Extensively drug-resistant tuberculosis: epidemiology and management challenges.

Lung Infection and Immunity Unit, Division of Pulmonology and Clinical Immunology & UCT Lung Institute, Department of Medicine, University of Cape Town, Cape Town, South Africa.
Infectious disease clinics of North America (Impact Factor: 2.29). 09/2010; 24(3):705-25. DOI: 10.1016/j.idc.2010.05.001
Source: PubMed

ABSTRACT Widespread global use of rifampin for 2 decades preceded the emergence of clinically significant multidrug-resistant tuberculosis (MDR-TB) in the early 1990s. The prevalence of MDR-TB has gradually increased such that it accounts for approximately 5% of the global case burden of disease (approximately half a million cases in 2007). Eclipsing this worrying trend is the widespread emergence of extensively drug-resistant TB (XDR-TB). This article reviews the insights provided by clinical and molecular epidemiology regarding global trends and transmission dynamics of XDR-TB, and the challenges clinicians have to face in diagnosing and managing cases of XDR-TB. The ethical and management dilemmas posed by recurrent defaulters, XDR-TB treatment failures, and isolation of incurable patients are also discussed. Given the past global trends in MDR-TB, if aggressive preventive and management strategies are not implemented, XDR-TB has the potential to severely cripple global control efforts of TB.

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