Global Impact of Multidrug-Resistant Pulmonary Tuberculosis Among HIV-Infected and Other Immunocompromised Hosts: Epidemiology, Diagnosis, and Strategies for Management.

Multidrug-resistant (MDR) tuberculosis (TB), or TB caused by strains of Mycobacterium tuberculosis resistant to at least isoniazid and rifampicin, represents a major threat to global TB control. Comprising more than 5% of all TB cases annually worldwide, these cases require treatment duration of 2 years on average with expensive and toxic second-line anti-TB drugs. Cure rates are far lower and mortality far higher than for drug-susceptible TB, particularly if patients are coinfected with HIV. Use of rapid diagnostic tools and assessment of risk factors for MDR TB, as well as rapid initiation of MDR TB treatment as recommended by the World Health Organization, including use of appropriate empiric regimens as necessary, is essential to achieving good outcomes from treatment. Rapid initiation of antiretroviral therapy (ART) for those with HIV coinfection, as well as strategic management of overlapping side effects from ART and first and second-line drugs for treating MDR TB to maintain patients on treatment are critical to patient survival and achieving good treatment outcomes. Employing sensible infection control practices in the context of diagnosis and treatment is essential to reducing transmission of MDR TB strains among patient populations and healthcare personnel.