English

Abstract

INTRODUCTION : Pleural effusion is a collection of fluid in the Pleural space. It is not a disease but rather a complication of an underlying illness. Effusion can occur for a variety of reasons. Common classification systems divide pleural effusions into two categories of (1) Transudative pleural effusions and (2) Exudative pleural effusions. Determining the cause of a pleural effusion is greatly facilitated by analysis of the pleural fluid. Thoracentesis is a simple bedside procedure that permits fluid to be rapidly sampled, visualized, examined microscopically, and quantified. A systematic approach to analysis of the fluid in conjunction with the clinical presentation should allow the clinician to diagnose the cause of an effusion. • A definitive diagnosis is provided by the finding of malignant cells or specific organisms in the pleural fluid, can be established in approximately 25 percent of patients. • Pleural effusion remains undiagnosed after routine tests in pleural fluid in many patients. so, we need a simple and safe investigative tool to evaluate undiagnosed effusion. This study is designed to diagnose the cases of undiagnosed effusions by a simple and safe investigative tool. Pleural fluid accumulates when pleural fluid formation exceeds pleural fluid absorption. Normally fluid enters the pleural space from the capillaries in the parietal pleura and is removed via the lymphatics situated in the parietal pleura. Fluid can also enter the pleural space from the interstitial spaces of the lung via the visceral pleura or from the peritoneal cavity via small holes in the diaphragm. The lymphatics have the capacity to absorb 20 times more fluid than is normally formed. Accordingly, a pleural effusion may develop when there is excess pleural fluid formation (from the interstitial spaces of the lung, the parietal pleura, or the peritoneal cavity) or when there is decreased fluid removal by the lymphatics. AIMS AND OBJECTIVES : 1. To evaluate the role of closed Pleural biopsy in diagnosing exudative effusions not diagnosed by Pleural fluid analysis. 2. To compare the yield of each test (Histopathological examination, Reverse Transcriptase Polymerase Chain Reaction and culture for Tuberculosis by BACTEC) in Pleural biopsy specimens of undiagnosed exudative Effusions. MATERIALS AND METHODS : STUDY DESIGN : This is a Prospective (Observational) study designed to evaluate the role of closed pleural biopsy in undiagnosed exudative Pleural effusion. STUDY CENTER : The study was done at the Department of Thoracic Medicine – Government General Hospital, Chennai. STUDY DURATION : January 2010 to June 2010. STUDY POPULATION : Patients with exudative pleural effusion remain undiagnosed after pleural fluid analysis. Proforma was designed and ethical clearance was obtained. A written informed consent was obtained from all the patients included in the study after explaining in detail the nature and purpose of the study. INCLUSION CRITERIA : Exudative effusion which is negative for Malignant cells, Acid Fast Bacillus, Gram stain and Non Tuberculous culture in Pleural fluid. EXCLUSION CRITERIA : • Exudative effusion positive for Malignant cells, • Exudative effusion positive for Tuberculosis in Pleural fluid Smear, • Exudative effusion positive for Gram stain or Non-Tuberculous Culture, • Parenchymal lesion in the X-ray suggestive of Tuberculosis or Malignancy or parapneumonic effusion, • Uncooperative patients, • Coagulation disorders, • Dry pleural tapping, • Empyema, • Uremia. CONCLUSION : Combination of Histopathological examination, BACTEC culture and Reverse Transcriptase Polymerase Chain Reaction in closed Pleural biopsy has a greater diagnostic yield in diagnosing exudative effusions not diagnosed by Pleural fluid analysis. • Histopathological examination diagnosed 67% of Tuberculous effusion. • Reverse Transcriptase Polymerase Chain Reaction diagnosed 26.1% of Tuberculous effusion. • BACTEC diagnosed 11.8% of Tuberculous effusion. • Histopathological examination diagnosed 70% of Malignant effusion. • 82.3% of Tuberculous cases were diagnosed by combining all three tests. • 82.3% of Tuberculous cases were diagnosed by combining Histopathological examination and Reverse Transcriptase Polymerase Chain Reaction. • Pleural biopsy diagnosed 79% of undiagnosed effusion. • Closed Pleural Biopsy can be used as a easy, quick, cost effective and relatively safe method to diagnose an exudative effusion not diagnosed by pleural fluid analysis.