Carnitine palmitoyltransferase IA (CPT1A) deficiency hinders the body’s ability to convert long-chain fatty acids into energy for essential bodily functions.
CPT1A deficiency symptoms typically manifest in severe episodes, often triggered by extended periods of fasting, fever, or gastrointestinal illnesses. The onset of symptoms usually occurs during infancy and is characterized by hypoglycemia (low blood sugar) and reduced levels of ketones, crucial for energy production from fat breakdown. This combination of symptoms is termed hypoketotic hypoglycemia and can lead to unconsciousness or seizures if left untreated. Additional manifestations of CPT1A deficiency encompass hepatomegaly (enlarged liver), muscle weakness, and potential damage to the liver, heart, and brain due to excessive accumulation of fatty acids. Without intervention, these symptoms can be life-threatening. Importantly, some individuals with CPT1A deficiency may not exhibit symptoms until later in life, despite the underlying genetic mutation.
CPT1A deficiency is caused by pathogenic (disease-causing) variants in the CPT1A gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. For example, individuals of Ashkenazi Jewish descent have a 1 in 491 chance to be a carrier.
Carriers do not typically show symptoms of the disease. However, there maybe an increased risk of serious pregnancy complications, particularly in the third trimester, in women carrying a fetus affected with a fatty-acid oxidation defect. A woman whose pregnancy may be affected by a fatty-acid oxidation defect, such as CPT1A deficiency, should speak with her physician for recommendations and may benefit from consultation with a high-risk physician.
Other names for this condition are CPT 1A deficiency, CPT deficiency, hepatic, type I, and liver form of carnitine palmitoyltransferase deficiency
Resources:
National Organization of Rare Disorders
Revised September 2023
