Metabolic neuropathies are nerve disorders that occur with diseases that disrupt the chemical processes in the body
Neuropathy - metabolic
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:
- Alcohol use disorder (alcoholic neuropathy)
- Low blood sugar (hypoglycemia)
- Kidney failure
- Inherited conditions, such as porphyria
- Severe infection throughout the body (sepsis)
- Thyroid disease
- Vitamin deficiencies (including vitamins B12, B6, E, and B1)
Some metabolic disorders are passed down through families (inherited), while others develop due to various diseases.
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, a 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
- Dysautonomia, which affects the autonomic (involuntary) nervous system, resulting in symptoms such as rapid heart rate, exercise intolerance, low blood pressure when standing, abnormal sweat patterns, stomach problems, abnormal functioning of the pupils of the eye, and poor erection
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.
Tests that may be ordered include:
- Blood tests
- Electrical test of the muscles (electromyography or EMG)
- Electrical test of nerve conduction
- Nerve tissue biopsy
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.
These groups can provide more information on neuropathy:
- Neuropathy Action Foundation -- www.neuropathyaction.org
- The Foundation for Peripherial Neuropathy -- www.foundationforpn.org
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.
Complications that may result include:
- Injury to feet
- Numbness or weakness
- Trouble walking and falls
Maintaining a healthy lifestyle can reduce the risk for neuropathy.
- Avoid excess alcohol use.
- Eat a balanced diet.
- Quit smoking.
- 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.
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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. Waltham, MA: Elsevier Academic Press; 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. Waltham, MA: Elsevier Academic Press; 2014:chap 59.
Smith G, Shy ME. Peripheral neuropathies. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 392.