Hypoglycaemic events resembling focal seizures - a case report and literature review

Purpose: To review the literature, for cases of hypoglycaemia misdiagnosed as epilepsy, including our interesting case of a patient with Type 1 Diabetes Mellitus, diagnosed with focal epilepsy. Methods: A literature search was completed. 20 of 473 studies, with a total of 22 cases found using specified search terms were relevant to this review. The papers identified and reviewed were those that dealt with hypoglycaemia misdiagnosed as epilepsy. The majority are isolated case reports given the rarity of this entity. Results: An underlying insulinoma is the most common cause for hypoglycaemic episodes to be misdiagnosed as epilepsy. Early morning seizures were prominent in 9 of the 22 cases. Conclusion: Although rare, hypoglycaemia is an important differential diagnosis for drug-resistant epilepsy and early morning events may be an indication. We report the first case of recurrent hypoglycaemia from exogenous insulin, misdiagnosed as focal epilepsy with an available video EEG. The unusual presentation appeared clinically indistinct from recurrent focal seizures.</p

Teaching Video NeuroImages: Vagoglossopharyngeal neuralgia mimicking a seizure.

A 79-year-old woman with a history of partial thyroidectomy for multinodular goiter presented with acute onset episodic left ear pain followed by collapse with loss of awareness and limb jerking. Video EEG captured stereotyped episodes (video, links.lww.com/WNL/A287) with corresponding bradycardia and asystole for several seconds without ictal changes. A diagnosis of vagoglossopharyngeal neuralgia was made. She became symptom-free with eslicarbazepine and pacemaker insertion. Approximately 10% of patients with glossopharyngeal neuralgia experience bradycardia and syncope. Activation of the vagus nerve (dorsal motor nucleus) by excessive input from the glossopharyngeal nerve (via tractus solitarius) may lead to potential cardiac arrhythmias.</p

Simultaneous occurrence of nonepileptic and epileptic seizures during a single period of in-patient video-electroencephalographic monitoring

Epilepsy and psychogenic nonepileptic seizures (PNES) can coexist and may present intwo forms: sequential and simultaneous. In sequential presentations, epileptic seizures(ES) are treated and PNES emerge later. Simultaneous recording of ES and PNES byvideo-electroencephalogram (vEEG) is less well described. We retrospectivelyreviewed all patients diagnosed with PNES by vEEG following standard seizure induc-tion practices over a 21-month period. Within this cohort, we established the preva-lence of coexisting epilepsy using clinical and electrographic data acquired from ourepilepsy-specific patient record. We identified patients with simultaneous PNES andES recorded during a single vEEG admission, establishing the frequency and emergenttiming of each type. Of our 262 monitored patients, 59 were diagnosed with PNES.Nineteen of the patients with PNES had coexisting epilepsy (prevalence rate of 7.3% or32% of those with PNES). Sixteen patients had PNES and ES recorded during the same admission, and the remaining three patients had sequential PNES following successfultreatment of ES. PNES occurred earlier (mean, within 1.21 days), with ES occurring later (mean, within 4.86 days). The simultaneous occurrence of PNES and ES recorded during a single admission is more common than previously reported. Identifying this group of patients may require a significantly longer period of vEEG monitoring and a detailed analysis of each individual’s historical seizure events.</p

A retrospective study of the correlation between duration of monitoring in the epilepsy monitoring unit and diagnostic yield

Objective Long-term video-electroencephalographic (LTVEM) monitoring is a valuable tool in the evaluation of paroxysmal clinical events. However, vEEG itself is costly. Hence, we aimed to establish if longer duration of monitoring (DOM) is associated with higher diagnostic yield. Method A retrospective review of patients admitted into the epilepsy monitoring unit (EMU) for the diagnostic evaluation of paroxysmal events was performed. Patients’ demographic, clinical characteristics, and vEEG data were analyzed. In the cohort of patients with DOM > 7 days, the reasons for prolonged DOM were identified and the differences in clinical characteristics and vEEG data between conclusive and inconclusive studies were analyzed. Result A total of 501 patients were included. Four hundred and thirty-six (87 %) patients had conclusive studies. Of these patients, 67.9 % patients with conclusive studies received diagnosis within the first 7 days of monitoring with the highest on day 7. The likelihood of conclusive studies decreased beyond 7 days. A total of 175 had DOM > 7 days, of which 140 (80 %) had conclusive studies. In the cohort with DOM > 7 days, patients with previous abnormal routine EEG, previous vEEG monitoring, first event recorded before day 5 of admission and ≥1 events recorded during vEEG monitoring were more likely to have conclusive studies. The most common reason for prolonging DOM beyond 7 days was to adequately record multiple semiologically distinctive events (76 %). Conclusion Our study supports that longer DOM is associated with an increase in diagnostic yield. More than one-third of our cohort were monitored beyond 7 days with majority (80 %) being conclusive. Our findings may guide clinicians in planning the DOM and predicting the likelihood of conclusive vEEG studies in patients with prolonged DOM based on the clinical characteristics and vEEG data.</p

Vagus nerve stimulation in refractory idiopathic generalised epilepsy: an Irish retrospective observational study

Objective: Refractory idiopathic generalised epilepsy (IGE; also known as genetic generalised epilepsy) is a clinical challenge due to limited available therapeutic options. While vagus nerve stimulation (VNS) is approved as an adjunctive treatment for drug-resistant focal epilepsy, there is limited evidence supporting its efficacy for refractory IGE. Methods: We conducted a single-centre retrospective analysis of adult IGE patients treated with VNS between January 2003 and January 2022. We analysed the efficacy, safety, tolerability, stimulation parameters and potential clinical features of VNS response in this IGE cohort. Results: Twenty-three IGE patients were implanted with VNS between January 2003 and January 2022. Twenty-two patients (95.65%) were female. The median baseline seizure frequency was 30 per month (interquartile range [IQR]= 140), including generalised tonic-clonic seizures (GTCS), absences, myoclonus, and eyelid myoclonia with/without absences. The median number of baseline anti-seizure medications (ASM) was three (IQR= 2). Patients had previously failed a median of six ASM (IQR= 5). At the end of the study period, VNS therapy remained active in 17 patients (73.9%). amongst patients who continued VNS, thirteen (56.5% of the overall cohort) were considered responders (≥50% seizure frequency reduction). Amongst the clinical variables analysed, only psychiatric comorbidity correlated with poorer seizure outcomes, but was non-significant after applying the Bonferroni correction. Although 16 patients reported side-effects, none resulted in the discontinuation of VNS therapy. Significance: Over half of the patients with refractory IGE experienced a positive response to VNS therapy. VNS represents a viable treatment option for patients with refractory IGE, particularly for females, when other therapeutic options have been exhausted.</p