The symptoms depend on which type of nerve is affected. The three main types of nerves are:

• Those that carry sensations (sensory)
• Those that control muscles (motor)
• Those that carry information to organs and glands (autonomic)

Neuropathy can affect any one or a combination of all three types of nerves. Symptoms also depend on whether the condition affects the whole body or just one nerve (as from an injury).

Longer nerves are more easily injured than shorter ones, so it is common for you to have worst symptoms in the legs and feet than in the hands and arms.

SENSATION CHANGES

Damage to sensory fibers results in changes in sensation, burning sensations, nerve pain, tingling or numbness, or an inability to determine joint position, which causes incoordination.

For many neuropathies, sensation changes often begin in the feet and progress toward the center of the body with involvement of other areas as the condition worsens. Diabetes is a common cause for sensory neuropathy.

MOVEMENT DIFFICULTIES

Damage to the motor fibers interferes with muscle control and can cause weakness, loss of muscle bulk, and loss of dexterity. Sometimes, cramps are a sign of motor nerve involvement.

Other muscle-related symptoms include:

• Difficulty breathing or swallowing
• Difficulty or inability to move a part of the body (paralysis)
• Falling (from legs buckling or tripping over toes)
• Lack of dexterity (such as being unable to button a shirt)
• Lack of muscle control
• Loss of muscle tissue (muscle atrophy)
• Muscle twitching or cramping

AUTONOMIC SYMPTOMS

The autonomic nerves control involuntary or semi-voluntary functions, such as control of internal organs and blood pressure. Damage to autonomic nerves can cause:

• Abdominal bloating
• Blurred vision
• Constipation
• Decreased ability to sweat
• Diarrhea
• Difficulty beginning to urinate (urinary hesitancy)
• Dizziness that occurs when standing up or fainting associated with a fall in blood pressure
• Feeling full after eating a small amount (early satiety)
• Feeling of incomplete bladder emptying
• Heat intolerance with exertion
• Male impotence
• Nausea or vomiting after meals
• Unintentional weight loss (more than 5% of body weight)
• Urinary incontinence

A detailed history will be needed to determine the cause of the neuropathy. A neurological exam may reveal problems with movement, sensation, or organ function. Changes in reflexes and muscle bulk may also be present.

Blood tests may be done to screen for medical conditions such as diabetes and vitamin deficiencies.

Tests that reveal neuropathy may include:

• EMG (a recording of electrical activity in muscles)
• Nerve conduction tests
• Nerve biopsy

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