Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038220 (status epilepticus)
 7,272 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ring chromosome 20 is a rare chromosome disorder characterized by a typical seizure phenotype consisting of complex partial seizures, frequent progression to generalized tonic or tonic-clonic seizures, and nocturnal frontal lobe seizures with frequent episodes of non-convulsive status epilepticus. Development may be normal or mildly delayed, followed by cognitive and behavioral decline after seizure onset. Here, we describe a patient with a typical severe seizure phenotype and a mosaic ring chromosome 20 without loss of p or q subtelomere regions or telomeric sequences. The ring had a longer telomere length than either of the telomere ends of its homologous chromosome 20 by quantitative fluorescence in situ hybridization analysis, suggesting that it might be derived from telomere-telomere fusion. The phenotypic comparison of this patient and other chromosome 20 cases that had terminal deletions of 20qter (n = 1) and 20pter (n = 7), shows that the epilepsy phenotype and electroencephalographic abnormalities are characteristic in patients with ring chromosome 20. Several hypotheses have been proposed to address the elusive mechanisms underlying the seizure disorder in ring chromosome 20. These possibilities include haploinsufficiency of two epilepsy genes CHRNA4 and KCNQ2 located at 20qter, silencing of these genes by a telomere position effect, or microdeletions or rearrangements of genetic material during the ring formation.
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PMID:Mosaic ring 20 with no detectable deletion by FISH analysis: Characteristic seizure disorder and literature review. 1683 34

Ring chromosome 20 (r(20)) syndrome is a rare disease characterized by refractory epilepsy, moderate mental retardation and particular electroencephalographic disorder with non-convulsive status epilepticus. Here, we report a new case of r(20) syndrome in a 12 year old female who presented minimal dysmorphism, generalised tonic-clonic and absence seizures refractory to medical therapy and behavioural troubles. Among 20 cytogenetically analysed cells, 14 (70%) exhibited a 46,XX,r(20)(p13q13.3) karyotype and 6 (30%) showed a normal 46,XX caryotype. Interphasic FISH using centromeric probe of chromosome 20 detects the presence of a chromosome 20 monosomy in 7% and a duplicated ring chromosome 20 in 8% of studied cells. Metaphase FISH using chromosome 20 telomeric probes and specific probes of CHRNA4 and KCNQ2 genes detects the absence of any deletion in the ring chromosome 20. Clinical symptoms of r(20) syndrome are attributed to telomeric partial monosomy generated by ring chromosome and causing an haploinsufficiency of two epilepsy genes CHRNA4 and KCNQ2. However, our patient presents the typical epilepsy disorder but no detectable deletion in the ring chromosome 20. We speculate that clinical features of ring chromosome 20 syndrome are caused by low mosaicism of chromosome 20 monosomy caused by the loss of the ring chromosome 20.
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PMID:Ring chromosome 20 syndrome without deletions of the subtelomeric and CHRNA4--KCNQ2 genes loci. 1785 Nov 50

The ring chromosome 20 syndrome is a rare syndrome characterized by intractable epilepsy with particular electro clinical features including episodes of prolonged confusional state and nocturnal frontal lobe seizures. We report a 17-year-old girl who had intractable epilepsy with frontal seizure and prolonged confusional state secondary to non-convulsive status epilepticus. The diagnosis of ring chromosome 20 was suspected and confirmed by karyotype. The cytogenetic study of CHRNA4 and KCNQ2 genes did not detect deletion in the ring chromosome 20. During video-EEG recording, this girl presented a non-convulsive status epilepticus that lasted more than 20 minutes followed by typical frontal lobe seizure. This association was not previously described, and was probably caused by chromosomal instability.
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PMID:Frontal motor seizure following non-convulsive status epilepticus in ring chromosome 20 syndrome. 2224 17