Sensorimotor polyneuropathy

Causes and Risks:
Sensorimotor polyneuropathy is a form of peripheral neuropathy (damage to nerves not including the brain or spinal cord). It is not a separate disorder, but a manifestation of many conditions involving damage to multiple peripheral nerves (polyneuropathy).

Sensorimotor polyneuropathy implies a systemic process that damages nerves. This damage may include loss of the myelin sheath, the covering of the nerve cell, which slows conduction through the nerve. It may also include damage to the nerve cell, especially the axon portion of the cell, which blocks conduction at the point of the damage.

Causes of damage to nerves include any condition that results in pressure on nerves, inflammation, decreased blood flow, connective tissue disorders, and similar conditions. There is a high degree of variability in the disorders that can cause sensorimotor polyneuropathy, from acute or chronic conditions to unknown causes. Some examples include alcoholic neuropathy , diabetic neuropathy , chronic inflammatory neuropathy, Guillain-Barre syndrome , and neuropathy secondary to drugs .

Prevention:
Prevention varies depending on the cause.

Symptoms:

Note: The symptoms may develop gradually (over weeks to years) and usually occur on both sides of the body and progress from distal (far) areas to proximal (central) portions of the body.

Signs and Tests:
A neuromuscular examination shows sensory and movement abnormalities. There is a slowly progressive pattern to the history of weakness or sensation changes. Sensation deficits usually occur in a symmetrical pattern and progress from distal (far) areas to proximal (central) locations. The reflexes may be decreased or absent. Muscle weakness or paralysis of the affected area may be present. A muscle twitch ( fasciculations ) or muscle atrophy may be apparent.

An EMG (a test of electrical activity in muscles) may indicate the type and degree of peripheral nerve injury. Nerve conduction tests may indicate the loss of the myelin sheath (slow conduction rate) or degeneration of the axon of the nerve cell (normal conduction rate).

Other tests are guided by the suspected cause of the disorder, as suggested by the history, symptoms presented, and pattern of symptom development. They may include various X-rays, scans, blood tests, or other tests and procedures.

Treatment:
The goals of treatment include treatment of the cause if possible, supportive care to maximize self care ability and independence, and control of symptoms.

The cause should be identified and treated whenever possible. This may include such things as the control of blood sugar levels for diabetics, abstinence from alcohol, and taking daily nutritional supplements.

Maximize self care and independence:
Physical therapy, vocational therapy, occupational therapy, and orthopedic interventions may be recommended to promote self care ability and independence. For example, exercises and retraining may increase muscle strength and control. Appliances such as wheelchairs, braces, and splints. may provide mobility or help to support an extremity so that it can be used.

Control of symptoms:
Safety is an important consideration for people with neuropathy. Lack of muscle control may increase the risk of falls or other injuries. Also, decreased sensation may increase the risk of falls and injuries because the person is unable to perceive a potential source of harm.

Safety measures for people with difficulty in movement may include railings, various appliances, removal of obstacles (such as loose rugs that may slip on the floor), and other measures as appropriate.

Safety measures for people experiencing difficulty with sensation include awareness of the lack of sensation and compensation through other measures. Specific measures may include the use of adequate lighting (including lights left on at night), testing of water temperature before bathing or immersing parts of the body in water, use of protective shoes (such as those with no open toes and with no high heels), and similar measures. Shoes should be checked inside frequently for grit or rough spots that may injure the feet.

People with decreased sensation should check their feet (or other affected area) frequently for bruises, open skin areas, or other injury, which may go unnoticed and become severely infected.

People with neuropathy are prone to new nerve injury at pressure points (such as knees and elbows). They should avoid prolonged pressure on these areas from leaning on the elbows, crossing the knees, or being in similar positions.

Over-the-counter analgesics or prescription analgesics may be needed to control pain ( neuralgia ). Various other medications may be used to reduce the stabbing pains that some people experience, including anticonvulsants (phenytoin, carbamazepine) or tricyclic antidepressants. Whenever possible, their use should be avoided or minimized to reduce the risk of medication side effects.

Positioning, use of bed frames to keep bedclothes off a tender body part, or other measures may be helpful to control pain.

Prognosis:
If the cause of the sensorimotor polyneuropathy can be identified and successfully treated, and if the damage is limited to the axon or myelin sheath (leaving the cell body intact), there is a possibility of full recovery from peripheral neuropathy . The extent of the disability varies, from no disability to partial or complete loss of movement , function, or sensation. Nerve pain may be quite uncomfortable and persist for a prolonged period of time. In some instances, the disorder may cause severe, life-threatening symptoms.

Complications:



Call Your Healthcare Provider:
Call your health care provider if loss of movement or sensation of a part of the body occurs. Early diagnosis and treatment increase the chance of controlling the symptoms.