Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.

Diseases

Genetic and Rare Diseases Information Center (GARD)

Print friendly version

Isovaleric acidemia


Other Names for this Disease

  • Isovaleric acid CoA dehydrogenase deficiency
  • Isovaleryl CoA carboxylase deficiency
  • IVA
  • IVD deficiency
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Your Question

My baby died 13 days after birth. The doctors performed some blood tests which indicated that the baby had isovaleric acidemia. Additional testing, only available in the UK was recommended. Unfortunately, the lab would not accept blood without urine. What are the chances that my future child(ren) will also have this condition?

Our Answer

We have identified the following information that we hope you find helpful. If you still have questions, please contact us.

What is isovaleric acidemia?

Isovaleric acidemia (IVA) is a type of organic acid disorder in which affected individuals have problems breaking down an amino acid called leucine from the food they eat.[1][2] Signs and symptoms may range from very mild to life-threatening. In severe cases, symptoms begin within a few days of birth and include poor feeding, vomiting, seizures, and lack of energy (lethargy); these may progress to more serious medical problems including seizures, coma, and possibly death. In other cases, signs and symptoms appear during childhood and may come and go over time. A characteristic sign of IVA is a distinctive odor of sweaty feet during acute illness. Other features may include failure to thrive or delayed development. IVA is caused by mutations in the IVD gene and is inherited in an autosomal recessive manner.[1] Treatment involves moderate restriction of proteins in the diet and oral administration of glycine and L-carnitine which helps to rid the body of excess isovaleric acid.[2][3][4]
Last updated: 5/16/2014

What are the signs and symptoms of isovaleric acidemia?

Health problems related to isovaleric acidemia range from very mild to life-threatening. In severe cases, the features of isovaleric acidemia become apparent within a few days after birth. The initial symptoms include poor feeding, vomiting, seizures, and lack of energy (lethargy). These symptoms sometimes progress to more serious medical problems, including seizures, coma, and possibly death. A characteristic sign of isovaleric acidemia is a distinctive odor of sweaty feet during acute illness. This odor is caused by the buildup of a compound called isovaleric acid in affected individuals.[1][4]

In other cases, the signs and symptoms of isovaleric acidemia appear during childhood and may come and go over time. Children with this condition may fail to gain weight and grow at the expected rate (failure to thrive) and often have delayed development. In these children, episodes of more serious health problems can be triggered by prolonged periods without food (fasting), infections, or eating an increased amount of protein-rich foods.[1]

Some people with gene mutations that cause isovaleric acidemia are asymptomatic, which means they never experience any signs or symptoms of the condition.[1]
Last updated: 5/16/2014

What causes isovaleric acidemia?

Isovaleric acidemia is caused by mutations in the IVD gene. The IVD gene provides instructions for making an enzyme that plays an essential role in breaking down proteins from the diet. Specifically, this enzyme helps process the amino acid leucine, which is part of many proteins. If a mutation in the IVD gene reduces or eliminates the activity of this enzyme, the body is unable to break down leucine properly. As a result, an organic acid called isovaleric acid and related compounds build up to harmful levels in the body. This buildup damages the brain and nervous system, causing serious health problems.[1]
Last updated: 5/16/2014

How is isovaleric acidemia inherited?

Isovaleric acidemia is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.[1]
Last updated: 5/16/2014

Since I have already had a child with isovaleric acidemia, what are the chances that my future child(ren) will be affected by this condition?

At conception, each sibling of an individual with isovaleric acidemia has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier.[5]   Once an at-risk sibling is known to be unaffected, the risk of his/her being a carrier is 2/3. Carriers typically do not show signs and symptoms of the condition.[5] 

We encourage you to consult with a genetics professional who can discuss with you at length your risk to have another child with isovaleric acidemia. Information about how to find a genetics professional can be found through the Services tab.
Last updated: 6/8/2011

References
Other Names for this Disease
  • Isovaleric acid CoA dehydrogenase deficiency
  • Isovaleryl CoA carboxylase deficiency
  • IVA
  • IVD deficiency
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.