Saturday, November 03, 2007
Isovaleric acidemia: Smelly feet are no laughing matter
Isovaleric acidemia (IVA) is a rare genetic condition which causes the smell of sweaty feet. This happens due a build up of isovaleric acid in the body. Isovaleric acidemia (IVA) causes malfunction of certain protein processes, leading to an abnormal build up of organic acids in the blood (organic acidemia), urine (organic aciduria), and tissues can be poison the body. Proteins from food are normally broken into smaller parts called amino acids which provide energy for growth and development. Isovaleric acidemia occurs when there is an inadequate level of enzymes to break down leucine. Isovaleryl-CoA is the breakdown product of leucine which is an essential amino acid. Isovaleric acidemia can present as an acute episode of illness during the first few weeks of a newborn's life, or it may present chronically with intermittent episodes of illness throughout life. Infants who survive an acute neonatal episode will go on to exhibit the chronic intermittent form. The condition is an autosomal recessive genetic trait and is unknowingly passed down from generation to generation. This faulty gene usually emerges when two carriers have children together and pass it to their offspring. The incidence of IVA is approximately 1 in 50,000 live births. Some people with gene mutations that cause isovaleric acidemia are asymptomatic and do not experience any signs and symptoms of the condition. Health problems associated with IVA 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. Most episodes will improve with protein restriction and increased glucose (sugar) intake. Most patients with chronic intermittent IVA have normal development, but some are developmentally delayed, and mild to severe mental retardation can occur. Many children with IVA will develop a natural aversion to protein-rich food. Early detection through newborn screening and good treatment of IVA generally leads to normal development.
A Parent's Guide to IVA
Organic Acidemia Association, Inc. (OAA)