Nonketotic hyperglycinemia

Nonketotic hyperglycinemia results from the congenital absence of the glycine cleavage system, which mediates the interconversion of glycine and serine 673... 

Nonketotic hyperglycinemia causes a severe seizure disorder and profound brain damage 673... 

Treatment for nonketotic hyperglycinemia is less effective than that available for other aminoacidurias 674... 

Nonketotic hyperglycinemia causes a severe seizure disorder and profound brain damage. Infants affected by deficiency of the glycine cleavage system become ill with seizures by the first or second day of life. 

Treatment for nonketotic hyperglycinemia is less effective than that available for other aminoacidurias. There is no specific therapy. Exchange transfusion and dialysis usually do not alter the progressive neurological deterioration. Sodium benzoate has been administered in the hope that glycine would react with it to form hippuric acid, but this approach is not helpful. It may be that a combination of benzoate and carnitine therapy is more effective [28]. Similarly, the restriction of dietary protein... 

Deutsch, S. I., Rosse, R. B. and Mastropaolo, J. Current status of NMDA antagonist interventions in the treatment of nonketotic hyperglycinemia. Clin. Neuropharmacol. 21 71-79,1998. 

Alemzadeh, R., Gammeltoft, K. and Matteson, K. Efficacy of low-dose dextromethorphan in the treatment of nonketotic hyperglycinemia. Pediatrics. 97 924—926,1996. 

Table 2.1.9 Changes of blood amino acids in various primary inherited defects and as a result of secondary changes. ASA Argininosuccinic acid, CPS carbamoyl phosphate synthase, LPI Lysinuric protein intolerance, MAD multiple acyl-CoA dehydrogenation, MSUD maple syrup urine disease, NAGS N-acetylglutamate synthase, NKH nonketotic hyperglycinemia, NTBC 2-(2-nitro-4-3 trifluoro-methylbenzoyl)-1,3-cyclohexanedione, OCT Ornithine carbamoyltransferase,...

Additional studies (Gitzelmann et al, 1978) reported that a 6-month-old human patient received strychnine doses of 0.3-1.1 mg/kg/day over an 18-month period without any adverse effects. However, the patient may have had a higher strychnine tolerance as a result of nonketotic hyperglycinemia. 

Halton, D. M., and Krieger, 1. (1980). Studies of glycine metabolism and transport in fibroblasts from patients with nonketotic hyperglycinemia. Pediair. Res. 14,932-934. 

BD, Energy deficiency I, intoxication type of neurological distress (see text) MSUD, maple syrup urine disease NKHG, nonketotic hyperglycinemia. +, possibly present ++, frequently present +++, typically present with high diagnostic significance not typically present. 

Nonketotic hyperglycinemia 605899, 238300 238310 238330 Glycine cleavage system (P, H, T, L proteins) <1 100,000. Lethargy, seizures, myoclonic jerks, hypotonia, hiccups. i... 

Markand ON, Garg BP, Brandt IK. Nonketotic hyperglycinemia electroencephalographic and evoked potential abnormalities. Neurology 1982 32 151-6. 

Tada K. A block in glycine cleavage reaction as a common mechanism in ketotic and nonketotic hyperglycinemia. Pediatr Res 1974 8 721-3. 

Matsuo, S., Inoue, F., Takeuchi, Y., Yoshioka, H., Kinugasa, A., and Sawada, T., Efficacy of tryptophan for the treatment of nonketotic hyperglycinemia A new therapeutic approach for modulating the N-methyl-D-aspartate receptor, Pediatrics, 95(1), 142, 1995. 

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