Clinical Features Associated with Nasal Staphylococcus aureus Colonisation in Chinese Children with Moderate-to-severe Atopic Dermatitis

Introduction: Staphylococcus aureus colonisation/infection is common in children with atopic dermatitis (AD). Materials and Methods: We evaluated the nasal and body swabs of Chinese children with moderate-to-severe AD as assessed using SCORing-Atopic-Dermatitis (SCORAD) score. Swabs were taken from the right nostril, 5 flexural sites (anterior neck, antecubital fossae and popliteal fossae) and the skin area most severely affected (with oozing/crusting) for bacteriologic culture. Results: Fifty-five children (30 males and 25 females) were evaluated. Moderate-to-heavy growth of S. aureus was present in 12 (22%) of the nasal swabs, and in 1 or more flexural swabs of 32 (58%) of these children. Only 7 (35%) out of the 20 patients who had swabs taken from the worst skin area had moderate-to-heavy growth of S. aureus. Significant nasal S. aureus colonisation was associated with higher total (P = 0.029) and objective SCORAD scores (P = 0.040), more extensive disease (P = 0.025), the presence of oozing or crusting (P = 0.023) and higher eosinophil counts (P = 0.038). All specimens of methicillin-sensitive S. aureus were sensitive to cloxacillin and 71% to erythromycin. Methicillin-resistant S. aureus (MRSA), sensitive to vancomycin, was only isolated in 1 patient. Conclusions: In this study, S. aureus is a principal pathogen. Cloxacillin and first-generation cephalosporins have a favourable sensitivity profile even in children with moderate and severe atopic dermatitis. The anterior nares are an important harbour for S. aureus and significant nasal S. aureus colonisation was clinically associated with more extensive lesions and the presence of oozing or crusting.