The possible role of quinolones in yersiniosis.

The in vitro susceptibility of 135 strains of Yersinia enterocolitica was tested by agar dilution. About 85% of the strains were susceptible to trimethoprim (1 mg/L), tetracycline (4 mg/L), chloramphenicol (4 mg/L) and cefuroxime (8 mg/L); 90 to 100% to piperacillin (16 mg/L), cefotaxime (8 mg/L) and gentamicin (1 mg/L); 100% to ciprofloxacin (less than or equal to 0.016 mg/L), ofloxacin (0.06 mg/L) and pefloxacin (0.12 mg/L). The outcome of 88 patients, treated for various forms of yersiniosis, showed 15% failure for trimethoprim or co-trimoxazole and tetracycline and 70% failure for cephalosporins and aminoglycoside-beta-lactam combinations. Four patients were successfully treated with ciprofloxacin 500 mg orally or 300 mg intravenously administered twice daily for up to 6 weeks.