An Assessment of Relevance of Sputum Sample Examination in Patients with Tuberculous Pleural Effusion

Abstract

Background: Utility of chest-X ray findings as a reference diagnostic modality in cases of tubercular pleural effusion is well acknowledged. In advent of increasing reports, regarding the absence of visible lung lesions among patients suffering with tubercular pleural effusion, reliability on radiographic findings alone is questionable. In this context, need for a more reliable diagnostic tool in addressing this diagnostic challenge arises. Aim: The present study was undertaken to evaluate the relevance and utility of sputum specimen and adenosine deaminase (ADA) level examination in patients with tubercular pleural effusion, having no visible lesions on radiological examination. Materials and methods Methods: A total 81 cases of suspected tubercular pleural effusion were selected from the inpatient wards of a tertiary care hospital, over a period of eight months (May to December, 2013). Sputum and pleural fluid specimens from all these patients were collected for microbiological investigations such as smear microscopy using Ziehl-Neelsen and Auramine-O staining, mycobacterial culture using conventional method. ADA level was also tested from all pleural fluid specimens. Results: Of the 81 cases, culture positivity from sputum specimens was observed among 13 (16.1%), smear positivity from sputum specimens (3, 3.7%) and smear and culture positivity from pleural fluid specimens (1, 1.23%) cases. High levels of ADA, ranging from 115 IU/L to 203 IU/L were observed among (8, 22.2%) subjects. Conclusion: Our study findings suggest the reliability of smear examination and culture from sputum specimens over pleural fluids specimens and also high sensitivity of ADA as a biomarker in the diagnosis of tubercular pleural effusion.

Keywords: Tuberculous pleural effusion, Mycobacterium tuberculosis, Diagnosis, Adenosine deaminase (ADA)