Condition	Characteristics	Causes/associated findings
Eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome)	Palpable purpura, nodules, and ulcers on the lower extremities	Asthma, allergic rhinitis, eosinophilic pulmonary infiltrates, peripheral eosinophilia
Erythema multiforme	Symmetric target lesions on the hands and feet that are 1 to 3 cm in diameter; mucosal involvement is common	Herpes simplex virus, Mycoplasma pneumoniae, or upper respiratory tract infection
Erythema nodosum	Confined to extensor surfaces of the upper and lower extremities; erythematous, tender nodules that are 1 to 10 cm in diameter	Beta-hemolytic streptococcal infection, other bacterial and fungal infections, pregnancy, medication use, systemic illness
Leukocytoclastic (hypersensitivity) vasculitis	Palpable purpura on the lower extremities; may be pruritic and painful	Infection, connective tissue disorder, medication use