Abstract

The aim of this study was to determine the contribution of bronchial lavage (BL) and transbronchial parenchymal biopsy (TBB) specimens obtained via Fiberoptic Broncoscopy (FOB) to diagnosis of tuberculosis in smear negative patients suspected of having pulmonary tuberculosis (PTB) according to chest x-rays. Sixty patients whose sputum and/or gastric lavage smears were negative and suspected of having PTB according to chest x-rays were enrolled. Microscopic examination of BL for acid fast bacillus (AFB), histopathological examination, and AFB smear of TBB were performed. Patients were divided into 3 groups as low, intermediate and high risk for PTB according to their chest x-rays. 43 patients were diagnosed PTB: 23 of PTB patients had positive sputum and/or gastric lavage culture, 3 patients had positive BL smear for AFB, 21 patients had positive BL culture, 12 patient positive TBB culture. In addition, 18 of 43 PTB patients had granulomatous inflammation in their TBB specimens. The rapid diagnosis yield of FOB was 48.8%. Fifty percent of the high-risk patients were diagnosed as PTB with TBB while none of the radiological low risk patients were diagnosed. Our results suggest that BL culture increases the bacteriologic diagnosis rate in smear negative patients suspected of having PTB according to chest x-rays, and histopathological examination of TBB specimens might increase the rate of diagnosis, and TBB and BL might be used for rapid diagnosis of smear negative patients suspected of having TB.