Histological examination of the skin biopsy specimen obtained from the edge of an ulcer revealed mild acanthosis, spongiosis, and exocytosis of lymphocytes and neutrophils. Focal necrosis and microabscess formation were evident. There was a perivascular and periappendageal neutrophilic infiltrate. A dense, diffuse infiltrate of neutrophils and mononuclear cells extended from the papillary dermis into the reticular dermis and superficial fat. Special stains were negative for fungi and bacteria. The patient began high-dose oral corticosteroid therapy, with improvement of her pain and skin lesions.
Skin Ulcers Associated With a Tender and Swollen Arm. Arch Dermatol. 1998;134(9):1145-1150. doi: