Summary
Propionicacidemia is a frequent autosomal recessive disorder due to propionyl-CoA carboxylase deficiency. Genes causing the disease code for two alpha or beta subunits. A few cases are biotin responsive, a propionyl-CoA carboxylase cofactor. Clinical signs - which are close to those seen in methyl malonic acidemia -appear soon after birth and include ketoacidotic coma, hyperammonemia and convulsions. Onset may be later with recurrent coma or hypotonia, digestive disorders, and intellectual deficit. Apart from acute metabolic decompensation, the major complications are neurological disorders (central grey nuclei), cardiomyopathies, and acute pancreatitis. Diagnosis is made by chromatography of urinary organic acids and plasmatic acylcarnitines with evidence of propionic acid and other derived products. Patients should follow a very strict diet with limited protein intake. Treatment otherwise includes carnitine and alternated cures of antibiotics to destroy intestinal bacteria that produce propionic acid. Treatment by liver transplantation is reserved to only very severe cases. Antenatal diagnosis is feasible* Author: Pr. J-M. Saudubray (March 2004) *
