Familial pityriasis rubra pilaris: report of a family and therapeutic response to etanercept.

Pityriasis rubra pilaris (PRP) is an uncommon dermatosis of unknown etiology. The familial subtype is rare and usually presents as type V PRP. It is generally inherited in an autosomal dominant fashion with variable expression. Other forms of inheritance, such as autosomal recessive and X-linked, have also been reported. The use of etanercept in treating resistant forms of PRP is promising given reports of its success in a few cases. Herein, the authors report two cases of PRP arising in a mother and son and review the rare familial subtype of this disease. In addition, a successful therapeutic trial of etanercept was initiated in the mother based on case reports of its efficacy in other patients with PRP.