Extrapulmonary Tuberculosis: A Review

The increase in cases of tuberculosis that has occurred with the increasing number of individuals infected with the human immunodeficiency virus (HIV) has focused attention on the problems in diagnosing and treating tuberculosis. While it is primarily considered a pulmonary disease, tuberculosis has the potential to infect almost every organ system via lymphohematogenous dissemination during the initial pulmonary infection. Since 1984 the incidence of extrapulmonary tuberculosis has increased at an even faster rate than that of pulmonary tuberculosis. Extrapulmonary tuberculosis is considered a diagnostic criterion in the case definition of the acquired immunodeficiency syndrome. Immunocompromised individuals, such as patients with HIV, are at increased risk for extrapulmonary tuberculosis. The clinical manifestations are often nonspecific and insidious, and diagnosis may be delayed for years. Cases of miliary and meningeal tuberculosis are an exception, and they often constitute medical emergencies. Tuberculosis skin tests should be performed on all individuals suspected of having tuberculosis, but a negative test result does not exclude the diagnosis. Chest roentgenograms will often show signs of old or active pulmonary tuberculosis. Microscopic examination and culture of infected body fluids and/or tissue are necessary for definitive diagnosis. Treatment is with standard antituberculous medications. Short-course therapy (6 or 9 months) is probably adequate in most patients with extrapulmonary tuberculosis, but patients with human immunodeficiency viral infection need longer treatment. Extrapulmonary tuberculosis is a persistent problem in the United States and will become more prevalent as the number of patients with HIV increases. A high index of suspicion is needed to diagnose and treat extrapulmonary tuberculosis in a timely and health-preserving manner.