Definition

Tabes dorsalis is a complication of untreated syphilis that involves muscle weakness and abnormal sensations.

Alternative Names

Locomotor ataxia; Syphilitic myelopathy; Syphilitic myeloneuropathy; Myelopathy - syphilitic; Tabetic neurosyphilis

Causes

Tabes dorsalis is a form of neurosyphilis, which is a complication of late stage syphilis infection. Syphilis is a bacterial infection that is spread sexually.

When syphilis is untreated, the bacteria may damage the spinal cord and peripheral nervous tissue. This leads to the symptoms of tabes dorsalis.

Tabes dorsalis is now very rare because syphilis is usually treated early in the disease.

Symptoms

Symptoms of tabes dorsalis are caused by damage to the nervous system. Symptoms include any of the following:

• Abnormal sensations (paresthesia), often called "lightning pains"
• Problems walking due to nerve damage causing the person to walk with the legs far apart and feet slapping the ground
• Loss of coordination and reflexes
• Joint damage, especially of the knees
• Muscle weakness
• Vision changes
• Bladder control problems
• Sexual function problems

Exams and Tests

The health care provider will perform a physical exam, focusing on the nervous system.

If syphilis infection is suspected, tests may include the following:

• Cerebrospinal fluid (CSF) examination
• 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 the serum VDRL or serum RPR test is positive, more tests are done to confirm the diagnosis.

Treatment

The goals of treatment are to cure the infection and slow the disease. Treating the infection helps prevent new nerve damage and may reduce symptoms. Treatment does not reverse existing nerve damage.

Medicines likely to be given include:

• Penicillin or other antibiotics for a long time to make sure the infection goes away
• Painkillers to control pain

Symptoms of existing nervous system damage need to be treated. People who are unable to eat, dress themselves, or take care of themselves may need help. Rehabilitation, physical therapy, and occupational therapy may help with muscle weakness.

Outlook (Prognosis)

Left untreated, tabes dorsalis may lead to disability.

Possible Complications

Complications may include:

• Blindness
• Paralysis

When to Contact a Medical Professional

Contact your provider if you have:

• Loss of coordination
• Loss of muscle strength
• Loss of sensation

Prevention

Proper treatment and follow-up of syphilis infections reduces the risk of developing tabes dorsalis.

If you are sexually active, practice safer sex and always use a condom.

All pregnant women should be screened for syphilis.

References

Ghanem KG, Hook EW. Syphilis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 303.

Radolf JD, Tramont EC, Salazar JC. Syphilis (Treponema pallidum). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 237.