Background: Cutaneous periarteritis nodosa (PAN) is distinguished from systemic PAN by the lack of visceral involvement. The aim of this study was to describe the clinical presentation, laboratory findings, clinical course, and treatment in cutaneous PAN.
Patients and methods: We retrospectively reviewed the files of patients hospitalized for vasculitis in our Dermatology unit where approximately 20 cases of vasculitis are seen each year. Inclusion criteria were skin signs suggestive of PAN and a histological image of leukocytoclastic vasculitis of an arteriole.
Results: Nine cases of cutaneous PAN were treated in our unit between 1976 and 1997. Follow-up ranged from 32 months to 22 years. No cases of systemic PAN had been diagnosed during this period. These 9 cases of cutaneous PAN all had the same clinical presentation: nodules on the lower limbs in all cases associated with nodules on the upper limbs in half of the cases. Neuropathy was found in 3 of the 9 cases. No systemic involvement was observed. The most frequently used treatment protocol was general corticosteroid therapy (0.5 mg/kg/d prednisone or prednisolone). Immunosuppressive drugs, colchicine, dapsone, non-steroidal anti-inflammatory drugs and intravenous immunoglobulins were also used with efficacy.
Discussion: Cutaneous PAN is a particular form of vasculitis associating skin signs with locoregional neuromuscular involvement. The differential diagnosis with other types of vasculitis is sometimes a difficult task. The clinical course is the fundamental diagnostic clue in cutaneous PAN. A benign course and the absence of visceral involvement allow initiating a symptomatic treatment such as colchicine. The development of neuromuscular signs may warrant the use of general corticosteroid therapy.