Neonatal type of nonketotic hyperglycinemia

Two infants with the neonatal type of nonketotic hyperglycinemia that had m anifested as early neonatal consciousness disturbance are presented. Transi ent hyperammonemia had been detected in both initially. High levels of glyc ine in plasma and cerebrospinal fluid disturb the nervous system, causing v ariable manifestations of this disease. Both cases were complicated by intr acranial hemorrhage, which has never before been reported. After treatment with sodium benzoate and dextromethorphan, some neurologic improvement was observed, although the glycine levels did not lower. Recent clinical trials are reviewed, and because of the unfavorable outcomes, the special need fo r prenatal diagnosis is highlighted. (C) 1999 by Elsevier Science Inc. All rights reserved.