Transverse myelitis is an inflammation of the spinal cord. It is a neurological condition in which the inflammation of the spinal cord leads to damage of the nerve fibers causing them to lose their myelin sheath and decrease in their ability to conduct electricity within the nervous system.
Presentation
There are 4 classic features of transverse myelitis,
The presentation can either be acute when it develops within days or subacute when it develops within weeks. Symptoms include lower back pain, sudden paresthesia in the legs which may described by patient as burning, tingling, pricking, or tickling sensations. There is also sensory loss in the lower limbs and paraparesis (partial paralysis of the lower limbs) which may progress to paraplegia (total paralysis of the lower limbs). Sensory defect will also affect the autonomic nervous system causing symptoms like urinary and bowel incontinence. There will be history of muscle spasms, headache, fever, general feeling of unwell and discomfort, and loss of appetite. If the lesion is higher up the spinal cord, respiratory problems may be experienced [6].
Workup
- Radiological tests are important in diagnosis to rule out other causes of the experienced symptoms or an underlying cause of this condition. An MRI is done to examine structural damage to the brain or spinal cord, like spinal cord compression which could also produce similar symptoms [7]. The brain MRI may detecting underlying causes like multiple sclerosis. A contrast CT scan is done when an MRI is not available [8].
- Various blood tests are also done to rule out other underlying conditions like HIV, vitamin B12 deficiency, and systemic lupus erythematosus.
- A lumbar puncture will reveal increased white blood cells in case of an infection and can be used to look for disease markers.
- If no specific cause can be gotten from these tests, the patients is said to have idiopathic transverse myelitis [9].
Treatment
- The treatment for this condition is designed to manage symptoms and reduce spinal cord inflammation as there are no definitive treatments. Intravenous steroids are used soon after diagnosis to reduce inflammation and improve neurological recovery. Steroids that might be used are methylprednisolone and dexamethasone.
- Plasma exchange therapy is instituted in those with moderate to severe disease and in those who don’t respond to steroid therapy.
- Other immunomodulatory treatment like intravenous cyclophosphamide can be used in patients that do not respond to the above treatments.
- The most critical part of management involves maintaining the physiological functioning of the patient.
Prognosis
Recovery from this condition may begin from anytime between 2 to 12 weeks and lasts for up to 2 years. If there is no improvement within the 6 months, then complete recovery is unlikely. About one-third of patients experience full recovery, the other one-third experience partial recovery while the last one-third experience no recovery at all, and will depend on others for basic daily functions. Aggressive treatment and physical therapy will help improve outcomes. Research has shown that if symptoms start rapidly, prognosis will most likely be bad [5].
Etiology
There are several causes of transverse myelitis. Known causes are optic neuritis and multiple sclerosis. It could also be caused by aortic dissection which extends to the spinal arteries as well as viruses like cytomegalovirus, herpes simplex, HIV, Epstein-Barr virus, rabies, enteroviruses and human T-cell leukemia virus. Bacterial infections like tuberculosis, syphilis and Lyme borreliosis have also been implicated along with conditions like paraneoplastic syndrome, and vascular causes like thrombosis of spinal artery, spinal arteriovenous malformations and vasculitis caused by heroin use [2].
Epidemiology
It is a fairly rare condition with the incidence thought to be up to 8 new cases per million per year. It has a bimodal peak age incidence occurring mostly between 10 – 19 years and 30 – 39 years, although it may occur at any age. About 25% of transverse myelitis patients are children and it has no familial association. It has no gender predilection. Most cases are monophasic, occurring just once, but there is recurrence in a minute number of patients and this is mostly due to a predisposing underlying illness [3].
Pathophysiology
- Multiple sclerosis is an autoimmune disease that occurs when T-cells are activated against unknown antigen which produces a cascade of inflammation that leads to demyelination and also axonal loss.
- Optic neuritis on the other hand involves the B-cells. These B-cells produce a substance, anti-aquaporin-4 antibodies which activate the complement system and cause the nerves to lose their myelin sheaths.
- Most idiopathic transverse myelitis are para-infections which has led to the belief that the immune response against the offending organism causes an autoimmune attack on myelin and some other antigens in the spinal cord. Mechanisms of injury could be molecular mimicry, where T-cells or antibodies found on these infectious agents cross-react with those in the central nervous system. Another mechanism could be a super-antigen response by the offending organism [4].
Prevention
There is no known way to prevent the primary attack. Recurrent attacks can be prevented with the use of immunosuppressants [10].
Summary
The origin of the name of this disorder is derived from the Greek word myelos which means spinal cord and the suffix –itis which means inflammation. Transverse implies that it spans the thickness of the cord. Nerve fibers are responsible for conducting electrical impulses and the myelinated fibers conduct these impulses better. In transverse myelitis, these myelin sheaths are destroyed [1].
Patient Information
Definition: Transverse myelitis is a disease of the spinal cord in which the nerves lose their ability to conduct electrical impulses leading to loss of many important daily nervous functions.
Cause: It can be caused by one of several autoimmune diseases. It can also be due to viral and bacterial infections. Some disorders of the arteries have also been known to cause it and it may also be brought about by heroin use.
Symptoms: Symptoms include pain of the legs as well as tingling, numbing and tickling sensations. There is also weakness of the leg muscles which may graduate to full paralysis. There will be loss of bladder and bowel function and in some patients, there will be respiratory difficulty.
Diagnosis: This is done with imaging techniques like MRI and CT scans which will show lesions of the brain and/or spinal cord. Blood tests will also be done to check for underlying diseases and part of the cerebrospinal fluid will be checked.
Treatment: This condition has no known cure but steroids are used to manage the inflammatory process. Plasma exchange therapy is used in patients who don't respond to steroids. Cyclophosphamide can be used in severe cases that don’t respond to any of the above.
References
- Altrocchi PH. Acute Transverse Myelopathy. Arch Neurol 1963; 9:111.
- Borchers AT, Gershwin ME. Transverse myelitis. Autoimmun Rev 2012; 11:231.
- Paine RS, Byers RK. Transverse myelopathy in childhood. AMA Am J Dis Child 1953; 85:151.
- Torabi AM, Patel RK, Wolfe GI, et al. Transverse myelitis in systemic sclerosis. Arch Neurol 2004; 61:126.
- Christensen PB, Wermuth L, Hinge HH, Bømers K. Clinical course and long-term prognosis of acute transverse myelopathy. Acta Neurol Scand 1990; 81:431.
- Oh DH, Jun JB, Kim HT, et al. Transverse myelitis in a patient with long-standing ankylosing spondylitis. Clin Exp Rheumatol 2001; 19:195.
- Bakshi R, Kinkel PR, Mechtler LL, et al. Magnetic resonance imaging findings in 22 cases of myelitis: comparison between patients with and without multiple sclerosis. Eur J Neurol 1998; 5:35.
- Wolf VL, Lupo PJ, Lotze TE. Pediatric acute transverse myelitis overview and differential diagnosis. J Child Neurol 2012; 27:1426.
- Bruna J, Martínez-Yélamos S, Martínez-Yélamos A, et al. Idiopathic acute transverse myelitis: a clinical study and prognostic markers in 45 cases. Mult Scler 2006; 12:169.
- Tippett DS, Fishman PS, Panitch HS. Relapsing transverse myelitis. Neurology 1991; 41:703.