Neurosyphilis Presenting with Myelitis: A Case Report

Case Diagnosis: Syphilitic myelitis in an HIV-positive patient presenting with lower extremity weakness

Case Description or Program Description: We describe a case of a 35-year-old HIV-positive male presented with bilateral lower extremity weakness following a fall on a cruise ship. Since then, weakness progressively worsened associated with bowel and bladder incontinence over 6 weeks. He had also suffered from bilateral leg spasms. He was non-compliant to HIV medications for 5 years. However, he denied any balance problems or weaknesses prior to the event.

Setting: Inpatient rehabilitation hospital

Assessment/Results: Neurological examination revealed lower extremity weakness, more pronounced on the left than on the right. Tendon reflexes, sensation, and muscle tone were initially normal. T2-weighted MRI of the spinal cord revealed high signal intensity centered at T3 and extending to T2 and T4 with edema. A lumbar puncture was performed and CSF showed pleocytosis and elevated protein level. He had a reactive RPR of 1: 6. CSF VDRL was positive at 1:4 with elevated CSF IgG. The plasma CD4+ count was 19.7 and the HIV viral load was 2310. He received intravenous penicillin and steroids.

Discussion (relevance): Neurosyphilis involving the spinal cord mainly includes tabes dorsalis and syphilitic myelitis. It is more commonly seen in patients infected with HIV and low CD4+ counts. The main clinical presentations of syphilitic myelitis are acute or sub-acute onset of lower extremity weakness, sensory disturbance, and bladder or bowel dysfunction. The diagnosis is confirmed by a CSF WBC of 20 cells/microliter or greater, and/or a positive CSF VDRL test result, and/or a positive CSF intrathecal Treponema pallidum antibody index. The preferred treatment regimen is intravenous aqueous crystalline penicillin G of 2-4 million units every 4 hours for 10-14 days.

Conclusions: Syphilitic myelitis is an unusual presentation of neurosyphilis. We should consider the possibility, especially for HIV-co-infected patients.