Susceptibility to antimicrobial agents of rapidly growing mycobacteria

: Rapidly growing mycobacteria are often associated with human diseases. We investigated the in vitro susceptibilities of 40 isolates to six antimicrobial agents: 17 Mycobacterium fortuitum, 11 M. chelonae and 12 M. abscessus isolated from several human sources: 29 respiratory secretions, 5 cutaneous abscesses, 4 corneal ulcers and 2 urine samples of patients treated at "Hospital Puerta del Mar" (Cadiz). Susceptibility studies were determined by the broth microdilution method for amikacin, clarithromycin, ciprofloxacin, levofloxacin, imipenem and cefoxitin. Results suggest that amikacin is the most effective antimicrobial agent for treating infections due to rapidly growing mycobacteria. Clarithromycin and imipenem show good activity against M. fortuitum and M. abscessus, but not against M. chelonae. Quinolones are only effective against M. fortuitum. It's important to identify, in rapidly growing mycobacteria infections, the etiologic agent to determine correct treatment.