The Syphilis Comeback: Dental Perspective on the “Great Imitator”

By Dr Amanda Phoon Nguyen Dec 24

Dental professionals should be aware of the oral manifestations of syphilis to ensure early detection and prompt treatment, especially since oral lesions may be the first manifestation of the disease.  Unfortunately, lack of awareness and wide variability in presentation of oral lesions (hence the nickname “the Great Imitator”) syphilis is often not considered as a potential diagnosis. Despite the availability of effective therapies, resurgence of syphilis in recent years and ongoing outbreaks in Australia, highlights the importance of dental professionals understanding the disease, its various stages, and recognising oral manifestations. 

What is syphilis?

Syphilis is a systemic infectious disease caused by the filamentous, anaerobic spirochaete Treponema pallidum. The disease can be transmitted sexually (acquired syphilis) or vertically via the placenta (congenital syphilis). In addition, direct contact with an infected patient’s lesions, blood, or saliva can also serve as a vector for syphilis transmission. 

There are three main stages of the disease each with different clinical presentations and infectivity. Oral lesions may occur at any of the three stages and these manifestations of syphilis are highly variable often leading to delayed detection in secondary stage.

If syphilis is not treated, it can lead to severe consequences for the infected individual, such as long-term neurological and cardiac complications as well as public health concerns regarding spread within the population. Risks during pregnancy including stillbirth and congenital syphilis.

Primary syphilis manifests with an infectious, painless, indurated ulcer known as a chancre, typically appearing 1 to 3 weeks post-inoculation. Chancres may resolve without treatment, but this does not mean syphilis has been cured, hence resolution of a suspected syphilitic chancre should not deter prompt referral. Orogenital or oroanal contact with an infectious lesion at this early stage of the disease is a common mode of transmission. Kissing may, rarely, cause transmission.   Considering syphilis as a potential diagnosis for oral ulceration is essential for recognizing and diagnosing primary syphilis accurately.

Secondary syphilis is characterised by haematogenous spread of T. pallidum, leading to more diverse and extensive systemic and oral manifestations compared with the primary stage. Mucous patches, maculopapular and nodular lesions are among the potential features seen during this phase.

Tertiary syphilis occurs as a consequence of untreated secondary syphilis, often marked by complications such as gumma formation. These are ulcerative, nodular lesions that tend to arise on the hard palate and tongue, tonsils or lips. Gummas carry significant implications such as bony destruction, and timely intervention is necessary to prevent further disease progression. The complications of tertiary syphilis centre upon gumma formation, and rarely, syphilitic leucoplakia and neurosyphilis.

In summary, dental professionals are well-placed to detect oral manifestations of syphilis, ensure appropriate management and prompt referral. If you suspect your patient has an oral lesion due to a syphilis infection, the patient should be referred promptly to the patient’s GP/primary health care provider or a sexual health service for diagnosis, notification and treatment.