Abstract

THE STUDY OF DIAGNOSTIC VALUE OF PCR BIOPSY OF THE PLEURA AND THE PLEURAL FLUID PCR IN THE DIAGNOSIS OF PLEURAL TUBERCULOSIS

ABSTRACT

Background: The main cause of pleural tuberculosis is treatable educative pleural effusion. Mortality and morbidity can be reduced by rapid diagnosis of tuberculosis in patients. Definite diagnosis of pleural tuberculosis is depending on acid fast bacilli in sputum or pleural biopsy or a positive culture. Pleural tuberculosis bacilli contain a small number and to prove it is necessary to culture and this will take a long time about 8 weeks. The time required for detecting microorganisms, can be reduced by PCR diagnostic method. Objective: This study was conducted to diagnose better laboratory the tuberculosis pleural effusions. Material and method: In this descriptive-analytical study, 80 patients with exudative pleural effusion with predominance of lymphocytes were evaluated for tuberculosis in the internal ward of Zahedan Ali Ebn Abi Taleb hospital. PCR fluid biopsy and pleural biopsy were carried out using IS6110 primer in both groups who were suffered from tuberculosis and non tuberculosis. The aim of this study was to identify sensitivity and specificity of the PCR method in the diagnosis of lung tuberculosis. Results: Among of patients entered the study, 28 of them had pleural TB and 52 TB. Tuberculosis rejected based on the results of different cultures, smearopathology of pleural biopsy specimens and disease process. PCR result from tuberculosis patients was positive in 13 cases with pleural fluid and in 17 cases of pleural biopsy. Sensitivity and specificity of PCR pleural fluid, were 46 / 4% and 86 / 5% respectively with positive predictive value of 65/ 0% and negative predictive value of 75 / 0% whereas the PCR biopsy pleural sensitive in the diagnosis of TB was 60 / 7% and specificity was 67/ 3% with positive predictive value of 50 / 0% and negative predictive value of 76 / 0% respectively. Conclusion: The result of this study indicated that PCR results may help physicians to diagnose and treat early tuberculosis. PCR biopsy of pleura is more sensitive than PCR pleural fluid, but this method has limitations such as cost and technological difficulties and do not replace with procedures such as biopsy and culture that these both methods are necessary too.

Keywords: PCR, Biopsy, Tuberculosis.