Relationship Between Electroencephalography and Seizure Outcome in Typical Absence Seizures in Children.

BACKGROUND: Typical absence seizures (TAS) are seen in idiopathic generalized epilepsy. Electroencephalography (EEG) contributes to syndrome characterization and counseling in an area where genetics does not currently play a significant role. Prominent interictal EEG findings are seen in juvenile absence epilepsy (JAE) and are thus thought to be associated with less favorable outcome in any TAS case despite lack of evidence. Our study evaluates EEG findings and their association with seizure outcomes in children with TAS. METHODS: Retrospective cohort study of 123 children over 10 years with extensive EEG analysis and medical record review. Phone interviews ascertained longer-term outcomes. EEG reviewers were unaware of outcomes. RESULTS: Total cohort included 123 children with phone review completed in 98. Median follow-up was 5 years 9 months. Seizure freedom was seen in 59% off antiseizure medicines (ASMs). Interictal findings included focal discharges in 29%, fragments of spike-wave (SW) discharges in 82.1%, and generalized interictal discharges in 63.4%. Interictal SW was more likely in those who slept (100%, 18 of 18) versus those who did not (57%, 60 of 105) (P < 0.001). Outcome analysis found no associations between focal or generalized interictal findings and seizure freedom, relapse off ASM, occurrence of other seizure types, or response to first ASM. CONCLUSION: Focal and generalized interictal EEG discharges are common in children with TAS and are not associated with poorer outcomes. These interictal findings were traditionally associated with JAE rather than childhood absence epilepsy and were thus believed to be associated with potentially poorer outcome, which is probably not the case.

Single center analysis of patients with H1N1 vaccine-related narcolepsy and sporadic narcolepsy presenting over the same time period.

STUDY OBJECTIVES: We aimed to describe the clinical features of narcolepsy in patients referred to our sleep center between 2009 and 2016, and to compare these features across age groups and between sporadic vs AS03-adjuvanted H1N1 influenza vaccine-related patients. METHODS: This is a retrospective, consecutive study of adult and pediatric narcolepsy patients in the Republic of Ireland. All participants underwent structured assessments, including polysomnography and the Multiple Sleep Latency Test. Brain magnetic resonance imaging, hypocretin levels, and human leukocyte antigen typing were also carried out on the majority of patients. Patients were compared across age groups as well as etiology. RESULTS: The conditions of 40 (74%) patients were vaccine-related. The median age was 13.5 years and time from symptom onset to diagnosis was 112 weeks. Median time from vaccination to symptom onset was 26 weeks. In children, hypnogogic hallucinations and sleep paralysis were less frequent than in adults (17% vs 67%, P = .018 and 0% vs 75%, P < .0005). Sleep latency determined by the Multiple Sleep Latency Test was shorter in children than adults (median 1.75 vs 4 minutes, P = .011). Patients with vaccine-related and sporadic narcolepsies had typical clinical presentations. Vaccine-related patients had longer polysomnography latency (median 10.5 vs 5 minutes, P = .043), longer stage N2 sleep (209.6 ± 44.6 vs 182.3 ± 34.2 minutes, P = .042), and a trend toward longer total sleep times (P = .09). No differences were noted in relation to Multiple Sleep Latency Test, hypocretin, human leukocyte antigen typing, and magnetic resonance imaging. CONCLUSIONS: Results show that vaccine-related patients greatly outnumbered sporadic patients during the study period and suggest that sporadic and vaccine-related narcolepsy are clinically similar entities.

Narcolepsy in children and young people in Ireland: 2006-2017.

AIM: To describe the population of young people in Ireland diagnosed with narcolepsy with regards to vaccine exposure, symptomatology, investigation results and experience of medical treatment. METHOD: Retrospective review of medical records at the single tertiary referral centre for young people with narcolepsy in Ireland. RESULTS: Sixty-seven patients were diagnosed with narcolepsy between July 2006 and July 2017. Sixty-one (91%) of these developed symptoms after receiving the Pandemrix vaccine. The population was largely homogeneous with low hypocretin (87.5%), HLA DQB1∗0602 positivity (95%) and unremarkable findings on MRI Brain (100%). 77.6% experienced cataplexy; we also measured high levels of obesity, school non-attendance and psychosocial complexity. Symptoms often continued despite treatment, with multiple medications prescribed in 76.1% of patients. Prescription of sodium oxybate was associated with a significant reduction in BMI standard deviation scores at 6 months, with improved IOTF obesity scores seen at 36 month follow-up. CONCLUSIONS: This paper describes the experience of narcolepsy in children and young people in Ireland from 2006 - 2017 at the national tertiary referral centre. Narcolepsy in children and young people in Ireland carries a significant burden of illness, with impact on participation in education as well as physical and mental health. Symptoms can be refractory to medical treatment. Referral to tertiary centres for prompt treatment and multidisciplinary input is essential.