Nocardiasis in patients with HIV infection

The frequency of Nocardia infection in HIV-infected patients has increased during the past few years from 0.3% in 1985 to 1.8% in 1989. Although it is not of great concern as an AIDS-associated infection, the nonspecific clinical presentation in these patients might be confused with other lung infections such as tuberculosis (TB). The mortality rate can be as high as 60%. The authors diagnosed three homosexual men with nocardiasis among 1060 HIV-infected patients (0.2%) in a tertiary care center in Mexico City from 1981 to 1997. The mean age was 32 years. The CD4 count was less than 260 cells/mm3 in all these individuals. The clinical presentations were subacute sinusitis, chronic localized abdominal abscess, and acute disseminated nocardiasis. The respective associated infections were none; TB and cytomegalovirus (CMV); and candidiasis, TB, CMV, Isospora belli, and disseminated Mycobacterium avium complex (MAC). Trimethoprim/sulfamethoxazole (TMP/SMX) was the treatment in all the cases; at the time of this writing, two patients were living and one had died during the acute episode. A literature search uncovered 130 cases of Nocardia infection in HIV patients since 1982. According to the published data and our results, nocardiasis should be suspected in those HIV-infected patients who (1) do not respond to appropriate antituberculous treatment; (2) are intravenous drug users; and (3) develop a characteristic pericardial infection. Finally, adequate surgical or percutaneous drainage of abscesses are extremely valuable for diagnosis and therapy.