Erysipelas is a skin infection that causes redness, tenderness and pain to the touch, increased warmth and swelling. Erysipelas affects a more superficial area of the skin layers, while cellulitis is a more severe infection affecting deeper layers. Erysipelas is commonly known as St Anthony's fire. It can occur anywhere on the body but is most often seen on the legs. It is a bacterial infection. The entry point is often a break in the skin's integrity, a moist area or wound tissue – for example, it can appear on the leg following a fungal infection between the toes, or on the face after picking at a pimple.
The presence of diabetes, medications that suppress the immune system, or poor skin care are factors that make erysipelas more likely to develop. It can be treated easily and quickly if caught early. If treatment is delayed, or if poor prognostic factors related to the patient are present, the infection can progress and lead to more serious conditions affecting the whole body.