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. 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. 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. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.