Isovaleric Acidemia (IVA) is a disorder caused by a problem with an enzyme that breaks down a specific amino acid called leucine. This leads to a buildup of harmful substances in the blood, which can damage the brain and nervous system.
There are three types of IVA: neonatal, childhood-onset, and mild.
Neonatal IVA causes babies to have trouble feeding, high acidity in the blood and urine, and difficulty maintaining body temperature. If untreated, it can lead to severe issues like brain bleeding, seizures, and even death. Childhood IVA typically appear around 12 months of age, triggered by stressors like illness or fasting. Without stress, there might be no symptoms. However, children with this form could face learning difficulties, slow growth, and weak muscles. The mild form of IVA may cause mild developmental delays, but not the severe symptoms seen in the neonatal or childhood forms. People with IVA need a specific diet low in leucine and rich in proteins. Infants might use a leucine-free formula. Close monitoring by a doctor, especially during illnesses, is crucial. Prompt treatment for symptoms like vomiting and diarrhea is necessary. With early diagnosis and proper care, individuals with IVA can lead healthier lives with improved growth and development.
IVA is caused by pathogenic (disease-causing) variants in the IVD 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.
Other names for this condition are isovaleric acid-CoA dehydrogenase deficiency, isovaleryl-CoA dehydrogenase deficiency, and IVD deficiency.
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Revised October 2023
