False Positive Rifampicin Resistance among HIV Patients attending Bahati Comprehensive Care Centre, Nairobi, Kenya

Abstract

Introduction: Tuberculosis is a chronic airborne and infectious disease which remains a leading cause of death in people living with Human Immunodeficiency Virus (HIV). Globally in 2018, there were 251,000 documented cases of death in HIV positive people. Timely diagnosis of tuberculosis and detection of drug resistance to TB drugs in such patients remains a challenge because of non specific presentation and disseminated nature of the disease. GeneXpert MTB/RIF assay is a molecular technique capable of simultaneously diagnosing tuberculosis and providing susceptibility status of rifampicin which is a surrogate marker of multidrug resistant tuberculosis. Despite the improved detection capacity in both tuberculosis and rifampicin susceptibility status previous studies have reported on false positive rifampicin resistance associated with Xpert MTB/RIF assay.Objective: This study sought to determine the prevalence of false positive rifampicin resistance among HIV patients attending Bahati comprehensive care centre. Materials and Methods:In a seven month period a retrospective cohort study was conducted among consented 346 people living with human immunodeficiency virus (HIV) attending a comprehensive care centre in Nairobi, Kenya. Detection and isolation of Mycobacterium tuberculosis from patient sputa was done using Xpert MTB/RIF assay and BACTEC MGIT 960 machine, on the other hand first line drug susceptibility testing was done by use of BACTEC MGIT 960 machine. All collected data was analyzed using Statistical Package for the Social Sciences (SPSS) version 20.0.Results: Of the 72(93.5%) Xpert MTB/RIF assay culture positive isolates subjected to drug susceptibility, results revealed 4(6.5%) and 1(10%) false rifampicin resistant cases in the non isoniazid preventive therapy and isoniazid preventive therapy (non-IPT and IPT) arms respectively; OR=1.583[95% C.I= 0.159-15.813]; P=0.538. There were no significant differences regarding false rifampicin resistant