Oral ofloxacin versus parenteral imipenem-cilastatin in the treatment of osteomyelitis.

We conducted a prospective, randomized, open-label trial, comparing oral ofloxacin with intravenous imipenem-cilastatin for the treatment of chronic osteomyelitis in order to evaluate the efficacy and tolerance. Hospitalized patients with diagnosis of chronic osteomyelitis and isolation of susceptible organisms to ofloxacin and imipenem/cilastatin were eligible for enrollment. Ofloxacin was administered orally (400 mg every 12 hours), and imipenem-cilastatin was given intravenously (500 mg every 6 hours). Organisms were considered susceptible to ofloxacin when the minimal inhibitory concentration (MIC) was <2 micrograms/ml, and to imipenem-cilastatin when the MIC was <4 micrograms/ml. Thirty-two patients were enrolled, 16 in each group. In the intent to treat analysis 11 (69%) patients in the ofloxacin group and eight (50%) in the imipenem-cilastatin group were cured (p = 0.473; 95% confidence interval of the difference from -14.7% to 52.2%). In the per protocol analysis 10 (91%) patients in the ofloxacin group and seven (70%) in the imipenem/cilastatin group were cured (p = 0.311; 95% confidence interval of the difference from -12.2% to 54%). Our trial suggests that oral ofloxacin is as effective as parenteral therapy with betalactam antibiotics in the treatment of osteomyelitis, which could allow a reduction of the period of hospitalization and economic costs.