Community-acquired skin infections caused by Staphylococcus aureus: What is the role of the Panton-Valentine leukocidin toxin?

The data concerning frequency and relevance of the toxin Panton-Valentine leukocidin (PVL) in skin infections caused by Staphylococcus aureus is controversial. The objective of the study was the identification of the role of the toxin in community-acquired skin infections caused by S. aureus.We performed a retrospective analysis of 112 patients with the diagnosis of skin infections caused by S. aureus. Frequency of PVL was investigated by PCR for the lukSF gene. Risk factors and severity of the disease were analyzed. Furthermore, spa typing was done in 55 of the isolated S. aureus.PVL occurred in 45 % of patients with skin infections caused by methicillin-susceptible S. aureus; methicillin-resistant strains were positive in 63 %. Mean age was 30.9 years in PVL-positive infections and thus statistically highly significantly lower than in PVL-negative infections. There was no correlation between presence of PVL and severity and course of skin infections or presence of special risk factors. The spa types showed a high variability in PVL-positive as well as in PVL-negative strains.In our study the PVL status of S. aureus isolated from skin infections was neither correlated with methicillin-resistance nor with the severity of disease. Remarkably, PVL-positive S. aureus strains appeared to be more frequent in younger than in older patients. Our results demonstrate that routine determination of PVL status is not required since the outcome has no diagnostic or therapeutic consequences in daily dermatological practice.