Determination of theIn VitroSusceptibility of 220Mycobacterium fortuitumIsolates to Ten Antimicrobial Agents

Abstract

The authors investigated the in vitro susceptibility to antimicrobial agents of 220 Mycobacterium fortuitum isolates originating from clinical samples (14) of patients attending the Hospital Universitario de Canarias and Hospital del Tórax, and from environmental sources (206): 3 from sea water, 10 from the water supply and 193 from sewage. The Minimum Inhibitory Concentration (MIC) was calculated using the broth microdilution method with Mueller-Hinton Broth without supplement. Amikacin was the most efficacious antimicrobial agent against all the isolates of M. fortuitum with an MIC which was considerably lower than its critical concentration. The good results achieved with amikacin in vitro are confirmed by those obtained in vivo, with patients infected with M. fortuitum. No significant difference was found in the efficacy of amikacin and ofloxacin against all the isolates assayed.

Atypical Osteomyelitis Caused byMycobacterium chelonae—A Multimodal Imaging Approach

“…It is found in natural and processed water sources and known to be responsible for a distinct number of primary infections of the skin, lung, eyes, and soft tissue [2, 5–7]. …”

Clinical microbiological case: infection imitating lymphocutaneous sporotrichosis during pregnancy in a healthy woman from the south-eastern USA

“…This approach may change in future if a single, highly active antimicrobial agent becomes available [ 22 ]. Several antimicrobial agents are active against the RGM [ 2 ]; a recent in vitro antimicrobial susceptibility analysis showed that amikacin [ 23 ], azithromycin [ 24 ], cefoxitine [ 25 ], ciprofloxacin [ 22,25 ], clarithromycin [ 24,25 ], doxycycline [ 25 ], imipenem [ 25 ] and trimethoprim–sulfamethoxazole [ 25 ] remain active against M. fortuitum . Similarly, no in vitro antimicrobial resistance was seen in the mycobacteria isolated from this patient.…”

Activity of various drugs alone or in combination against Mycobacterium fortuitum

“…Amikacin, a second-line drug for the treatment of M. fortuitum infection, has good bactericidal activity [11,12]; and, interestingly, rifampicin and rifabutin showed good utility when associated with other drugs.…”