PITYRIASIS RUBRA PILARIS : REPORT OF 16 CASES IN SAUDI ARABIA

Background: Pityriasis rubra pilaris (PRP) is a rare chronic papulosquamous disorder. There are a few world-wide large scale studies; and no reports of this dermatosis from Saudi Arabia. Objective: The present study was designed to highlight the main clinical and histological features of PRP as seen in a tertiary health care institution amongst Saudi patients. Methods: The diagnosis of PRP was made based on clinico-pathological correlation. The therapeutic response and disease course were evaluated by follow up appointments and re-examination of patients. Results: A total of 28 patients were reviewed, and the histopathological confirmation of the clinical diagnosis of PRP was in 16 patients. Griffith type I PRP was found in 12.5 %, type II PRP in 18.75%, type III in 18.75 % and type IV in 50 %. Type V was not observed in this case study. The cardinal clinical feature in this series was palmoplantar keratoderma which occurred in all 16 patients. In patients with types II PRP and IV PRP, lesions other than those located on the elbows and knees and palmoplantar keratoderma were common. Treatment with systemic Vitamin A, combination of Vitamin A and E, etretinate, acitretin and 13-cis-retinoic acid showed favorable variable response initially, however relapse occurred upon discontinuation of the treatment regimens. All the clinical types of PRP in this study showed a protracted course of more than 3 years duration. Limitations: This study is a retrospective study with high default rates. Conclusion: Type IV was the predominant type of PRP amongst Saudi patients. The diagnosis of PRP should be considered especially when patients present with acute onset keratoderma.