Erythema Ab Igne

Key Points
Skin condition which may affect any area of the body
Caused by repeated exposure to heat
Consists of a red, netlike rash which is transient, which may be accompanied by thinning skin, sores, itching or burning

Erythema ab igne is a skin condition which may affect any area of the body. The condition consists of a red, netlike rash in the affected area, which is transient initially but can become semi-permanent with repeated exposure. The rash may be accompanied by thinning skin, changes in skin pigmentation in surrounding areas, itching, burning, and in rare cases, sores may form in the affected area.

Erythema ab igne is caused by repeated exposure to heat which is not enough to burn the skin. Common methods of exposure include repeated use of hot water bottles or heating pads, exposure to automobile heaters, and any profession in which skin is exposed to heat on a regular basis.

Differential Diagnosis (Other conditions with similar appearance)

Acanthosis nigricans
Livedo reticularis
Poikiloderma vasculare atrophicans

Diagnosis
Key Points
Diagnosis based on appearance of the affected area
Skin Biopsy may be performed to confirm diagnosis and rule out other conditions

Erythema ab igne is typically diagnosed based on the appearance of the affected area. Skin biopsy may be performed to confirm the diagnosis and to rule out similar appearing conditions.

Treatment
Mild cases may resolve if heat exposure is avoided
Severe cases may never resolve unfortunately
Treatments to improve appearance of the affected area may be considered

There is no specific treatment for Erythema ab igne except for avoiding heat exposure. In mild cases, avoiding exposure allows the condition to resolve spontaneously within a few months. More severe cases may never resolve, and longstanding lesions with significant skin breakdown or ulceration may carry an increased risk for the formation of skin cancers, such as squamous cell carcinoma. Affected areas should be examined regularly for sores which persist or any lumps that form. Treatments which may approve the appearance of the affected area include laser therapies or the application of topical Tretinoin.