The clinical features of syphilitic myelitis with longitudinally extensive myelopathy on spinal magnetic resonance imaging: a case report and literature review

Abstract Background: Syphilitic myelitis as a bacterial infection caused by Treponema pallidum, is a very rare manifestation of neurosyphilis. The magnetic resonance imaging (MRI) appearance of longitudinally extensive myelopathy with syphilitic myelitis is not well documented and only a few cases have been reported about its’ clinical features. Case presentation: Herein, we report a patient who suffered from syphilitic myelitis with symptoms of sensory disturbance, with longitudinally extensive myelopathy with "flip-flop sign" on spinal MRI. This patient performed complete clinical and radiologic recovery after treatment. We also summarized the clinical features of syphilitic myelitis with longitudinally extensive myelopathy from the reported literatures published in English language. A total of 16 articles of 20 cases between January 1987 and December 2018 were identified. Of the 20 patients with syphilitic myelitis, the age of onset varied between 17 and 63 years. Sixteen patients were males (80%). Sixteen patients presented with the onset of sensory disturbance (80%), 15 with paraparesis (75%), 9 with urinary retention (45%). Eleven patients had high risk behavior (55%). Five patients had concomitant HIV infection (25%). Serological data showed 15 patients performed with positive venereal disease research laboratory (VDRL)/ treponema pallidum particle agglutination (TPHA), and 17 patients with positive VDRL/TPHA in cerebrospinal fluid (CSF). Seventeen patients with elevated cells and protein in CSF. On MRI, 16 patients showed abnormal signal intensities involved thoracic spine, 6 involved cervical, and 3 involved both cervical and thoracic spine. There were 3 patients performed with the "flip-flop sign". All the patients were treated with penicillin, and 15 patients were performed with a better prognosis. Conclusions: Syphilitic myelitis is a relatively rare feature of Treponema pallidum infection. Early definite diagnosis and antibiotic therapy are crucial for minimizing neurological sequelae. Our case also raises awareness of syphilitic myelitis as an important complication of neurosyphilis due to homosexuality, especially in developing countries.