Molecular epidemiological analysis of methicillin-resistant Staphylococcus aureus isolates from Chinese pediatric patients.

To investigate the molecular epidemiological analysis of methicillin-resistant Staphylococcus aureus (MRSA) isolates from five pediatric hospitals in China. Seventy-three MRSA isolates were analyzed by a combination of different genotyping methods, including multilocus sequence typing (MLST), SCCmec and spa typing. Panton-Valentine Leukocin (PVL) gene was also detected. The prevalent strains were ST239-MRSA-III and ST1-MRSA clones in the northern region; ST239-MRSA-III, ST910-MRSA-IV and ST88-MRSA in the eastern region; and ST59-MRSA in the southern region. Only the ST910-MRSA-IV clone has been found in China until now, and it is closely related to ST30-MRSA-IV. All MRSA isolates were found to be resistant to penicillin and azithromycin, and multidrug resistance was observed. The cases of necrotic pneumonia, severe skin and subcutaneous tissue infection and lymphadenitis resulted from PVL gene-positive MRSA. There were several novel genetic types of MRSA. Antimicrobial susceptibility tests showed high resistance of many antimicrobials and multiple drugs.