Non-ketotic hyperglycinemia
- Synonyms
- AMT-Related Glycine Encephalopathy; GLDC-Related Glycine Encephalopathy; Glycine encephalopathy; Nonketotic hyperglycinemia
- Modes of inheritance
- Autosomal recessive inheritance (Orphanet)
Summary
Excerpted from the GeneReview:Nonketotic hyperglycinemia (NKH) is the inborn error of glycine metabolism defined by deficient activity of the glycine cleavage enzyme system (GCS), which results in accumulation of large quantities of glycine in all body tissues including the brain. Based on ultimate outcome NKH is categorized into severe NKH (no developmental progress and intractable epilepsy) and attenuated NKH (variable developmental progress and treatable or no epilepsy). The majority of children with NKH have onset in the neonatal period manifest as progressive lethargy evolving into profound coma and marked hypotonia; 85% have severe NKH and 15% attenuated NKH. Those with onset between two weeks and three months typically present with hypotonia; 50% have severe NKH and 50% attenuated NKH. Those with onset after age three months have attenuated NKH. Severe versus attenuated NKH is consistent within families, but the degree of developmental progress in those with attenuated NKH can vary.
- Full text of GeneReview (by section):
- Summary
- GeneReview Scope
- Diagnosis
- Clinical Characteristics
- Genetically Related (Allelic) Disorders
- Differential Diagnosis
- Management
- Genetic Counseling
- Resources
- Molecular Genetics
- Chapter Notes
- References
- Authors:
- Johan LK Van Hove
- Curtis Coughlin
- Michael Swanson
- view full author information
Available tests
127 tests are in the database for this condition.
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Clinical tests (127 available)
Biochemical Genetics Tests
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