Annular leucocytoclastic vasculitis.

Leucocytoclastic vasculitis (LV) is characterized by necrotizing inflammation around small blood vessels, composed mainly of neutrophils and their debris. The skin lesions of LV are polymorphous, but an annular variant is rare. Four previous reports have named this variant 'annular LV' (ALV) and in this paper, we report two additional cases. Patient 1 was a 80-year-old man, who presented with pruritic, erythematous target lesions on his legs, soles, abdomen and axillae; histological examination showed typical LV throughout the entire dermis. Oral prednisolone 15 mg daily rapidly resolved the patient's symptoms. Patient 2 was a 64-year-old man, who was referred to our hospital because of multiple purpuric target lesions on the buttocks, right thigh, lower legs, upper arms and forearms. Histopathology revealed LV throughout the entire dermis. Oral prednisolone 20 mg daily rapidly resolved the lesions. We categorized these cases morphologically as ALV and clinically as small-vessel vasculitis. ALV is not a distinct condition, but includes a broad range of small-vessel vasculitides.