Treatment of experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus with a biodegradable system of lactic acid polymer releasing pefloxacin.

A novel biodegradable system of D-,L-dilactide delivering pefloxacin was implanted in 104 rabbits with experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA), 26 serving as controls. Animals were killed on each third day and viable bacterial counts and levels of pefloxacin in bone tissue were determined. A 99. 9% decrease in viable count of bacteria was achieved by day 12 and complete bacterial eradication on day 33. Pefloxacin was released gradually, reaching its peak on day 15 at levels 100 times the MIC of pefloxacin for MRSA. The biodegradable system described may have a future role in the therapeutic approach to osteomyelitis.