Clinical and Epidemiologic Features of Infection With Mycobacterium genavense

Objectives: To characterize clinical and epidemiologic features of infections with Mycobacterium genavense. Design: Case series and case-control studies. Patients with M genavense were compared with two control groups: CD4 controls were matched on the basis of CD4 counts, and Mycobacterium avium-intracellularecomplex controls had disseminated infection with M avium-intracellulare complex. Results: Fifty-four patients with disseminated infections caused by M genavense were found, from Europe (37), North America (15), and Australia (two). All were infected with human immunodeficiency virus. The median CD4 count was 0.016× 10⁹/L (16/mm³) (range, 0.001 to 0.082×10⁹/L. Eighty-seven percent had fever and weight loss, 44% had diarrhea, 43% had splenomegaly, 39% had hepatomegaly, and 72% had anemia. In Swiss university hospitals, M genavense was responsible for 12.8% of nontuberculous disseminated mycobacterial infections in patients with human immunodeficiency virus from 1990 to 1992. The median survival was 190 days after the first isolation of M genavense. Among the patients who had been treated with at least two antimycobacterial drugs for 1 month or more, median survival was 263 days (95% confidence interval, 144 to 382 days), compared with 81 days (95% confidence interval, 73 to 89 days) for those not treated (P=.0009). Survival in patients with M genavense was similar to the survival of M avium-intracellulare complex controls. However, patients with similar CD4 counts (CD4 controls) survived longer (median, 342 days; 95% confidence interval, 269 to 415 days; P<.0003). Conclusions: Infection with M genavense may be responsible for more than 10% of disseminated nontuberculous mycobacterial infections in patients with human immunodeficiency virus infection. Its clinical presentation and response to treatment are similar to those of infection with M avium-intracellulare complex.