Syphilis is classified into three stages: primary, secondary, and tertiary. While these stages usually occur in sequence, they may overlap, as seen in our patient. The lesion of primary syphilis is described as a painless papule that emerges at the site of inoculation approximately 2 to 3 weeks after infection and later ulcerates to form a chancre . While primary syphilis typically involves genitalia, oral manifestations are observed in approximately 4–12% of patients, reflecting sexual practices . These lesions are often described as painless indurated ulcers commonly involving the tongue, gingiva, soft palate, and lips that typically last between 3 and 7 weeks . Our patient presented with an ulcerated chancre on his hard palate, probably secondary to engagement in oral-genital sex with his partner. Other risk factors associated with the development of oral lesions include oral-anal sex and kissing . Primary chancres on the hard palate are very rare and have only been reported in a few cases previously [3,4,5].
As the chancre develops, treponemes disseminate widely throughout the body. Disseminated lesions indicate progression to the second stage of infection and appear 4 to 10 weeks after the chancre is first seen, when a painless macular rash erupts over the trunk and extremities that extends to the palms and soles in a manner similar to our patient’s presentation (Fig. 1). As demonstrated by our case, many patients with secondary syphilis present with nonspecific symptoms such as fever, sore throat, weight loss, and lymphadenopathy . Oral manifestations can also be seen during this stage and typically involve the soft palate and pillars, tongue, and vestibular mucosa . Although oral manifestations of syphilis are relatively common, the lips serve as the most common site of oral lesions whereas lesions of the hard palate or labial commissure are very rarely reported and have previously occurred in the setting of multiple lesions [4, 6]. This case report is one of only a few reports of a primary syphilitic chancre on the hard palate of the oral cavity (Fig. 2), and our patient’s diffuse macular rash further indicated an overlapping progression to the second stage of infection (Fig. 1).
Our patient also presented with prominent submental lymphadenopathy characteristic of the regional lymphadenopathy seen in syphilitic disease. In approximately 80% of cases, syphilitic chancres are accompanied by painless regional lymphadenopathy, typically occurring 7 to 10 days after the appearance of the chancre . While syphilis involving the genital region causes inguinal lymphadenopathy, lymphadenopathy can involve the cervical region in patients with oral syphilitic disease, as demonstrated by this case. In Chapel’s study of 105 patients with secondary syphilis, lymphadenopathy was present in the inguinal region of 79 patients, axillae of 40 patients, posterior cervical triangles of 29 patients, anterior cervical triangles of 24 patients, epitrochlear region of 18 patients, femoral region of 19 patients, and supraclavicular areas of 4 patients . Characteristic pathology involves granulomas with epithelioid histiocytes, few multinucleated giant cells, and occasional necrosis, as seen in our patient .