Cutaneous vasculitis, connective tissue diseases, and urticaria

Vasculitis (angiitis) denotes necrotizing inflammation of the blood vessels; occlusive vasculopathy implies vascular occlusion without significant vascular inflammation. A small-vessel cutaneous vasculitis is the most common vasculitis affecting the skin, and may be the first sign of a systemic vasculitis, but 50% of patients have no systemic disease. Systemic lupus erythematosus is diagnosed if four or more of the American College of Rheumatology revised criteria for the classification of this disease are present, either sequentially or simultaneously. Meanwhile, dermatomyositis is an uncommon multisystem autoimmune disease in which inflammatory skin changes are associated with polymyositis of skeletal muscle. Scleroderma means thickened, fibrotic, bound-down skin. It might develop in association with a systemic connective tissue disease (systemic sclerosis) or present as a localized cutaneous problem. Panniculitis is inflammation of the subcutaneous fat, sometimes associated with vasculitis. It presents with erythematous subcutaneous nodules, most often on the lower leg.