Successful treatment with ampicillin and fluoroquinolones of human endocarditis due to high-level gentamicin-resistant enterococci

Two cases of endocarditis, one caused by high-level gentamicin-resistant En terococcus durans and the other by high-level gentamicin- and glycopeptide- resistant Enterococcus faecalis, successfully treated with a combination of ampicillin and a fluoroquinolone are reported. Both strains were susceptib le to ampicillin, Enterococcus faecalis was susceptible to ciprofloxacin an d to ofloxacin, but Enterococcus durans was moderately resistant to these a gents. Microbiological and clinical cure was obtained with a 6-week course of ampicillin plus ciprofloxacin in one case and with ofloxacin in the seco nd case due to intolerance to ciprofloxacin, The efficacy of the treatment was predicted in vitro by time-kill studies and by adequate serum bacterici dal titres.