A 20-year-old man presented with a well defined, brown, mildly erythematous, reticulated patch lesion on his left thigh (Figure). Although livedo reticularis could be suggested, the clinical presentation was in keeping with erythema ab igne.
On questioning, the patient described the frequent use of a laptop on his thighs, with the heat source on the left side. Erythema ab igne can be precipitated by any heat source (eg, hot water bottles, heating pads). We recommended that he cease using the laptop directly on his lap or place the laptop on a hard surface.
Clinicians should be aware of this condition to avoid unnecessary medical examinations, and users of laptops should be advised about the effect of heat on their skin.
- Niranthari Chinniah1
- Pablo Fernández-Peñas2
- Skin and Cancer Foundation Australia (Westmead), Sydney, NSW.