Ultra Fast KETO Boost What is the treatment?Methylmalonic acid ( MMA ), or methyl malonic acid acyduria, is a rare inherited metabolic disorder in which the body is unable to properly break down certain proteins, lipids and cholesterol. As a consequence, a substance called methylmalonyl CoA and other potentially toxic compounds accumulate in the body, which leads to its gradual intoxication and, if not treated, to death.Methylmalonic acidosis, together with propionic, isovaleric and glutaric acidosis, belongs to the group of organic acidosis (acyduria). They are a group of rare congenital metabolic defects that manifest themselves mainly in infants or in early childhood.