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LCHAD deficiency

Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency

(often shortened to LCHAD deficiency)
Reviewed July 2009

What is LCHAD deficiency?

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting).

Signs and symptoms of LCHAD deficiency typically appear during infancy or early childhood and can include feeding difficulties, lack of energy (lethargy), low blood sugar (hypoglycemia), weak muscle tone (hypotonia), liver problems, and abnormalities in the light-sensitive tissue at the back of the eye (retina). Later in childhood, people with this condition may experience muscle pain, breakdown of muscle tissue, and a loss of sensation in their arms and legs (peripheral neuropathy). Individuals with LCHAD deficiency are also at risk for serious heart problems, breathing difficulties, coma, and sudden death.

Problems related to LCHAD deficiency can be triggered by periods of fasting or by illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections.

How common is LCHAD deficiency?

The incidence of LCHAD deficiency is unknown. One estimate, based on a Finnish population, indicates that 1 in 62,000 pregnancies is affected by this disorder. In the United States, the incidence is probably much lower.

What genes are related to LCHAD deficiency?

Mutations in the HADHA gene cause LCHAD deficiency. The HADHA gene provides instructions for making part of an enzyme complex called mitochondrial trifunctional protein. This enzyme complex functions in mitochondria, the energy-producing centers within cells. As the name suggests, mitochondrial trifunctional protein contains three enzymes that each perform a different function. This enzyme complex is required to break down (metabolize) a group of fats called long-chain fatty acids. Long-chain fatty acids are found in foods such as milk and certain oils. These fatty acids are stored in the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues.

Mutations in the HADHA gene that cause LCHAD deficiency disrupt one of the functions of this enzyme complex. These mutations prevent the normal processing of long-chain fatty acids from food and body fat. As a result, these fatty acids are not converted to energy, which can lead to some features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may also build up and damage the liver, heart, muscles, and retina. This abnormal buildup causes the other signs and symptoms of LCHAD deficiency.

Read more about the HADHA gene.

How do people inherit LCHAD deficiency?


Where can I find information about diagnosis or management of LCHAD deficiency?

These resources address the diagnosis or management of LCHAD deficiency and may include treatment providers.

You might also find information on the diagnosis or management of LCHAD deficiency in Educational resources and Patient support.



Where can I find additional information about LCHAD deficiency?

You may find the following resources about LCHAD deficiency helpful. These materials are written for the general public.


What other names do people use for LCHAD deficiency?

  • 3-hydroxyacyl-CoA dehydrogenase, long chain, deficiency
  • long-chain 3-hydroxy acyl CoA dehydrogenase deficiency
  • long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency
  • long-chain 3-OH acyl-CoA dehydrogenase deficiency
  • trifunctional protein deficiency, type 1


What if I still have specific questions about LCHAD deficiency?

Where can I find general information about genetic conditions?

What glossary definitions help with understanding LCHAD deficiency?

References (10 links)



Reviewed: July 2009
Published: February 1, 2016