title: Early diagnosis of hyperphenylalaninemia due to tetrahydrobiopterin deficiency (malignant hyperphenylalaninemia).
mesh_terms: D001708:Biopterins / Q000031:analogs & derivatives / Q000172:deficiency*; D006801:Humans; D007231:Infant, Newborn; D010649:Phenylalanine / Q000097:blood*; D010661:Phenylketonurias / Q000097:blood* / Q000178:diet therapy; D011621:Pteridines / Q000172:deficiency*
chemical_list: D011621:Pteridines; D001708:Biopterins; D010649:Phenylalanine; C003402:sapropterin