Risk factors for abscess formation in patients with superficial cellulitis (erysipelas) of the leg.

BACKGROUND: Superficial cellulitis of the leg (erysipelas) is a frequent skin infection. Abscess formation is the most frequent local complication. Determinants of abscess formation in patients with leg cellulitis have not yet been clearly established. OBJECTIVE: To assess the risk factors for abscess formation in patients with leg cellulitis. METHODS: The clinical, biological and bacteriological records of all patients referred to the dermatology department of a university hospital for superficial cellulitis of the leg during a 3-year period were retrospectively reviewed. Using univariate and multivariate analysis, patients' main characteristics at baseline were compared between the group of patients who developed abscess and the group who did not. RESULTS: A total of 164 patients (93 female, 71 male), mean age 65±18 years, were included. Abscess occurred in 13 cases (8%). The following general factors were positively associated with abscess formation: male sex, smoking, alcohol abuse and delayed introduction of antibiotic treatment. Based on multivariate analysis, only chronic alcohol abuse [odds ratio (OR) 4·3, 95% confidence interval (CI)1·08-20·57] and delayed antibiotic treatment initiation (OR 1·4, 95% CI 1·02-2·04) remained independently associated with abscess formation. CONCLUSIONS: Alcohol abuse and delayed initiation of antibiotic treatment are risk factors for abscess formation in patients with cellulitis of the leg. Patients with these predictors must be monitored carefully for abscess formation.