Isolation of methicillin-resistant Staphylococcus aureus from nasopharyngeal swabs on admission to a ward for pediatric patients: comparison between 1992-1993 and 1997-1998

Abstract

We studied 2,176 nasopharyngeal swabs obtained from 1,891 children on admission to the pediatric ward at Asahikawa Kosei Hospital from January 1997 to December 1998, and compared the results with the same study from January 1992 to December 1993. Fifty strains of Methicillin-resistant Staphylococcus aureus (MRSA) were isolated from 46 patients. The ages of these patients ranged from 7 days to 17 years and 24 patients were younger than 1 year. Six patients were diagnosed as MRSA infection; acute otitis media in 3, osteomyelitis and bacteremia in 1, staphylococcal scalded skin syndrome in 1, and inflammation in umbilical region in 1. The ratio of MRSA positive to the total specimens significantly increased from 1.25% in 1992-1993 to 2.30% in 1997-1998 (p = 0.011). The ratio of MRSA positive to the total S. aureus positive specimens significantly increased from 10.7% in 1992-1993 to 20.3% in 1997-1998 (p = 0.003). These findings demonstrated that prevalence of MRSA carriers among children is increasing.