Age-related prevalence and antibiotic resistance of pathogenic staphylococci and streptococci in children with infected atopic dermatitis at a single-specialty center.

Background: Skin staphylococci and streptococci are known to exacerbate atopic dermatitis, but the prevalence changes that occur with age are unknown. This study examined the age-related prevalence and antibiotic resistance of these pathogenic bacteria in children with atopic dermatitis and suspected skin infections.

Observations: Medical records of 150 children with atopic dermatitis referred to a regional center, who had skin swabs taken for suspected infection, were studied retrospectively. All patients carried Staphylococcus aureus. The prevalence of methicillin sodium-resistant (P =.05) and fusidic acid-resistant (P =.001) S aureus tripled from infancy to school age. Lancefield groups A and G streptococci were the other pathogens found. The prevalence of group A streptococci was highest in children aged 3 to 6 (53%), compared with 11% of infants and 21% of patients aged 9 to 16 (P =.002).

Conclusions: Significant differences in the age-related prevalence of group A streptococci skin carriage and antibiotic resistance of S aureus isolates occurred in this group of children with atopic dermatitis and suspected skin infections. Skin swabs to determine bacterial type and antibiotic sensitivities provide an important guide to antibiotic prescribing in these children.