Antibiotic treatment of cutaneous infections with Staphylococcus aureus in patients with atopic dermatitis: current antimicrobial resistances and susceptibilities

Summary Background/aims: Atopic dermatitis (AD) is a common chronic inflammatory skin disease. In many patients, the disease is complicated by enhanced susceptibility to skin infections, especially with Staphylococcus aureus. The aim of this study was to determine the antimicrobial susceptibility of skin‐colonizing S. aureus strains in patients with AD and consecutively to recommend the first‐line antibiotic therapy. Methods: We studied S. aureus‐positive skin swabs (n = 102) from lesional skin of children, adolescents and adults with AD presenting to our inpatient and outpatient departments from January 2005 to June 2006. Results: Antimicrobial susceptibility testing revealed resistance against oxacillin, amoxicillin/clavulanic acid, cephalexin and cefuroxim in 3%, against tetracycline in 17%, against gentamicin in 16%, against erythromycin and clindamycin in 21%, against trimethoprim/sulfamethoxazol in 23%, against levofloxacin in 23%, against fusidic acid in 25%, against fosfomycin in 12% and against rifampicin in 16%. All strains isolated were susceptible to vancomycin. Conclusion: Currently, the first generation cephalosporin cephalexin appears to be the preferential first‐line antibiotic for the treatment of bacterial superinfections with S. aureus in children and adults with AD due to its restricted antimicrobial spectrum to Gram‐positive bacteria and a limited number of Gram‐negative strains. Cefuroxim and amoxicillin/clavulanate, which also showed 3% resistances in our patients, cover a broader range of bacterial micro‐organisms. However, a broader coverage is not required in case of AD, as S. aureus is the most frequent bacterial micro‐organism causing skin infections.