Transverse myelitis (TM) is an inflammatory condition across the spinal cord, along one or more levels and in the absence of compression. Idiopathic acute TM is rare and with improvements in diagnostic tools and longer follow-up, the etiology which may include post-infectious, multiple sclerosis, or neuromyelitis optica often becomes clearer. The patient may present acutely with weakness, sensory impairments, or bowel and bladder changes. A careful history, physical examination, and appropriate diagnostic studies including blood tests and an MRI scan may help determine the diagnosis and etiology. Following the acute management, which may include use of steroids, immunosuppressive drugs, and plasma exchange, a comprehensive medical rehabilitation program is important to optimize recovery from the resultant impairments and disabilities and manage associated complications. Complications such as paralysis, autonomic dysfunction, neuropathic and musculoskeletal pain, spasticity, contractures, neurogenic bladder and bowels, skin breakdown, and psychological issues will benefit from the expertise of the physiatrist. Rehabilitation will include functional restoration with therapy as well as compensation of residual impairment with mobility and various other assistive devices.
Keywordsneurological inflammatory condition, paralysis, rehabilitation, spinal cord injury, transverse myelitis
|G37.3||Acute transverse myelitis in demyelinating disease of central nervous system (Acute transverse myelitis NOS)|
|TM may also have been coded as:|
|G04.0||Acute disseminated encephalitis (Encephalitis and Encephalomyelitis: postimmunization)|
|G04.8||Other encephalitis, myelitis and encephalomyelitis (Postinfectious encephalitis and encephalomyelitis NOS)|
|G05.0||Encephalitis, myelitis or encephalomyelitis in bacterial diseases classified elsewhere|
|G05.1||Encephalitis, myelitis or encephalomyelitis in viral diseases classified elsewhere|
|G05.2||Encephalitis, myelitis or encephalomyelitis in other infectious and parasitic diseases classified elsewhere|
|G05.8||Encephalitis, myelitis or encephalomyelitis in other diseases classified elsewhere|
|G36.0||Neuromyelitis optica (Devic)|
|G82.2||Paraplegia, unspecified (Paralysis of both lower limbs NOS, Paraplegia [lower] NOS)|
|G82.5||Tetraplegia, unspecified (Quadriplegia NOS)|
Transverse myelitis (TM) is a focal inflammation across the spinal cord along one or more levels, in the absence of a compressive lesion. This inflammation can cause damage to the ensheathing nerve cell fiber myelin, with resultant neurological dysfunction including weakness, sensory impairments, and autonomic problems including the bowel and bladder. The diagnosis may incorporate the terms idiopathic, where no specific bacterial, viral, or other obvious inflammatory cause can be found, or secondary, where there is an antecedent or associated disease. Other commonly encountered descriptors include acute, acute partial, acute complete, and longitudinally extensive . There are few population-based studies available, and comparative or meta-analysis of the literature is difficult because of the various presentations of TM being reported. It appears, however, that acute TM is rare with only 1400 new cases annually in the United States, or 1.34 to 4.6 cases per million population per year. With availability of improved diagnostic tools, unveiling of the disease over time and longer follow-up periods, the etiology often becomes clearer, including those originally labeled as idiopathic . An older study from 1993 in the United States on acute or subacute noncompressive myelopathy reported that 45% of the cases were parainfectious, 21% multiple sclerosis, 12% spinal cord ischemia, and 21% idiopathic. A 2005 French multicenter retrospective study applying the TM Consortium Working Group criteria for acute TM to 288 subjects had a more even spread. Systemic disease (systemic lupus erythematosus, Sjögren syndrome, antiphospholipid syndrome) was implicated in 20.5%, spinal cord infarct in 18.8%, multiple sclerosis 10.8%, infectious or parainfectious 17.3%, neuromyelitis optica 17%, and idiopathic acute TM 15.6%. Another study from France in 2012 on acute partial TM with median follow-up period of 104.8 months reported etiology of the cases as being 62% multiple sclerosis, 1% postinfectious myelitis, 1% neuromyelitis optica, 1% Sjögren syndrome, and 34% undetermined or idiopathic.
There is a female predominance of about 60% to 75% and a bimodal age distribution in the second and fourth decades. Patients having TM related to multiple sclerosis, post-infectious TM, or idiopathic TM are younger, whereas those with TM related to spinal cord infarcts or delayed radiation effects are older. TM may recur, with reported rates ranging from 17.5% to 61%, and relapse appears to be more common with acute partial TM.
According to one magnetic resonance imaging (MRI) study, idiopathic acute TM most commonly affects the cervical region (60%), followed by the thoracic region (33%). The onset of TM can be acute (within hours or days) or subacute (between 1 and 4 weeks). The period from onset to maximum weakness in idiopathic TM has been reported to range from 10 hours to 28 days, with a mean of 5 days. Subacute presentations, progressing over days to weeks and ascending, are associated with a good to fair prognosis. Acute and catastrophic presentations with back pain have a poorer outcome.
Recovery is often related to the clinical presentation and may or may not be complete. In general, one third of patients with acute TM make a good recovery, another third have fair recovery, and the rest either fail to improve or die. In idiopathic TM treated with methylprednisolone using the Medical Research Council (MRC) scale for muscle strength, 37.5% were reported to have complete recovery or minimal residual deficit (MRC 5-4), 43% had partial recovery (MRC 3), and 19.4% had severe disability or absent recovery (MRC 0-2). Factors associated with poor outcomes include severe initial symptoms with spinal shock, delayed presentation to the hospital after maximum deficits have already occurred, development of syringomyelia, and extensive MRI lesions. If no recovery has occurred by 1 to 3 months, complete recovery is less likely.
Patients with TM may present in the ambulatory clinic, urgent care center, or hospital setting with complaints of weakness of the limbs sensory impairments, pain, and difficulties with the bowel and bladder. Weakness may affect only the lower limbs or all four limbs with varying severity. It may be complete, incomplete, or may present as one of the spinal cord syndromes. The clinical spinal level usually corresponds to the lesion, but lower limb findings do not preclude a lesion at the cervical level. Sensory complaints may include hypersensitivity, numbness, tingling, coldness, burning, or as a circumferential constriction. Pain is a common symptom in one third to one half of patients and may be central or localized, aching or radicular in character. Bowel frequency or constipation may occur, and bladder symptoms include increased frequency, retention, and incontinence.
The history, including past medical, family, and detailed social, may reveal symptoms of recent infection, immunocompromised or autoimmune condition, space-occupying lesion, demyelinating disease, travel, vaccination, trauma, sexual exposure, animal, insect or tick bites. Whether vaccination triggers TM has been debated. There were only seven cases of TM and eight of acute disseminated encephalomyelitis (ADEM) in the primary vaccination exposure window of 5 to 18 days prior to onset after 64 million doses within a healthcare network. The incidences were both nonstatistically significant except ADEM with Tdap (tetanus, diphtheria, and pertussis) vaccine at P = .04 (translating into 1.16 cases per million doses).
A careful review may yield systemic symptoms, including the upper respiratory tract with cough and difficulty in breathing, chest pain, rashes, joint aches, muscle pain, vision changes, nausea, diarrhea, constipation, and problems with urinary function. Particular attention should be paid to details pointing toward potentially treatable or reversible conditions responsive to antimicrobials or surgical decompression.
There may be a history of invasive spinal intervention for pain management, and TM relating to the infected catheter tip of an intrathecal morphine pump for chronic pain has been reported.
The physical examination should be broadly systemic as well as focused on neurological findings such as motor weakness, changes in sensation (pinprick, light touch, vibration, position sense, or temperature), tone, muscle stretch reflexes, coordination, and bowel and bladder functioning. Changes affecting the brain, such as cognitive dysfunction and cranial nerve and visual abnormalities, are generally not seen with idiopathic TM.
Fever, tachycardia, and tachypnea may indicate an infectious etiology. Infections, autoimmune, and other conditions that cause acute inflammation of the spinal cord may also manifest in the other body systems. Respiratory, cardiovascular, gastrointestinal, and genitourinary tracts as well as the musculoskeletal and integumentary systems should be assessed accordingly. The findings will assist in determining the level of spinal involvement, guide diagnostic testing, and help rule out other diagnoses.
The physiatrist is likely to encounter the patient as a consultation for rehabilitation assessment and management, or referral for a specific problem such as spasticity or pain intervention. The functional limitations in a patient with TM usually depend on the level of spinal cord involvement and corresponding muscles affected. Debilitation and deconditioning from associated illnesses and prolonged recumbency will also affect function secondarily.
The functional capability review according to spinal level may be influenced by whether the cord injury is unilateral or bilateral and the degree of completeness. High cervical lesions result in tetraplegia with sensory impairment and also affect the phrenic nerve (C3-C5) with diaphragmatic paralysis requiring mechanical ventilation. A patient with C4 innervation preserved may or may not have respiratory difficulties but will be dependent for most self-care activities. Using appropriate technology and devices, whether customized or commercially available, the patient may be able to control the home environment, summon assistance, direct their care, and mobilize in an electric wheelchair with a chin control or a sip-and-puff interface.
A patient with C5 level may be able to self-feed and perform personal grooming with equipment such as a universal cuff for the hand allowing attachment of tools (e.g., fork, spoon, or comb). The patient can independently use a powered wheelchair and propel a lightweight manual wheelchair with hand rim projections (“quad knobs”) for limited distances over level ground. C6 innervation allows independence with upper extremity dressing, bathing with equipment, and functional propulsion of a manual wheelchair indoors. The patient with superior balance and motor control could theoretically perform independent or supervised transfers with a sliding board, and self-catheterize with appropriate assistive devices. Driving a specially adapted automatic transmission vehicle with powered steering, hand-controlled accelerator and brake can be achieved with C7-C8 preservation. A C7 level allows independence in all self-care activities with equipment, independent transfers with ability to push off using intact elbow extensor muscles, and the patient may be able to live alone. A patient with C8 and T1 innervation will have improved manual strength and dexterity for self-care, is independent with a manual wheelchair, and should be able to self-catheterize. Preservation of upper thoracic innervation allows a greater degree of trunk control, increasing stability during use and propulsion of a manual wheelchair. It also adds to ease and independence with bladder and bowel self-management. With bracing of the hips, knees, and ankles (KAFO or knee-ankle-foot orthoses), minimal ambulation can be attempted, although mainly for training and exercise purposes than truly functional. Independent ambulation, even with bracing and bilateral axillary or forearm crutches, is usually not realistic unless the patient has preservation of some upper lumbar innervation. Further preservation of lumbar and sacral innervation will increase ease of ambulation with better trunk and pelvic control. The patient with incomplete spinal injury is less predictable, and functional abilities will largely depend on the degree and nature of neurologic preservation.
With increasingly greater resolutions and techniques such as T2-weighted fast spin-echo and short-tau inversion recovery (STIR) to enhance or suppress the appearance of fat and tissues of different densities, the best tool when TM is suspected is MRI. MRI not only allows visualization of the lesion but also rules out treatable causes, such as tumor, abscess, and other lesions causing compressive myelopathy. Contrast material can be given to highlight lesions, and myelography may rarely be considered if MRI is not available.
MRI scans show features that help differentiate TM from disorders such as multiple sclerosis ( Figs. 162.1 and 162.2 ). The lesion in TM tends to affect the central region of the cord and involve more than two thirds of the cord diameter, whereas in multiple sclerosis it is usually more peripheral and involves less than half of the cord diameter. TM is more often associated with high signal intensity on T2-weighted images extending longitudinally over more segments. The number of segments involved may be from 1 or 2 up to 11, and the entire cord or sometimes only the medulla may be affected. The lesion in TM at times resembles a spinal cord tumor and biopsy may even be attempted during investigation.
MRI of the brain with contrast enhancement is often performed to help determine whether the MRI findings point toward multiple sclerosis rather than “idiopathic” TM. In idiopathic partial TM, a study that does not show brain lesions translates to the likelihood of evolving multiple sclerosis at 15% to 44%. When brain lesions such as white matter plaques (especially periventricular) are seen, the chance for development of multiple sclerosis increases to 44% to 93%. Asymmetric motor or sensory symptoms and absence of peripheral nervous system involvement at presentation suggest acute myelopathic multiple sclerosis, whereas symmetric symptoms and peripheral nervous system involvement suggest acute TM.
Immunoglobulin G antibodies may be useful for determining neuromyelitis optica (Devic’s disease) as the etiology in patients with acute complete TM. Longitudinally extensive TM spanning three or more vertebral segments is an important feature and detection of anti-aquaporin 4-specific antibodies (anti-AQP4, AQ4P-Ab, or NMO-IgG) is useful to determine both increased risk for recurrence and conversion to neuromyelitis optica.
Other tests include the usual blood counts and chemistry, tests for autoimmune conditions such as antinuclear antibodies, anti-double-stranded DNA antibodies, anti-Sm antibodies, erythrocyte sedimentation rate, SS-A antibody for Sjögren disease, immunoglobulin levels, and VDRL. Vitamin B 12 levels may be tested, and Mycoplasma pneumoniae or Mycobacterium tuberculosis cultures may be performed. Lyme titers and titers for various viruses including human immunodeficiency virus, West Nile virus, poliovirus, hepatitis virus, Epstein-Barr virus, cytomegalovirus, and enteric cytopathic human orphan virus may be elevated. The polymerase chain reaction (PCR) technique is useful for amplifying minute quantities of DNA or RNA. It was used in a recent case report on acute myelitis caused by Zika virus infection, which responded well to high-dose prednisolone.
A lumbar puncture allows assessment of cerebrospinal fluid pressure, and samples for cell count, determination of protein and glucose concentrations, measurement of immunoglobulins, and protein electrophoresis. Oligoclonal bands detected in cerebrospinal fluid are useful in making a diagnosis. In one report, they were present in three of five patients with multiple sclerosis-associated TM, but in none of four patients with parainfectious TM. Nerve conduction studies (NCS), electromyography (EMG), as well as somatosensory and motor evoked potentials may be useful for establishing diagnosis and monitoring progress. Urinary system evaluation including cystourethrography, cystoscopy, a baseline renal ultrasound, and urodynamic studies with or without video, have been recommended because of the very high rates of persistent long-term bladder dysfunction. Bowel evaluation may require radiography, computed tomography (CT), and MRI scans with or without contrast, or colonoscopy to rule out obstruction. In 2002, the TM Consortium Working Group proposed the criteria in Table 162.1 for the diagnosis of idiopathic acute TM.
|Inclusion Criteria||Exclusion Criteria|