Postencephalitic epilepsy and drug-resistant epilepsy after infectious and antibody-associated encephalitis in childhood: Clinical and etiologic risk factors
To define the risk factors for postencephalitic epilepsy (PE) and drug-resistant epilepsy (DRE) in childhood following infectious and autoimmune encephalitis, we included 147 acute encephalitis patients with a median follow-up of 7.3 years (range 2–15.8 years). PE was defined as the use of antiepileptic drugs (AEDs) for ≥24 months, and DRE was defined as the persistence of seizures despite ≥2 appropriate AEDs at final follow-up. PE and DRE were diagnosed in 31 (21%) and 15 (10%) of patients, respectively. The features during acute encephalitis predictive of DRE (presented as odds ratio [OR] with confidence intervals [CIs]) were status epilepticus (OR 10.8, CI 3.4–34.3), visual disturbance (6.4, 1.4–29.9), focal seizures (6.2, 1.9–20.6), magnetic resonance imaging (MRI) hippocampal/amygdala involvement (5.0, 1.7–15.4), intensive care admission (4.7, 1.4–15.4), use of >3 AEDs (4.5, 1.2–16.1), MRI gadolinium enhancement (4.1, 1.2–14.2), any seizure (3.9, 1.1–14.4), and electroencephalography (EEG) epileptiform discharges (3.9, 1.3–12.0). On multivariable regression analysis, only status epilepticus remained predictive of DRE in all models. DRE was common in herpes simplex virus (3/9, 33%) and unknown (8/40, 20%) encephalitis, but absent in acute disseminated encephalomyelitis (ADEM) (0/32, 0%), enterovirus (0/18), and anti-N-methyl-d-aspartate receptor–NMDAR encephalitis (0/9). We have identified risk factors for DRE and demonstrated “high-risk,” and “low-risk” etiologies.
Laryngeal motility alteration: A missing link between sleep apnea and vagus nerve stimulation for epilepsy
This study aimed to evaluate the prevalence and the relationship of sleep breathing disorders (SBDs) and laryngeal motility alterations in patients with drug-resistant epilepsy after vagus nerve stimulator (VNS) implantation. Twenty-three consecutive patients with medically refractory epilepsy underwent out-of-center sleep testing before and after VNS implantation. Eighteen eligible subjects underwent endoscopic laryngeal examination post-VNS implantation. Statistical analysis was carried out to assess an association between laryngeal motility alterations and the onset/worsening of SBDs. After VNS implantation, 11 patients showed a new-onset mild/moderate SBD. Half of the patients already affected by obstructive sleep apnea (OSA) showed worsening of SBD. All of the patients with a new-onset OSA had a laryngeal pattern with left vocal cord adduction (LVCA) during VNS stimulation. The association between VNS-induced LVCA and SBD was statistically significant. This study suggests an association between VNS and SBD, hinting to a pivotal role of laryngeal motility alterations. The relationship between SBD and VNS-induced LVCA supports the need to routinely investigate sleep respiratory and laryngeal motility patterns before and after VNS implantation.