Oral Manifestations of Syphilis: a Review of the Clinical and Histopathologic Characteristics of a Reemerging Entity with Report of 19 New Cases.

Background Syphilis is a sexually-transmitted infectious disease caused by Treponema pallidum. Cases of primary and secondary syphilis are on the rise in the United States, with a 14.4% increase in new cases noted from 2017 to 2018 and an escalation of 71% between the years 2014 and 2018. Fulfilling its nickname of "the great imitator," oral manifestations of syphilis may mimic a variety of infectious, neoplastic, or immune-mediated processes, both clinically and histopathologically. This large spectrum of appearances can create a diagnostic challenge to the clinician and/or pathologist, leading to delay in diagnosis or misdiagnosis. Methods A database of oral syphilis cases was created from archives at the University of Kentucky, University of Pittsburgh, LIJMC, Columbia University MC, and University of Tennessee. The age, sex, race, location, duration, and clinical description were recorded. Cases without positive reaction upon immunohistochemistry or serologic tests were excluded. Results We identified 19 new cases of oral syphilis (17 males, one female, and one case unknown sex) and described the clinical and histopathological features of this re-emerging and potentially fatal disease. All cases demonstrated dense lymphoplasmacytic inflammation, often with inflammatory exocytosis or ulceration at the surface, and perivascular inflammation. Conclusions Early recognition of the histopathologic and clinical manifestations of oral syphilis is imperative for prompt diagnosis, improved patient outcomes, and disease prevention.