Janeway lesions and Osler's nodes: a review of histopathologic findings.

The histologic findings in Osler's nodes and Janeway lesions have been reported rarely; we found descriptions of only 10 such cases, mostly from the late nineteenth- and twentieth-century French literature. We found gram-positive coccobacilli in the dermal abscess of a Janeway lesion from a patient with bacterial endocarditis. This finding suggests that septic microemboli are the cause.