nonketotic hyperglycinemia

non·ke·tot·ic hy·per·gly·cin·e·mi·a

[MIM*238300]
an inborn error of glycine metabolism, due to a deficiency of glycine dicarboxylase P protein (GCSP), a component of glycine cleavage system; characteristically overwhelming disease in the newborn period, with coma, seizures, and death, or, less often, gradual onset with failure to thrive, focal seizures, and mental retardation; there is massive elevation of plasma glycine, with increased levels in cerebrospinal fluid and urine; plasma hyperosmolality, severe dehydration occur without ketoacidosis; autosomal recessive inheritance; caused by mutation in the GCSP gene on chromosome 9p.

nonketotic hyperglycinemia

[nonkētot′ik]
a usually fatal autosomal-recessive aminoacidopathy with accumulation of glycine in body fluids, particularly the blood, urine, and cerebrospinal fluid. It has neonatal onset and is characterized by lethargy, metabolic acidosis with ketosis, absence of cerebral development, seizures, myoclonic jerks, and frequently coma and respiratory failure. It is caused by a defect in one or more of the enzymes involved in the cleavage of glycine. Also called methylmalonicacidemia, propionicacidemia.
References in periodicals archive ?
Joseph Kendrick, who celebrated his fourth birthday yesterday, is one of only 500 people in the world with rare genetic disorder nonketotic hyperglycinemia.
Mutations in AMT, a gene classically associated with a severe metabolic syndrome known as nonketotic hyperglycinemia, marked by severe seizures and death during infancy.
Intracerebral blood and MRS in neonatal nonketotic hyperglycinemia.
Early myoclonic encephalopathy and nonketotic hyperglycinemia.
Bhamkar RP Colaco P Neonatal nonketotic hyperglycinemia.
A novel missense mutation in a neonate with nonketotic hyperglycinemia.
We obtained CSF by spinal tap from 22 pediatric patients suspected of having inherited metabolic conditions that cause seizures, particularly nonketotic hyperglycinemia, but in whom no diagnosis was made and CSF amino acid concentrations were within normal limits.
Glycine has not been shown to be so consistently elevated at 24 hours of age as to make this useful in screening for nonketotic hyperglycinemia, or NKH.
com NONKETOTIC HYPERGLYCINEMIA See: Acidemia, Organic NONNE-MILROY-MEIGE SYNDROME See: Lymphatic Ma/formations; NOONAN SYNDROME See: Cardio-Facio-Cutaneous Syndrome; Growth Disorders; Heart Disorders; Malignant Hyperthermia; Williams Syndrome (TNSSG) Noonan Syndrome Support Group, Inc.
Although this approach allowed us to diagnose two cases of nonketotic hyperglycinemia, numerous screening samples gave high glycine values that were not reproducible when analyzed the next day.
The patient group comprised 13 children with inborn errors of metabolism (Table 1): 11 with mitochondrial disorders confirmed by analysis of respiratory chain enzyme activities in muscle biopsies [14,15] or PCR analysis of mitochondrial DNA extracted from peripheral blood lymphocytes [16], and 2 with nonketotic hyperglycinemia (NKH) confirmed by assay of glycine cleavage enzyme activity in liver [17].
7 Cyanotic episodes Nonketotic hyperglycinemia 12 0.