The histopathology of syphilis of the oral mucosa

Reported cases of syphilis in the United States, Europe and elsewhere are increasing in number. Clinical manifestations are protean, and oral biopsies may be taken where the diagnosis is unsuspected, but data on the histopathology of oral mucosal syphilis are sparse.

The histopathology of five oral lesions in patients with serologically proven syphilis was reviewed.

There were two cases of primary syphilis, one secondary and two tertiary. Epithelial hyperplasia was present in three cases, and was pseudocarcinomatous in one case of primary syphilis, and psoriasiform in the secondary lesion, where heaped-up epithelium surrounded a defined crater covered by flatter epithelium. Plasma cell (primary and secondary disease) and granulomatous (tertiary) infiltrates were prominent. Other features observed were endarteritis (5/5), plasma cell neuritis (3/5) and spirochetes (4/5).

Although no single microscopic feature is specific, a diagnosis of syphilis should be considered where there is unusual epithelial hyperplasia, granulomatous or plasma cell-predominant chronic inflammation, endarteritis and neuritis.