Clindamycin treatment of experimental chronic osteomyelitis due to Staphylococcus aureus.

Clindamycin was used alone for treatment of experimental osteomyelitis due to Staphylococcus aureus in rabbits. Treatment with 30 mg/kg of body weight three times a day for 14 days was ineffective in sterilizing infected rabbit bones. In contrast, when given for 28 days, clindamycin sterilized the infected bones of 16 (84%) of 19 rabbits treated. Only one of 14 isolates of S. aureus from rabbits treated for two weeks developed resistance to clindamycin (minimal inhibitory concentration, greater than 100 micrograms/ml); none of three isolates from rabbits in which treatment failed in the four-week treatment group showed resistance to clindamycin. The results of four weeks of treatment with clindamycin for chronic experimental staphylococcal osteomyelitis were significantly better than those obtained with any other single agent used in prior studies and were generally as good as those with combination therapy that included rifampin.