Browsing by Author "Coetzee G.J."

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    Drug-resistant tuberculosis epidemic in the Western Cape driven by a virulent Beijing genotype strain
    (2010) Johnson R.; Warren R.M.; Van Der Spuy G.D.; Van Pittius N.C.G.; Theron D.; Streicher E.M.; Bosman M.; Coetzee G.J.; Van Helden P.D.; Victor T.C.
    Temporal analysis of drug-resistant tuberculosis (TB) cases in the Western Cape, South Africa, showed a 1.5-fold increase over a 2-year period, suggesting a doubling time of 8.2 years. This increase was strongly associated with multidrug resistance and the Beijing genotype. Forty-two per cent of the overall increase was due to the Beijing genotype strain R220, suggesting that this strain had evolved unique properties that allowed for both acquisition and transmission of drug resistance. To curb the drug-resistant TB epidemic in this setting, it will be essential to implement rapid diagnostics and efficient infection control measures, improve contact screening and ensure treatment adherence. ©2010 The Union.
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    inhA promoter mutations: A gateway to extensively drug-resistant tuberculosis in South Africa?
    (2011) Muller B.; Streicher E.M.; Hoek K.G.P.; Tait M.; Trollip A.; Bosman M.E.; Coetzee G.J.; Chabula-Nxiweni E.M.; Hoosain E.; Gey Van Pittius N.C.; Victor T.C.; Van Helden P.D.; Warren R.M.
    SETTING: Western Cape and Eastern Cape Provinces, South Africa. OBJECTIVE: To assess the potential association between the evolution of extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis and mutations in the inhA promoter or the katG gene. DESIGN: Analysis of the frequency distribution of isoniazid (INH) resistance conferring mutations in a population sample of drug-resistant isolates of M. tuberculosis. RESULTS: In the Western Cape and Eastern Cape Provinces, the percentage of isolates exhibiting inhA promoter mutations increased significantly from respectively 48.4% and 62.4% in multidrug-resistant tuberculosis (MDR-TB) isolates to 85.5% and 91.9% in XDR isolates. Data from the Western Cape revealed that significantly more XDR-TB isolates showed mutations in the inhA promoter than in katG (85.5% vs. 60.9%, P < 0.01), while the respective proportions were equal for INH-resistant non-MDR-TB isolates (∼30%). CONCLUSIONS: inhA promoter mutations are strongly associated with XDR-TB in South Africa. We suggest that this is due to the dual resistance to ethionamide and (low-dose) INH conferred by inhA promoter mutations. The use of molecular probe assays such as the Geno-Type® MTBDRplus assay, which allows the detection of inhA promoter mutations, could enable treatment regimens to be adjusted depending on the pharmacogenetic properties of the mutations detected. © 2011 The Union.
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    Rise in rifampicin-monoresistant tuberculosis in Western Cape, South Africa
    (2012) Mukinda, Fidele K.; Theron D.; Van Der Spuy G.D.; Jacobson K.R.; Roscher M.; Streicher E.M.; Musekiwa A.; Coetzee G.J.; Victor T.C.; Marais B.J.; Nachega J.B.; Warren R.M.; Schaaf H.S.
    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.
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    The 5-year outcome of multidrug resistant tuberculosis patients in the Cape Province of South Africa
    (1996) Schaaf H.S.; Botha P.; Beyers N.; Gie R.P.; Vermeulen H.A.S.; Groenewald P.; Coetzee G.J.; Donald P.R.
    Little is known about the outcome of multidrug resistant (MDR) tuberculosis (TB) in developing countries. In this study, 443 patients with MDR-TB, defined as resistance to two Or more antituberculosis drugs, were identified over the 2-year period 1987 and 1988 in the Cape Province of South Africa. The 5-year outcome of the 343 (77%) patients that could be traced by questionnaire was evaluated retrospectively during 1992 and 1993 Of these, 240 (70%) were resistant to both isoniazid (H) and rifampicin (R) with or without resistance to other first-line antituberculosis drugs and 103 (30%) were resistant to H or R and/or other antituberculosis drugs. Mortality was 116 (48%) and 28 (27%) in these groups respectively with a significantly greater risk of death in the first group. Only 114 (33%) of all the MDR-TB patients were cured after 5 years, 50 (15%) were respiratory disabled and 44 (13%) were still bacteriology positive. Twenty-four (7%) patients were lost during follow-up. Taking into account the high costs involved in treating MDR-TB patients and the scarce resources available in developing countries, more emphasis should be placed on direct observed therapy to cure newly diagnosed infectious drug sensitive tuberculosis patients, thus preventing MDR-TB rather than treating it.