Paediatric community-associated Staphylococcus aureus: a retrospective cohort study.

Aim: We aimed to characterise the demographic and clinical features of paediatric community-associated Staphylococcus aureus (CA-SA) infection. We aimed to identify factors associated with methicillin-resistant S.aureus (MRSA) infection evident at the point of care with the potential to guide antibiotic choice.

Methods: A retrospective chart review in 2008 of CA-SA infections at the Children's Hospital at Westmead (CHW), a 300-bed tertiary paediatric hospital in western Sydney, Australia. We calculate rates of MRSA and perform univariate and multivariate analysis for predictors of MRSA.

Results: Of 431 patients with CA-SA infections, 19.3% were MRSA. In univariate analysis, MRSA was predicted by age greater than 1 year, Aboriginal race, rural/regional residence, previous history of skin and soft tissue infection (SSTI) or a family history of SSTI, at least 48 h of antibiotics active against methicillin-sensitive S.aureus (MSSA), invasive infection and abscess formation. In a multivariate analysis factors that independently predicted MRSA in the entire cohort, and in the non-invasive subgroup included abscess formation, a family history of staphylococcal infection or SSTI, Aboriginal ethnicity, at least 48 h of anti-MSSA antibiotics at presentation, presentation during spring and age greater than 1 year.

Conclusions: One fifth of CA-SA infections at our tertiary paediatric hospital in 2008 were MRSA. Several clinical and demographic factors evident at the point of care were highly significant predictors of CA-MRSA infection.