Laptop heat causing 'toasted skin syndrome' in children, doctors warn

A boy came to the emergency department with a mysterious rash that no one could explain. His parents hadn't noticed any trauma. He had no fever, no weight loss, nothing that pointed to an obvious cause. The doctors ran blood tests and imaging studies, found nothing wrong, and sent him home. Two weeks later he was back. The rash had spread and worsened, the skin tender and peeling in patches. Only then, when someone asked the right question, did the picture become clear: the boy was being schooled at home and spent up to eight hours a day with his laptop resting directly on his bare stomach, usually while the machine was charging.

He had developed erythema ab igne—toasted skin syndrome—a net-like rash that forms from prolonged exposure to low-level heat. The condition has been documented in adults for years, typically appearing on people who use hot water bottles or heating pads regularly. But doctors are now seeing it more often in children, and the culprit is usually the same: electronic devices that generate steady, modest warmth against the skin for hours at a time.

Dr. Mara Znagoveanu, writing in BMJ Case Reports from her position at University Hospitals of Leicester NHS Trust, documented this boy's case as a cautionary example of how easily the syndrome can be missed in younger patients. The initial presentation—spontaneous bruising, a rash with no obvious source—sent clinicians down a different diagnostic path entirely. Blood work and scans revealed nothing. The boy appeared otherwise healthy. It took a second visit and more careful questioning about heat exposure to arrive at the actual diagnosis.

What makes this case instructive is not just that it happened, but what it reveals about a gap in medical practice. There are currently no formal pediatric guidelines for recognizing or managing erythema ab igne in children. Diagnosis remains clinical, based on history and what the rash looks like. When the heat source is a laptop rather than a traditional heating device, doctors may not think to ask about it. The result is unnecessary testing—blood work, imaging, the full machinery of investigation—when the answer was sitting in plain sight.

Znagoveanu noted that the increasing use of electronic devices, particularly during the pandemic and the shift to home schooling, has created an under-recognized source of the condition in children. "EAI may be overlooked in children, especially when the source of heat is less obvious than the traditional sources," she wrote. The misdiagnosis problem cuts both ways: children with the syndrome may undergo tests they don't need, while the actual cause goes unaddressed.

The good news is that erythema ab igne is usually reversible. Once the heat source is removed, the rash typically improves over weeks or months. In some cases, though, it can leave behind persistent darkening of the skin. In this boy's case, several months after he stopped resting the laptop on his stomach, the rash disappeared entirely—a resolution confirmed during a phone call with his father.

The larger point Znagoveanu makes is about recognition and prevention. Early identification of the syndrome in children, through careful questioning about device use and heat exposure, can spare them unnecessary medical investigations and the anxiety that comes with unexplained symptoms. As more children spend more time with laptops, tablets, and other devices that generate heat, doctors need to add this condition to their mental checklist. A simple question—where is the device resting, and for how long?—could change the course of a child's care.