Fatty acid oxidation disorders (FAODs) are a group of rare, inherited metabolic disorders. These disorders arise from defects in the enzymes and proteins responsible for transporting and metabolizing fatty acids within the mitochondria. These defects prevent the body from effectively converting fats into energy, especially during periods of fasting or illness.
Understanding FAODs
- Genetic Basis: FAODs are autosomal recessive, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the disorder.
- Metabolic Impact: Fatty acids are a major energy source, particularly when glucose (sugar) levels are low. When the fatty acid oxidation process is impaired, the body cannot efficiently break down fats for energy. This leads to a reliance on glucose, which can become depleted, resulting in hypoglycemia (low blood sugar). Additionally, unmetabolized fatty acids and their byproducts can accumulate, potentially causing damage to various organs.
- Variety of Disorders: FAODs encompass several specific conditions, each resulting from a deficiency in a particular enzyme or protein involved in fatty acid metabolism. Examples include:
- Medium-chain acyl-CoA dehydrogenase deficiency (MCADD)
- Very long-chain acyl-CoA dehydrogenase deficiency (VLCADD)
- Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD)
- Carnitine palmitoyltransferase I or II deficiency (CPT I or CPT II)
- Carnitine-acylcarnitine translocase deficiency (CACT)
- Symptoms and Diagnosis: Symptoms vary depending on the specific FAOD and can range from mild to severe. They often include:
- Hypoglycemia (low blood sugar)
- Lethargy
- Muscle weakness
- Liver problems
- Heart problems
- Seizures
- Rhabdomyolysis (muscle breakdown)
FAODs are typically diagnosed through newborn screening, blood tests (acylcarnitine profile), urine tests, and genetic testing.
- Treatment and Management: Treatment focuses on preventing metabolic crises by:
- Avoiding prolonged fasting
- Following a special diet low in long-chain fats and high in carbohydrates
- Frequent feedings, especially during infancy and childhood
- Carnitine supplementation (in some cases)
- Emergency protocols for managing metabolic crises
In summary, fatty acid oxidation disorders are a group of genetic conditions affecting the body's ability to process fats for energy, leading to potential health complications that require careful dietary management and monitoring.
