Role of pleural fluid analysis in diagnosis of tubercular pleural effusion

Objective: To evaluate the diagnostic value of pleural fluid analysis in tubercular infection in the people with pleural effusion admitted to our hospital. Material and Methods: All patients aged 22 years and older with clinical and radiographic findings of pleural effusion suspected for tuberculosis admitted to Sir Ganga Ram Hospital (SRGH) between January 1999 to 2005 were evaluated consecutively. Pleural fluid samples were analyzed for level of protein, specific gravity, cell count, differential cell count, bacterial culture and acid-fast bacilli smear. If effusion contains more than 150 WBC/cumm, specimen was cultured on chocolate agar, blood agar and MacConkey's agar. Results: Pleural fluid protein was more increased as compared to the normal (range of 0.68-7.9 gm/dl). Lymphocytes were from nil to 80% and polymorphonutrophils (PMN) from nil to 3200/cumm. Possible gram positive microorganisms were Staphylococcus aureus, Streptococus pneumoniae, Streptococus pyogens and Actinomycetes while possible gram negative microorganism were Hemophilus influenzae, Bacteriolus species, Pseudomonus aureginosa, Klebsiella strains and other enterobacterie. In only a few cases was mycobacterim tuberculosis positively stained. Conclusion: Pleural tuberculosis could be a major cause of pleural effusion and microbiological investigation alone is not enough in diagnosing the diseases.