Introduction. pityriasis rubra pilaris (PRP) is a heterogeneous group of disorders that have in common follicular keratotic papules, branny scales and erythema. Five types of PRP can be distinguished. Types I and II occur in adults (classical disseminated and atypical form), while types III-V represent juvenile forms of PRP (classical, circumscribed and atypical). In type IV juvenile PRP keratotic circumscribed plaques are located mainly on elbows, knees and ankles.

Objective. To present the case of a 15-year-old boy with juvenile type IV, limited pityriasis rubra pilaris, to facilitate recognition of such cases.

Case report. The 15-year-old boy has had for five years well-circumscribed erythematous plaques with follicular keratotic papules and pityriasiform scaling located on elbows, knees and ankles. He has been diagnosed with psoriasis. The clinical and histopathological findings were consistent with a diagnosis of type IV pityriasis rubra pilaris. We began the treatment with emollients and adapalene. The boy was under observation.

Conclusions. pityriasis rubra pilaris like lesions on elbows and knees should be differentiated with psoriasis.