Treatment and prevention of tuberculosis in HIV-infected persons

The treatment and prevention of tuberculosis in HIV-infected patients present significant new challenges. In patients with drug-susceptible organisms, treatment initially with three- and four-drug followed by two-drug regimens used for 6 to 9 months is efficacious, although there appears to be higher rates of adverse drug reactions than in HIV-negative patients. Treatment of MDR-TB is more difficult, requiring a high index of clinical suspicion and rapid detection and the use of multiple drugs with lower efficacy and greater toxicity than first-line agents. Directly observed therapy is the single most effective public health strategy to ensure completion of therapy and to prevent the emergence of drug-resistant tuberculosis. Isoniazid preventive therapy should be given to HIV-infected patients who are tuberculin positive and considered in selected patients who are anergic. There are many unresolved issues and future needs, including (1) the optimal regimen and duration of therapy for drug-sensitive tuberculosis; (2) the necessity for maintenance therapy following completion of a multidrug regimen; (3) an optimal regimen for treatment of MDR-TB; (4) the duration of isoniazid preventive therapy; (5) efficacy and duration of other preventive regimens, for example, pyrazinamide and rifampin; (6) the need for and choice of drugs for persons exposed to MDR-TB; (7) development of new antimycobacterial agents; and (8) the feasibility of some of these strategies in developing countries, which have the greatest burden of tuberculosis with HIV infection. Ongoing and future studies will address these questions to ultimately improve the treatment and prevention of tuberculosis in the HIV-infected patient.