A healthy 25-year-old female presented for evaluation of an asymptomatic eruption on both lower legs of 1 to 2 months duration. There is no history of trauma. She has been on the same birth control pill for the last 5 years. She gives no history of cold intolerance or sensitivity. She works as a bank teller.
I asked her if the bank kept the thermostat set at a low temperature, to which she replied that it was so cold where she sat, it was necessary to use a space heater. This confirmed the clinical impression of erythema ab igne (EAI), a skin condition characterized as localized areas of reticulated or net-like erythema and hyperpigmentation due to chronic and repeated exposure to infrared radiation.