Propionic Acidemia is an autosomal recessive branched-chain organic acidemia, characterized by a deficiency of the propionyl-CoA carboxylase enzyme, which helps in the normal breakdown of several essential amino acids. It is caused by mutations in PCCA and PCCB genes.
Patients may initially present some minor symptoms including poor feeding, vomiting, loss of appetite, hypotonia, and lethargy. Most children with propionic acidemia display different degrees of motor, social, and language delay. They may also have other clinical features, including neutropenia, cardiac abnormalities, periodic thrombocytopenia, hypogammaglobulinemia, developmental retardation, seizures, and coma. In most cases, the condition presents itself in the infantile stage. Rarely, it may manifests during childhood, triggered by stress conditions, such as fasting, or infections.