Propionic acidemia, also known as propionic aciduria, propionyl-CoA carboxylase deficiency and ketotic glycinemia,^[1] is an autosomal recessive^[2] metabolic disorder, classified as a branched-chain organic acidemia.^[3] The disorder presents in the early neonatal period with progressive encephalopathy. Death can occur quickly, due to secondary hyperammonemia, infection, cardiomyopathy, or basal ganglial stroke.^[4] Propionic acidemia is a rare disorder that is inherited from both parents. Being autosomal recessive, neither parent shows symptoms, but both carry a defective gene responsible for this disease. It takes two faulty genes to cause PA, so there is a 1 in 4 chance for these parents to have a child with PA.

Propionic acidemia is inherited in an autosomal recessive pattern and is found in about 1 in 35,000^[5] live births in the United States. The condition appears to be more common in Saudi Arabia,^[6] with a frequency of about 1 in 3,000.^[5] The condition also appears to be common in Amish, Mennonite and other populations where inbreeding is common.^[7]