Molecular Epidemiology, Drug Susceptibility and Economic Aspects of Tuberculosis in Mubende District, Uganda

Adrian Muwonge,Clovice Kankya,Jacques Godfroid,Tone B Johansen,Berit Djønne,Willy Ssengooba,Demelash Biffa,Eystein Skjerve,Sydney Malama

doi:10.1371/journal.pone.0064745

Abstract

BackgroundTuberculosis (TB) remains a global public health problem whose effects have major impact in developing countries like Uganda. This study aimed at investigating genotypic characteristics and drug resistance profiles of Mycobacterium tuberculosis isolated from suspected TB patients. Furthermore, risk factors and economic burdens that could affect the current control strategies were studied.MethodsTB suspected patients were examined in a cross-sectional study at the Mubende regional referral hospital between February and July 2011. A questionnaire was administered to each patient to obtain information associated with TB prevalence. Isolates of M. tuberculosis recovered during sampling were examined for drug resistance to first line anti-TB drugs using the BACTEC-MGIT960TMsystem. All isolates were further characterized using deletion analysis, spoligotyping and MIRU-VNTR analysis. Data were analyzed using different software; MIRU-VNTR plus, SITVITWEB, BioNumerics and multivariable regression models.Results M. tuberculosis was isolated from 74 out of 344 patients, 48 of these were co-infected with HIV. Results from the questionnaire showed that previously treated TB, co-infection with HIV, cigarette smoking, and overcrowding were risk factors associated with TB, while high medical related transport bills were identified as an economic burden. Out of the 67 isolates that gave interpretable results, 23 different spoligopatterns were detected, nine of which were novel patterns. T2 with the sub types Uganda-I and Uganda-II was the most predominant lineage detected. Antibiotic resistance was detected in 19% and multidrug resistance was detected in 3% of the isolates.ConclusionThe study detected M. tuberculosis from 21% of examined TB patients, 62% of whom were also HIV positive. There is a heterogeneous pool of genotypes that circulate in this area, with the T2 lineage being the most predominant. High medical related transport bills and drug resistance could undermine the usefulness of the current TB strategic interventions.

Highlights

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a major global public health problem regardless of the modern diagnostics, chemotherapy and vaccines [1] [2]
Studies carried out in Taiwan and Nigeria showed that active TB was predominant among smokers resulting in more case fatalities as compared to nonsmokers [8,9]
M. tuberculosis was isolated from 21% of the patients, 62% of whom were HIV positive

Summary

Introduction

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a major global public health problem regardless of the modern diagnostics, chemotherapy and vaccines [1] [2]. Case fatality rates among HIV infected patients are extremely high, and can be up to 40% in sub Saharan Africa [4,5]. Uganda is ranked 16th among the 22 countries with the highest TB burden, with an incidence of 299 and a mortality rate of 84 cases per 100,000 per year [6]. Studies carried out in Taiwan and Nigeria showed that active TB was predominant among smokers resulting in more case fatalities as compared to nonsmokers [8,9]. Tuberculosis (TB) remains a global public health problem whose effects have major impact in developing countries like Uganda. Risk factors and economic burdens that could affect the current control strategies were studied

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