Antimicrobial susceptibility of potentially pathogenic halophilic vibrios isolated from seafood

Susceptibility patterns to 27 antimicrobial agents and beta -lactamase prod uction were investigated in potentially pathogenic halophilic vibrios from seafood. The effect of salinity on the response to the drugs in vitro was a lso studied. All isolates were uniformly sensitive to choramphenicol, imipe nem, meropenem but resistant to lincomycin. All were highly sensitive to ox olinic acid, trimethoprim-sulphamethoxazole, doxycycline, flumequine, cefot axime, nalidixic acid and ciprofloxacin. Some strains of V. harveyi, V. alg inolyticus and V. parahaemolyticus apparently had mechanisms of resistance to several beta -lactam antibiotics other than by the production of beta -l actamases. Sixty-nine strains produced penicillinase but a low correlation between beta -lactamase activity and resistance to beta -lactam antibiotics was noted. The salt concentration affected the in vitro susceptibility of halophilic vibrios and the effect of salinity depended on both the individu al strains and the antimicrobial tested. (C) 2001 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved.