Ulcer on knuckle
A 42-year-old woman presented with a 6-week history of painful, red and yellow-red, nonblanching papules on the dorsal hands. One of the papules over a proximal interphalangeal joint had ulcerated completely through to the joint capsule; it glistened white when the skin was rotated over it. The patient was otherwise healthy, and a review of systems was negative for gastrointestinal symptoms.
What’s your diagnosis?
Since the papules were worrisome for vasculitis, 2 punch biopsies were performed on smaller, younger lesions on the hand and 1 was submitted for direct immunofluorescence. Findings revealed a leukocytoclastic vasculitis (LCV) with prominent immunoglobulin A (IgA) deposits around the vessel wall. The clinical and pathologic findings were consistent with a rare fibrosing LCV called erythema elevatum diutinum (EED). The practice of sampling nonblanching purpura or papules for both standard pathology (hematoxylin and eosin) and direct immunofluorescence can facilitate the diagnosis of unusual conditions that may occur only a few times in one’s career.
EED is rare, chronic, and may be associated with IgA gammopathy, IgA antineutrophil cytoplasmic antibodies, recent streptococcal or HIV infections, or myelodysplastic syndrome. A robust work-up to identify whether any of these factors are at work is critical.1 Distinct from other vasculitides, EED forms granulation tissue that becomes reinjured.
This patient was found to have an IgA monoclonal gammopathy that was monitored by Hematology. After checking her glucose-6-phosphate dehydrogenase activity, she was treated with oral dapsone 25 mg/d. Dapsone was titrated up to 100 mg/d, which improved her symptoms considerably and the ulcerated papule was surgically revised and closed. EED can last for years and ultimately clear or can persist indefinitely.
Text courtesy of Jonathan Karnes, MD, medical director, MDFMR Dermatology Services, Augusta, ME. Photos courtesy of Jonathan Karnes, MD (copyright retained).