Juvenile pityriasis rubra pilaris: Report of 28 cases in Taiwan

Background: Pityriasis rubra pilaris (PRP) is a papulosquamous dermatosis uncommon in juveniles. Large-scale studies are limited, especially from Asian countries. Objective: We sought to analyze the clinical manifestations of juvenile PRP in Taiwanese patients and compare them with reported series in the literature. Methods: The diagnosis of juvenile PRP was made based on clinical-histopathologic correlation. The therapeutic response and disease course were followed up by re-examination of the patients or by telephone. Results: A total of 47 patients were identified, with histopathologic confirmation of the clinical diagnosis of juvenile PRP in 28 cases. A preponderance of Griffiths' type IV PRP (85.7%) rather than type III PRP (14.3%) was found. Palmoplantar hyperkeratosis appeared to be a cardinal feature. In patients with type IV PRP, skin lesions in areas other than the elbows/knees and palms/soles were common. Treatment with systemic acitretin in 6 patients failed to effect a dose- or time-dependent improvement. In contrast with other studies, two thirds of our patients with type III and IV juvenile PRP had a protracted course lasting more than 3 years. Limitations: This study was a retrospective review. Patient compliance with treatment was frequently poor. Conclusions: Type IV juvenile PRP predominated but our cases showed a wider distribution of skin lesions than is typically described. When children present with an acute onset of diffuse palmoplantar hyperkeratosis, a diagnosis of juvenile PRP should be considered. Because of the divergent clinical manifestations of juvenile PRP in different populations, there is a need to modify and re-evaluate classification systems based on regional differences.