Perils of Technology – Laptop Induced Erythema Ab Igne (Toasted Skin Syndrome) on Abdomen

Sir,

We live in an era of information-technology. The use of portable computers i.e. laptop has increased exponentially in the last decade. A 40-year-old man, premorbidly healthy, presented with asymptomatic pigmentation on the abdomen which he had noticed 5 days prior. He denied any past history of similar lesions, pruritus, trauma, similar lesions at other sites and fever, or other constitutional symptoms. On examination, there was a reticular, brownish hyperpigmentation, [Figure 1] macular, non-tender, non-blanching discoloration over the abdomen. There was no induration and no evident scratch marks. On questioning, he worked as a software engineer who spent at least 3-4 hours a day since the last four years on laptop. Further enquiry revealed his habit of placing the laptop on the bare skin of his abdomen in supine/reclining position at home. Interestingly, he complained of a burning sensation, on occasions when the laptop was being charged. His haemogram, autoimmune serology and thyroid profile was normal. On clinical grounds, he was diagnosed with erythema-ab-igne (EAI) secondary to laptop use. He was counseled to avoid placing the laptop on bare skin, and his discoloration gradually disappeared over next six months without any other treatment [Figure 2].

Figure 1.

Cutaneous lesions of erythema ab igne over the abdominal wall due to long term laptop use

Figure 2.

Complete resolution of skin lesions after six months

EAI (“redness from fire”), also known as “granny's tartan”, “toasted skin syndrome”,[1]“ephelis-ignealis”, “erythema-a-calore”,[2] refers to a chronic skin condition resulting from prolonged exposure to low grade heat that is insufficient to cause burning.[1] It is a reticular, telangiectatic, pigmented dermatosis due to exposure to infrared radiation.[2] The pattern depends on the direction of radiation and the skin contour. It begins as mild localized erythema progressing to reticulate erythema, hyperpigmentation, telangiectasia, scaling and atrophy. The development of subepidermal bullae has also been reported.[2] They are usually asymptomatic, although pruritus and burning have been reported.[1]

Historically, EAI was found on the shins of elderly folk who sat for hours in front of radiators or open fires. However, it may occur at any age. Recently, it has been reported on the arms and faces of cooks or bakers working over hot stoves, glass blowers, foundry workers, on the limbs of intensive care patients lying on electric heating blankets, in association with electronic devices or heating pillows and on the abdomen/ back due to hot-water bottles applied for chronic pain relief in pancreatitis or gastrointestinal malignancies. A case of generalized EAI has been reported associated with hot bathing. Interestingly, EAI has also been reported in individuals who have been using laptop computers.[1,3] Laptop-induced EAI is due to heat from the optical drive, battery and also due to occlusion of the cooling fan. This heat can achieve an optimum temperature of 50°C due to close approximation with skin when kept over the thigh leading to EIA.[4] As per literature, more than 90% of laptop-induced EAI have been observed on the thighs and legs. One case has been reported over the breast[5] and two cases over the abdomen.[2,4]

EAI can resemble livedo reticularis, livedo racemosa, cutis marmorata, and cutis marmorata telangiectasia.[6] Skin biopsies may demonstrate variable findings, ranging from a sparse perivascular infiltrate in early lesions to epidermal atrophy, telangiectasias, keratinocyte atypia, hemosiderin deposition and increased elastin fibers, in late cases. Since histopathology is nonspecific, it is more helpful to exclude other differential diagnoses (like cutaneous vasculitis) rather than confirmation.[6]

Although EAI carries a favorable prognosis, nonmelanoma skin cancers have been reported.[6] It has been associated with the development of squamous-cell carcinoma, Merkel-cell carcinoma, and cutaneous lymphoma.[1] Hence, if lesions of EAI continue to evolve or ulcerate, biopsy should be performed to rule out malignancy.[6]

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Conflicts of interest

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