A case of erythema ab igne with histopathological features resembling keratosis lichenoides chronica.

This case describes a pediatric patient with a history of ichthyosis vulgaris and global anhidrosis who was diagnosed with erythema ab igne (EAI), a rare dermatosis resulting from chronic heat exposure. After developing progressive, reticulated brown patches on his extremities and abdomen, extensive diagnostic investigations were conducted to rule out autoimmune, vascular, and genetic etiologies. Bloodwork was unrevealing and biopsies showed histologic features closely resembling keratosis lichenoides chronica. Ultimately, after discovering the patient had prolonged exposure to a space heater, the diagnosis of EAI was made. This case underscores the diagnostic challenges in pediatric EAI cases and emphasizes the importance of careful history taking as part of a comprehensive evaluation.