ABSTRACT
Bacteriological examination of sputum is the cornerstone in the diagnosis of pulmonary tuberculosis [PTB] in developing countries. The risk of spread of infection and emergence of drug resistant strains has created the need for rapid, sensitive and specific diagnostic tests. The presence of acid fast bacilli [AFB] was investigated comparatively with the Ziehl-Neelsen [ZN] and the Fluorochrome [FC] staining techniques in order to evaluate them in detecting PTB. A total of 400 specimens obtained from clinically diagnosed PTB cases were analyzed. The culture was used as the "gold standard". Eighty five patients [21.3%] were diagnosed as having tuberculosis [TB] by culture. The positive yield found with the staining techniques was 16% by ZN and 17.8% by FC. The ZN and FC sensitivity and specificity was found to be 62.4%/96.5% and 76%/98.1% respectively. The positive predictive value [PPV] and negative predictive value [NPV] for the two staining techniques was found to be 82.8%/90.5% and 91.5%/94% respectively. In conclusion, our data indicate that the fluorochrome staining method was found to be more efficient and reliable when compared to the Ziehl-Neelsen staining method for the primary diagnosis of tuberculosis