, journals and books from where the literature for this article has been reviewed and discussed. Authors are highly grateful to the Department of Applied Microbiology, DST-FIST, CURIE, Sri Padmavathi Mahila Visavavidyalam, Tirupati, Andhra Pradesh, India for providing Research facilities.
Values are the means of triplicates ± SD.
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Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30HealthcarePERINATAL MORTALITY IN HYPERTENSIVE DISORDERS WITH PREGNANCY
English2023Parmar P. H.English Gosai K. I.English Dhudhrejia K. M.English Goswami K. D.English Prajapati S. S.English Panchiwala J. V.EnglishBackground: Preeclampsia is one of the common conditions of unknown etiology which increases the risk of maternal and
perinatal morbidity and mortality.
Objective:
1. To find out Perinatal Mortality Rate in cases of hypertensive disorders with pregnancy.
2. To compare Perinatal Mortality Rate in Booked and Unbooked cases in cases of hypertensive disorders with pregnancy.
3. To compare Perinatal Mortality Rate in patients receiving Early and Late treatment in cases of hypertensive disorders with
pregnancy.
Materials and Methods: A comparative prospective Study was performed at Dept of OBS & Gynec, P D U Medical College, Rajkot over a period of June 2011 to May 2012. All the patients admitted with the diagnosis of hypertensive disorders with pregnancy were included in the study. A detailed history, with clinical symptoms and sign, laboratory investigations, diagnosis, and neonatal outcome were recorded in the predefined questionnaire proforma. Up to seven-day neonatal follow up was done.
Results: Perinatal mortality rate in cases of hypertensive disorders with pregnancy of our study was 327/1000 live births (36 out of 110 cases). In our study, we found 54 booked cases and 56 unbooked cases; out of which perinatal mortality was in 9(16%) cases in booked case while 27 (48%) cases in unbooked cases. So, Perinatal Mortality Rate in booked cases was 166 / 1000 live birth while in unbooked cases it was 482 / 1000 live birth. Perinatal mortality rate was three times higher in unbooked cases (P = 0.0004). Perinatal mortality rate in patients early diagnosed and treated was 127/1000 live births, while in delay diagnosed and treated was 476/1000 live births. So, perinatal mortality rate was three & half times higher in cases delay diagnosed & treated cases
(P = 0.0001).
Conclusion: We studied impact of hypertensive disorders with pregnancy on Perinatal outcome and found Perinatal mortality
rate of 327/1000 live births. PMR was significantly high in unbooked and cases with delayed treatment. So, we concluded that
early diagnosis and treatment of hypertensive disorders with pregnancy can improve perinatal outcome.
EnglishPerinatal Mortality Rate, hypertensive disorders with pregnancyINTRODUCTION
Hypertensive disorders of pregnancy have been identified as a major worldwide health problem, associated with increased perinatal morbidity and mortality. Pregnancy induced hypertension (PIH) is one of the most common causes of both maternal and neonatal morbidity. [1] It is estimated that globally 6-8% of pregnancies are complicated by hypertension regarding population and the diagnostic criteria [2, 3, 4]. Five classes of hypertensive disorders were identified according to the latest classification system described by the National High Blood Pressure Education Working Group (2000) including Preeclampsia, Eclampsia, Transient Hypertension of pregnancy, Chronic Hypertension and Preeclampsia superimposed on Chronic Hypertension [5]. Risk factors for preeclampsia include medical conditions with the potential to cause microvascular disease (e.g., diabetes mellitus, chronic hypertension, vascular and connective tissue disorders), antiphospholipid antibody syndrome, nephropathy, twin pregnancies, primiparity, previous PE and obesity. A family history of PE increases the women’s risk, suggesting a possible genetic predisposition [6, 7, 8]. Hypertensive disorders of pregnancy predispose women to acute or chronic uteroplacental insufficiency, resulting in ante or intrapartum asphyxia that may lead to fetal death, intrauterine growth retardation and/or preterm delivery [9]. The perinatal mortality and stillbirth rates for India according to National Family Health Survey-3 (2005-06) are 48.5 per 1000 live births and 19.2 per 1000 pregnancies, respectively [10]
MATERIAL AND METHODS
A comparative prospective Study was performed at Dept of obs & gynec, P D U Medical College, Rajkot over a period of June 2011 to May 2012. All the patients admitted with the diagnosis of hypertensive disorders with pregnancy were included in the study. We divided patients in to booked and unbooked categories. Those who have two or more antenatal visits at OBGY Dept, P.D.U Medical College, Rajkot were considered booked patients and others into unbooked categories. We also divided patients into early and delayed treatment categories. If any time of admission patient has been diagnosed as hypertensive disorder of pregnancy and treatment has been started considered early treatment categories else included in delayed category. Convulsion controlled by inj. MgSo4 both IM &/IV doses and hypertension controlled by antihypertensive drugs like Cap. Nifidipine /Methyldopa /Lobetelol .Vaginal delivery aimed but when indicated delivery by caesarian section. A detailed history, with clinical symptoms and sign, laboratory investigations, diagnosis, and neonatal outcome were recorded in the predefined questionnaire proforma. Up to seven-day neonatal follow up was done.
RESULTS
We have done a prospective observation study of Perinatal mortality in case of hypertensive disorders with pregnancy. Total 110 patients included during the study period. Patients of different age group, parity, area of residence, socioeconomical class, literacy level, religion and gestational age were included. We found out of total 110 cases in 36 cases Perinatal mortality were noted. So, Perinatal Mortality Rate was 327/1000 live birth. In our study, out of 54 booked cases perinatal mortality in 9 cases (means 16%) and Perinatal Mortality Rate in booked cases was 166 / 1000 live birth, while out of 56 unbooked cases perinatal mortality in 27 cases. (means 48%) and Perinatal Mortality Rate in unbooked cases was 482 / 1000 live birth. Chi square test suggests that perinatal mortality significantly increases in unbooked than booked cases [P = 0.0004 (4.23 E - 4)]. In our study, 47 cases received early treatment & perinatal mortality was in 6 cases (means 13%) and Perinatal Mortality Rate early diagnosed & treated cases was 127 / 1000 live birth, while 63 cases received delay treatment and perinatal mortality in 30 cases (means 48%). Perinatal Mortality Rate in delay diagnosed & treated cases was 476 / 1000 live birth. Chi square test suggests that perinatal mortality significantly increases in delay treated cases than early treated cases [P = 0.0001 (1.16 E - 4)]. Out of 110 cases 11(10%) belongs to still birth while 99(90%) belongs to live birth at time of delivery. In our study, low birth weight was the most common cause of early neonatal death (most commonly due to iugr followed by preterm) while second most common cause was severe birth asphyxia & third was meconium aspiration syndrome.
DISCUSSION
Out of total 110 cases in 36 cases perinatal mortality were noted. So, Perinatal Mortality Rate was 327/1000 live birth. Perinatal Mortality Rate in unbooked cases was 482 / 1000 live birth While Perinatal Mortality Rate in booked cases was 166 / 1000 live birth. Perinatal Mortality Rate in delay diagnosed & treated cases was 476 / 1000 live birth while Perinatal Mortality Rate in early diagnosed & treated cases was 127 / 1000 live birth. Many studies have been published about effects of hypertensive disorders with pregnancy on perinatal outcome. Zenebe Wolde et al, evaluated hypertensive disorders of pregnancy in Jimma University specialized hospital and noted perinatal mortality rate in the study was 317.1 / 1000 births [11] almost same to our study while in study of J. Nadkarni et al perinatal mortality rate was 159/1000 births [12]. 20% of births needed to be delivered by Cesarean section in our study lesser compared to similar study by Chappell et al [13]. In our study Perinatal Mortality Rate in unbooked cases was 482 / 1000 live birth While Perinatal Mortality Rate in booked cases was 166 / 1000 live birth While J. Nadkarni et al reviewed perinatal mortality rate in booked cases was 86.9/1000 births compared to 185.6/1000 births in mothers with emergency admission [12].
CONCLUSION
We studied impact of hypertensive disorders with pregnancy on Perinatal outcome and found Perinatal mortality rate of 327/1000 live births. Out of 110 cases 11(10%) belongs to still birth while 99(90%) belongs to live birth at time of delivery.PMR was significantly high in unbooked and cases with delayed treatment. So, we concluded that early diagnosis and treatment of hypertensive disorders with pregnancy can improve perinatal outcome.
Englishhttp://ijcrr.com/abstract.php?article_id=661http://ijcrr.com/article_html.php?did=6611. Cunningham FG et al.. Hypertensive disorders in pregnancy.In MacDonald, PC et al., eds. Williams Obstetrics, 21st ed. 2003; McGraw Hill; 557-618).
2. Tomi? V, Petrovi? O, Petrov B, Bjelanovi? V, Naletili? M. Hypertensive disorders in pregnancy: a 5-year analysis of the wartime and postwar period in South-Western region of Bosnia and Herzegovina. Coll Antropol. 2009;33:115-9. [PubMed]
3. Roberts CL, Algert CS, Morris JM, Ford JB, HendersonSmart DJ. Hypertensive disorders in pregnancy: a population-based study. Med J Aust. 2005;182:332-35. [PubMed]
4. Tavassoli F, Ghasemi M, Ghomian N, Ghorbani A, Tavassoli S. Maternal and perinatal outcome in nulliparious women complicated with pregnancy hypertension. JPMA. 2010;60:707.
5. National High Blood Pressure Education Program Working Group, author. Report of the National High Blood Pressure Education Program Working Group on high blood pressure in pregnancy. Am J Obstet Gynecol. 2000;183:S1–S22
6. Sibai B, Dekker G, Kupferminc M. Pre-eclampsia. Lancet 2005;365:785-799.
7. ACOG Committee on Practice Bulletins-Obstetrics. Diagnosis and management of preeclampsia and eclampsia. American College of Obstetricians and Gynecologists. Obstet Gynecol 2002;99:159-167.
8. Dekker G, Sibai B. Primary, secondary, and tertiary prevention of pre-eclampsia. Lancet 2001;357:209-215
9. Naeye RL, Friedman EA. Causes of perinatal death associated with gestational hypertension and proteinuria. Am J Obstet Gynecol 1979; 133: 8-10.
10. National Family Health Survey-3: Summary of findings. Available from http://www.nfhsindia.org/NFHS-3%20 Data/VOL-1/Summary%20of%20Findings%20 (6868K). pdf. Accessed on October 13, 2011.
11. Zenebe Wolde, Hailemariam Segni, Mirkuzie Woldie.Hypertensive Disorders of Pregnancy in Jimma University Specialized HospitalEthiop J Health Sci. 2011 November; 21(3): 147–154
12. J. Nadkarni,J. Bahl,P. Parekh. Perinatal Outcome in Pregnancy Associated Hypertension. Indian Pediatrics 2001; 38: 174-178.
13. Chappellet al.. Adverse Perinatal Outcomes and Risk Factors for Preeclampsia in Women With Chronic Hypertension.2008; 51: 1002-1009.
Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30HealthcareEFFECT OF RIGID TAPING ON PAIN AND GAIT PARAMETERS IN KNEE OSTEOARTHRITIS
English2427Anood FaqihEnglish Ulka GavankarEnglish Neha TambekarEnglish Savita RairikarEnglish Ashok ShyamEnglish Parag SanchetiEnglishBackground: The incidence of osteoarthritis has been seen to increase drastically over the years. The symptoms of osteoarthritis include pain, swelling, loss of function, changes in gait and an overall reduction in the quality of life. A lot of studies have been performed for the treatment of symptomatic relief of these patients including cryotherapy, kinesiotaping, therapeutic modalities. However, limited studies have been conducted on the immediate symptomatic relief with rigid taping and the effect on gait parameters. Hence, the purpose of this study is to know the effect of rigid taping on pain and gait parameters in knee osteoarthritis.
Methods: 120 subjects having bilateral osteoarthritis of the knee were screened according to the inclusion and exclusion criteria and were included in the study. Pain was assessed using the Visual Analog Scale and gait parameters such as stride length, step length and cadence were assessed using the footprint method pre and post application of a rigid tape.
Results: To measure the changes in pain intensity and gait parameters such as step length, stride length and cadence pre and post taping paired T test was used. The level of significance was set at p value ? 0.05.
Changes in pain intensity, step length, stride length and cadence, p=0.00 which shows that there is significant change in the above characteristics after the application of a rigid tape.
Conclusion: From this study, it was hence concluded that after rigid taping there was a significant decrease in the pain intensity and the gait parameters such as step length, stride length and cadence improved in patients with knee osteoarthritis.
EnglishStep length, Stride length, Cadence, TapeINTRODUCTION
Osteoarthritis (OA) is a degenerative condition of the joint which involves mainly the articular cartilage and the subchondral bone. This is a condition in which natural cushioning between joints and cartilage wears away causing friction between articulating surfaces. This leads to pain, swelling around joint, stiffness, crepitus, abnormal gait pattern, deformities, and spur formation.[1]OA is a common condition seen after 40 years of age and is widespread in adults older than 65.[2]The incidence of osteoarthritis has been increasing drastically over the years. Knee is an important weight bearing joint in the body. Walking is the most common method of human locomotion and causes repetitive joint loading. Hence, gait is commonly affected in patients having osteoarthritis.[3] Due to pain the patient tends to walk with an antalgic gait and this inturn affects the gait parameters. The presence of pain and radiographic joint degeneration defines OA clinically.[4] OA is commonly graded on radiographs using the Kellgren and Lawrence scale[2]. Taping has been used as a part of rehabilitative and prophylactic programmes in managing musculoskeletal disorders.[5] Taping has been used as a method in physical therapy to reduce pain.[6][7][8] There are different types of taping techniques available. A rigid tape is an inelastic adhesive tape. Prior to the application of a rigid tape, a protective under wrap is commonly used.[5] Taping helps provide support to the injured soft tissues including ligaments, tendons and muscles. It helps limit unwanted joint movement. It allows optimal healing without causing unwanted stress on the tissues which are injured. It helps to support and protect the structures in a functional position during strengthening, exercise etc. Taping also enhances proprioceptive feedback from the part to which it is applied.[9] The purpose of this study was to know the effect of rigid taping on pain and gait parameters such as step length, stride length and cadence in patients having osteoarthritis of the knee.
METHODS AND METHODOLOGY
Informed consent was taken from the subjects. The study was performed on 120 subjects in outpatient physiotherapy departments. The study design was a quasi experimental type of study and the method of sampling was purposive. Inclusion Criteria was patients in the age group of 40-70 years with bilateral patello-femoral and medial compartmental osteoarthritis of the knee. Those having lateral patella tracking and grade 1-2 on Kellgren and Lawrence grading for osteoarthritis on radiographs Exclusion Criteria was patients giving a history of hypersensitive skin or any other skin conditions. Patients having sensory and motor deficits. Any fracture of the lower limb, any other inflammatory condition of other joints and any other concurrent pain.
Procedure
Study and study design were approved by the institutional review board. Patients were screened according to the inclusion criteria and were included in the study. They were evaluated using the Visual Analog Scale for pain and gait analysis was done in a 2D gait lab using the foot print method pre taping. Rigid tape was applied for the knee. An underwrap was applied before the application of the rigid tape. An underwrap is a thin polyurethane foam material used for the protection of sensitive skin. Patient was in a sitting position with knee in full extension. One anchor strap was placed over the superior pole of patella. One strip of tape was attached to the anchor on the medial side of the knee and was pulled obliquely downwards to the lateral side with the top edge of the tape passing just under the inferior pole of the patella. The same action was repeated lateral to medial to make a cross-over effect. Gait parameters such as step length, stride length and cadence were measured. Re-evaluation for pain and gait parameters was done immediately after application of rigid taping. Step length was measured as the linear distance between the two successive points of contact of opposite extremities i.e. from heel strike of one extremity to the heel strike of the opposite extremity. Stride length was measured as the linear distance from the point of one heel strike of one lower extremity to the point of the next heel strike of the same extremity. Cadence was measured by the number of steps the patient took in a duration of 10 seconds.[10]
RESULTS
To measure the changes in pain intensity and gait parameters such as step length, stride length and cadence pre and post taping paired T test was used. The level of significance was set at p value ≤ 0.05. Changes in pain intensity, step length, stride length and cadence p=0.00 which shows that there is significant change in the above characteristics.
DISCUSSION
This study has shown that after the application of a rigid tape to the knee joint, there was a significant reduction in the pain intensity and gait parameters such as step length, stride length and cadence improved significantly. The taping technique used in this study, helped to unload the quadriceps tendon thereby reducing the stresses over the quadriceps tendon attachment. [11] This could explain the reduction in pain intensity of the subjects. Table 1 shows that post rigid taping there was a significant reduction in the pain intensity in both the knees. When a medially directed force is applied to the patella, it increases the patella-femoral contact, thereby, reducing stresses and improving pain. [6] Also, therapeutic taping helped improve pain and disability significantly in patients with knee osteoarthritis. [8] According to this study, there was a significant improvement in the gait parameters such as step length, stride length and cadence (Table 2, 3, 4). Patella taping helped correct the mal-alignment of the patella improving the efficiency of the quadriceps muscle which is an important muscle involved during gait. Correcting the mal-alignment of the patella and in turn the quadriceps attachment improves the biomechanical efficiency or pull of the quadriceps muscle. Also, unloading the tendon helped reduce stresses over the quadriceps attachment reducing pain. All these factors helped to improve the overall function of the quadriceps musculature. Position of the patella has a strong influence on the function of the quadriceps muscle. The patella acting like an anatomical pulley lengthens the mechanical advantage of the quadriceps by increasing the distance of the quadriceps tendon from the knee joint axis. The line of action of the quadriceps femoris is deflected away from the center of the joint by the patella which increases the angle of pull and the muscles ability to produce an extension torque. Patella-femoral joint reaction and compressive forces are high during daily activities such as walking. [12] Taping the patella to control spin, tilt, lateral glide to optimize pain is useful for efficacy and causes possible early vastus medialis obliquis (VMO) onset and improves functional capacity of the knee. [13] Taping has shown to influence the patella-femoral joint functioning. [14] A study done on the effectiveness of ankle taping on the kinematics of ankle joint during level ground walking showed that there was a significant change in step length, step duration, double stance and swing phase post ankle taping.[15] Pain limits functional activities and may lead to an overall reduction in the quality of life of the patient. Walking is an important activity of daily living which is affected in patients with osteoarthritis. Muscle pain modulates the function of the quadriceps muscle during the loading phase of walking and may lead to impaired knee joint function. [16] Hence, rigid taping is an easy, cost effective and an efficient way of treatment of pain relief. It can, therefore, be a handy tool in clinical practice for the immediate symptomatic relief of OA by reducing the pain and improving the gait parameters such as stride length, step length and cadence. Study Limitations: Effect of rigid taping could be measured on other parameters of gait.
CONCLUSION
From this study, it was concluded that rigid taping showed a significant improvement in pain of patients with osteoarthritis and hence there was improvement seen in all the gait parameters such as step length, stride length and cadence.
ACKNOWLEDGEMENT
Authors acknowledge the immense help received from the scholars whose articles were cited and included in references of this manuscript. The authors are also grateful to authors / editors / publishers of all those articles, journals and books from where the literature for this article has been reviewed and discussed. We would also like to thank all our participants and for their valuable time and participation.
Financial Support: None
Conflict of Interest: None
Englishhttp://ijcrr.com/abstract.php?article_id=662http://ijcrr.com/article_html.php?did=6621. Maheshwari J. Essential Orthopaedics. 3rd Edition(Revised). New Delhi: Mehta Publishers; 2005.p 252-253.
2. O’Sullivan S, Schmitz Thomas. Physical Rehabilitation. 5th Edition. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2006, p1067.
3. Henriksen M, Graven-Nielsen T, Aaboe J, Andriacchi TP, Bliddal H. Gait changes in patients with knee osteoarthritis are replicated by experimental knee pain. Arthritis Care and Research. 2010; 62(4): 501-509.
4. Altman R, Asch E, Bloch D, Bole G, Borenstein D, Brandt K, et al. Development of criteria for the classification and reporting of osteoarthritis: classification of osteoarthritis of the knee. Diagnostic and Therapeutic Criteria Committee of the American Rheumatism Association. Arthritis Rheumatism.1986; 29(8):1039–49.
5. Alexander CM, McMullan M, Harrison PJ. What is the effect of taping along or across a muscle on motoneurone excitability? A study using Triceps Surae. Manual Therapy. 2008; 13(1): 57-62.
6. Handbook of Non Drug Intervention (HANDI) Project Team. Taping for knee osteoarthritis. Australian Family Physician. 2013 Oct;42(10):725-6.
7. Hinman RS, Crossley KM, McConnell J, Bennell KL. Efficacy of knee tape in the management of osteoarthritis of the knee: blinded randomised controlled trial.BMJ. 2000; 327(7407):135.
8. Hinman RS, Bennell KL, Crossley KM, McConnell J. Immediate effects of adhesive tape on pain and disability in individuals with knee osteoarthritis. Rheumatology (Oxford). 2003;42(7) 865-9.
9. Macdonald R. Taping techniques- Principles and practice. 2nd Edition.Butterworth-Heinemann;2004. p3-4.
10. Levangie a, Norkin C. Joint structure and function- A comprehensive analysis. 4thEdition. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2006. p523.
11. Macdonald R. Taping techniques- Principles and practice. 2nd Edition.Butterworth-Heinemann; 2004. p118-119.
12. Levangie P, Norkin C. Joint structure and function- A comprehensive analysis. 4th Edition. New Delhi: Jaypee Brothers Medical Publishers (P) Ltd; 2006. p416,424.
13. Barton C, Balachandar V, Lack S, Morrissey D. Patellar taping for patella-femoral pain: a systematic review and metaanalysis to evaluate clinical outcomes and biomechanical mechanisms. British Journal of Sports Medicine. 2014; 48(6):417-24.
14. Herrington L, Malloy S, Richards J. The effect of patella taping on vastus medialis oblique and vastus laterialis EMG activity and knee kinematic variables during stair descent. Journal of Electromyography and Kinesiology. 2005; 15(6):604-7.
15. Choukou MA, Hijazi S. Effectiveness of ankle taping on ankle joint kinematics during walking on level ground. Foot & Ankle Speclist. 2013;6(5):352-5.
16. Henriksen M, Alkjaer T, Lund H, Simonsen EB, Graven-Nielsen T, Danneskiold-Samsøe B, Bliddal H. Experimental quadriceps muscle pain impairs knee joint control during walking. Journal of Applied Physiology.2007;103(1):132-139.
Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30HealthcareEVALUATION OF LIVER SPACE OCCUPYING LESION WITH SPECIAL REFERENCE TO ETIOLOGY AND CO-MORBID CONDITION
English2833Sahid Imam MallickEnglish Phani bhusan SarkarEnglish Sauvik DasguptaEnglish Auriom KarEnglish Soumavo MukherjeeEnglish Sneha Jatan BothraEnglish N B DebnathEnglishBackground: Identifying etiology and co-morbid conditions of SOL liver is important for further management.
Objectives: To evaluate the different causes of Space Occupying Lesion (SOL) of liver and find out etiology of liver tumor among
patients of SOL of liver and also short term follow up of treatable condition.
Method: Observational study is done over 1 year on 40 patients aged above 12 years with SOL liver who has attended General
Medicine outdoor and/or indoor of NRS Medical College and Hospital. Longitudinal type of prospective study techniques have
been used to analyses data.
Results: The study shows that the highest percentage (27.5) of SOL seen in 51-60 years of age group and male were affected
more than females (70% and 30% respectively). Metastatic adeno carcinoma was the commonest cause of liver SOL (32.55) followed
by amoebic and pyogenic liver abscess (20% and 15% respectively). On 6 months follow up there was 83.33% complete
resolution of pyogenic abscesses and 37.5% complete resolution of amoebic liver abscesses.
Conclusion: Majority of liver SOL are metastatic adenocarcinoma. Next common SOL is amoebic liver abscess, followed by
pyogenic liver abscess. Majority of liver abscesses responded with antibiotics.
EnglishLiver, Space Occupying Lesion (SOL), Adenocarcinoma, Liver abscessINTRODUCTION
Space Occupying Lesion (SOL) on liver can be caused by various diseases that may or may not be manifested with symptoms. Mass lesions of the liver occur quite frequently, thus clinicians interested in liver diseases should have a thorough understanding of their presentations, diagnosis and treatment. Hepatic mass lesions include tumors, tumor-like lesions, abscesses, cysts, hemartomas and confluent granulomas. The frequency with which each is seen varies in different geographic regions and different populations. Focal nodular hyperplasia is more common than hepatocellular adenoma. Focal nodular hyperplasia occurs at all ages, but most patients present in the third and fourth decades of life.(1) The cause of focal nodular hyperplasia is unknown. Some evidence suggests that focal nodular hyperplasia may be hormone-dependent.(2), (3) The liver is the most common destination of hydatid cyst (70%), followed by the lungs (20%), kidney, spleen, brain, and bone. The sensitivity and specificity of both ultrasonography and CT in confirming the diagnosis are high. (4) In adults in most part of the world, hepatic metastasis are more common than primary malignant tumors of the liver, whereas in children, primary tumors outnumber both metastases and benign tumors of the liver. Hepatic metastases occur in 40% to 50% of adult patients with extra hepatic primary malignancies.(5) Most cases of pyogenic liver abscess are cryptogenic or occur in older men with underlying biliary tract disease.(6) Different liver SOL has different etiology and risk factor, so it is important to find out etiology and risk factor in Indian subcontinent, which would help us to treat different kind of SOL of liver.
MATERIALS AND METHODS
This observational study was conducted among the liver SOL patients who attended Medicine OPD and indoor of Nil Ratan Sirkar (NRS) Medical College, Kolkata. The study participants were above 12 years of age. The study was conducted for about 1 year. The sample size of 40 were included who were satisfying inclusion criteria. The inclusion criteria were patients having clinically and radiologically confirmed hepatic SOL above 12 years of age with consent from patient’s relatives. The patients who were seriously ill and age below 12 years were excluded from this study. The data was collected to study demographic profile like age, sex, religion and assessment of co morbid condition and risk factors. All patients were undergone detailed clinical examination and routine as well as specific blood and imaging study. Longitudinal type of prospective study was used as study techniques. Ethical committee approval was obtained from the Institutional Ethical Committee of Nil Ratan Sircar Medical College, Kolkata. After obtaining the required permission from the Medical college and hospital, the study participants were briefed about the nature and purpose of the study.
RESULTS
A total of 40 patients above the age of 12 years with liver SOL were studied regarding their demographic profile, etiology, co-morbidity, and risk factor. The present study was carried out at the department of medicine, N.R.S Medical College and Hospital, Kolkata from February 2012 to March 2013. In this study it has been seen that highest percentage (27.5%) of SOL seen in 51-60 age group. Figure 1 showing distribution of liver SOL according to age group. This study reveals 70% of male having liver SOL and 30% of female having liver SOL. Table number 1 showing distribution of study population according to sex. In this study out of 40 patients Hindu patients were 34(85%) and Muslim patients were 6(15%). Metastatic adenocarcinoma was commonest cause of liver SOL found in our study (32.5%), out of which 10 patients were male and 3 were female. Amoebic liver abscess was second most common cause of liver SOL in our study (20%), followed by Pyogenic liver abscess (15%). Haemangioma was found in 10% of population and 7.5% of patient had Hepatocellular carcinoma. Simple liver cyst was found in 5% of patient. Metastatic neuro-endocrine tumor, Adenoma, Hydatid cyst and Focal Nodular Hyperplasia were the other causes of liver SOL found in our study (each 2.5%). Among the metastatic adenocarcinoma, lung was the commonest primary site (39.76%) found in our study. In 3 patients we could not locate the primary site (i.e. 23.07%). Colon and Cholangiocarcinoma was primary site in 15.38% of patients among the Metastatic adenocarcinoma. Table No. 3 showing distribution of Metastatic adenocarcinoma according to primary source. Table 4 showing Klebsiella pneumonia was the commonest organism causing pyogenic liver abscess (33.33%), whereas in same percentage of patients of liver abscess no growth were found. Among the Pyogenic liver abscess patients 4 patients had less than 5 cm of abscess size (67.67%) and more than 5 cm abscess size was found in 2 patients (33.33%). Out of 6 Pyogenic liver abscess patients 4 were treated with antibiotics only and other 2 were treated jointly with antibiotics and aspiration. Among 6 Pyogenic liver abscess patients 3 patients had co-morbid condition like Diabetes Mellitus and 1 patient had Cholangitis. Out of 8 Amoebic liver abscess patients found in our study, 7 were male (87.5%) and 1 patient was female (12.5%). 75% Amoebic liver abscesses were single in number and 25% were single abscess. In our study, all 8 amoebic abscesses were less than 5 cm in size. All 8 patients of amoebic abscess in our study were responded well to treatment with Metronidazole and Diloxanide fuoate. Two hepatocellular carcinoma patients have Hepatitis C (66.66%) and other patient has Hepatitis B (33.33%). Cirrhosis of liver and alcoholism were present in 2 patients of hepatocellular carcinoma. 3 male and 1 female patients were found to have hemangioma in our study. Both the benign tumor of liver, namely adenoma and focal nodular hyperplasia were found in female only. And in both the case, oral contraceptive pill was common risk factor. Amoebic and pyogenic liver abscess patients were followed up in OPD on regular interval. After 6 months 83.33% of pyogenic liver abscess patients had complete resolution and 16.67% had residual abscess. Whereas, in case of amoebic liver abscess, only 37.5% had complete resolution and 62.5 %( Table No. 6) had residual abscess after 6 months of follow up.
DISCUSSION
A. Demography, Etiology and Risk factors :
• During one year study period total 40 cases selected randomly satisfied inclusion criteria attending medicine outpatient department and inpatient department. Minimum age were 22 yrs and maximum age were 76 yrs. Mean of age were 50.15yrs. standard deviation of age were 14.43.
• In this study maximum number of liver SOL is found 51-60yrs age group (27.5%).
• Male are commonly affected than female. Out of 40 patients 28(70%) patients were male and 12(30%) patients were female.
• Among the total patients 34(85%) patients were
Hindu and 6(15%) patients were Muslim. Among 40 patients 13(32.5%) had metastatic adeno carcinaoma, 8(20%) patients had amoebic liver abscess, 6(15%) patients had pyogenic abscess, 4(10%)patients had haemangioma, 3(7.5%) patients had hepatocellular carcinoma. 2(5%) patients had simple cyst, 1(2.5%) patient had adenoma, 1(2.5%) patient had focal nodular hyperplasia. 1(2.5%) patient had hydatid cyst, 1(2.5%) had metastatic neuro-endocrine carcinoma. A study by Dr. Syed Mehdi Raza Rizvi, Allied Hospital, Faisalabad(7) revealed that primary liver malignancy were 61.6%, metastatic liver malignancy were 16.7%, liver abscess were 8.3%, focal nodular hyperplasia were 5%, simple cyst were 5%, hemangiomas were 3.3% out of 120 patients. In comparison to this study, it has been seen that in our study metastatic adenocarcinoma and liver abscesses occurring more frequently. This difference may be due to difference in number of patients studied. In this study, maximum number of liver SOL is found metastatic adenocarcinoma. Out of 13 metastatic adenocarcinoma patients, 4(30.76%) patients’ primary sources were in Lung. Colon and cholangiocarcinoma was primary sources in 2(15.38%) patients each. After thorough investigation as per protocol, primary sources of metastatic adenocarcinoma of liver were unknown in 3(23.07%) patients. Among 13 patients of metastatic adenocarcinoma of liver, male patients were 10(76.92%) and female patients were 3(23.08%).
• Out of 40 patients 6(15%) patients had pyogenic abscess. Single abscess is found in 2(33.3%) patient and multiple abscesses are found in 4(67.7%) patients. Among 6 patients 4(66.67%) patients are associated with diabetes mellitus and 2(33.3%) patients are associated with cholangitis. No organism identified in 2(33.33%) patients out of 6 patient of pyogenic abscess by culturing blood and pus from abscess. These may be due to antibiotic therapy started before arriving hospital. Out of 6 patients of pyogenic liver abscess organism identified were klebsiella pneumonia in 2(33.33%) patients, E.coli and Staphylococcus aureus was found in 1(16.66%) patient each. The study showed, in pyogenic abscess associated with Diabetes mellitus most commonly identified Organism was Klebsiella pneumonia. Out of 6 patients of pyogenic liver abscess 4(67.7%) patients were male and 2(33.3%) patients were female. Among 40 patients 8(20%) patients had amoebic abscess. Out of 8 patients 7(87.5%) patients were male and 1(12.5%) was female. Single abscess was found in 6(75%) patients and multiple amoebic abscesses are found in 2(25%) patient. In contrast to pyogenic abscess, amoebic abscess occur commonly single in number. All patients improved with anti-amoebic drug therapy. Therapeutic aspiration and surgical drainage were not needed as most of the lesion in right lobe and size of abscess in all patients were less than 5cm.
• Out of 40 patient’s hepatocellular carcinoma were found in 3(7.5%) patients. Hepatitis B positive patients were 1(33.33%) and hepatitis C positive patient were 2(66.67%). Out of 3 patients of hepatocellular carcinoma 2(66.67%) were alcoholic. In contrast to other study it is seen that hepatitis C associated hepatocellular carcinoma occurring more commonly than hepatitis B associated hepatocellular carcinoma.
• Hemangioma was found 4(10%) patients out of 40 patients. Among 4 patient of hemangioma 3(75%) patients were male and 1(25%) was female. Size of hemangioma was less than 4cm in all 4 patients. In contrast to other study it is seen that hemangioma occurring more common in male.
• In this study adenoma and focal nodular hyperplasia was found in 1(2.5%) patient each out of 40 patients. These two female patients were taking OCP for long duration.
B. Follow-up
Hepatocellular carcinoma and metastatic carcinoma all were treated conservatively and referred to surgery and oncology department. Hydatid cyst case were treated with albendazole and referred to surgery. Liver abscesses and benign liver SOL were followed up in medicine department. These patients were followed up at 1, 2, 4 and 6 months interval with complete blood count, liver function test and USG. Patients of Focal nodular hyperplasia, heamangioma, adenoma and simple cyst were asymptomatic.
Pyogenic abscess: Among 6 patients of pyogenic abscess 4 patients responded with broad spectrum antibiotic therapy and 2 patients responded with broad spectrum antibiotic and therapeutic aspiration. Clinically all patients were improved within 2-3weeks treatment but sonologically resolution of abscess delayed. Sonologically after one month 1(16.67%) patient had complete resolution of abscess cavity and 5 (83.33%) had residual abscess cavity. In 4 month 4(66.67%) patients had complete resolution of abscess cavity and 2(33.33%) patients had residual abscess cavity. .In 6month 5 (83.33%) patients had complete resolution of abscess cavity and 1(16.67%) patient had residual abscess cavity.
A study by K.C.S Sharma D (8) reveals that majority of pyogenic abscess resolved sonologically after 2-18 wks. In our study too majority of abscess resolved within 6month.
Amoebic abscess: All patients of amoebic abscess responded with antiamoebic drugs. They did not require therapeutic aspiration and surgical drainage. Clinically all patients improved within 6-10 days with anti-amoebic drug therapy but sonologically resolution of abscess were delayed. In 6month 3(37.5%) patients had complete resolution of abscess cavity and 5(62.5%) patient had residual abscess cavity In comparison to pyogenic abscess it was seen that complete resolution of abscess cavity delayed in amoebic abscess. A study by Sheen IS, Chien CS, Lin DY, Liaw YF (9) in Chang Gung Memorial Hospital, Taipei, Taiwan shown that pyogenic liver abscesses resolve more rapidly than amoebic abscess. This result is similar with our study.
CONCLUSION
In this study, majority of liver SOL were metastatic carcinoma of liver. Next common SOL is liver abscess. Amoebic liver abscess is more common than pyogenic liver abscess. Liver SOL has various etiology and risk factor. Most of the liver SOL occurs in older age group. Most of them have male preponderance except adenoma, focal nodular hyperplasia. Some of the liver SOL (hemangioma, simple cyst, adenoma, and focal nodular hyperplasia) may be asymptomatic. Majority of liver abscess responded with antibiotics. Clinical response is followed many months later by radiological resolution of abscess.
ACKNOWLEDGEMENT
The authors are grateful to the participants who voluntarily took part in the study. We wish to acknowledge the support provided by the Department of General Medicine, Nil Ratan Sircar Medical College, Kolkata for encouraging research and its publication. Authors acknowledge the immense help received from the scholars whose articles are cited and included in references of this manuscript. The authors are also grateful to authors/editors/ publishers of all those articles, journals and books from where the literature for this article has been reviewed and discussed.
Englishhttp://ijcrr.com/abstract.php?article_id=663http://ijcrr.com/article_html.php?did=6631. Nagorney DM: Benign hepatic tumors: Focal nodular hyperplasia and hepatocellular adenoma. World J Surg 1995; 19:13-18.
2. Ross D, Pina J, Mirza M, et al: Regression of focal nodular hyperplasia after discontinuation of oral contraceptives [letter]. Ann Intern Med 1976; 85:203-4.
3. Mathieu D, Kobeiter H, Maison P, et al: Oral contraceptive use and focal nodular hyperplasia of the liver. Gastroenterology 2000; 118:560-4.
4. Czermak BV, Akhan O, Hiemetzberger R, et al: Echinococcosis of the liver. Abdominal Imaging 2008; 33:133-43.
5. Pickren JW, Tsukada Y, Lane WW: Liver metastasis: Analysis of autopsy data. In: Weiss L, Gilber HA, ed. Liver Metastases, Boston: CK Hall; 1982:2-18.
6. Rockey DC: Hepatobiliary infections. Curr Opin Gastroenterol 2001; 17:257-61.
7. Syed MRR, Nasir I, M Azhar N, M Asif R:Evaluation of liver masses on CT scan: Professional med. journal. sep 2006 13(3) 431-434.
8. European Journal of Radiology. 2010 Apr; 74(1):195-8. doi: 10.1016/j.ejrad.2009.01.017. E.Pub 2009 Feb 12.
9. Sheen IS, Chien CS, Lin DY, Liaw YF: Resolution of liver abscesses: comparison of pyogenic and amebic liver abscesses. Am j tropical med hyg 1989 Apr,40(4); 384-9.
Radiance Research AcademyInternational Journal of Current Research and Review2231-21960975-524171EnglishN-0001November30HealthcarePROSPECTIVE STUDY OF VAGINAL DISCHARGE AND PREVALENCE OF VULVOVAGINAL CANDIDIASIS IN A TERTIARY CARE HOSPITAL
English3438Twinkle N. GandhiEnglish Manish G. PatelEnglish Mannu R. JainEnglishObjective: To study the etiology of vaginal discharge and to detect prevalence of Candida in patients with vaginal discharge from
patients attending at SMIMER medical college, Surat, Gujarat.
Material & Methods: The present study was carried out in the Department of Microbiology, SMIMER medical college, Surat during the period of July 2010 to October 2011. A total 410 suspected cases of vaginal discharge, attending Obstetrics & Gynaecology OPD were included in the study. Detailed history of all patients was taken. All women were subjected to gynecological examination, pH test and Whiff test. Two swabs were collected one for direct microscopy and one for culture and sent immediately
to the laboratory for microbiological examination.
Results: The percentage of Bacterial vaginosis was the highest (47.31%) followed by Candida species (29.75%), E.coli (11.98%), Gram positive cocci (3.41%) and least was Trichomonas vaginalis (1.21%). The age group which was most prone to the infection was 26-35years (41.68%), followed by 15-25 years (40.98%), 36-45 years (13.11%) and least in >46 years (4.23%). Among VVC various associated risk factors observed, like pregnancy (33.6%), OCPS (14.75%), Diabetes mellitus (13.93%) and HIV (5.73%).
Conclusions: In our study the most common pathogen in vaginal infections was Bacterial vaginosis (47.31%) followed by Candida species (29.75%). Distribution of Candida species among different age groups showed the highest incidence in reproductive age group of 26 – 35 years, followed by 16 – 25 years. VVC is more common with risk factors like pregnancy and Diabetes mellitus.
EnglishRTIs, Bacterial vaginosis, VVC, Candida Spp., Vaginal dischargeINTRODUCTION
Vaginitis is the commonest Reproductive tract infections (RTIs) in sexually active females.2, 12 RTIs are the major public health problems among women especially in developing countries.2 WHO estimates that approximately 340 million new cases of curable STIs (Sexually transmitted infections) occur every year and majority of them from developing countries.12,15 Vaginitis is usually characterized by a vaginal discharge and/ or vulvar itching and irritation.4 The three diseases most frequently associated with vaginal discharge are Bacterial Vaginosis (replacement of the normal vaginal flora by an overgrowth of anaerobic microorganisms, myco-plasmas, and Gardnerella vaginalis), Trichomoniasis (T.vaginalis) and Candidiasis (usually caused by Candida albicans).15,4 Even in the modern advances in medicine, there is a rise in the incidence of fungal infections especially those due to Candida species.1 Vulvovaginal candidiasis (VVC) affects up to 75% of reproductive-age women at least once, nearly half will experience recurrences, and 5%–8% have multiple episodes each year.VVC is diagnosed in up to 40% of females with vaginal complaints. 4 ,22Candida species are the normal microbial flora within the gastrointestinal tracts, respiratory tracts, vagina and the mouth.23Under certain conditions, such as prolonged antibiotics therapy, use of contraceptives, malnutrition, pregnancy, diabetes, obesity, tissue transplant, use of immunosuppressant drugs, neutropenia Candida may become pathogenic and cause candidiasis. The majority of these infections are caused by Candida albicans. 3
Diabetes mellitus predisposes individuals to bacterial and fungal infections. Chronic recurring VVC may be a marker of diabetes.18 It is reported that the increase in occurrence of VVC during pregnancy is due to increased levels of hormones such as estrogen and steroid hormones.4,8 If the disease is not treated the baby can get infected (oral thrush) at birth which can be a serious health problem in premature babies.5,19,21 Untreated vaginal infections can lead to pelvic inflammatory disease and infertility.5,19 Sexual intercourse with an infected person is the most common mode of spread of genital candidiasis.12 Clinical diagnosis is based on signs, symptoms and confirmation done by laboratory diagnosis. Vulvar pruritus with vaginal discharge are the dominant feature of vulvovaginal candidiasis.8 The discharge is classically described as thick, adherent, and “cottage cheese-like” with a pH of 4.0 - 4.5.1, 20 To diagnose bacterial vaginosis, Amsel’s criteria is used worldwide. The criteria includes: (i) pH above 4.5; (ii) fishy odour with or without addition of 10 % KOH (Whiff test); (iii) homogenous, milky or creamy vaginal discharge; and (iv) presence of clue cells on microscopic examination. Presence of three out of four criteria is necessary for diagnosis of BV.7, 9 Another criteria for diagnosis of BV is Nugent’s score.6, 17 The prevalence of T.vaginalis ranges from 0.4–27.4% in women. The characteristic frothy, purulent discharge, punctate haemorrhagic areas called “strawberry cervix”, lower abdominal pain and dyspareunia seen in infection with T.vaginalis. 11 Many studies have reported the incidence of specific and non-specific organisms in their population. Gram Positive cocci (group B streptococcus) is a common organism to colonize the vagina. Enterobacteriacea group of organisms are also isolated from culture of vaginal discharge in laboratory. 24
MATERIAL & METHODS
The present study was carried out in the Department of Microbiology, SMIMER medical college, Surat during the period of July 2010 to October 2011 (15/7/2010 to 15/10/2011). A total 410 patients of suspected cases of vaginal discharge, attending Obstetrics &Gynaecology OPD were included in the study. A detailed history was taken with particular reference to name, age, and address, OPD no., presence of predisposing factors, onset and duration of complaints, treatment taken. All patients were asked about a standard questionnaire on their symptoms (vaginal discharge, vulvovaginal itching, vulvovaginal burning sensation, dysuria and dyspareunia). The amount, colour, character and smell of vaginal discharge were noted. Two sterile swabs were used for collection of discharge from lateral and posterior vaginal walls: (i) First swab was used for Amine test, wet mount examination and for gram’s staining. (ii) Second was used for culture on Sabouraud’s dextrose agar, Blood agar and MacConkey’s agar.
Laboratory procedures done:
a) Amine Test: A drop of 10% KOH was added to the vaginal secretions taken on a clean glass slide and fishy odour was noticed.
b) Wet mount examination: The vaginal secretions taken on a clean glass slide and a drop of normal saline added, mounted with a cover slip. No of pus cells and clue cells counted. Candida was identified as highly refractile, round or oval budding yeast cells.
c) Gram’s staining: Smears were prepared by the specimen and was fixed by flaming. Then the slide was stained by Gram’s Method and was examined under microscope for detection of gram positive budding yeast cells with or without pseudohyphae and any bacterial organisms.
d) Culture: Culture was done on Blood agar, MacConkey’s agar and Sabouraud’s dextrose agar. Incubated at 37?C for 24 and 48 hours and colony morphology observed.
e) Final Identification: In case of Candida the species identification was done based on gram staining, germ tube test and inoculation on CHROM agar following standard methods. In case of bacterial pathogen identification was done based on colony morphology, gram stain and biochemical reaction.
RESULTS AND ANALYSIS
Among the 410 vaginal specimens collected from the patients attending Obstetrics & Gynaecology department 26 (6.34%) samples were negative for any pathogen. Among the positive samples the percentage of Bacterial vaginosis was highest (47.31%) followed by Candida species (29.75%), E.coli (11.98%), Gram positive cocci (3.41%) and least was Trichomonas vaginalis (1.21%) (Figure 1). The age of patients was between 19 to 55 years in our study. The prevalence of Candida species was found to be more in reproductive age group, maximum in the age group of 26 to 35 years (41.68%) and 15 to 25 years (40.98%) followed by 36 to 45 years (13.11%) and least in 46-55 years (4.23%) (Figure-2). Among 122 candidiasis case various associated risk factors like Pregnancy (33.60%, 41/122), OCP use (14.75%, 18/122), Diabetes mellitus (13.93%, 17/122) and PLWH (5.73%, 7/122) were observed (Table 1).
Among 122 patients with VVC various symptoms like vaginal discharge were seen in 59.84%(73/122), pruritus in 39.34% (48/122), burning sensation in 32.79%(40/122), dysuria in 19.67% (24/122) and dyspareunia in 31.15% (38/122)(Table 2). Out of total 122 Candida isolates 78 isolates were germ tube test positive and 44 isolates showed germ tube test negative. All yeast isolates were also inoculated on CHROM agar (We had considered CHROMagar as a gold standard method). CHROMagar had shown 81 C.albicans (66.39%) while 41 as non albicans spp. (33.60%) (Table 3).
DISCUSSION
Despite therapeutic advances, vulvovaginal Candidiasis remains a common problem worldwide, affecting all strata of society. Their epidemiological profile varies from country to country and from one region to another within a country depending upon demographic, Socioeconomic and health factors.12 In our study we have found no any pathogen in 6.34% of cases. In Thulkar et al 9 14.36% were of no growth. In our study we have found 11.98% of E.coli that is in correlation with 14% in Puri etal16, while 10% in Fauzia et al10. In our study prevalence of gram positive cocci is 3.41%, while it is 8% in Fauzia et al10. The incidence of bacterial vaginosis in our study (47.31%), while in Puri et al 16 31% and in Thulkar et al 9 39.01%. Among 410 symptomatic women studied, the prevalence of Candida species were 29.75%. The similar pattern of isolation was found in Puri et al16 31% while Fauzia et al 10 found 40%. The incidence of Trichomonas vaginalis in our study is 1.21%, which has good correlation with Puri et al16(2%). The present study was carried out to isolate and characterize the Candida spp. from vaginal discharge of reproductive age. Maximum incidence of VVC in our study was in 26-35 yr. age group 41.68%, other studies showed little higher rate of candidiasis Okungbowa FI et al 8 56.00% and Babin et al2749.58%. VVC is more likely to occur in pregnancy. In our study we found 33.6% patients with pregnancy while similar data in L.B et al25and in Nwadioha et al26 are 44.8% & 40%, respectively. Diabetes mellitus is also another important risk factor in VVC. In present study, we observed 13.93% of VVC with D.M, whereas Nwadioha et al26 observed 7.14%. Other risk factors like HIV/AIDS and OCPs users in our study were 5.73% and 14.75%, respectively while data in Nwadioha et al2612.14% and 15% respectively. In present study Various symptoms of VVC like vaginal discharge(59.84%), pruritus(39.34%), burning sensation(32.79%), dysuria(19.67%) and dyspareunia(31.15%) were found which are in good correlation with Lopes ME et al28 study who found vaginal discharge(57.58%), pruritus(36.36%), burning sensation(45.45%), dysuria(24.24%) and dyspareunia(36.36%). Sensitivity of GTT in our study is 96.2% which is quite comparable with J.E. Hoppe et al13(98.9%) and Arthur E. Crist et al14(94.7%).
CONCLUSION
Proper diagnosis of cases of vaginal discharge is required to know the exact aetiological agent. Vaginal discharge, pruritus, burning sensation, dysuria and dyspareunia are the common complains. Such symptoms may occur due to candidiasis, non candidal pathogen and other factors. This study has shown that Bacterial vaginosis is the most predominant aetiology followed by Candida species. We concluded that discharge and pruritus were the most common symptoms of vulvovaginal candidiasis. Distribution of Candida species among different age groups showed the highest incidence in age group of 16 – 35 years. Candidiasis is more common in pregnancy and diabetic patients. Germ tube test will differentiate between albicans and non-albicans species of Candida. CHROMagar is an easy and reliable method for the identification of various species of Candida.
ACKNOWLEDGEMENT
Authors would like to thank Dean and Medical Superintendent, SMIMER Medical College and hospital for allowing us to carry out this study and for providing the facilities and help. They are also thankful to the Head of Department Obstetrics & Gynecology, SMIMER Medical College and hospital for allowing us to collect the specimens of their patients. Authors would also like to extend their gratitude to authors whose articles are cited and included in the references of the present study. They are also grateful to authors/editors/publishers of all those articles, journals and books from where the literature for this article has been reviewed and discussed.
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