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Primary Carnitine Deficiency

What is Primary Carnitine Deficiency?

Primary carnitine deficiency is a condition in which the body cannot properly process fats into energy. It is caused by a defect in the protein that transports carnitine, a natural substance derived from an amino acid. The condition is typically treatable by the daily use of L-carnitine supplements. However without early detection and treatment, the condition can cause permanent brain damage and may even prove fatal.

If left untreated, primary carnitine deficiency causes a weakening of the heart muscles, leading to a diminished ability to pump blood around the body (cardiomyopathy). Both the heart and liver may become enlarged. It also causes a weakness in skeletal muscles and dangerously low blood sugar (hypoglycemia) that can lead to brain damage. While this brain damage can cause irreversible learning problems or even mental retardation, the remaining symptoms tend to disappear once the person begins taking L-carnitine supplements.

Without supplements, a person with primary carnitine deficiency is particularly vulnerable to "metabolic crisis"-sleepiness, irritability, fever, nausea, vomiting, low blood sugar-when they go long periods without eating or are ill. If the crises are not treated, the child may experience seizures, swelling of the brain, and other life-threatening symptoms.

How common is Primary Carnitine Deficiency?

Primary carnitine deficiency affects approximately 1 in 100,000 newborns and is known to be more common-1 in 40,000-in Japan.

How is Primary Carnitine Deficiency treated?

People with primary carnitine deficiency will need to take supplements of L-carnitine for their entire lives. If these children have begun to experience heart problems or muscle weakness, they can typically reverse those symptoms by taking L-carnitine. A physician may also recommend that people with primary carnitine deficiency eat more frequently, even if they don't feel hungry. This is particularly important when they are young and/or sick.

What is the prognosis for a person with Primary Carnitine Deficiency?

With regular treatment begun at birth, the prognosis for a person with primary carnitine deficiency is very good. They can typically live normal lives. If treatment is not begun soon enough, these children can experience permanent brain damage, leading to learning difficulties or even mental retardation. Without any treatment, the disease causes numerous serious health problems and would likely be fatal.


Fatty Oxidation Disorders Family Support Group

An all volunteer 501c3 non-profit dedicated to providing support, information and international networking for families affected by a Fatty Oxidation Disorder, as well as for professionals working with FOD families.

Director, Deb Lee Gould, MEd
PO Box 54
Okemos, MI 48805-0054
Phone: (517) 381-1940 (8am-8pm EST)
Skype: fodgroup

Genetics Home Reference

Explanations of an extensive number of genetic diseases written by the U.S. government's National Institutes of Health.