Management of HIV-infected patients with MDR- and XDR-TB in resource-limited settings [Unresolved issues]

The emergence of extensively drug-resistant tuberculosis (XDR-TB) poses a significant public health threat for human immunodeficiency virus (HIV) programmes and tuberculosis (TB) control efforts. Recent reports demonstrate high mortality rates among HIV-infected multidrug-resistant (MDR) and XDR-TB patients compared to those without HIV infection. Transmission of these highly resistant TB strains is occurring both within health facilities and in the community. We review the principles of a sound public health approach to this problem, including early diagnosis, treatment for suspected disease, patient support and adherence and sound infection control measures. In the context of drug-resistant TB, we elaborate on current World Health Organization antiretroviral guidelines addressing management issues related to timing of antiretroviral treatment (ART), drug interactions and drug toxicities among patients receiving both ART and second-line TB regimens. We highlight the important research agenda that exists at the intersection of MDR- and XDR-TB and HIV disease.