Syphilitic Gumma Lesion in Meckel’s Cave and Infratemporal Fossa Presenting with Cranial Nerve Deficit

We describe the case of a 54-year-old man presenting with symptoms of left otalgia with irradiation to the jaw. Initial investigation revealed an isointense T1, hypointense T2, and homogenously enhancing nodular lesion invading the left Meckel’s cave, spreading into rotundum and ovale foramina toward the infratemporal fossa. There was also infiltration of the pterygoid muscles. Biopsy was done through an endoscopic transmaxillary approach directed at this lesion in the pterygomaxillary and infratemporal fossa. The initial diagnosis was hemangioma.

On follow-up, the patient’s symptoms persisted and the lesion increased in size, extending in the temporal fossa. The patient was then referred to a skull base neurosurgeon for a second biopsy.

Because progression of hemangioma is not typical, complete extension workup was done to eliminate tumoral process or infectious pathology. On questioning, the patient mentioned subjective improvement of symptoms with antibiotics, and also that he had been treated for syphilis in 2010.

Further tests, including RPR, CSF VDRL, and Lyme serology, concluded for a positive infection with syphilis. The lesion was presumably a syphilitic gumma, compressing the auriculotemporal nerve, a branch of V2 but also the mandibular division (V3) of the trigeminal nerve. The lesion regressed after a few weeks of intravenous antibiotic treatment. The patient’s symptoms also improved on medical treatment and did not require surgical treatment.

This case is a reminder that although quite rare, tertiary syphilis can present as syphilitic gumma with cranial nerve deficit. Revision of risk factors and patient history can lead to appropriate treatment. Diagnosis can be difficult because MRI anomaly can be described with many lesions, including tumoral, inflammatory, and infectious diseases.