Definition of Mononeuritis multiplex:

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

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