Evaluation of multiple laboratory methods in the diagnosis of extrapulmonary tuberculosis

Introduction: Tuberculosis remains a worldwide public health problem. The emergence of human immunodefi ciency virus infections (HIV) has further complicated the disease burden as it has rapidly increased the risk of pulmonary and extrapulmonary tuberculosis (EPTB). EPTB is an important clinical entity. The precise diagnosis is very important because early detection of cases and effective treatment if instituted at the right time completely cures the patients of the disease. Objectives: To find out sensitivity and specificity of Ziehl-Neelsens staining (ZN), Auramine staining, and rapid slide culture technique (RSC), comparing them with growth on Lowenstein- Jensens medium (ZN) as the gold standard. Materials and Methods: The present study included 66 clinical specimens from patients suspected of EPTB inclusive of HIV-infected patients. They were subjected to ZN and Fluorescent method of staining, culturing by LJ and RSC method, and comparing growth on LJ medium as the gold standard. Results and Conclusion: Mycobacterium tuberculosis was isolated in 24.2%. Nontuberculosis Mycobacterium was isolated in 6% of the 66 samples processed. The highest number of isolation was from lymph node aspirates (83.3%). 2% of the samples were HIV seropositive.