[Cutaneous polyarteritis nodosa with manifestations of livedoid vasculopathy].

In a young woman, the differential diagnosis of ulcerated skin lesions on the lower limbs that heal leaving atrophic scars should include vasculitis and occlusive vasculopathy. Cutaneous polyarteritis nodosa (CPN) is characterized by the presence of painful nodules that typically develop on the lower limbs, frequently ulcerate, and usually heal without residual hyperpigmentation. Its diagnosis requires demonstration of necrotizing arteritis affecting mediumsized arteries. Livedoid vasculopathy (LV) is an occlusive vasculopathy with painful lesions in the form of punched-out ulcers that heal leaving white atrophic scars with peripheral telangiectasia. Light microscopy shows a mild superficial perivascular infiltrate and extravasation of red blood cells without vasculitis, although some arteries may present hyalinization of the wall and intraluminal fibrin deposits. We present a case in which the lesions showed the clinical and histological features of both disorders. The patient was 29-year-old woman with no past medical history of interest, who had been receiving aspirin 100mg/24 h and pentoxifylline 400mg/12 h for the last 8 years due to a skin disorder identified in another hospital as livedo reticularis. She was seen in our department for a 4-year history of outbreaks on the lower limbs of painful isolated lesions, sometimes ulcerated with serosanguineous crusts, and that disappeared after several months, occasionally leaving residual hyperpigmentation. The outbreaks appeared at random intervals and with no seasonal relationship. She had been treated with betamethasone plus gentamicin ointment, which, according to the patient, accelerated remission. She did not present Raynaud’s phenomenon or other systemic symptoms. There were 3 relevant findings on physical examination: a) hypopigmented stellate macules on the ankle, dorsal surface of the foot, and left pretibial region (Fig. 1A); b) an indurated erythematous red-brown plaque on the medial aspect of the left ankle with several well-defined ulcerated lesions (the largest being 0.8 cm in diameter) within its borders (Fig. 1B); and c) very faint reticulated violaceous macules on the upper and lower limbs. Skin biopsy from the area of the right lateral malleolus showed a necrotizing vasculitis affecting medium-sized vessels, with superficial changes consisting of vascular congestion with extravasation of red blood cells and, in some vessels, thrombosis and hyalinosis of the wall (Fig. 2). Blood analysis showed that antinuclear antibodies were negative (titer of 1:40) and cytoplasmic antineutrophil cyto-