Introduction. Atopic dermatitis (AD) is a chronic residive inflammatory skin disease which affected approximately 20% in children. Bacterial infection is common in AD patients and correlates directly with AD severity.

Objectives. To evaluate prevalence of bacterial skin infection in AD patients and its relation with severity of AD. And also to study bacteria that usually caused infection in AD and its antibiotic sensitivity.

Methods. A cross sectional study conducted in 86 children and adolescents with AD in Helvetia Community Health Center Medan from March 2016 until February 2017. Index of SCORAD was used to evaluate the severity of AD. Lesional and non-lesional skin were swabbed to take sterile culture. All bacteria isolates were noted and tested for antibiotic sensitivity. Data analysed using Chi-Square and Mann Whitney test with 95% CI. P value <0.05 was considered statistically significant.

Results. Fifty six AD patients (65.1%) were bacterial infected. There was significant association between severity of AD and bacterial infection (p = 0.006). Staphylococcus aureus (S. aureus) was the leading isolate from all degrees of AD severity. Isolated S. aureus were sensitive to amoxicillin-clavulanate (93.3%), clindamycin (90%), erythromycin (90%), and gentamicin (90%). While sensitivity to tetracycline were low (20%).

Conclusion. Prevalence of bacterial infection in AD was 65.1% and the most common isolates was S. aureus (34.8%). It was associated with severity of AD. Staphylococcus aureus were sensitive to amoxicillin-clavulanate, clindamycin, erythromycin, and gentamicin, and were likely to be effective as treatment in infected AD.

Keywords. Atopic dermatitis, S. aureus, antibiotic sensitivity test