Extrapulmonary tuberculosis. A review
N. C. Elder
Department of Family and Community Medicine, Oregon Health Sciences University, Portland.
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.
