Extrapulmonary tuberculosis: an overview

In the 1980s, after a steady decline during preceding decades, there was a resurgence in the rate of tuberculosis in the United States that coincided with the acquired immunodeficiency syndrome epidemic. Disease patterns since have changed, with a higher incidence of disseminated and extrapulmonary disease now found. Extrapulmonary sites of infection commonly include lymph nodes, pleura, and osteoarticular areas, although any organ can be involved. The diagnosis of extrapulmonary tuberculosis can be elusive, necessitating a high index of suspicion. Physicians should obtain a thorough history focusing on risk behaviors for human immunodeficiency virus (HIV) infection and tuberculosis. Antituberculous therapy can minimize morbidity and mortality but may need to be initiated empirically. A negative smear for acid-fast bacillus, a lack of granulomas on histopathology, and failure to culture Mycobacterium tuberculosis do not exclude the diagnosis. Novel diagnostic modalities such as adenosine deaminase levels and polymerase chain reaction can be useful in certain forms of extrapulmonary tuberculosis. In general, the same regimens are used to treat pulmonary and extrapulmonary tuberculosis, and responses to antituberculous therapy are similar in patients with HIV infection and in those without. Treatment duration may need to be extended for central nervous system and skeletal tuberculosis, depending on drug resistance, and in patients who have a delayed or incomplete response. Adjunctive corticosteroids may be beneficial in patients with tuberculous meningitis, tuberculous pericarditis, or miliary tuberculosis with refractory hypoxemia.