Diagnostic yield of GeneXpert in bronchoalveolar lavage in smear-negative pulmonary tuberculosis

Abstract

uberculosis (TB) continues to be one of the major endangering public health issues in the underdeveloped world. Microscopy examination of sputum smears for the revelation of acid-fast bacilli (AFB) and specific mycobacterial cultures have been the cornerstone in the diagnosis of pulmonary tuberculosis for many years. Mycobacterial culture (Löwenstein–Jensen) needs 3-6 weeks to grow. Hence, it cannot direct us to start the initial therapy in spite of being the gold standard and the most specific diagnostic test (Shin et al., 2012). Although sputum examination for acid-fast bacilli (AFB) is simple and economic, only 44% of cases are positive (Shin et al., 2012). In 2015, European Centre for Disease Prevention (ECDC) reported that, in Italy, in 2014, 68.1% of all TB cases were smear-negative (ECDC, 2015). Optimal management and better treatment response are not achieved in active smear-negative pulmonary tuberculosis due to delay in diagnosis and poor microbiological reliability (WHO, 2014).