Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency
Classification and external resources
Specialty
ICD-9-CM	277.85
OMIM	600890
eMedicine	ped/1284
Patient UK	Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency, often shortened to LCHAD deficiency, is a rare autosomal recessive fatty acid oxidation disorder that prevents the body from converting certain fats into energy. This can become life-threatening, particularly during periods of fasting.

Schematic demonstrating mitochondrial fatty acid beta-oxidation and effects of LCHAD deficiency

Genetics

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency has an autosomal recessive pattern of inheritance.

Mutations in the HADHA gene lead to inadequate levels of an enzyme called long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase, which is part of a protein complex known as mitochondrial trifunctional protein. Long-chain fatty acids from food and body fat cannot be metabolized and processed without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, retina, and muscles, causing more serious complications.

Symptoms

Typically, initial signs and symptoms of this disorder occur during infancy or early childhood and can include feeding difficulties, lethargy, hypoglycemia, hypotonia, liver problems, and abnormalities in the retina. Muscle pain, a breakdown of muscle tissue, and abnormalities in the nervous system that affect arms and legs (peripheral neuropathy) may occur later in childhood. There is also a risk for complications such as life-threatening heart and breathing problems, coma, and sudden unexpected death. Episodes of LCHAD deficiency can be triggered by periods of fasting or by illnesses such as viral infections.

See also

• Medium chain acyl dehydrogenase deficiency

External links

• Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency at NLM Genetics Home Reference
• Newbornscreening.info