TABLE 96.5 INBORN ERRORS OF METABOLISM PRESENTING WITH ENCEPHALOPATHY Urea cycle defects Maple syrup urine disease Nonketotic hyperglycinemia Organic acid disorders Hypervalinemia Phenylketonuria Lysinuric protein intolerance Vomiting, stupor and seizures Hyperammonemia, acidosis with respiratory alkalosis Stupor, seizures, odor of maple syrup Acidosis, hypoglycemia Stupor, seizures, hiccups Hyperglycinemia in CSF, serum, and urine Absence of acidosis or ketones in urine Stupor, coma, tachypnea, vomiting Metabolic acidosis Stupor and developmental delay Vomiting and musty odor Vomiting and hypotonia