Extracorporeal photochemotherapy for the treatment of exanthematic pityriasis rubra pilaris

Summary Pityriasis rubra pilaris (PRP) is a rare papulosquamous skin disease of unknown aetiology that has been categorized into five clinical types based on age at onset, cutaneous features and prognosis. We present a patient with chronic exanthematic type II atypical adult PRP, whose skin status was significantly improved with monthly extracorporeal photochemotherapy (ECP). Various therapeutic regimens including narrow‐band UV‐B, bath PUVA therapy, systemic fumaric acid esters and systemic cyclosporin had failed. Oral retinoids could not be administered due to a type IIa hyperlipoproteinemia with profound hepatic steatosis and elevated liver transaminases. The observed clinical benefit may encourage future clinical studies analysing the effectiveness of ECP in otherwise unresponsive cases of type II PRP.