ABSTRACT
Methylmalonic acidemia (MMA) represents a family of disorders of the metabolism of branched-chain amino acids in which the activity of methylmalonyl coenzyme A (CoA) mutase is defective. Patients with MMA usually present first with a typical organic acidemia picture of overwhelming illness very in life. Dystonia and weakness profound enough to lead to a wheelchair-bound state has been observed in methylmalonic academia. Prenatal detection of MMA has been accomplished by assay of the activity of methylmalonyl CoA mutase in cultured amniotic cells. The diagnosis of MMA is most readily made by assay of the urine for methylmalonic acid. The diagnosis of MMA is most readily made by assay of the urine for MMA. The treatment of hyperammonemia in the acute crisis of infantile MMA has been expanded by the use of intravenous carbamylglutamate in this disease as well as in propionic academia.
