Mononeuritis multiplex

Answer 1

Definition

Mononeuritis multiplex is a brain/nervous system (neurological) disorder that involves damage to at least two separate nerve areas.

Alternative Names

Mononeuropathy multiplex; Multifocal neuropathy

Causes, incidence, and risk factors

Mononeuritis multiplex is a form of damage to nerves outside the brain and spinal cord (peripheral neuropathy). It is a group of symptoms, not a disease. A part of the nerve cell called the axon is destroyed, which interferes with nerve signaling.

The cause of mononeuritis multiplex affects nerves in many areas. As the disorder gets worse, the damage may become more widespread and affect more nerves. Common causes include:

• A lack of oxygen from decreased blood flow
• Swelling and irritation (inflammation) of blood vessels

No cause is found in about a third of cases.

Common causes of mononeuritis multiplex include:

• Blood vessel diseases such as polyarteritis nodosa
• Connective tissue diseases such as rheumatoid arthritis or systemic lupus erythematosus
• Diabetes mellitus

Connective tissue disease is the most common cause of mononeuritis multiplex in children.

Less common causes include:

• Amyloidosis
• Disorders of the blood (such as hypereosinophilia and cryoglobulinemia)
• Infections such as Lyme disease
• Leprosy
• Sarcoidosis
• Sjogren syndrome
• Wegener's granulomatosis

Symptoms

• Abnormal sensation
• Burning pain
• Difficulty moving a part of the body (paralysis)
• Inability to move a part of the body
• Lack of control over movement in a part of the body
• Lack of or decreased sensation in any part of the body
• Numbness and tingling

Specific symptoms depend on the nerve involved.

Signs and tests

A detailed history is needed to determine the possible cause of the disorder. Examination and neuromuscular testing may show a loss of feeling and movement due to problems with specific nerves. Reflexes may be abnormal.

To diagnose mononeuritis multiplex usually requires problems with two or more unrelated nerve areas. Common findings may include the following:

• Axillary nerve dysfunction
• Common peroneal nerve dysfunction
• Distal median nerve dysfunction
• Femoral nerve dysfunction
• Radial nerve dysfunction
• Sciatic nerve dysfunction
• Ulnar nerve dysfunction

Tests that may be done include:

• EMG
• Nerve biopsy
• Nerve conduction velocity

Other possible tests include:

• Antinuclear antibody panel
• Blood tests
• C-reactive protein
• Imaging tests
• Lyme disease antibody
• Rheumatoid factor
• X-rays

Treatment

The goals of treatment are to:

• Treat the cause, if possible
• Provide supportive care to maximize independence
• Control symptoms (this may include controlling blood sugar levels for diabetics, nutritional supplementation, or medical treatment of conditions)

To improve independence, treatments may include:

• Occupational therapy
• Orthopedic help (for example, appliances such as wheelchairs, braces, and splints)
• Physical therapy (for example, exercises and retraining to increase muscle strength)
• Vocational therapy

Safety is an important consideration for people with sensation or movement difficulties. Lack of muscle control and decreased sensation may increase the risk of falls or injuries. Safety measures for people with movement difficulty may include:

• Adequate lighting (including leaving lights on at night)
• Railings
• Removing obstacles (such as loose rugs that may slip on the floor)
• Testing water temperature before bathing
• Wearing protective shoes (no open toes or high heels)

Check shoes often for grit or rough spots that may injure the feet.

People with decreased sensation should check their feet (or other affected area) often for bruises, open skin areas, or other injuries that may go unnoticed. These injuries may become severely infected because the pain nerves of the area are not signalling the injury.

People with mononeuropathy multiplex are prone to new nerve injuries at pressure points such as knees and elbows. They should avoid putting pressure on these areas, for example by not leaning on the elbows, crossing the knees, or holding similar positions.

Over-the-counter analgesics or prescription pain medications may be needed to control pain (neuralgia). Other medications, including anticonvulsants (gabapentin, phenytoin, carbamazepine) or tricyclic antidepressants, may be used to reduce the stabbing pains that some people experience. Whenever possible, avoid or minimize the use of medications to reduce the risk of side effects.

Positioning (the use of frames to keep bedclothes off of a tender body part) and other measures may help control pain. Autonomic symptoms can be difficult to treat or respond poorly to treatment.

Expectations (prognosis)

If the cause can be found and successfully treated, and if damage is limited, a full recovery is possible. The amount of disability can range from no disability, to partial or complete loss of movement, function, or sensation.

Nerve pain may be quite uncomfortable and can last for a long time. If this occurs, see a pain specialist to ensure that all pain treatment options are available to you.

Complications

• Decreased self-esteem
• Deformity, loss of tissue mass
• Disturbances of organ functions
• Recurrent or unnoticed injury to any part of the body
• Relationship problems due to impotence

Calling your health care provider

Call your health care provider if you notice signs of mononeuritis multiplex.

Prevention

Prevention techniques vary depending on the specific disorder. Proper diet and use of medication for Diabetes may help prevent neuropathy from developing.

Answer 2

Definition

Mononeuritis multiplex is a nervous system disorder that involves damage to at least two separate nerve areas.

Alternative Names

Mononeuropathy multiplex; Multifocal neuropathy; Peripheral neuropathy - mononeuritis multiplex

Causes, incidence, and risk factors

Mononeuritis multiplex is a form of damage to one or more peripheral nerves -- the nerves outside the brain and spinal cord. It is a group of symptoms (syndrome), not a disease.

However, certain diseases can cause the injury or nerve damage that leads to the symptoms of mononeuritis multiplex. Common conditions include:

• Blood vessel diseases such as polyarteritis nodosa
• Connective tissue diseases such as rheumatoid arthritis or systemic lupus erythematosus (the most common cause in children)
• Diabetes mellitus

Less common causes include:

• Amyloidosis
• Blood disorders (such as hypereosinophilia and cryoglobulinemia)
• Infections such as Lyme disease
• Leprosy
• Sarcoidosis
• Sjogren syndrome
• Wegener's granulomatosis

Symptoms

Symptoms will depend on the specific nerves involved, and may include:

• Loss of bladder or bowel control
• Loss of sensation in one or more areas of the body
• Paralysis in one or more areas of the body
• Tingling, burning, pain, or other abnormal sensations in one or more areas of the body
• Weakness in one or more areas of the body

Signs and tests

A detailed history is needed to determine the possible cause of the disorder. Examination and neuromuscular testing may show a loss of feeling and movement due to problems with specific nerves. Reflexes may be abnormal.

To diagnose mononeuritis multiplex, there usually needs to be problems with two or more unrelated nerve areas. Common nerves affected are the:

• Axillary nervein either arm and shoulder
• Common peroneal nerve in the lower leg
• Distal median nerve to the hand
• Femoral nervein the thigh
• Radial nerve in the arm
• Sciatic nervein the back of the leg
• Ulnar nerve in the arm

Tests may include:

• Electromyogram(EMG, a recording of electrical activity in the muscles)
• Nerve biopsy to examine the nerve under a microscope
• Nerve conduction tests to measure how fast nerve impulses move along the nerve

Other tests may include:

• Antinuclear antibody panel (ANA)
• Blood chemistry tests
• C-reactive protein
• Imaging scans
• Pregnancy test
• Rheumatoid factor
• Sedimentation rate
• Thyroid tests
• X-rays

Treatment

The goals of treatment are to:

• Treat the illness that is causing the problem, if possible
• Provide supportive care to maximize independence
• Control symptoms (this may include controlling blood sugar levels for diabetics, nutritional supplementation, or medically treating conditions)

To improve independence, treatments may include:

• Occupational therapy
• Orthopedic help (for example, appliances such as wheelchairs, braces, and splints)
• Physical therapy (for example, exercises and retraining to increase muscle strength)
• Vocational therapy

Safety is an important consideration for people with sensation or movement difficulties. Lack of muscle control and decreased sensation may increase the risk of falls or injuries. Safety measures for people with movement difficulty include:

• Adequate lighting (including leaving lights on at night)
• Railings
• Removing obstacles (such as loose rugs that may slip on the floor)
• Testing water temperature before bathing
• Wearing protective shoes (no open toes or high heels)

Check shoes often for grit or rough spots that may injure the feet.

People with decreased sensation should check their feet (or other affected area) often for bruises, open skin areas, or other injuries that may go unnoticed. These injuries may become severely infected because the pain nerves of the area are not signaling the injury.

People with mononeuropathy multiplex are prone to new nerve injuries at pressure points such as knees and elbows. They should avoid putting pressure on these areas, for example by not leaning on the elbows, crossing the knees, or holding similar positions.

Medications that may help include:

• Over-the-counter pain medicines (ibuprofen or acetaminophen) or prescription pain medications may be needed to control pain (neuralgia).
• Anticonvulsants (gabapentin, phenytoin, carbamazepine, or pregabalin) or antidepressants (amitriptyline, nortriptyline, or duloxetine), may be used to reduce stabbing pains.

Whenever possible, avoid or minimize the use of medications to reduce the risk of side effects.

Positioning (the use of frames to keep bedclothes off of a tender body part) and other measures may help control pain. Autonomic symptoms can be difficult to treat or respond poorly to treatment.

Expectations (prognosis)

If the cause can be found and successfully treated, and if damage is limited, a full recovery is possible. The amount of disability can range from no disability, to partial or complete loss of movement, function, or sensation.

Nerve pain may be quite uncomfortable and can last for a long time. If this occurs, see a pain specialist to ensure that all pain treatment options are available to you.

Complications

• Deformity, loss of tissue or muscle mass
• Disturbances of organ functions
• Medication side effects
• Repeated or unnoticed injury to the affected area due to lack of sensation
• Relationship problems due to impotence

Calling your health care provider

Call your health care provider if you notice signs of mononeuritis multiplex.

Prevention

Preventive measures vary depending on the specific disorder. Eating a proper diet and taking medication for diabetes may help prevent mononeuritis multiplex from developing.

References

Shy ME. Peripheral neuropathies. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 446.

Reviewed By

Review Date: 09/13/2010

Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.