Metabolic neuropathies

  • Definition
    • Metabolic neuropathies are nerve disorders that occur with diseases that disrupt the chemical processes in the body

  • Alternative Names
    • Neuropathy - metabolic

  • Causes
    • Nerve damage can be caused by many different things. Metabolic neuropathy may be caused by:

      • A problem with the body's ability to use energy, often due to a lack of enough nutrients (nutritional deficiency)
      • Dangerous substances (toxins) that build up in the body

      Diabetes is one of the most common causes of metabolic neuropathies. People who are at the highest risk for nerve damage (diabetic neuropathy) from diabetes include those who have:

      • Damage to the kidneys or eyes
      • Poorly controlled blood sugar

      Other common causes of metabolic neuropathies include:

      Some metabolic disorders are passed down through families (inherited), while others develop due to various diseases.

  • Symptoms
    • These symptoms occur because nerves cannot send proper signals to and from your brain:

      • Difficulty feeling in any area of the body
      • Difficulty using the arms or hands
      • Difficulty using the legs or feet
      • Difficulty walking
      • Pain, burning feeling, pins and needles feeling, or shooting pains in any area of the body (nerve pain)
      • Weakness in the face, arms, legs, or other areas of the body

      These symptoms often start in the toes and feet and move up the legs, eventually affecting the hands and arms.

  • Exams and Tests
    • Your health care provider will examine you and ask about your symptoms. During the exam, your provider may find that you have:

      • Decreased feeling (may affect touch, pain, vibration, or position sensation)
      • Reduced reflexes (most common in the ankle)
      • Muscles becoming smaller (atrophy)
      • Muscle twitches (fasciculations)
      • Muscle weakness
      • Loss of movement (paralysis)

      Tests that may be ordered include:

      • Blood tests
      • Electrical test of the muscles (EMG)
      • Electrical test of nerve conduction
  • Treatment
    • For most metabolic neuropathies, the best treatment is to correct the metabolic problem.

      Vitamin deficiencies are treated with diet or with vitamins by mouth or by injection. Abnormal blood sugar level or thyroid function may need medicines to correct the problem. For alcoholic neuropathy, the best treatment is to stop drinking.

      In some cases, pain is treated with medicines that reduce abnormal pain signals from the nerves.  In some cases, lotions, creams, or medicated patches can provide relief.

      Weakness is often treated with physical therapy. You may need to learn how to use a cane or walker if your balance is affected. You may need special ankle braces to help you walk better.

  • Support Groups
  • Outlook (Prognosis)
    • The outlook mainly depends on the cause of the disorder. In some cases, the problem can easily be treated. In other cases, the metabolic problem cannot be controlled, and nerves may continue to become damaged.

  • Possible Complications
    • Complications that may result include:

      • Deformity
      • Injury to feet
      • Numbness or weakness
      • Pain
      • Trouble walking
  • Prevention
    • Maintaining a healthy lifestyle can reduce the risk for neuropathy.

      • Avoid excess alcohol use.
      • Eat a balanced diet.
      • Visit your provider regularly to find metabolic disorders before neuropathy develops.

      If you have neuropathy in your feet, a foot doctor (podiatrist) can teach you how to inspect your feet for signs of injury and infection. Proper fitting shoes can lessen the chance of skin breakdown in sensitive areas of the feet.

  • References
    • Dhawan PS, Goodman BP. Neurologic manifestations of nutritional disorders. In: Aminoff MJ, Josephson SA, eds. Aminoff's Neurology and General Medicine. 5th ed. Philadelphia, PA: Elsevier; 2014:chap 15.

      Patterson MC, Percy AK. Peripheral neuropathy in inherited metabolic disease. In: Darras BT, Jones HR, Ryan MM, De Vivo DC, eds. Neuromuscular Disorders of Infancy, Childhood, and Adolescence. 2nd ed. Philadelphia, PA: Elsevier; 2015:chap 19.

      Ralph JW, Aminoff MJ. Neuromuscular complications of general medical disorders. In: Aminoff MJ, Josephson SA, eds. Aminoff's Neurology and General Medicine. 5th ed. Philadelphia, PA: Elsevier; 2014:chap 59.

      Shy ME. Peripheral neuropathies. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 420.