Kotatsu-induced erythema ab igne

Erythema ab igne is a reticulated, hyperpigmented dermatosis that arises following chronic infrared exposure. It has been reported with prolonged exposure to heating pads or blankets, hot water bottles, heated furniture, laptop computers, prolonged bathing in hot water, open fires, and wood-burning stoves, among others.1-3 It is usually asymptomatic and resolves with discontinuation of the offending heat source. There are several reported cases of neoplastic transformation occurring at the affected site.4,