Role of gene expert in rapid molecular detection of extrapulmonary tuberculosis in tertiary CATE hospital

Kala Yadhav M L, Veena M


Introduction: Tuberculosis, the most common infectious disease with prevalence of 9.6 million globally. Most prevalent (23%) in India. Extrapulmonary tuberculosis (EPTB) accounts for 20% of total burden of tuberculosis. Rapid detection of Mycobacterium Tuberculosis (MTB) is essential for effective disease management. CBNAAT (Cartridge Based Nucleic Acid Amplification Test) or Gene Xpert MTB/RIF assay - novel diagnostic tool to detect MTB and RIF resistance simultaneously. WHO recommends its utility for non-respiratory samples also. Burden of EPTB and drug resistance vary from place to place. Objective: Study was conducted to gather information about burden of disease in our locality and to assesutility of CBNAAT in detecting MTB and rifampicin resistance in suspected EPTB cases. Methods: Retrospective analysis of 281 samples from suspected cases collected in falcon tubes and processed using CBNAAT. Result: Total of 281 extrapulmonary samples received, 67(23.8%) were positive and 214(76.1%) were negative for MTB. Of 67 positives, RIF resistance detected in 1(1.49%) case. Maximum number of MTB detected in the age group 20-30 years (n=23, 34.3%). Among 165 males and 116 females, MTB detected in 44(26.6%) and 23(19.8%) respectively. Out of 281 patients, 24(8.54%) were HIV positive. Of these 24, only 8(33.3%) found positive for MTB. Among 257 non-HIV patients, MTB detected in 59(22.9%). Among different samples received, maximum number were Pleural fluid n=115(40.9%) and Maximum MTB positives found in FNAC samples n=35(52.2%). Conclusion: CBNAAT is a rapid test to detect MTB and rifampicin resistance simultaneously in EPTB and it reduced the treatment abuse in suspected cases.

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