Erysipelas is a form of cellulitis. It is a bacterial infection affecting the most superficial layers of the skin. Erysipelas is also known as St. Anthony's fire, an accurate description of the intensity of this rash. Erysipelas was a feared disease in pre-antibiotic days, especially in infants.

Streptococcal involvement is unusual in that the infection is localized. Serious epidemics were seen many decades ago, but today the condition is rarely seen.

Causes

Erysipelas may affect both children and adults. The risk factors associated with this infection include a cut in the skin, skin ulcers, and problems with the drainage through the veins or lymph system.

Erysipelas is almost always due to Streptococcus pyogenes, but occasionally, other beta-haemolytic streptococci, or rarely, staphylococci, may be responsible. In adults, Group A streptococcal bacterial infection is the most common and in children Hemophilus influenza bacterial infection is the most common.

In the past, the face was most commonly involved site of infection, yet now accounts for only up to 20% of cases. The legs are affected in up to 80% of cases.

Symptoms

Symptoms may include high fevers, shaking, chills, fatigue, headaches, vomiting, and general illness within 48 hours of the initial infection. Few common sympyoms are:-

An erysipelas skin lesion typically has a raised border that is sharply demarcated from normal skin. The underlying skin is painful, intensely red, hardened (indurated), swollen, and warm.

Facial erysipelas classically involves the cheeks and the bridge of the nose.

Blisters may develop over the skin lesion.

Fever and shaking chills are common.

Treatment

This disease is mainly diagnosed by the appearance of the rash and its characteristics. Blood cultures are unreliable for diagnosis of the disease, but may be used to test for sepsis. Erypsipelas must be differentiated from herpes zoster, angioedema, contact dermatitis, and diffuse inflammatory carcinoma of the breast.

Most streptococcal bacteria causing erysipelas are sensitive to penicillin antibiotics and penicillin, either orally or intravenously (if patient is very unwell), are the antibiotic of first choice. Erythromycin may be used as an alternative in patients with penicillin allergy. Treatment is usually for 10-14 days, and while signs of general illness resolve within a day or two, the skin changes may take some weeks to resolve completely.