Determinants of severity for superficial cellutitis (erysipelas) of the leg: a retrospective study

BACKGROUND: Superficial cellulitis (erysipelas) of the leg is a frequent infectious disease with a favorable outcome, whereas some patients present a serious disease. The determinants of severity for superficial cellulitis (erysipelas) of the leg have not yet been clearly established. In order to determine the characteristics of patients presenting with severe superficial cellulitis of the leg, we analyzed patients with favorable and unfavorable outcome. METHODS: The records of 167 patients referred to Rouen University Hospital for non-superficial cellulitis of the leg were analyzed. Two severity groups of patients were retrospectively defined. Patients in the severe group either died secondary to infection during hospital stay or were hospitalized for a duration at least equal to the 90th percentile (i.e., >21 days of hospitalization). The remaining patients were considered as presenting with non-severe cellulitis. Potential determinants of severity were analyzed by univariate and multivariate analysis based on logistic regression. RESULTS: From univariate analysis, the following general factors were positively associated with severity: advanced age, arterial hypertension, diabetes mellitus, elevated leukocytosis, and elevated neutrophilia. The local factors associated with severity were ulcer of the leg and arteriosclerosis obliterans of the leg. From multivariate analysis, only age (P=0.004), diabetes mellitus (P=0.01), and leukocytosis (P=0.04) appeared to be independently associated with severity. A close to significant association was also found with arteriosclerosis obliterans of the leg (P=0.07). Whereas general complications occurred more frequently in the severe group, no such difference was observed for local complications. CONCLUSIONS: Determinants of severity for superficial cellulitis of the leg include high age and associated medical conditions. Aged patients and patients with diabetes mellitus, elevated leukocytosis, or possibly arteriosclerosis obliterans of the leg should preferably be hospitalized for specific care of associated conditions to avoid the occurrence of general complications.