Transverse myelitis overview

# Overview
Transverse myelitis is a neurological disorder caused by an inflammatory process of the grey and white matter of the spinal cord, and can cause axonal demyelination.

# Pathophysiology
Axonal demyelination arises idiopathically following infections or vaccination, or due to multiple sclerosis. One major theory of the cause is that an immune-mediated inflammation is present as the result of exposure to a viral antigen. The lesions are inflammatory, and involve the spinal cord on both sides.

# Natural History, Complications and Prognosis
Prognosis for complete recovery is generally poor. Recovery from transverse myelitis usually begins between weeks 2 and 12 following onset and may continue for up to 2 years in some patients, many of whom are left with considerable disabilities. Some patients show no signs of recovery whatsoever.

# Diagnosis

## Laboratory Findings
Blood tests may be performed to rule out various disorders such as systemic lupus erythematosus, HIV infection,  vitamin B12 deficiency, and many others  A blood test for NMO, called NMO-IgG, is also necessary. 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).  A spinal tap may be performed to obtain fluid to study these factors, exclude infections, and to look for markers of diseases such as MS.

## CT
If an MRI is not possible (for example, if the patient has a pacemaker), physicians may consider other diagnostic tests such as computed tomography (CT) of the spine with or without myelography, which involves injecting a dye into the sac that surrounds the spinal cord.

## MRI
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. when a spinal cord problem is suspected, physicians seek first to rule out structural lesions (damaged or abnormally functioning areas) that could cause spinal cord compression or otherwise affects its function. Such potential lesions include tumors, herniated or slipped discs, stenosis (narrowing of the canal that holds the spinal cord), abscesses, and abnormal collections of blood vessels. 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. The spinal cord MRI will almost always confirm the presence of a lesion within the spinal cord, whereas the brain MRI may provide clues to other underlying causes, especially MS.

# Treatment

## Medical Therapy
Treatments are designed to reduce spinal cord inflammation and manage and alleviate symptoms. Initial therapy includes prescription of anti-inflammatorycorticosteroid therapy soon after the diagnosis is made in order to decrease inflammation and hopefully improve the chances and speed of neurological recovery. In severe cases that do not appear to respond to corticosteroid treatment, other therapies such as plasma exchange or drug therapies may be used to try to salvage neurological function. Later, if patients begin to recover limb control,physical therapy begins to help improve muscle strength,coordination, and range of motion.