Methicillin-resistant Staphylococcus aureus producing Panton-Valentine leukocidin as a cause of acute osteomyelitis in children.

Staphylococcus aureus was identified as the cause of acute childhood osteomyelitis in 19 patients. A single clone of community-acquired methicillin-resistant S. aureus (MRSA) carrying the type IV mecA staphylococcal cassette chromosome and the Panton-Valentine leukocidin (PVL) genes was isolated from five patients. Among the remaining 14 patients, two methicillin-sensitive S. aureus (MSSA) isolates were PVL-positive. The maximal erythrocyte sedimentation rate and C-reactive protein values, and the time required for normalisation, were significantly different in patients with PVL-positive strains (MRSA and MSSA), suggesting that the production of PVL is an important factor that contributes to the course of the disease.