梅毒による頬部瘻孔が疑われた例

抄録

Syphilis is a sexually transmitted disease caused by Treponema pallidum. Although the incidence of syphilis in Japan has decreased, cases of oropharyngeal syphilis are often reported. We report a case of fistula of the cheek probably due to syphilis. A 61-year-old woman noticed purulent discharge from the submandibular skin 3 months before the first visit. She also noticed purulent discharge from the right side of the neck. She visited a nearby hospital owing to a tumor that developed on her face, and was referred to us for further examination. A fistula was observed on the skin of the left cheek that contained granulation tissue with pus. Cutaneous indurations were observed in the left parotid and right supraclavicular regions. Computed tomography imaging of the neck demonstrated multiple lymph nodes with ring enhancement. The results of serological tests including quantitative serologic tests for syphilis and fluorescent treponemal antibody absorption were both positive. The histopathological features of the granulation tissue obtained from the cheek were compatible with those observed in syphilis, although spirochetes were not detected. The proliferation of blood vessels was prominent, and the growth of endothelial cells caused the obstruction of blood vessels. Infiltration of inflammatory cells including multinucleated giant cells was also observed. After treatment with oral amoxicillin over a period of 6 months, the fistula closed, and serological test results for syphilis improved.