Syphilitic Meningomyelitis Mimicking Subacute Combined Degeneration of the Spinal Cord on Magnetic Resonance Imaging.

A 40-year-old man presented with a gait disturbance and sensory ataxia. He was not an HIV carrier or homosexual. About 20 years prior, he noted skin lesions usually seen in early-stage syphilis, but did not receive adequate treatment. Magnetic resonance imaging of the spinal cord demonstrated increased signal intensity within the dorsal column on T2-weighted images, with longitudinal extension from C2 to T10, and without gadolinium-enhancement. These findings mimicked sub-acute combined degeneration. He was diagnosed as having neurosyphilis, as the criteria for syphilitic meningomyelitis were met, and was treated with the intravenous penicillin G potassium (24-million IU/day for 14 days). The initial treatment failed to relieve his neurological symptoms and abnormal spinal cord findings were observed 6 months later, despite improvement in cerebrospinal fluid rapid plasma regain level and Treponema pallidum hemagglutination assay titers. Providing young and sexually active people with appropriate information is a crucial public health measure to prevent progression of syphilis when treatment is not performed during the asymptomatic phase between early and late symptomatic phases