Staphylococcus aureus nasal isolates may have the same genetic profile in atopic dermatitis paediatric patients and their close contacts.

Atopic dermatitis (AD) is a chronic skin disease that affects up to 20 % of the paediatric population worldwide. Staphylococcus aureus colonizes anterior nares and can be transmitted in the home environment, aggravating AD. This study aimed to detect S. aureus from nares of AD patients and their family contacts, as well as to evaluate the antimicrobial resistance, virulence and clonality of these isolates. Among the 48 family groups investigated, 30 groups were selected, as both the child and his/her respective contact had methicillin-sensitive S. aureus (MSSA) (24 cases; 54 MSSA isolates) or methicillin-resistant S. aureus (MRSA) isolates (6 cases; 13 MRSA isolates). All MRSA isolates carried SCCmec IV. S. aureus carrying PVL genes were detected in 60 % of patients. Pulsed-field gel electrophoresis (PFGE) analysis was performed for 31 isolates from 15 family groups: all 6 with MRSA and 9 with MSSA isolates. Similar genotypic profiles between isolates from patients and their family contacts were noted in 10 (66.6 %) family groups, 5 (83.3 %) of the MRSA family groups and 5 (55.5 %) of the MSSA family groups, indicating that the pathogen was transmitted through family contacts.