Osler Nodes vs. Janeway Lesions
The differences between these two cutaneous presentations of Infectious endocarditis have always been a bit tricky for me. Finally I decided to solve that problem and here it is:
Osler nodes: Osler’s nodes (painful, palpable, erythematous lesions most often involving the pads of the fingers and toes). Caused by immune complexes (they want you to know that for Step 2). Infectious endocarditis and Roth spots are also due to immune complexes–>immune vasculitis.
Janeway lesions (nontender, macular lesions most commonly involving the palms and soles). Janeway lesions occur more frequently in endocarditis caused by Staphylococcus aureus. Janeway lesions are caused by septic emboli. Subcutaneous abscesses are found on histologic examination.
We can add to the picture and splinter hemorrhages aka fingernail hemorrhage: narrow, red to reddish-brown lines of blood beneath the nails. They run in the direction of nail growth and are named splinter hemorrhages because they look like a splinter beneath the fingernail. The hemorrhages may be caused by tiny clots that damage the small capillaries under the nails or by vessel damage from swelling of the blood vessels (vasculitis). [medlineplus]
The most common cause for splinter hemorrhages is trauma to the nail. [umm]
PICTURE (Credit Children’s Hospital Boston): The lesions in Figures A-C were tender and represent Osler’s nodes, while the lesion in Figure D was nontender and represents a Janeway lesion.
For more pictures showing the differences between Osler Nodes and Janeway Lesions visit er119test.