Transverse
myelitis is a neurological disorder caused by inflammation across both
sides of one level, or segment, of the spinal cord. The term
myelitis refers to inflammation of the spinal cord;
transverse simply describes the position of the inflammation,
that is, across the width of the spinal cord. Attacks of inflammation can
damage or destroy myelin, the fatty insulating substance that covers nerve
cell fibers. This damage causes nervous system scars that interrupt
communications between the nerves in the spinal cord and the rest of the
body.
Symptoms of transverse myelitis include a loss of spinal cord function
over several hours to several weeks. What usually begins as a sudden onset
of lower back pain, muscle weakness, or abnormal sensations in the toes
and feet can rapidly progress to more severe symptoms, including
paralysis, urinary retention, and loss of bowel control. Although some
patients recover from transverse myelitis with minor or no residual
problems, others suffer permanent impairments that affect their ability to
perform ordinary tasks of daily living. Most patients will have only one
episode of transverse myelitis; a small percentage may have a
recurrence.
The segment of the spinal cord at which the damage occurs determines
which parts of the body are affected. Nerves in the cervical (neck) region
control signals to the neck, arms, hands, and muscles of breathing (the
diaphragm). Nerves in the thoracic (upper back) region relay signals to
the torso and some parts of the arms. Nerves at the lumbar (mid-back)
level control signals to the hips and legs. Finally, sacral nerves,
located within the lowest segment of the spinal cord, relay signals to the
groin, toes, and some parts of the legs. Damage at one segment will affect
function at that segment and segments below it. In patients with
transverse myelitis, demyelination usually occurs at the thoracic level,
causing problems with leg movement and bowel and bladder control, which
require signals from the lower segments of the spinal cord.
Transverse myelitis
occurs in adults and children, in both genders, and in all races. No
familial predisposition is apparent. A peak in incidence rates (the number
of new cases per year) appears to occur between 10 and 19 years and 30 and
39 years. Although only a few studies have examined incidence rates, it is
estimated that about 1,400 new cases of transverse myelitis are diagnosed
each year in the United States, and approximately 33,000 Americans have
some type of disability resulting from the disorder.
Researchers
are uncertain of the exact causes of transverse myelitis. The inflammation
that causes such extensive damage to nerve fibers of the spinal cord may
result from viral infections, abnormal immune reactions, or insufficient
blood flow through the blood vessels located in the spinal cord.
Transverse myelitis also may occur as a complication of syphilis, measles,
Lyme disease, and some vaccinations, including those for chickenpox and
rabies. Cases in which a cause cannot be identified are called
idiopathic.
Transverse myelitis often develops following viral infections.
Infectious agents suspected of causing transverse myelitis include
varicella zoster (the virus that causes chickenpox and shingles), herpes
simplex, cytomegalovirus, Epstein-Barr, influenza, echovirus, human
immunodeficiency virus (HIV), hepatitis A, and rubella. Bacterial skin
infections, middle-ear infections (otitis media), and
Mycoplasma pneumoniae (bacterial pneumonia) have also been
associated with the condition.
In post-infectious cases of transverse myelitis, immune system
mechanisms, rather than active viral or bacterial infections, appear to
play an important role in causing damage to spinal nerves. Although
researchers have not yet identified the precise mechanisms of spinal cord
injury in these cases, stimulation of the immune system in response to
infection indicates that an autoimmune reaction may be responsible. In
autoimmune diseases, the immune system, which normally protects the body
from foreign organisms, mistakenly attacks the body’s own tissue, causing
inflammation and, in some cases, damage to myelin within the spinal
cord.
Because some affected individuals also have autoimmune diseases such as
systemic lupus erythematosus, Sjogren’s syndrome, and sarcoidosis, some
scientists suggest that transverse myelitis may also be an autoimmune
disorder. In addition, some cancers may trigger an abnormal immune
response that may lead to transverse myelitis.
An acute, rapidly progressing form of transverse myelitis sometimes
signals the first attack of multiple sclerosis (MS), however, studies
indicate that most people who develop transverse myelitis do not go on to
develop MS. Patients with transverse myelitis should nonetheless be
screened for MS because patients with this diagnosis will require
different treatments.
Some cases of transverse myelitis result from spinal arteriovenous
malformations (abnormalities that alter normal patterns of blood flow) or
vascular diseases such as atherosclerosis that cause ischemia, a
reduction in normal levels of oxygen in spinal cord tissues. Ischemia can
result from bleeding (hemorrhage) within the spinal cord, blood
vessel blockage or narrowing, or other less common factors. Blood vessels
bring oxygen and nutrients to spinal cord tissues and remove metabolic
waste products. When these vessels become narrowed or blocked, they cannot
deliver sufficient amounts of oxygen-laden blood to spinal cord tissues.
When a specific region of the spinal cord becomes starved of oxygen, or
ischemic, nerve cells and fibers may begin to deteriorate relatively
quickly. This damage may cause widespread inflammation, sometimes leading
to transverse myelitis. Most people who develop the condition as a result
of vascular disease are past the age of 50, have cardiac disease, or have
recently undergone a chest or abdominal operation.
Transverse myelitis may be either acute
(developing over hours to several days) or subacute (developing
over 1 to 2 weeks). Initial symptoms usually include localized lower back
pain, sudden paresthesias (abnormal sensations such as burning,
tickling, pricking, or tingling) in the legs, sensory loss, and
paraparesis (partial paralysis of the legs). Paraparesis often
progresses to paraplegia (paralysis of the legs and lower part of
the trunk). Urinary bladder and bowel dysfunction is common. Many patients
also report experiencing muscle spasms, a general feeling of discomfort,
headache, fever, and loss of appetite. Depending on which segment of the
spinal cord is involved, some patients may experience respiratory problems
as well.
From this wide array of symptoms, four classic features of transverse
myelitis emerge: (1) weakness of the legs and arms, (2) pain, (3) sensory
alteration, and (4) bowel and bladder dysfunction. Most patients will
experience weakness of varying degrees in their legs; some also experience
it in their arms. Initially, people with transverse myelitis may notice
that they are stumbling or dragging one foot or that their legs seem
heavier than normal. Coordination of hand and arm movements, as well as
arm and hand strength may also be compromised. Progression of the disease
over several weeks often leads to full paralysis of the legs, requiring
the patient to use a wheelchair.
Pain is the primary presenting symptom of transverse myelitis in
approximately one-third to one-half of all patients. The pain may be
localized in the lower back or may consist of sharp, shooting sensations
that radiate down the legs or arms or around the torso.
Patients who experience sensory disturbances often use terms such as
numbness, tingling, coldness, or burning to describe
their symptoms. Up to 80 percent of those with transverse myelitis report
areas of heightened sensitivity to touch, such that clothing or a light
touch with a finger causes significant discomfort or pain (a condition
called allodynia). Many also experience heightened sensitivity to
changes in temperature or to extreme heat or cold.
Bladder and bowel problems may involve increased frequency of the urge
to urinate or have bowel movements, incontinence, difficulty voiding, the
sensation of incomplete evacuation, and constipation. Over the course of
the disease, the majority of people with transverse myelitis will
experience one or several of these symptoms.
Physicians diagnose transverse myelitis by taking a
medical history and performing a thorough neurological examination.
Because it is often difficult to distinguish between a patient with an
idiopathic form of transverse myelitis and one who has an underlying
condition, physicians must first eliminate potentially treatable causes of
the condition. If a spinal cord injury is suspected, physicians seek first
to rule out lesions (damaged or abnormally functioning areas)
that could cause spinal cord compression. Such potential lesions include
tumors, herniated or slipped discs, stenosis (narrowing of the
canal that holds the spinal cord), and abscesses. To rule out such lesions
and check for inflammation of the spinal cord, patients often undergo
magnetic resonance imaging (MRI), a procedure that provides a
picture of the brain and spinal cord. Physicians also may perform
myelography, which involves injecting a dye into the sac that
surrounds the spinal cord. The patient is then tilted up and down to let
the dye flow around and outline the spinal cord while X-rays are taken.
Blood tests may be performed to rule out various disorders such as
systemic lupus erythematosus, HIV infection, and vitamin B12 deficiency.
In some patients with transverse myelitis, the cerebrospinal fluid that
bathes the spinal cord and brain contains more protein than usual and an
increased number of leukocytes (white blood cells), indicating possible
infection. A spinal tap may be performed to obtain fluid to study these
factors.
If none of these tests suggests a specific cause, the patient is
presumed to have idiopathic transverse myelitis.
As with
many disorders of the spinal cord, no effective cure currently exists for
people with transverse myelitis. Treatments are designed to manage and
alleviate symptoms and largely depend upon the severity of neurological
involvement. Therapy generally begins when the patient first experiences
symptoms. Physicians often prescribe corticosteroid therapy during the
first few weeks of illness to decrease inflammation. Although no clinical
trials have investigated whether corticosteroids alter the course of
transverse myelitis, these drugs often are prescribed to reduce immune
system activity because of the suspected autoimmune mechanisms involved in
the disorder. Corticosteroid medications that might be prescribed may
include methylprednisone or dexamethasone. General analgesia will likely
be prescribed for any pain the patient may have. And bedrest is often
recommended during the initial days and weeks after onset of the disorder.
Following initial therapy, the most critical part of the treatment for
this disorder consists of keeping the patient’s body functioning while
hoping for either complete or partial spontaneous recovery of the nervous
system. This may sometimes require placing the patient on a respirator.
Patients with acute symptoms, such as paralysis, are most often treated in
a hospital or in a rehabilitation facility where a specialized medical
team can prevent or treat problems that afflict paralyzed patients. Often,
even before recovery begins, caregivers may be instructed to move
patients’ limbs manually to help keep the muscles flexible and strong, and
to reduce the likelihood of pressure sores developing in immobilized
areas. Later, if patients begin to recover limb control, physical therapy
begins to help improve muscle strength, coordination, and range of motion.
Many forms of long-term
rehabilitative therapy are available for people who have permanent
disabilities resulting from transverse myelitis. Medical social workers,
often affiliated with local hospitals or outpatient clinics, are the best
sources for information about treatment programs and other resources that
exist in a community. Rehabilitative therapy teaches people strategies for
carrying out activities in new ways in order to overcome, circumvent, or
compensate for permanent disabilities. Rehabilitation as yet cannot
reverse the physical damage resulting from transverse myelitis or other
forms of spinal cord injury. But it can help people, even those with
severe paralysis, become as functionally independent as possible and
thereby attain the best possible quality of life.
Commonly experienced permanent neurological deficits resulting from
transverse myelitis include severe weakness, spasticity (painful
muscle stiffness or contractions), or paralysis; incontinence; and chronic
pain. Such deficits can substantially interfere with a person’s ability to
carry out everyday activities such as bathing, dressing, and performing
household tasks.
People living with permanent disability may feel a range of emotions,
from fear and sadness to frustration and anger. Such feelings are natural
responses, but they can sometimes jeopardize health and potential for
functional recovery. Those with permanent disabilities frequently
experience clinical depression. Fortunately, depression is treatable, due
to the development of a wide range of medications that can be used with
psychotherapeutic treatment.
Today, most rehabilitation programs attempt to address the emotional
dimensions along with the physical problems resulting from permanent
disability. Patients typically consult with a range of rehabilitation
specialists, who may include physiatrists (physicians specializing in
physical medicine and rehabilitation), physical therapists, occupational
therapists, vocational therapists, and mental health care
professionals.
Physical Therapy: Physiatrists and physical
therapists treat disabilities that result from motor and sensory
impairments. Their aim is to help patients increase their strength and
endurance, improve coordination, reduce spasticity and muscle wasting in
paralyzed limbs, and regain greater control over bladder and bowel
function through various exercises. Physiatrists and physical therapists
teach paralyzed patients techniques for using assistive devices such as
wheelchairs, canes, or braces as effectively as possible. Paralyzed
patients also learn ways to avoid developing painful pressure sores on
immobilized parts of the body, which may lead to increased pain or
systemic infection. In addition, physiatrists and physical therapists are
involved in pain management. A wide variety of drugs now exist that can
alleviate the pain that results from spinal cord injuries such as those
caused by transverse myelitis. These include nonsteroidal
anti-inflammatory drugs such as ibuprofen or naproxen; antidepressant
drugs such as amitryptyline (tricyclic) and sertraline (a selective
serotonin reuptake inhibitor); and anticonvulsant drugs such as phenytoin
and gabapentine.
Occupational Therapy: Occupational therapists
help patients learn new ways of performing meaningful, self-directed,
goal-oriented, everyday tasks (occupations) such as bathing,
dressing, preparing a meal, house cleaning, engaging in arts and crafts,
or gardening. They teach people how to develop compensatory strategies,
how to make changes in their homes to improve safety (such as installing
grab bars in bathrooms), how to change obstacles in their environment that
interfere with normal activity, and how to use assistive devices.
Vocational Therapy: In addition to
acquainting people with their rights as defined under the Americans with
Disabilities Act of 1990 and helping people develop and promote work
skills, vocational therapists identify potential employers, assist in job
searches, and act as mediators between employees and employers to secure
reasonable workplace accommodations.
Recovery from
transverse myelitis usually begins within 2 to 12 weeks of the onset of
symptoms and may continue for up to 2 years. However, if there is no
improvement within the first 3 to 6 months, significant recovery is
unlikely. About one-third of people affected with transverse myelitis
experience good or full recovery from their symptoms; they regain the
ability to walk normally and experience minimal urinary or bowel effects
and paresthesias. Another one-third show only fair recovery and are left
with significant deficits such as spastic gait, sensory dysfunction, and
prominent urinary urgency or incontinence. The remaining one-third show no
recovery at all, remaining wheelchair-bound or bedridden with marked
dependence on others for basic functions of daily living. Unfortunately,
making predictions about individual cases is difficult. However, research
has shown that a rapid onset of symptoms generally results in poorer
recovery outcomes.
The majority of people with this disorder experience only one episode
although in rare cases recurrent or relapsing transverse myelitis does
occur. Some patients recover completely, then experience a relapse. Others
begin to recover, then suffer worsening of symptoms before recovery
continues. In all cases of relapse, physicians will likely investigate
possible underlying causes such as MS or systemic lupus erythematosus
since most people who experience relapse have an underlying disorder.
Within the
Federal Government, the National Institute of Neurological Disorders and
Stroke (NINDS), one of the National Institutes of Health (NIH), has
primary responsibility for conducting and supporting research on spinal
cord disorders and demyelinating diseases such as transverse myelitis. The
NINDS conducts research in its laboratories at the NIH and also supports
studies through grants to major medical institutions across the country.
NINDS researchers seek to clarify the role of the immune system in the
pathogenesis of demyelination in autoimmune diseases or disorders. Other
work focuses on strategies to repair demyelinated spinal cords including
approaches using cell transplantation. The knowledge gained from such
research should lead to a greater knowledge of the mechanisms responsible
for demyelination in transverse myelitis and may ultimately provide a
means to prevent and treat this disorder.
The NINDS also funds researchers who are using animal models of spinal
cord injury to study strategies for replacement or regeneration of spinal
cord nerve cells. The ultimate goals of these studies are to encourage the
same regeneration in humans and to restore function to paralyzed patients.
Scientists are also developing neural prostheses to help patients with
spinal cord damage compensate for lost function. These sophisticated
electrical and mechanical devices connect with the nervous system to
supplement or replace lost motor and sensory function. Neural prostheses
for spinal cord injured patients are being tested in humans.
Keeping on Top of Your Condition
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For more information on transverse myelitis and the symptoms associated
with the disorder, you may wish to contact:
American Chronic Pain Association
P. O. Box 850
Rocklin,
California 95677-0850
(916) 632-0922
http://www.theacpa.org/
Christopher Reeve Paralysis Foundation
500 Morris
Avenue
Springfield, New Jersey 07081
(973) 379-2690
(800)
225-0292
http://www.paralysis.org/
Kent Waldrep National Paralysis Foundation
16415 Addison Road, Suite
550
Addison, Texas 75001
(972) 248-7100
(800) SCI-CURE
(925-2873)
http://www.spinalvictory.org/
Miami Project to Cure Paralysis/Buoniconti Fund
P.O. Box 016960,
R-48
Miami, Florida 33101
(305) 243-6001
(800) STANDUP
(782-6387)
http://www.themiamiproject.org/
National Chronic Pain Outreach Association
P.O. Box 274
Millboro,
Virginia 24460
(540) 862-9437
Transverse Myelitis Association
1787 Sutter Parkway
Powell, Ohio
43065-8806
(614) 766-1806
http://www.myelitis.org/
For information on rehabilitation, you may wish to contact:
National Rehabilitation Information Center (NARIC)
4200 Forbes
Boulevard, Suite 202
Lanham, MD 20706-4829
(301) 562-2400
(800)
346-2742
naricinfo@heitechservices.com
http://www.naric.com/
BRAIN
P.O. Box 5801
Bethesda, Maryland 20824
(301)
496-5751
(800) 352-9424
http://www.ninds.nih.gov/
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