EPTB diagnosis by GeneXpert MTB/RIF test and its Clinical-epidemiological profile

ABSTRACT

GeneXpert is a novel, automated diagnostic test that can identify Mycobacterium tuberculosis (MTB) DNA and resistance to rifampicin (RIF) rapidly for Extrapulmonary tuberculosis (EPTB). Incidence of EPTB is increasing in low burden settings in comparison to pulmonary tuberculosis (PTB) & EPTB is relatively neglected. Aim: This study is aimed at knowing the incidence of EPTB and rifampicin sensitivity using an automated rapid detection method, GeneXpert. Methods: 271 EPTB positive patients were included in this retrospective study during a period from January to July 2018. Details regarding TB diagnosis, rifampicin sensitivity, nature of the sample and patient details including age, sex, occupation, address, habits, past history of TB, HIV status and other clinically relevant information was obtained from hospital and laboratory registers. Results: Out of 1290 tuberculosis positive patients, 1019 were of pulmonary tuberculosis (PTB) i.e., 78.9% and remaining 271 were of extrapulmonary tuberculosis (EPTB) i.e., 21.1%. 42.4% (115 out of 271) patients were in the age group of 31-40 years. Female predominance was observed in EPTB patients. Among 271 EPTB patients, 122 (45%) were diagnosed as pleural TB, 95 (35%) patients affected by tuberculosis at lymphnodes, 3(1.1%) had meningeal TB, 9(3.3%) EPTB cases were diagnosed from pus samples of various clinical conditions and remaining 42(15.4%) EPTB cases identified from various samples including tissues, genitourinary, synovial fluid, bones & joints. 247 (91.1%) out of 271 EPTB patients clinical samples showed rifampicin sensitive. 12 (9.8%) out of 122 pleural tuberculosis cases and 5 (5.2%) out of 95 TB lymphadenitis cases showed resistant rifampicin. Conclusion: TB can be diagnosed by various methods, among which GeneXpert is a rapid, reliable, easy to operate, automated system. GeneXpert helps physicians by providing rapid diagnosis within 90 minutes, in turn aid to initiate prompt treatment at the earliest.