Risk factors for erysipelas of the leg (cellulitis): case-control study.

OBJECTIVE To assess risk factors for erysipelas of the leg (cellulitis). DESIGN Case-control study. SETTING 7 hospital centres in France. SUBJECTS 167 patients admitted to hospital for erysipelas of the leg and 294 controls. RESULTS In multivariate analysis, a disruption of the cutaneous barrier (leg ulcer, wound, fissurated toe-web intertrigo, pressure ulcer, or leg dermatosis) (odds ratio 23.8, 95% confidence interval 10.7 to 52.5), lymphoedema (71.2, 5.6 to 908), venous insufficiency (2.9, 1.0 to 8.7), leg oedema (2.5, 1.2 to 5.1) and being overweight (2.0, 1.1 to 3.7) were independently associated with erysipelas of the leg. No association was observed with diabetes, alcohol, or smoking. Population attributable risk for toe-web intertrigo was 61%. CONCLUSION This first case-control study highlights the major role of local risk factors (mainly lymphoedema and site of entry) in erysipelas of the leg. From a public health perspective, detecting and treating toe-web intertrigo should be evaluated in the secondary prevention of erysipelas of the leg.