[Clinical and bacteriological aspects of nocardiasis. 9 cases]

Nocardial infection is usually localized in the immunocompetent patient and occurs as an opportunistic disseminated infection in about half of the cases in immunoincompetents patients.

We report a retrospective assessment of 9 cases of nocardial infection diagnosed between January 1991 and February 1994.

Six of the patients were immunodepressed: 3 had a disseminated infection with pulmonary (n = 2), brain (n = 2), skin (n = 3) and/or ocular (n = 1) localizations. There were 3 immunocompetent patients with an isolated local infection: skin and bone mycetoma, knee joint and lung. Diagnosis was made on samples obtained invasively in 7 patients. Nocardia asteroides was isolated in 5 patients, N. farcinica in 3 and N. caviae in 1. These organisms showed in vitro sensitivity to amoxicillin-clavulanic acid 5/9, cefotaxime 5/9 (0/3 for N. farcinica), imipeneme 7/9, amikacin 8/8, minocyclin 5/8, pefloxacin 0/8 and trimethoprime-sulfamethoxazol (TMP-SMX) 3/9. Clinical outcome was favourable in all cases and was not always correlated with laboratory sensitivity.

TMP-SMX remains the reference antibiotic. For one patient, only TMP-SMX (resistant in vitro) was effective; with all the other antibiotic tried (sensitive in vivo) treatment failed.