| Janeway lesion | |
|---|---|
 | |
| Specialty | |
| Symptoms | Painless red flat papules on palms and soles[1] |
| Usual onset | Sudden |
| Duration | Days to weeks[1] |
| Causes | Infective endocarditis[1] |
| Diagnostic method | Appearance[1] |
| Differential diagnosis | Osler's nodes[1] |
Janeway lesions are rare, non-tender, smallerythematous orhaemorrhagicmacular,papular ornodular lesions on the palms orsoles only a few millimeters in diameter that are associated withinfective endocarditis and often indistinguishable fromOsler's nodes.[1]
Janeway lesions are painless, frequently haemorrhagic lesions seen most commonly on the palms and soles, particularly on the base of the thumb and little finger, and seen in infective endocarditis.[2]
Osler's nodes and Janeway lesions are similar and point to the same diagnostic conclusion.[1] The most significant difference between the two is that Osler's nodes present with tenderness, while Janeway lesions do not.[1] Osler's nodes are thought to be due to immunologic phenomenon where deposition of immune complexes provoke inflammatory response, leading to swelling, redness and pain. On the contrary, Janeway lesions are thought to be due to embolic phenomenon in cutaneous blood vessels of palms and soles which does not cause pain or least pain.[3][4]
Pathologically, the lesion is described to be amicroabscess of thedermis with markednecrosis and inflammatory infiltrate not involving theepidermis.[5]
They are caused by septic emboli which deposit bacteria, forming microabscesses.[6] Organisms may be cultured from the lesions.[7]
Janeway lesions present as red, painless macules and papules on the palms and soles.[2]
They are not common and are frequently indistinguishable fromOsler's nodes. Rarely, they have been reported in cases ofsystemic lupus erythematosis (SLE),gonococcemia (disseminated gonorrhoea),haemolytic anaemia andtyphoid fever.[2]
They may last days to weeks before completely resolving.[1]
Janeway lesions are named afterEdward Janeway (1841–1911), a prominent American physician, pathologist and contemporary of SirWilliam Osler, who initially described "peculiar skin lesions" in some people with endocarditis, in a paper published in 1899. The term was first used byinternist and pathologistEmanuel Libman, who reported the lesions in his paper of 1906 and explained his reasoning for using the term "Janeway lesions" in a footnote in 1923. Osler never mentioned Janeway lesions. The inclusion into Osler's 1925 textbook came six years after Osler died.[8]