STXBP1 and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy: From the patients included in the refractory seizure group, two patients were diagnosed with Landau–Kleffner syndrome, two with tuberous sclerosis or Lennox–Gastaut syndrome, one with Rett-like syndrome (STXBP1 epilepsy), two with Dravet syndrome and one with West syndrome.