Contribution of PCR in the diagnosis of extrapulmonary tuberculosis

Extrapulmonary tuberculosis is usually more difficult to diagnose than pulmonary tuberculosis. It often involves inaccessible sites and it is paucibacillary. OBJECTIVE AND METHOD: In this study, we tried to analyze the performance of various bacteriological methods used to diagnose 51 cases of extrapulmonary tuberculosis in an infectious diseases ward. RESULTS AND COMMENTS: The culture was positive for 55% of patients. The new amplification methods used were very disappointing for the testing of nonrespiratory samples. The sensitivity of PCR was 32% compared to that of diagnostic culture which remains the most sensitive reference method. Liquid media allow for rapid growth and limit the contaminations. The combined inoculation of liquid and solid medium increases the sensitivity and helps to identify the pathogen.