Rise in rifampicin-monoresistant tuberculosis in Western Cape, South Africa

Abstract
SETTING: Brewelskloof Hospital, Western Cape, South Africa. OBJECTIVES: To verify the perceived increase in rifampicin monoresistant tuberculosis (RMR-TB) in the Cape Winelands-Overberg region and to identify potential risk factors. DESIGN: A retrospective descriptive study of trends in RMR-TB over a 5-year period (2004-2008), followed by a case-control study of RMR and isoniazid (INH) monoresistant TB cases, diagnosed from April 2007 to March 2009, to assess for risk factors. RESULTS: The total number of RMR-TB cases more than tripled, from 31 in 2004 to 98 in 2008. The calculated doubling time was 1.63 years (95%CI 1.18-2.66). For the assessment of risk factors, 95 RMR-TB cases were objectively verified on genotypic and phenotypic analysis. Of 108 specimens genotypically identified as RMR cases, 13 (12%) were misidentified multidrugresistant TB. On multivariate analysis, previous use of antiretroviral therapy (OR 6.4, 95%CI 1.3-31.8), alcohol use (OR 4.8, 95%CI 2.0-11.3) and age ≥40 years (OR 5.8, 95%CI 2.4-13.6) were significantly associated with RMR-TB. CONCLUSION: RMR-TB is rapidly increasing in the study setting, particularly among patients with advanced human immunodeficiency virus (HIV) disease. Routine drug susceptibility testing should be considered in all TB-HIV co-infected patients, and absence of INH resistance should be confirmed phenotypically if genotypic RMR-TB is detected. © 2012 The Union.
Description
Keywords
antiretrovirus agent, isoniazid, rifampicin, adult, age, alcohol consumption, article, case control study, controlled study, descriptive research, drug resistant tuberculosis, female, genotype, human, Human immunodeficiency virus infection, major clinical study, male, mixed infection, multidrug resistant tuberculosis, Mycobacterium tuberculosis, nonhuman, priority journal, retrospective study, risk factor, South Africa, sputum smear
Citation
International Journal of Tuberculosis and Lung Disease
16
2
196
202