Rifampicin resistance among individuals with extra pulmonary tuberculosis at tertiary care hospital, Ahmedabad

Abstract

Introduction: Tuberculosis is an infectious disease caused by the Mycobacterium tuberculosis which typically involve lung but can affect other sites called extra pulmonary tuberculosis (EPTB). Common disease manifestations of EPTB include meningitis, lymphadenitis, ocular, oral, pleuritis, pericarditis, peritonitis, cutaneous, musculoskeletal, abdominal, genitourinary, and miliary forms of tuberculosis. EPTB can be either primary (at the site of initial infection) or secondary (disseminated), which usually occurs due to haematogenous or lymphatic spread of bacteria from the primary organ, reactivation of Latent TB Infection (LTBI), ingestion of
infected sputum, or spread locally from adjacent organs. EPTB cases accounted for 16% of the 7.5 million incident cases worldwide in 2019. Cartridge based nucleic acid amplification test (CBNAAT) have high sensitivity in both respiratory and non-respiratory specimens.
Materials and Methods: A laboratory based retrospective observational study. The study was conducted in the department of Microbiology, Narendra Modi medical college, Ahmedabad, Gujarat over a period of one year i.e. from January 2022 to December 2022. The main Aim of study to determine the rate of rifampicin resistant M. tuberculosis among EPTB and to determine the age and gender dependent preponderance of EPTB. A total of 1523 EPTB specimens were received from various clinical sites suspected of EPTB infections. All received EPTB specimens were processed in CBNAAT laboratory with aseptic precautions and tested in Gene Xpert MTB / RIF, according to NTEP guidelines.

Results: Overall isolation rate of Mycobacterium tuberculosis causing EPTB infection was 208 (13.7 %). Among that rifampicin resistant were 23 (11%). EPTB infections were found invarious specimens like pleural fluids 57(15%), FNACs 52 (29 %), pus 50 (54%), gastric
aspirates 34 (5%), CSF 7 (8 %), ascitic fluids 5 (7%), other body fluids 2 (10%) and synovial fluid 1 (25%). In present study rifampicin resistant were seen in females 19 (83%) as compared to male 4 (17%). Age group of 11-20 years - 11 (24%) showed highest rifampicin resistance followed by 21-30 years - 08 (16 %). Rifampicin resistance was highest in “medium” level EPTB load - 10 (21%) specimens of EPTB.
Conclusions: The study shows a high proportion of rifampicin resistance at tertiary care hospital, Ahmedabad. The review showed that the incidence of extra pulmonary Rifampicin Resistance Tuberculosis has continued to become a serious public health problem. Hope thus, this finding could help the programmatic management of the disease within the context of the National TB Control progra (NTEP).