Tuberculosis in acquired immune deficiency syndrome.

The acquired immune deficiency syndrome (AIDS) epidemic has resulted in a rising incidence of tuberculosis (TB) in the United States, especially in inner cities where AIDS is prevalent and among human immunodeficiency virus (HIV) infected subpopulations with a relatively high background prevalence of tuberculous infection (ie, intravenous drug abusers, Haitians, blacks). Because M tuberculosis is a relatively virulent organism among the AIDS related infections, TB occurs early (often as a sentinel disease) in the course of progressive HIV-induced immunosuppression. In this setting, TB commonly presents in a disseminated, extrapulmonary, or "unusual" form, and when pulmonary TB occurs, the chest radiographic picture is often atypical. Further, the tuberculin test is falsely negative in more than 50% of cases. A high index of suspicion and an aggressive diagnostic approach is required to avoid missing HIV-related tuberculous disease, which is communicable to the general population and is readily treatable with conventional anti-TB drugs. In order to control the rising incidence of AIDS-related TB, tuberculin skin testing must be performed early for all patients who are either HIV infected or are in high risk groups for HIV infection (while they can still react to tuberculin), and isoniazid prophylaxis carried out for those who are tuberculous infected.