Methicillin-resistant Staphylococcus aureus colonization in inflammatory versus non-inflammatory skin diseases: who should be screened?

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) was prospectively investigated in a dermatology outpatient setting. Swabs were taken from anterior nares, perineum and lesional skin in 229 patients with erosive inflammatory skin diseases (n=88), venous leg ulcers (n=58) or basal cell carcinoma (n=83) and processed by standard methods. The isolated MRSA strains were characterized by pulsed-field gel electrophoresis after digestion with the restriction enzyme SmaI. MRSA carriage was detected in 10/88 patients with inflammatory skin diseases, 5/58 with venous leg ulcers and 0/83 with basal cell carcinoma. Most of the MRSA isolates could be identified as either the Rhine-Hessen epidemic strain or local epidemic strains. None of the isolated strains was resistant to vancomycin, gentamicin or mupirocin. MRSA is uncommon in outpatients in our dermatology clinic; however, the presence of chronic ulcers and erosions was significantly associated with MRSA positivity. Therefore, patients with chronic ulcers and erosions should be screened for MRSA colonization to implement infection control measures.