Propionic acidemia, also known as propionic aciduria or propionyl-CoA carboxylase deficiency (PCC deficiency), is a rare autosomal recessive metabolic disorder, classified as a branched-chain organic acidemia. The disorder presents in the early neonatal period with poor feeding, vomiting, lethargy, and lack of muscle tone. Without treatment, death can occur quickly, due to secondary hyperammonemia, infection, cardiomyopathy, or brain damage.

Reference
Wiki: Propionic acidemia