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
125 tests are in the database for this condition.
Check Related conditions for additional relevant tests.
Clinical tests (125 available)
Biochemical Genetics Tests
IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.