Tuberculosis chemoprophylaxis.

The incidence of tuberculosis in the United States, after decreasing for many years, has recently begun to climb at an alarming rate. This rise is due mainly to excess cases in high-risk groups including human immunodeficiency virus-infected patients, the elderly, the foreign born, and the homeless. In the United States tuberculosis has been associated with a 10% mortality despite adequate treatment. The tuberculin skin test is a safe and inexpensive test for detecting tuberculous infection. To improve its predictive value the diagnostic criteria for classifying a positive reaction have recently been revised. High-risk populations should be screened to identify those persons who would most benefit from preventive treatment. Isoniazid therapy taken for 6 to 12 months is a safe and highly effective means of preventing tuberculous infection from developing into active disease. The most worrisome toxicity of isoniazid, fatal hepatitis, is extremely rare; when patients are monitored closely the incidence of death from hepatotoxicity is less than 0.01%.     

Tuberculosis and nonsteroidal anti-inflammatory drugs.

In 1980 and 1982 two case reports documented reactivation of pulmonary tuberculosis in patients who had used nonsteroidal anti-inflammatory drugs (NSAIDs). A case-control study was designed to test the hypothesis that such an association does exist. Data for 38 patients were obtained from the patients'' family physicians, and each patient was matched with a control from the same practice for age, sex, race and length of time in that practice. A statistically significant relation was found between the reactivation of tuberculosis and the use of NSAIDs. However, further research is imperative to determine whether the association is direct, indirect or secondary to an unknown factor. Physicians should keep in mind that NSAIDs are potent anti-inflammatory agents and may thus activate, spread and mask infections.