Unilateral palpable purpura. A manifestation of septic emboli from an infected aortofemoral bypass graft eroding the jejunum.

A 48-year-old man had a palpable purpuric eruption of the right lower extremity several years after a right aortofemoral bypass graft for obstructive atherosclerotic disease. Histologic examination revealed a leukocytoclastic angitis, and belated tissue Gram's stains disclosed clumps of Gram-negative organisms. The focus for the unilateral purpura proved to be an erosion of the jejunum by the bypass that yielded Enterobacter aerogenes on culture, as did one preoperative blood sample.