title: Ring chromosome 20: a pediatric potassium channelopathy responsive to treatment with ezogabine.
abstract: BACKGROUND
  Ring chromosome 20 is a genetic disorder characterized by intractable epilepsy, behavioral problems, and cognitive deficit. The potassium channel-coding gene KCNQ2 is localized at the locus q13.3 on the chromosome 20, the most common site where the ring occurs. Ezogabine is the first potassium channel opener marketed in the United States.
  
  
  METHODS
  We describe an 8-year-old girl with mosaic ring chromosome 20 and refractory epilepsy who had a remarkable improvement in seizure control with ezogabine.
  
  
  CONCLUSIONS
  This is the first report using the new antiepileptic drug ezogabine to treat pediatric epilepsy. We hypothesize that ring chromosome 20 patients have epilepsy related to abnormalities in the potassium channels, making it susceptible for treatment with potassium channel openers.
authors.affiliation: Section of Neurology, Department of Pediatrics, St. Christopher's Hospital for Children, Drexel University College of Medicine, Philadelphia, Pennsylvania.
authors.forename: Diana J
authors.initials: DJ
authors.lastname: Walleigh
authors.forename: Agustin
authors.initials: A
authors.lastname: Legido
authors.forename: Ignacio
authors.initials: I
authors.lastname: Valencia
mesh_terms: D000927:Anticonvulsants / Q000627:therapeutic use*; D002219:Carbamates / Q000627:therapeutic use*; D053447:Channelopathies / Q000188:drug therapy* / Q000235:genetics*; D002648:Child; D002890:Chromosomes, Human, Pair 20; D005260:Female; D006801:Humans; D010655:Phenylenediamines / Q000627:therapeutic use*; D015221:Potassium Channels / Q000235:genetics*; D012303:Ring Chromosomes
chemical_list: D000927:Anticonvulsants; D002219:Carbamates; D010655:Phenylenediamines; D015221:Potassium Channels; C101866:ezogabine
keywords: epilepsy; ezogabine; potassium channel openers; ring chromosome 20