A febrile illness with raised painful plaques on the limbs, face, and neck; neutrophilic leukocytosis; and dense neutrophilic infiltrates in the skin lesions. It responds promptly to treatment with glucocorticoids. Although the cause is unknown, the condition is often associated with the administration of drugs (such as hydralazine or sulfa drugs) and occasionally is found in persons with connective tissue diseases, hematological malignancies, or inflammatory bowel disease.