Myelitis and Acute Transverse Myelitis - Causes, Symptoms and Treatment

Definition:

Myelitis, or inflammation of the spinal cord, can result from several diseases. Poliomyelitis affects the cord's gray matter and produces motor dysfunction; leukomyelitis affects only the white matter and produces sensory dysfunction. These types of myelitis can attack any level of the spinal cord, causing partial destruction or scattered lesions. Acute transverse myelitis, which affects the entire thickness of the spinal cord, produces both motor and sensory dysfunctions. This form of myelitis, which has a rapid onset, is the most devastating.

Prognosis depends on the severity of cord damage and prevention of complications. If spinal cord necrosis occurs, the prognosis for complete recovery is poor. Even without necrosis, residual neurologic deficits usually persist after recovery. Patients who develop spastic reflexes early in the course of the illness are more likely to recover than those who do not develop spastic reflexes or develop them at a later point in the illness.

Causes of Myelitis

Acute transverse myelitis has a variety of causes. It often follows acute infectious diseases, such as measles or pneumonia the inflammation occurs after the infection has subsided), and primary infections or the spinal cord itself, such as syphilis or acute disseminated encephalomyelitis. Acute transverse myelitis can accompany demyelinating diseases, such as acute multiple sclerosis, and inflammatory and necrotizing disorders of the spinal cord, such as hematomyelia.

Certain toxic agents (carbon monoxide, lead, and arsenic) can cause a type of myelitis in which acute inflammation (followed by hemorrhage and possible necrosis) destroys the entire circumference (myelin, axis cylinders, and neurons) of the spinal cord. Other forms of myelitis may result from poliovirus, herpes zoster, herpes virus B, or rabies virus; disorders that cause meningeal inflammation, such as syphilis, abscesses and other suppurative conditions, and tuberculosis; smallpox or polio vaccination; parasitic and fungal infections; and chronic adhesive arachnoiditis.

Signs and Symptoms of Myelitis

In acute transverse myelitis, onset is rapid, with motor and sensory dysfunctions below the level of spinal cord damage appearing in 1 to 2 days. Patients with acute transverse myelitis develop flaccid paralysis of the legs (sometimes beginning in just one leg) with loss of sensory and sphincter functions. Such sensory loss may follow pain in the legs or trunk. Reflexes disappear in the early stages but may reappear later. The extent of damage depends on which level of the spinal cord is affected; transverse myelitis rarely involves the arms. If spinal cord damage is severe, it may cause shock (hypotension and hypothermia).

Diagnosis for Myelitis

Paraplegia of rapid onset usually points to acute transverse myelitis. In such patients, neurologic examination confirms paraplegia or ncurologic deficit below the level of the spinal cord lesion and absent or, later, hyperactive reflexes. Cerebrospinal fluid may be normal or show increased lymphocyte or protein levels. Diagnostic evaluation must rule out a spinal cord tumor and identify the cause of any underlying infection.

Treatment for Myelitis

No effective treatment exists for acute transverse myelitis. However, this condition requires appropriate treatment of any underlying infection. Some patients with postinfectious or multiple sclerosis-induced myelitis have received steroid therapy, but its benefits aren't clear.

Special Considerations and Prevention Tips for Myelitis

Prevention of complications is important. Prevent contractures with range-of-motion exercises and proper alignment. Prevent skin infections and pressure ulcers with meticulous skin care. Check pressure points often, keep skin clean and dry, and use a waterbed or another pressure-relieving device.

1. Assess vital signs frequently. Watch carefully for signs of spinal shock (hypotension and excessive sweating).

2. Watch for signs of urinary tract infections from indwelling urinary catheters.