Cutaneous polyarteritis nodosa: A rare isolated cutaneous vasculitis.

Cutaneous polyarteritis nodosa (CPAN) is a rare form of cutaneous vasculitis that involves small and medium sized arteries of the dermis and subcutaneous tissue without systemic involvement. It presents with tender subcutaneous nodules, digital gangrene, livedo reticularis and subcutaneous ulcerations. The diagnosis is by skin biopsy and characteristic pathologic feature is a leukocytoclastic vasculitis in the small to medium-sized arterioles of the dermis.