In transverse myelitis (TM) disease, varying degrees of muscle weakness, sensory and autonomic disorders are seen in the individual due to the inflammatory process developing in the spinal cord. Inflammation involves a specific area of the spinal cord and damages the myelin layer, which provides the electrical insulation of the nerve fibers. Infections or when the immune system mistakenly attacks the body’s own tissue (autoimmunity) can cause transverse myelitis. Medications and physical therapy are used in the treatment.
Signs and Symptoms
While the spinal cord transmits the motor (movement) signals produced in the brain to the arms, trunk and legs, it also carries the sensory signals formed in these areas to the brain. Spinal cord inflammation disrupts the transmission of these signals, causing signs and symptoms. In transverse myelitis, weakness or paralysis often occurs in the legs in a relatively short time; The arms may also be affected to varying degrees. Involvement of the arms depends on the level of the disease in the spinal cord. Below the level of involvement, the light touch sensation is often impaired. Pain, temperature sensation, vibration sensation and position sense are also frequently affected senses. Hypersensitivity to touch may occur in a belt-shaped area on the trunk.
In relation to spinal cord damage in transverse myelitis, a sensory level located in the back region in adult patients and more often in the neck region in pediatric patients can be determined. Back, abdomen, arm, leg pain and numbness, tingling or burning sensations (paresthesia) are common. Bladder, bowel functions and sexual dysfunction may be seen. Complaints such as feeling of urgency or incontinence, difficulty urinating, incontinence or inability to make ablution may occur. Uncontrolled muscle spasticity and fatigue are other common symptoms. Depression can also be seen in these patients.
Symptoms settle within a few hours or days. In 80% of the patients, the disease takes its most severe form 10 days after the onset of the first complaints. On average, worsening occurs in the first 4-21 days. At their worst, half of the patients are unable to move their legs, around 80-94% have signs of paresthesia such as numbness, and nearly all have some degree of bladder dysfunction.
Healing can be complete or partial, and some people may not recover. In general, recovery begins within 1-3 months after acute treatment. If there is no improvement in the third month, the probability of significant improvement decreases. About one-third of patients recover completely or almost completely after the first attack. Moderate permanent functional limitation may occur in one third. In the remaining one-third, improvement may not be seen. Rapid progression of clinical symptoms, low back pain, presence of spinal shock, absence of central motor conduction response in evoked potential test and presence of 14-3-3 protein in cerebrospinal fluid (CSF) are negative indicators for complete recovery.
Although it is mostly a single attack, transverse myelitis may progress with recurrent attacks in a group of patients. Multifocal lesions in the spinal cord, lesions in the brain, underlying mixed connective tissue disease, oligoclonal bands in the cerebrospinal fluid, and/or NMO-IgG antibodies are risk factors for recurrence.
Why Does It Happen?
Transverse myelitis may develop alone or in the presence of another disease. Solitary idiopathic disease develops because the immune system is abnormally activated against the spinal cord and causes damage.
Transverse myelitis may occur as the first sign of multiple sclerosis. It has been reported that 10-33% of patients who develop acute partial TM and whose brain MRIs are normal develop MS within 5-10 years. In patients with lesions in brain MRI, the transition to MS occurs at a rate of up to 90% within a few years. Symptoms tend to be asymmetrical in people who are ultimately diagnosed with MS, sensory complaints are predominant while movement is relatively preserved. The rate of shifting the diagnosis to MS increases in patients with MR lesions that extend less than 2 spinal cord segments, those with abnormal brain MRI findings, and those with oligoclonal bands in the CSF.
TM may develop on the background of viral or bacterial infections. Measles, chicken pox, rubella, influenza, mumps are infections with known relationships in this respect. Damage to the spinal cord can occur as a direct result of the infection or due to the effect of the immune system response triggered by the infection. A bacterial abscess near the spinal cord can also injure the spinal cord with the compression effect and inflammation it causes.
Although a causal relationship has not been established, cases of TM after hepatitis B and flu vaccines have also been reported. These cases may be coincidence or an extremely rare complication of vaccination. It should be kept in mind that vaccines are generally quite safe and the benefits far outweigh the potential risks.
Rarely, cancer-related myelitis cases have also been observed.
It is estimated that between 1 and 8 new cases of transverse myalitis occur per million people each year. It can occur at any age, from infancy to advanced age. It is more common at the ages of 10-19 and 30-39 compared to other periods of life. A quarter of all cases occur in childhood. 75-90% of the time there is a single attack.
Transverse myelitis may develop in the background of rheumatological diseases such as systemic lupus erythematosus, Sjögren’s syndrome and sarcoidosis.
Diagnosis is made according to clinical and radiological findings. MR imaging is performed because of muscle strength, sensory and autonomic dysfunctions that indicate spinal cord injury. Inflammation may be demonstrated on MRI with gadolinium contrast. An increase in white blood cell count and IgG index or oligoclonal IgG bands may be observed in CSF analysis. The absence of inflammatory markers in the CSF analysis does not exclude the diagnosis of TM.
MR imaging is necessary to exclude causes such as hernia and tumor that compress the spinal cord. Another problem that can give similar findings to transverse myelitis is occlusion or circulatory disorder in the blood vessels feeding the spinal cord. Brain MRI enables the differentiation of diseases that can also affect the brain, such as MS.
IV (intravenous) steroid therapy is the first approach in acute transverse myelitis. Corticosteroids act by suppressing the inflammatory response of the immune system. If sufficient effect is not seen with iv steroid therapy for 5-7 days, plasma exchange therapy can be performed. In severe cases, plasma exchange can also be combined with steroids as first-line therapy. Plasma exchange is based on the logic of removing antibodies and other factors that may be related to autoimmunity in the blood. If sufficient results cannot be obtained with this method, iv pulse cyclophosphamide can be applied to suppress the immune system. The patient is followed closely during this treatment, which also has a risk of serious side effects. Long-term immunomodulatory therapy may be required in recurrent TM cases.
After the drug treatments in the acute period, the rehabilitation period begins. In rehabilitation, treatments for functional limitations caused by spinal cord damage are applied. Maintaining the range of motion of the joint, strengthening the muscles, managing spasticity, regulating bladder and bowel functions, detecting and managing psychological problems are the main issues in this process. Walking and balance exercises, robotic rehabilitation, occupational therapy are helpful. In the chronic phase, neuropathic pain associated with nerve damage may persist. For this, drug treatments from the antidepressant or antiepileptic group may be recommended. If there are problems related to spasticity, it can be beneficial with methods such as exercise, orthosis use, drug therapy and botulinum toxin A injections.