Syphilitic myelopathy (tabes dorsalis)

Overview

Alternative Names: Tabes dorsalis. Syphilitic myelopathy is a complication of untreated syphilis that involves muscle weakness and abnormal sensations.

Symptoms

* Abnormal sensations, often called "lightning pains" * Difficulty walking * Loss of coordination * Loss of reflexes * Muscle weakness * Wide-based gait (the person walks with the legs far apart)

Causes

Syphilitic myelopathy is a form of neurosyphilis, which is a complication of late or tertiary syphilis infection. Syphilis is a sexually transmitted, infectious disease. For information on the disease, see: Syphilis. The condition called tabes dorsalis includes syphilitic myelopathy and additional symptoms of nerve damage. The infection damages the tissue of the spinal cord and peripheral nervous tissue. This causes decreased muscle function (myelopathy), including progressive weakness of the legs, arms, and other areas. Loss of function may eventually result in paralysis. Coordination difficulties contribute to problems walking. There are often changes in sensation, including painful paresthesia (abnormal sensations), which are also referred to as "lightning pains." In syphilitic myelopathy, the muscle problems are accompanied by other symptoms characteristic of nervous system damage caused by syphilis. These include vision changes, stroke, and psychiatric illness. Syphilitic myelopathy is now very rare because syphilis is usually treated early in the disease or as a result of screening blood tests that identify the disease in its latent (silent) form. Such blood tests are performed, for example, on individuals who donate blood and during pregnancy.

Prevention

Adequate treatment and follow-up of primary syphilis infections reduces the risk of developing syphilitic myelopathy. If you are sexually active, practice safe sex and always use a condom. All pregnant women should be screen for syphilis.

Diagnosis

Physical examination may suggest myelopathy. Decreased or absent reflexes may be present due to nerve damage. Tests may include the following: * Head CT, spine CT, or MRI scans of the brain and spinal cord to rule out other diseases * Serum VDRL or serum RPR (used as a screening test for syphilis infection -- if positive, one of the following will be required to confirm the diagnosis): - FTA-ABS - MHA-TP * CSF (cerebrospinal fluid) examination - abnormal results indicating chronic meningitis - a positive neurosyphilis test (CSF VDRL test)

Prognosis

Progressive disability is possible if the disorder is left untreated.

Treatment

The goals of treatment are to cure the infection and to reduce progression of the disorder. Treatment of the infection reduces new nerve damage and may reduce symptoms but does not cure existing nerve damage. For neurosyphilis, aqueous penicillin G (by injection) is the drug of choice. Some patients with penicillin allergies may undergo desensitization to penicillin so that they can be safely treated with it. Treatment of symptoms is required for existing neurologic damage. Assistance or supervision may be needed if the person is unable to perform self-care activities (eating, dressing, etc.). Rehabilitation, physical therapy, occupational therapy, or other interventions may be appropriate for people with muscle weakness. Analgesics may be required to control pain. These may include over-the-counter medications such as aspirin (oral salicylates) or acetaminophen for mild pain but narcotics may be required. Anti-epilepsy drugs such as carbamazepine may have a role in the treatment of lightning pains.

Resources

Call your health care provider if loss of coordination, loss of muscle strength, or loss of sensation occurs.