A previously healthy 4-year-old boy presented with a rash on his elbows and knees that over 3 weeks became pruritic and expanded to the posterior cervical region and hands. It appeared during the summer, while frequently wearing a thermal suit. The patient had no systemic symptoms and none of his cohabitants had a rash. Skin examination revealed flesh-colored to mildly erythematous flat-topped papules on the extensor surfaces of the elbows and knees, posterior cervical region and the dorsum of the hands (Figure 1). The findings were compatible with the diagnosis of frictional lichenoid dermatitis, no further studies were performed and the patient was treated with topical hydrocortisone during 2 weeks, with improvement.
Frictional lichenoid dermatitis is probably underdiagnosed and it is a benign and self-limited disease with typical clinical presentation, so it is important to recognize it as not to prescribe unnecessary workup and medication.
Key words: Dermatitis; Infant; Skin Diseases