Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027066 (myoclonus)
 4,275 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Electroencephalographic (EEG) and brainstem auditory evoked response (BAER) findings have not been previously described and correlated with the pathological findings in an autopsied case of neonatal nonketotic hyperglycinemia (NKH). A 38 week gestation male infant presented within two hours of age with stimulus-evoked myoclonus and seizures in the context of progressive coma. Electrographic studies demonstrated cortical myoclonus and electrical seizures exquisitely localized to the midline region as well as a suppression-burst background disturbance. These vertex spike discharges were elicited after tactile stimulation. Prolonged intra-axial latencies for waves III and V were recorded on the BAER on the second day of life. Spongy leukodystrophy was noted on gross and microscopic examination of the brain involving all myelinated tracts especially in the reticular activating system, cerebellar peduncles and optic tracts. Neuropathological confirmation of brainstem involvement emphasizes the role of the nonspecific diffuse somatosensory projection system in the generation of myoclonus and stimulus-evoked seizures in the comatose patient with NKH.
 ...
PMID:Neurophysiological and anatomical correlations in neonatal nonketotic hyperglycinemia. 376 70

An 11-year-old girl with nonketotic hyperglycinemia who typically presented with a picture of early myoclonic encephalopathy in the neonatal period is presented in this article. Treated early with sodium benzoate and dextromethorphan, she became seizure-free, while myoclonus persisted. During examination, multifocal rhythmic myoclonic jerks in gamma frequency enhanced by motor activity were noted. Coherence analysis of the electroencephalography-electromyography relationship indicated a cortical origin of the myoclonic jerks. Observation of this case suggests that rhythmic cortical myoclonus may represent a late evolution of this rare disorder.
 ...
PMID:High-frequency rhythmic cortical myoclonus in a long-surviving patient with nonketotic hypergylcemia. 1818 48

Early myoclonic encephalopathy presents neonatally with fragmented myoclonus and a suppression-burst electroencephalography pattern. We describe a newborn boy with early myoclonic encephalopathy caused by nonketotic hyperglycinemia. He presented with severe hypotonia, progressive apneic episodes, and erratic myoclonus. Screening of deletions in GLDC, using the multiplex ligation-dependent probe amplification method, and a (13)C breath test confirmed the diagnosis of nonketotic hyperglycinemia. Treatment with the N-methyl-d-aspartate receptor antagonist ketamine exerted dramatic suppressive effects on his seizures, and ameliorated his clinical status.
 ...
PMID:Nonketotic hyperglycinemia: proposal of a diagnostic and treatment strategy. 2069 48

Here, we report a male child with Schinzel-Giedion syndrome associated with intramyelinic edema detected on brain magnetic resonance imaging (MRI) and persistent suppression-burst pattern on electroencephalography (EEG) with erratic myoclonus of the extremities and face. Similar to nonketotic hyperglycinemia, Schinzel-Giedion syndrome may be recognized as another causative genetic disease of early myoclonic encephalopathy and vacuolating myelinopathy.
 ...
PMID:Schinzel-Giedion syndrome: a further cause of early myoclonic encephalopathy and vacuolating myelinopathy. 2150 89

The progressive myoclonus epilepsies (PMEs) are a devastating group of rare disorders(1) that manifest with increasing action myoclonus, which is also present at rest but activates with stimuli such as noise, light, or touch. Ultimately, patients become wheelchair-bound and experience early death. Neurologic signs that frequently but not reliably coexist include other seizure types (particularly generalized tonic-clonic), progressive ataxia, and dementia. Typically, presentation is in late childhood or adolescence; however, all ages may be affected. Although distinction from more common forms of genetic generalized epilepsy, particularly juvenile myoclonic epilepsy, may be challenging early on, the presence or evolution of 1) progressive neurologic disability, 2) failure to respond to antiepileptic drug therapy, and 3) background slowing on EEG should suggest PME. Importantly, inappropriate therapy in the genetic generalized epilepsies may result in ataxia, impaired cognition, and uncontrolled seizures, which may mimic PME. PMEs should be distinguished from progressive encephalopathies with seizures (due to degenerative conditions such as GM2 gangliosidosis, nonketotic hyperglycinemia, Niemann-Pick type C, juvenile Huntington and Alzheimer disease) and progressive myoclonic ataxias, which affect predominantly adults with progressive ataxia, myoclonus, few if any tonic-clonic seizures, and without evidence of dementia.(2,3.)
...
PMID:Progressive myoclonic epilepsies: it takes a village to make a diagnosis. 2438 41