Dr C P Ravikumar

Carnitine
Carnitine ( also called Carnitor or Vitamin B13)  is derived from amino acids and is present in all the cells of the human body, concentrated in skeletal and cardiac muscles. The body is able to generate its own carnitine, to give an active molecule, L-carnitine , while acetyl-L-carnitine, and propionyl-L-carnitine are available as dietary supplements, as they are generally well tolerated and safe as therapeutic agents.

Health Benefits of Carnitine
  1. It helps with the metabolism of fatty acid chains inside cells to produce energy
  2. Transports toxic by-products of energy production outside the cells
  3. Helps to improve nerve conduction and neuropathic pain
  4. Improves immunity
  5. Used as a nutritional supplement in cardiovascular disease
  6. Studies have demonstrated its use in Alzheimer’s, where it helps to improve cognitive functions and decreases the effects of aging
  7. Used by athletes to improve performance, or as an aid for weight loss
  8. Nutritional supplement to reduce the risk of cardiovascular disease.

Sources of Carnitine
  1. Red meat
  2. Milk and dairy products
  3. Poultry
  4. Wheat
  5. Vegetables

Deficiency of Carnitine occurs when less than 10% of the nutrient is available to the cells to use. The causes contributing to this are : 
1. Primary carnitine deficiency is due to genetic mutations that cause disruptions in the absorption and assimilation of carnitine in the body, which manifests at the age of 5 years with symptoms of cardiomyopathy, skeletal muscle weakness and hypoglycaemia. It is also known as a carnitine uptake defect.
2.Secondary Carnitine Deficiency, may result due to
  • Decreased nutritional intake, malnutrition or digestive diseases causing malabsorption of  nutrients in the gut.
  • Liver diseases or chronic renal function impairments , dispelling increased levels of carnitine from the body, without assimilation.
  • Endocrine disorders like diabetes
  • Sepsis
  • Cardiomyopathy
  • Aging
  • Patients on anti-epileptic medications,like carbamazepine, phenytoin and phenobarbital, show decreased levels of carnitine. Patients on valproate for epilepsy may also show signs of hyperammonaemia. This is usually asymptomatic but may lead to encephalopathy, which displays symptoms of neurological slowing like decreased appetite, lethargy, rapid or heavy, breathing, irritability as well as electroencephalography changes. Although these changes are reversible, if left untreated, it may progress to coma. Long term valproic acid therapy can deplete carnitine stores, which in turn is associated with increased ammonia levels. Therefore, Levocarnitine supplements are known to help in this condition.

Diagnosis of Carnitine deficiency :
  • Blood tests :
    1. to determine the levels of carnitine in the blood.
    2. creatine kinase to show muscle damage.
    3. Elevated liver enzymes to indicate liver damage or hepatotoxicity
    4. Serum ammonia levels to determine signs of toxicity
  • Urine test: for ketones
  • Genetic test : in order to confirm primary carnitine deficiency.
  • Heart tests : Tests such as echocardiography can show if the heart is affected, looking for signs of cardiomyopathy

Management of Carnitine deficiency
Treatment of patients suffering from carnitine deficiency, with supplements may decrease the symptoms of primary carnitine deficiency, and also helps to prevent hyperammonaemia, in patients on prolonged treatment of seizures on anti-epileptic medications like valproic acid.

Disclaimer: The above information is for awareness and education purposes only and cannot be used for diagnosis or treatment of any condition. Please consult with a physician for any concerns or questions

Dr C P Ravikumar

Dr C P Ravikumar

CONSULTANT – PEDIATRIC NEUROLOGY
Aster CMI Hospital, Bangalore