| HYPERGLYCINEMIA, NON-KETOTIC (NKH) | |
| NKH; GLYCINE ENCEPHALOPATHY; GLYCINE CLEAVAGE SYSTEM DEFICIENCY | |
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605899
OMIM = Online Mendelian Inheritance of Men | |
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407 | |
| glycine cleavage system defect GCS (P-protein, T-protein, H-protein) | |
| rare (1:76000, 1:12000 northern Finland) autosomal recessive atypical patients with low glycine levels in CSF and plasma, transient form has been described in 5 patients, few patients never developed seizures | |
| Laboratory findings | Glycine inc (cerebrospinal fluid) Glycine inc (urine) Glycine inc (plasma) Glycine cleavage enzyme dec (lymphoblasts) Glycine cleavage enzyme dec (liver) |
| Symptoms | EEG abnormalities [-] MRI, brain, abnormalities [-] seizures apnea ataxia blindness, visual loss, visual impairment chorea or athetosis corpus callosum, agenesis/hypoplasia epilepsy feeding difficulties, poor feeding hiccups hydrocephalus hypertonia, spasticity hypotonia lethargy, drowsiness, apathy neurological deterioration optic atrophy psychomotor retardation Amino acid, spinal fluid Amino acids, plasma behavior, hyperactive, restless coma early death EEG, burst suppression [-] EEG: hypsarrhythmia [-] irritability mental retardation MRI, brain, white matter abnormalities [-] onset, childhood onset, infancy onset, neonatal pulmonary hypertension spastic diplegia/quadriplegia/tetraplegia speech development, delayed, abnormal tachypnea, hyperpnea, dyspnea, hyperventilation |