Methylmalonic acidemia does not have a high pass rate for retesting. Methylmalonic acidemia is an autosomal recessive genetic disease, if the initial examination is diagnosed or suspected of the disease, then again review pass rate is not high, chromosomal disorders are currently incurable. Methylmalonic acidemia is caused by an abnormality in the chromosomal gene and a lack of related coenzymes in the body, resulting in the inability to convert L-methylmalonic acid to succinic acid, and a large amount of L-methylmalonic acid accumulates in the blood causing a series of symptoms. Methylmalonic acidemia develops in newborns or early infants, and manifests as lethargy, repeated vomiting, respiratory distress, hypotonia, etc. It is accompanied by growth and developmental abnormalities, and some of the affected children have backwardness of intelligence and enlarged liver. Most patients also have ketonemia or ketonuria and hyperammonemia. Half of the children have leukopenia, thrombocytopenia and erythrocytopenia, accompanied by hypoglycemia. If there is a methylmalonic acidemia patient in the family, there is not a high rate of passing the initial examination of the newborn after the initial examination is suspected, and then the reexamination is not passed. There is no effective treatment for this inherited metabolic disease, and a good prenatal diagnosis is an effective measure to prevent the development of this disease.