CHRONIC OSTEOMYELITIS CAUSED BY MULTIRESISTANT GRAM-NEGATIVE BACTERIA- EVALUATION OF TREATMENT WITH NEWER QUINOLONES AFTER PROLONGED FOLLOW-UP

We evaluated ciprofloxacin, ofloxacin and pefloxacin regimens for the treatment of chronic osteomyelitis due to Gram-negative multiresistant organisms. The study was open, nonrandomized and included 28, 21 and 16 patients, respectively. The 4-fluoroquinolone regimens were 1000 mg , 400 mg and 400-800 mg bd, for a mean duration of 137, 163 and 134 da ys, respectively. Pseudomonas aeruginosa was the most common pathogen, isolated in 33 individuals. Patients were followed clinically, bacter iologically and radiologically during treatment and for 2-5 years afte r discontinuation of therapy. Clinical outcome at the end of therapy w as successful in 79%, 81% and 75%, improvement occurred in 11%, 10% an d 19%, and the failure rate was 11%, 10% and 6%, while 11%, 5% and 6% relapsed, respectively. At the end of follow-up the bacterial eradicat ion rate was 68%, 76% and 69%, respectively. Fluoroquinolone resistanc e emerged in 18%, 19% and 13% of ciprofloxacin, ofloxacin and pefloxac in recipients, respectively. The newer quinolones were safe and well t olerated and should be considered as the contemporary treatment of cho ice for chronic Gram-negative osteomyelitis, particularly whenever P. aeruginosa is implicated.