Suppurative cribriform ulcers in one leg

An 89‐year‐old female presented with a 3‐year history of painless ulcers on right lower leg. Each lesion began as small nodules that gradually ulcerated and expanded (Figs. 1 and 2). She had similar ulcers on the same leg, which spontaneously healed over months in the past year. There was no preceding trauma or environmental water exposure. She denied fevers or systemic symptoms. Her past medical history is significant for ischemic heart disease, coronary arterial bypass, stroke, hypertension, and right lower limb venous insufficiency. Clinical examination revealed multiple superficial ulcers with an exudative base and surrounding erythema, distributed over her right distal leg from the mid shin to ankle with several erythematous nodules adjacent to the right knee. Angiotensin converting enzyme (ACE) levels, rheumatoid factor, and antineutrophil cytoplasmic antibodies were not raised. There was no hilar lymphadenopathy on chest radiography. Bone scan and Doppler ultrasonography excluded osteomyelitis and arterial disease, respectively. She reported no improvement after receiving multiple courses of antibiotic therapy. We performed multiple skin biopsies for histopathology and tissue culture (Figs. 3 and 4). Histopathology demonstrated a zone of dermal necrosis lined by granulomatous palisading epithelioid histiocytes with multinucleated giant cells undermining an acanthotic epidermis. The granulomatous reaction was associated with an inflammatory infiltrate of lymphocytes, neutrophils, and plasma cells. Special stains for organisms, including mycobacterial and fungi, were negative. Tissue cultures sent for atypical mycobacteria and fungi, as well as panmycobaterium DNA polymerase chain reaction, were negative on two separate occasions.