What is valinemia?
Valinemia is a very rare metabolic disorder. It is characterized by elevated levels of the amino acid valine in the blood and urine caused by a deficiency of the enzyme valine transaminase. This enzyme is needed in the breakdown (metabolism) of valine. Infants with valinemia usually have a lack of appetite, vomit frequently, and fail to thrive. Low muscle tone (hypotonia) and hyperactivity also occur.
The breakdown of valine involves at least seven stages and a deficiency of the appropriate enzyme at any of these stages leads to a disorder of varying severity and rarity.
What are the symptoms for valinemia?
Valinemia is usually present at birth. Symptoms in the newborn period include protein intolerance, metabolic acidosis, frequent Vomiting, failure to thrive, and coma. The condition may become life-threatening. The levels of the amino acid valine in the blood and urine are elevated. Abnormally low muscle tone, excessive drowsiness, and/or hyperactivity can also occur.
What are the causes for valinemia?
Valinemia is a recessive genetic disorder. Recessive genetic disorders occur when an individual inherits the same abnormal gene for the same trait from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.
All individuals carry 4-5 abnormal genes. Parents who are close relatives (consanguineous) have a higher chance than unrelated parents to both carry the same abnormal gene, which increases the risk to have children with a recessive genetic disorder.
What are the treatments for valinemia?
A diet low in valine introduced during early infancy usually improves symptoms of valinemia, and lowers the valine concentrations in the blood to normal levels.
What are the risk factors for valinemia?
Valinemia is a rare metabolic disease marked by unusually elevated amounts of the amino acid valine in the urine and blood.
- Infants with valinemia are said to have a poor appetite, puking, and fail to thrive. In rare situations, the condition is potentially fatal.
- There have also been reports of low muscular tone (hypotonia), excessive sleepiness, hyperactivity, and developmental delay.
- Valinemia is caused by a lack of the enzyme valine transaminase, which is required for valine breakdown (metabolism) in the body.
- It is inherited autosomal recessively; however, the gene laible for the disorder is unknown.
- A low-valine diet (started during early infancy) frequently improves symptoms and restores valine levels to normal.
- Parents who are close relatives (consanguineous) have a higher chance of carrying the same abnormal gene, increasing the risk of having children with a recessive genetic disorder.
Insufficient weight gain,Delayed attainment of developmental milestones,Coma,Inability to thrive
Appetite loss,Protein sensitivity,Acidosis of the metabolism,Vomiting frequently,Muscle tone that is abnormally low (hypotonia),Hyperkinesia,Hyperactivity,Drowsiness that is excessive,Mental and physical growth is delayed