A boy who spent hours using a laptop directly on his stomach developed a distinctive, net-like skin rash that later worsened and began peeling, highlighting a little-known risk of prolonged exposure to device heat. Doctors identified the condition as erythema ab igne, commonly nicknamed “toasted skin syndrome”. It occurs when the skin is repeatedly exposed to moderate heat that is not intense enough to cause an immediate burn but is sufficient to produce lasting changes in the skin.

How did the boy develop toasted skin syndrome?

According to the case reported by University Hospitals of Leicester NHS Trust, the child was being homeschooled and reportedly used a laptop for as long as eight hours a day.

He often rested the computer directly on his abdomen, including while the device was charging. The prolonged, close contact exposed the same area of skin to heat for extended periods.

The rash initially caused concern because doctors considered whether it could be linked to an underlying medical problem. Blood tests and scans, however, did not identify the suspected cause.

When the boy returned to hospital about two weeks later, the rash had spread and the affected skin was peeling. Doctors then looked more closely at his daily habits and discovered the prolonged laptop exposure.

What is erythema ab igne?

Erythema ab igne is a skin reaction caused by repeated exposure to heat, particularly infrared radiation. It typically appears as a reddish, brown or darker rash arranged in a reticular, or net-like, pattern.

The condition has been recognised for centuries. It was once commonly associated with people who sat close to fireplaces, heaters or other sources of sustained warmth.

Today, the heat source can be more modern. Hot-water bottles, heating pads, heated car seats and laptop computers have all been reported as potential triggers when they repeatedly warm the same patch of skin.

Why does the skin turn into a fishnet-like pattern?

The characteristic pattern develops because prolonged heat exposure affects small blood vessels in the skin.

Early on, the area may simply appear red. With repeated exposure, pigmentation can develop and become more pronounced. In more advanced cases, the skin may become thinner or develop other structural changes.

Unlike an ordinary thermal burn, erythema ab igne can develop without the intense heat, blistering or immediate pain associated with a conventional burn.

That can make it particularly easy to overlook. A laptop may feel comfortably warm rather than dangerously hot, yet repeated exposure in exactly the same place can still injure the skin over time.

Is toasted skin syndrome dangerous?

In many cases, stopping the heat exposure allows mild redness to gradually improve. However, pigmentation can persist for months or even years, particularly after prolonged exposure.

Severe or longstanding cases can cause skin thinning and, rarely, ulceration. Medical references also note a small but important risk of skin cancer, particularly squamous cell carcinoma, developing in chronically affected skin. Persistent sores or a new lump within the affected area should therefore be medically evaluated.

That does not mean ordinary laptop use causes skin cancer. The concern is associated with repeated, chronic heat exposure and persistent skin damage.

How can you prevent laptop-related skin damage?

The simplest precaution is to avoid resting a laptop directly against bare skin for long periods.

Using the device on a desk, table or other hard surface allows heat to dissipate more effectively and keeps the warm underside away from the body. A suitable laptop stand can also improve airflow and reduce direct contact.

People who regularly notice a persistent red, brown or net-like patch where a heated device rests should stop the exposure and have the area assessed by a healthcare professional, particularly if the skin becomes painful, thickened, ulcerated, crusted or develops a persistent lump.

The takeaway

“Laptop burn” does not always look like a burn. Erythema ab igne can develop gradually from repeated exposure to relatively low levels of heat, leaving behind the telltale net-like pattern associated with toasted skin syndrome.

The condition is uncommon, but the underlying lesson is straightforward: warmth that feels harmless can still become a problem when it is repeatedly concentrated on the same area of skin for hours at a time.

Fact-checking note: The medical term for “toasted skin syndrome” is erythema ab igne. The condition is well documented as a reaction to chronic local heat exposure, including from laptop computers. The cancer risk is considered uncommon and is associated mainly with longstanding, severe or persistent lesions rather than routine laptop use.