How reliable is ictal duration to differentiate psychogenic nonepileptic seizures from epileptic seizures?

Recent advances in understanding the neurobiology of pediatric functional neurological disorder

INTRODUCTION

Functional neurological disorder (FND) is a neuropsychiatric disorder that manifests in a broad array of functional motor, sensory, or cognitive symptoms, which arise from complex interactions between brain, mind, body, and context. Children with FND make up 10%-20% of presentations to neurology services in children's hospitals and up to 20% of adolescents admitted to hospital for the management of intractable seizures.

AREAS COVERED

The current review focuses on the neurobiology of pediatric FND. The authors present an overview of the small but growing body of research pertaining to the biological, emotion-processing, cognitive, mental health, physical health, and social system levels.

EXPERT OPINION

Emerging research suggests that pediatric FND is underpinned by aberrant changes within and between neuron-glial (brain) networks, with a variety of factors - on multiple system levels - contributing to brain network changes. In pediatric practice, adverse childhood experiences (ACEs) are commonly reported, and activation or dysregulation of stress-system components is a frequent finding. Our growing understanding of the neurobiology of pediatric FND has yielded important flow-on effects for assessing and diagnosing FND, for developing targeted treatment interventions, and for improving the treatment outcomes of children and adolescents with FND.

Dissociative seizures in the emergency room: room for improvement

BACKGROUND

Dissociative seizures, also known as functional or psychogenic non-epileptic seizures, account for 11%-27% of all emergency seizure presentations. Misdiagnosis as epileptic seizures is common and leads to ineffective and potentially harmful treatment escalations. We assess the potential for diagnostic improvement at different stages of emergency workup and estimate the utility of benzodiazepines.

METHODS

A retrospective study of all emergency presentations with a discharge diagnosis of acute dissociative seizures seen at a university hospital 2010-2022 was performed to assess clinical characteristics and emergency decision-making.

RESULTS

Among 156 patients (73% female, median 29 years), 15% presented more than once for a total of 203 presentations. Half of seizures were ongoing at first medical contact; prolonged seizures and clusters were common (23% and 24%). Diagnostic accuracy differed between on-site emergency physicians and emergency department neurologists (12% vs 52%). Typical features such as eye closure, discontinuous course and asynchronous movements were common. Benzodiazepines were given in two-thirds of ongoing seizures, often in high doses and preferentially for major hyperkinetic semiology. Clinical response to benzodiazepines was mixed, with a minority of patients remaining either unaffected (16%) or becoming critically sedated (13%). A quarter of patients given benzodiazepines by emergency medical services were admitted to a monitoring unit, 9% were intubated.

CONCLUSIONS

Improved semiological assessment could reduce early misdiagnosis of dissociative seizures. Although some seizures seem to respond to benzodiazepines, critical sedation is common, and further studies are needed to assess the therapeutic ratio.

Psychogenic non-epileptic seizures with and without epilepsy: Exploring the influence of co-existing psychiatric disorders on clinical characteristics and outcomes

BACKGROUND AND OBJECTIVES

Psychogenic non-epileptic seizures (PNES) are commonly associated with co-existing psychiatric disorders. The relationship between psychiatric factors and PNES episodes with and without epilepsy remains understudied. We reviewed co-existing psychiatric disorders in PNES-only, PNES with epilepsy aiming to examine whether these co-existing disorders associated with PNES clinical presentation and long-term outcomes.

METHODS

We conducted a retrospective, longitudinal cohort study of patients with PNES diagnosed at our EMU from May 2000 to April 2008, with follow-up clinical data until September 2015. We categorized patients into three groups: PNES-only, PNES+ definite epilepsy, and PNES+ possible/probable epilepsy.

RESULTS

In total, 271 patients with PNES were identified: 194 had PNES-only, 30 had PNES+ possible or probable epilepsy, and 47 had PNES+ definite epilepsy. No significant differences were observed in the prevalence of depression, anxiety, post-traumatic stress disorder (PTSD), substance abuse, or suicidal thoughts among the three groups. Similarly, no differences in co-existing psychiatric disorders characteristics were discovered among patients grouped by various durations and frequencies of PNES episodes. At EMU admission, for PNES-only patients total of 130/194 patients (67%) were on ASMs, and 64/194 (32.9%) were not. PNES-only not on ASM were the most likely to report at least two of the three main psychiatric disorders (depression, anxiety, and PTSD; p = 0.01). At the final follow-up, 68/130 (52.3%) and 92/130 (70.8%) patients were able to discontinue or reduce their ASM intake, respectively, with no significant differences in co-existing psychiatric disorders among them (p < 0.001). Overall, 51.6% or 31.3% of patients reported reduced or resolved PNES episodes, respectively. Further, this reduction and resolution of PNES episode were not affected by any psychological variable.

CONCLUSIONS

Co-existing psychiatric disorders prevalence did not differ between patients with PNES-only and those with coexisting epilepsy. Further, co-existing psychiatric disorders characteristics did not reliably predict PNES episode duration, frequency, reduction, or resolution. For patients with PNES-only, the presence of co-existing psychiatric disorders did not predict the rate at which ASMs could be reduced or discontinued.

Functional Neurological Disorder: Diagnostic Pitfalls and Differential Diagnostic Considerations

Functional neurologic disorder (FND) is a "rule-in" diagnosis, characterized by positive examination signs or semiological features. Similar to other clinical diagnoses, providers should ideally see robustly present features, including if possible the identification of multiple features consistent with FND for the diagnosis to be made with a high degree of certainty. Diagnostic pitfalls need to be guarded against and vary depending on FND symptom subtype and the specific patient presentation. This perspective article aims to review pitfalls based on an FND symptom subtype, as well as discuss differential diagnostic considerations with respect to both neurologic and psychiatric entities.

Ictal crying in epileptic seizures and psychogenic nonepileptic seizures: What are the hints to differentiate them?

OBJECTIVES

Ictal crying (IC) is a quite rare semiological manifestation of epileptic seizures (ESs) and it has been mostly reported in psychogenic nonepileptic seizures (PNESs). However, labeling IC as a pathognomonic sign of PNES can be harmful. We first aimed to investigate IC frequency in ES and PNES and highlight the differences of IC between ES and PNES. Secondly, we aimed to analyze etiology, detailed semiology, treatment options, and outcome of patients with IC in ES in more detail.

METHODS

We retrospectively screened all video-EEG monitoring unit reports from Hacettepe University Hospitals' Epilepsy Center over a 20-year period (1996-2017) for the diagnosis of IC. We included the patients with IC who had at least one documented seizure. Patients who had IC with both facial expression and vocalization compatible with crying with or without weeping and subjective feeling of sadness, were included in the study. We classified patients with IC as ES and PNES. Demographic, historical, clinical, neuroimaging, electrophysiological parameters, video-EEG data, treatment options, and prognosis of all patients were recorded. Demographic, clinical, and video-EEG data were compared between ES and PNES.

RESULTS

During the study period, 1983 patients were investigated. Six patients (all female) with ES and 37 patients (33 female) with PNES were identified. When we compared patients with PNES and ES with IC, the number of ASMs taken and duration of disease were significantly higher in patients with ES than PNES. Longer duration of seizure, longer duration of crying component, late onset of crying component in seizure, early responsiveness after seizure, not occurring during sleep, accompanied by eye closure and weeping, were found significantly higher in patients with PNES. Besides, if we analyze ES group in more detail, all had medical treatment refractory focal epilepsy and two of them whose IC was seen as an early semiological manifestation of their seizures had good outcome after nondominant anterior temporal lobectomy (ATL)+amygdalohippocampectomy (AH). However, three patients had various cortical lesions apart from temporal lobe on MRI and one patient had focal epilepsy with frontal lobe semiology with negative MRI.

CONCLUSION

Although the most common etiology for IC is PNES and it is rarely seen in ES, it can be harmful to label ictal crying as a pathognomonic sign for PNES. We proposed that there are some semiological differences in terms of IC between PNES and ES. These differences may help to distinguish IC in PNES and ES in daily practice. Moreover, it can be speculated that nondominant temporal lobe involvement may be associated with IC in ES.

One Patient, Three Providers: A Multidisciplinary Approach to Managing Common Neuropsychiatric Cases

BACKGROUND

Neuropsychiatric cases require a multidisciplinary approach for effective management. This paper presented case-based discussions on migraine, dementia, epilepsy, mood disorders, neuralgia, and psychosis from the perspectives of a family physician, neurologist, and psychiatrist. The goal was to highlight the importance of collaboration between healthcare providers in managing these complex cases.

METHODS

The paper was based on the proceedings of the Mediterranean Neuropsychiatry Symposium, where experts from family medicine, neurology, and psychiatry came together for comprehensive case-based discussions. The CARE framework (Case Report, Appraisal, Research, and Education) was developed to guide reporting and evaluation of case reports in clinical practice.

RESULTS

Six cases were presented and discussed, highlighting the importance of a multidisciplinary approach in managing neuropsychiatric cases. The cases included chronic migraine with medication overuse, memory dysfunction with language and behavioral problems, refractory epileptic seizures with subjective sensory symptoms, bipolar affective disorder with normal pressure hydrocephalus, postherpetic neuralgia in a case with bipolar affective disorder, and psychosis with recurrent attacks with the abuse of several substances.

CONCLUSION

A biopsychosocial multidisciplinary approach is essential for managing neuropsychiatric cases effectively on behalf of the patients and public health of the country. The CARE framework can guide the reporting and evaluation of case reports in clinical practice, ensuring that patients receive comprehensive and effective care. Healthcare providers should collaborate to provide the best possible care for patients with complex and multifaceted needs.

Latency of epileptic and psychogenic nonepileptic seizures

BACKGROUND

 Due to their semiological similarities, psychogenic nonepileptic seizures (PNESs) can occasionally hardly be differentiated from epileptic seizures (ESs), and long-term video-electroencephalographic monitoring (VEM) is needed for the differential diagnosis.

OBJECTIVE

 To investigate the time of the first clinical event and its distribution on the days of VEM in ES and PNES patients.

METHODS

 In total, a consecutive series of 48 PNES and 51 ES patients matched for gender and age were retrospectively and consecutively evaluated. The time distribution of the seizures during the day was noted. Seizure latency was determined as the time in hours from the start of the video-electroencephalographic recording to the first clinical event.

RESULTS

 The seizure latency was significantly shorter in PNES patients compared to ES patients (p < 0.001). Seventy-two percent of PNES patients and 49.1% of ES patients had their first seizure in the 24 hours of video-EEG recording (p = 0.023). Recording longer than 48 hours was required for 12.5% of PNES patients and 37.3% of ES patients (p = 0.006). While ESs were almost evenly distributed throughout the day, most PNESs occurred during the evening hours (p = 0.011).

CONCLUSION

 We observed that the PNESs appeared earlier than the ESs in the VEM and were concentrated during daylight hours. Although not strictly reliable, seizure latency can contribute to the differential diagnosis of ES and PNES.

Evidence-Based Mind-Body Interventions for Children and Adolescents with Functional Neurological Disorder

LEARNING OBJECTIVES

• Develop and implement treatment plans for children and adolescents with functional neurological disorder (FND)• Outline a plan to increase awareness and standardize the care for patients with FND using evidence-based interventions.

ABSTRACT

Functional neurological disorder (FND) in children and adolescents involves the biological embedding of lived experience in the body and brain. This embedding culminates in stress-system activation or dysregulation and in aberrant changes in neural network function. In pediatric neurology clinics, FND represents up to one-fifth of patients. Current research shows good outcomes with prompt diagnosis and treatment using a biopsychosocial, stepped-care approach. At present, however-and worldwide-FND services are scarce, the result of long-standing stigma and ingrained belief that patients with FND do not suffer from a real ("organic") disorder and that they therefore do not require, or even deserve, treatment. Since 1994, the Mind-Body Program for children and adolescents with FND at The Children's Hospital at Westmead in Sydney, Australia-run by a consultation-liaison team-has delivered inpatient care to hundreds of patients with FND and outpatient care to hundreds of others. For less-disabled patients, the program enables community-based clinicians to implement biopsychosocial interventions locally by providing a positive diagnosis (by a neurologist or pediatrician), a biopsychosocial assessment and formulation (by clinicians from the consultation-liaison team), a physical therapy assessment, and clinical support (from the consultation-liaison team and the physiotherapist). In this Perspective we describe the elements of a biopsychosocial mind-body program intervention capable of providing, as needed, effective treatment to children and adolescents with FND. Our aim is to communicate to clinicians and institutions around the world what is needed to establish effective community treatment programs, as well as hospital inpatient and outpatient interventions, in their own health care settings.

Duration of epileptic seizure types: A data-driven approach

OBJECTIVE

To determine the duration of epileptic seizure types in patients who did not undergo withdrawal of antiseizure medication.

METHODS

From a large, structured database of 11 919 consecutive, routine video-electroencephalograpy (EEG) recordings, labeled using the SCORE (Standardized Computer-Based Organized Reporting of EEG) system, we extracted and analyzed 2742 seizures. For each seizure type we determined median duration and range after removal of outliers (2.5-97.5 percentile). We used surface electromyography (EMG) for accurate measurement of short motor seizures.

RESULTS

Myoclonic seizures last <150 ms, epileptic spasms 0.4-2 s, tonic seizures 1.5-36 s, atonic seizures 0.1-12,5 s, when measured using surface EMG. Generalized clonic seizures last 1-24 s. Typical absence seizures are rarely longer than 30 s (2.75-26.5 s) and atypical absences last 2-100 s. In our patients, the duration of focal aware (median: 27 s; 1.25-166 s) and impaired awareness seizures (median: 42.5 s; 9.5-271 s) was shorter than reported previously in patients undergoing withdrawal of antiseizure medication. All focal seizures terminated within 10 min. Median duration of generalized tonic-clonic seizures was 79.5 s (57-102 s) and of focal-to-bilateral tonic-clonic seizures was 103.5 (77.5-237 s). All tonic-clonic seizures terminated within 5 min.

SIGNIFICANCE

This comprehensive list of seizure durations provides important information for characterizing seizures and diagnosing patients with epilepsy. The upper limits of seizure durations are helpful in early recognition of imminent status epilepticus.

Using Semiology to Classify Epileptic Seizures vs Psychogenic Nonepileptic Seizures: A Meta-analysis

Background and objectives:

Misdiagnosis of psychogenic nonepileptic seizures (PNES) and epileptic seizures (ES) is common. In the absence of the diagnostic gold standard (video EEG), clinicians rely on semiology and clinical assessment. However, questions regarding the diagnostic accuracy of different signs remain. This meta-analysis aims to evaluate the diagnostic accuracy of semiology in PNES and ES.

Methods:

We systematically searched PubMed, PsycInfo and Medline for original research publications published before 8 February 2021 with no restriction on search dates to identify studies that compared semiology in ES and PNES in epilepsy monitoring units. Non-English publications, review articles, studies reporting on only PNES or ES and studies limited to patients with developmental delay were excluded. Study characteristics and proportions of ‘event groups’ and ‘patient groups’ demonstrating signs were extracted from each article. Bivariate analysis was conducted, and data were pooled in a random effects model for meta-analysis. The I2 statistic was calculated to assess statistical heterogeneity. The QUADAS-2 tool was utilized to assess risk of bias in included studies. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were calculated. A PLR > 10 or an NLR < 0.1 has a large impact on the post-test probability of a diagnosis (ES or PNES) whereas a PLR between 5-10 or an NLR between 0.1- 0.2 has a moderate impact on the post-test probability of a diagnosis (ES or PNES).

Results:

The meta-analysis included 14 studies comprising of 800 patients with ES and 452 patients with PNES. For PNES, ictal eye closure (PLR 40.5 95%CI: 16.2-101.3; I2 = 0, from three studies) and asynchronous limb movements (PLR 10.2; 95%CI: 2.8-37.7; I2 = 0, from three studies) reached a PLR threshold > 5. No single sign reached a PLR threshold >5 for ES.

Conclusions:

While all signs require interpretation in the overall clinical context, the presence of ictal eye closure and asynchronous limb movements are reliable discriminative signs for PNES.

Diagnosis and management of functional neurological disorder

Functional neurological disorder (FND), previously regarded as a diagnosis of exclusion, is now a rule-in diagnosis with available treatments. This represents a major step toward destigmatizing the disorder, which was often doubted and deemed untreatable. FND is prevalent, generally affecting young and middle aged adults, and can cause severe disability in some individuals. An early diagnosis, with subsequent access to evidence based rehabilitative and/or psychological treatments, can promote recovery-albeit not all patients respond to currently available treatments. This review presents the latest advances in the use of validated rule-in examination signs to guide diagnosis, and the range of therapeutic approaches available to care for patients with FND. The article focuses on the two most frequently identified subtypes of FND: motor (weakness and/or movement disorders) and seizure type symptoms. Twenty two studies on motor and 27 studies on seizure type symptoms report high specificities of clinical signs (64-100%), and individual signs are reviewed. Rehabilitative interventions (physical and occupational therapy) are treatments of choice for functional motor symptoms, while psychotherapy is an emerging evidence based treatment across FND subtypes. The literature to date highlights heterogeneity in responses to treatment, underscoring that more research is needed to individualize treatments and develop novel interventions.

Misdiagnosis of prolonged psychogenic non-epileptic seizures as status epilepticus: epidemiology and associated risks

OBJECTIVE

To determine the epidemiology of prolonged psychogenic non-epileptic seizures (pPNES) misdiagnosed as status epilepticus, as well as the risks associated with non-indicated treatment.

METHODS

We performed an individual patient data analysis from the Rapid Anticonvulsant Medication Prior to Arrival Trial (RAMPART) and the Established Status Epilepticus Treatment Trial (ESETT) to assess incidence, patient characteristics and clinical course of misdiagnosed pPNES.

RESULTS

Among 980 patients aged 8 years or older diagnosed and treated for status epilepticus in RAMPART and ESETT, 79 (8.1%) were discharged with a final diagnosis of pPNES. The relative incidence was highest in adolescents and young adults (20.1%). The typical female preponderance seen in that age bracket was not evident in children and older adults. Adverse effects, including respiratory depression and intubation, were documented in 26% of patients with pPNES receiving benzodiazepines in RAMPART and 33% of patients receiving additional second-line medication in ESETT. In ESETT, patients who were treated with benzodiazepines before hospital admission had higher rates of unresponsiveness and severe adverse effects than those treated after admission, suggesting cumulative effects of accelerated treatment momentum. Across trials, one in five patients with pPNES were admitted to an intensive care unit.

CONCLUSIONS

Misdiagnosis and treatment of pPNES as status epilepticus are a common and widespread problem with deleterious consequences. Mitigating it will require training of emergency staff in semiological diagnosis. Status epilepticus response protocols should incorporate appropriate diagnostic re-evaluations at each step of treatment escalation, especially in clinical trials.

Digital Semiology: A Prototype for Standardized, Computer-Based Semiologic Encoding of Seizures

Video-EEG monitoring (VEM) is imperative in seizure classification and presurgical assessment of epilepsy patients. Analysis of VEM is currently performed in most institutions using a freeform report, a time-consuming process resulting in a non-standardized report, limiting the use of this essential diagnostic tool. Herein we present a pilot feasibility study of our experience with “Digital Semiology” (DS), a novel seizure encoding software. It allows semiautomated annotation of the videos of suspected events from a predetermined, hierarchal set of options, with highly detailed semiologic descriptions, somatic localization, and timing. In addition, the software's semiologic extrapolation functions identify characteristics of focal seizures and PNES, sequences compatible with a Jacksonian march, and risk factors for SUDEP. Sixty episodes from a mixed adult and pediatric cohort from one level 4 epilepsy center VEM archives were analyzed using DS and the reports were compared with the standard freeform ones, written by the same epileptologists. The behavioral characteristics appearing in the DS and freeform reports overlapped by 78–80%. Encoding of one episode using DS required an average of 18 min 13 s (standard deviation: 14 min and 16 s). The focality function identified 19 out of 43 focal episodes, with a sensitivity of 45.45% (CI 30.39–61.15%) and specificity of 87.50% (CI 61.65–98.45%). The PNES function identified 6 of 12 PNES episodes, with a sensitivity of 50% (95% CI 21.09–78.91%) and specificity of 97.2 (95% CI 88.93–99.95%). Eleven events of GTCS triggered the SUDEP risk alert. Overall, these results show that video recordings of suspected seizures can be encoded using the DS software in a precise manner, offering the added benefit of semiologic alerts. The present study represents an important step toward the formation of an annotated video archive, to be used for machine learning purposes. This will further the goal of automated VEM analysis, ultimately contributing to wider utilization of VEM and therefore to the reduction of the treatment gap in epilepsy.

Predictive semiology of psychogenic non-epileptic seizures in an epilepsy monitoring unit

Introduction

The diagnosis of psychogenic nonepileptic seizures (PNES) is a common clinical dilemma. We sought to assess the diagnostic value of four ictal signs commonly used in differentiating PNES from epileptic seizures (ES).

Methods

We retrospectively reviewed consecutive adult video-electroencephalogram (VEM) studies conducted at a single tertiary epilepsy center between May 2009 and August 2016. Each event was assessed by a blinded rater for the presence of four signs: fluctuating course, head shaking, hip thrusting, and back arching. The final diagnosis of PNES or ES was established for each event based on clinical and VEM characteristics. All ES were pooled regardless of focal or generalized onset. We analyzed the odds ratio of each sign in PNES in comparison to ES with adjustment for repeated measures using logistic regression. Additionally, we calculated the sensitivity, specificity, predictive values, and likelihood ratios of each sign to diagnose PNES.

Results

A total of 742 events from 140 VEM studies were assessed. Fluctuating course (odds ratio (OR) 37.37, 95% confidence interval (CI) 13.56–102.96, P < 0.0001), head shaking (OR 2.95, 95% CI 1.26–6.79, P = 0.012), and hip thrusting (OR 4.28, 95% CI 1.21–15.18, P = 0.02) were each significantly predictive of PNES. Fluctuating course had the highest sensitivity (76.16%). Back arching (OR 1.06, 95% CI 0.35–3.20, P = 0.92) was not significantly associated with PNES.

Conclusion

Fluctuating course, head shaking, and hip thrusting are semiological features significantly more common in PNES than ES. Fluctuating course is the most reliable sign. Back arching does not appear to differentiate PNES from ES.

Evaluation and Management of Seizures and Status Epilepticus

Seizures are frequently triggered by an inciting event and result from uninhibited excitation and/or decreased inhibition of a pool of neurons. If physiologic seizure abortive mechanisms fail, the ensuing unrestrained synchronization of neurons-status epilepticus-can be life-threatening and is associated with the potential for marked morbidity in survivors and high medical care costs. Prognosis is intimately related to etiology and its response to therapeutic measures. Timely implementation of pharmacologic therapy while concurrently performing a stepwise workup for etiology are paramount. Neurodiagnostic testing should guide titration of pharmacologic therapies, and help determine if there is a role for immune modulation.

Discovering themes in medical records of patients with psychogenic non-epileptic seizures

Introduction

Epileptic and psychogenic non-epileptic seizures (PNES) are common diagnostic problems encountered in hospital practice. This study explores the use of unsupervised machine learning in discovering themes in medical records of patients presenting with PNES. We hypothesised that themes generated by machine learning are comparable with the classification by human experts.

Methods

This is a retrospective analysis of the medical records in the emergency department of patients (age >18 years) with PNES who underwent inpatient video-electroencephalography monitoring from May 2009 to June 2014 and received a final diagnosis of PNES. Prior to machine learning of written text, we applied a standardised approach in natural language processing to create a document-term matrix (removal of numbers, stop-words and punctuations, transforming fonts to lower case). The words were separated into tokens and treated as if existing within a bag-of-words. A probability of each word existing within a topic (theme) was modelled on multivariate Dirichlet distribution (R Foundation, V.3.5.0). Next, we asked four experts to independently provide a clinical interpretation of the generated topics. When the majority of (≥3) experts agreed, it was regarded as highly congruent. Interactive data are available on the web at (https://gntem2.github.io/PNES/%23topic=1&lambda=0.6&term=).

Results

There were 39 patients (74.4% women, median age 35 years with range 20-82). A total of 121 documents were converted to text files for text mining. There were 15 generated topics with 12/15 topics rated as highly congruent. The main themes were about descriptors of seizures and medication use.

Conclusions

The findings from machine learning on PNES-related documentation provides evidence for the feasibility of applying machine-learning methodology to analyse large volumes of medical records. The topics generated by machine learning were congruent with interpretations by clinicians indicating this method can be used for screening of medical conditions among large volumes of medical records.

Clinical differentiation of psychogenic non-epileptic seizure: a practical diagnostic approach

Background

Psychogenic non-epileptic seizure (PNES) has long been the counterpart of epileptic seizure (ES). Despite ample of evidence differentiating the two, PNES mistakenly diagnosed as ES was still common, resulting in unnecessary exposure to long-term antiepileptic medications and reduced patient’s and caregiver’s quality of life, not to mention the burgeoning financial costs.

Objectives

In this review, we aimed to elucidate various differences between PNES and epileptic seizure with respect to baseline characteristics, seizure semiology, EEG pattern, and other key hallmark features.

Methods

An unstructured search was carried out in PubMed, MEDLINE, and EMBASE using keywords pertinent to PNES and ES differentiation. Relevant information was subsequently summarized herein.

Results

PNES differs significantly with ES in terms of baseline characteristics, prodromal symptoms, seizure semiology, presence of pseudosleep, and other hallmark features (for instance provoking seizure with suggestion). The combined approach, if applied appropriately, can yield high diagnostic yield.

Conclusions

PNES can be clearly differentiated from ES via careful adherence to a set of valid clinical cues. The summarized clinical hallmarks is highly useful to prevent unnecessary ES diagnosis and treatment with AEDs.

Can seizure-related heart rate differentiate epileptic from psychogenic nonepileptic seizures?

OBJECTIVES

We aimed to (1) determine if seizure-related heart rate (HR) differentiates epileptic seizures (ES) from psychogenic nonepileptic seizures (PNES); (2) define the most useful point of the following HR measurements: preictal, ictal-onset, maximal-ictal, or postictal; and (3) delineate the optimal HR cutoff points (absolute HR and relative HR increase) to differentiate ES from PNES.

METHODS

All video-electroencephalography (VEEG) recorded at an Australian tertiary hospital from May 2009 to November 2015 were retrospectively reviewed. Baseline (during rest and wakefulness), 1-min preictal, ictal-onset, maximal-ictal, and 1-min postictal HR were measured for each ES and PNES event. Events lasting <10 s or with uninterpretable electrocardiogram (ECG) due to artifacts were excluded. Receiver operating characteristic curve analysis was performed to assess the diagnostic accuracy of HR reflected by the area under the curve (AUC).

RESULTS

Video-electroencephalography of 341 ES and 265 PNES from 130 patients were analyzed. The AUC for preictal, ictal-onset, maximal-ictal, and postictal HR were found to have poor differentiation between all types of ES and PNES. However, comparing bilateral tonic-clonic ES and PNES, AUC for absolute maximal-ictal HR was 0.84 (95% confidence interval [CI]: 0.73-0.95) and for absolute postictal HR was 0.90 (95% CI: 0.81-1.00) indicating good diagnostic discrimination. Using Youden's index to diagnose tonic-clonic ES, the optimal cutoff point for absolute maximal-ictal HR was 114 bpm (sensitivity: 84%, specificity: 82%) and for absolute postictal HR was 90 bpm (sensitivity: 91%, specificity: 82%).

CONCLUSION

These findings suggest that seizure-related HR is useful in differentiating bilateral tonic-clonic ES from PNES. Based on the AUC, the best diagnostic measurements are maximal-ictal and postictal HR.

Atypical duration of epileptic and psychogenic nonepileptic events

OBJECTIVES

We aimed to estimate the frequency of epileptic seizures (ES) and psychogenic nonepileptic seizures (PNES) with atypical duration in our epilepsy monitoring unit (EMU), in order to raise awareness of atypical durations of both types of events.

MATERIALS & METHODS

We retrospectively reviewed all consecutive video-electroencephalogram (vEEG) recordings in our medical center's EMU from January 2013 to December 2017 and identified patients with seizures with atypical duration. Short PNES were defined as those lasting fewer than 2 min and long ES as those lasting for more than 5 min.

RESULTS

The files of 830 adult (age >16 years) patients were reviewed, of whom 26 patients (3.1%, mean age: 33.3 ± 9.8 years, 12 females) were diagnosed as having an unusual seizure duration. Among 432 patients with ES during monitoring, fourteen patients [3.2% (95% confidence interval (CI): 1.5%-5.0%), mean age: 33.0 ± 12.2, 5 females [had long ES durations (exceeding 5 min). In 64% of patients with long ES, the events were provoked by antiepileptic drug (AED) withdrawal during vEEG, 62% had focal lesion on brain imaging, and 64% had a frontotemporal or a temporal seizure focus. Among 223 patients diagnosed with PNES, 12 patients [5.4% (95% CI: 2.2%-8.6%), mean age: 33.6 ± 6.6, 7 females] had short PNES durations (less than 2 min) and demonstrated motor (9/12, 75%), altered responsiveness (6/12, 50%), and vocalization (5/12, 42%) as the most prominent clinical features.

CONCLUSIONS

The data from our case files highlight two main considerations in the diagnosis of paroxysmal events: prolonged event can be due to ES, while short events can be psychogenic.

The coexistence of psychogenic nonepileptic and epileptic seizures in the same patient is more frequent than expected: Is there any clinical feature for defining these patients?

OBJECTIVES

This study aimed to investigate the prevalence of psychogenic nonepileptic seizures (PNES) and PNES-epilepsy coexistence within all video-electroencephalography (EEG) monitoring unit (VEMU) referrals and to identify semiological and electrophysiological features to differentiate patients with PNES-epilepsy coexistence from PNES-only.

METHODS

We retrospectively reviewed medical files, VEMU reports, and videos of 1983 adult patients. Demographical, historical, clinical, neuroimaging, and electrophysiological parameters of all patients were recorded. We classified patients into five groups as definite PNES-only, definite PNES-epilepsy coexistence, definite PNES-probable epilepsy coexistence, probable PNES-definite epilepsy coexistence, and probable PNES-only. We defined a "definite" group when we saw the ictal EEG and/or video recording of the seizure. The "probable" term is used when there is strong evidence from the history of a particular seizure type and suggestive interictal EEGs without video recordings.

RESULTS

Two hundred and three of 1983 patients (10.23%) had PNES. Sixty-six of patients with PNES (32.51%) had definite PNES-epilepsy coexistence. When probable cases were included, the PNES-epilepsy coexistence ratio was 53.69% within all patients with PNES. The prevalence of PNES-epilepsy coexistence was 3.32% within all our VEMU referrals. Lower high school graduation rate, earlier age of disease onset, history of status epilepticus, febrile convulsion and brain surgery, use of three or more antiepileptic drugs, and abnormal magnetic resonance imaging (MRI) findings supported PNES-epilepsy coexistence (p < 0.05). On the contrary, seizure duration longer than 10 min was in favor of PNES-only (p < 0.05).

CONCLUSIONS

The prevalence of PNES-epilepsy coexistence might be more frequent in VEMUs than expected. Some demographic and semiological features and electrophysiological findings might be useful in differentiating patients with PNES-epilepsy coexistence from patients with PNES-only.

Plasma-lactate levels in simulated seizures - An observational study

PURPOSE

Differentiating between epileptic seizures, convulsive syncope or non-epileptic seizures is a common diagnostic challenge in the acute setting. Plasma-lactate levels have previously been proposed as a tool to aid in differentiating between epileptic and non-epileptic seizures, with lower levels of lactate suggesting a non-epileptic origin. The aim of this study was to investigate levels of lactate in non-epileptic seizures.

METHODS

Healthy subjects were asked to perform a simulated seizure lasting no more than 5 min. Venous blood samples were taken before and immediately after the simulated seizure and analyzed using an ABL90 FLEX yielding information about lactate, pH, pO2,pCO2, electrolytes and plasma glucose.

RESULTS

8 people participated in the study: 6 men and 2 women aged 27-45. The average pre-simulation lactate was 1.1 mmol/L while the average pH was 7.39. The average post-simulation lactate was 10.2 mmol/L while the average pH was 7.25. This means an average increase in plasma-lactate of 9.1 mmol/L and an average drop of 0.15 in pH.

CONCLUSION

Our data indicate that high rises in lactate levels are not specific for an epileptic origin. Further study of lactate as a marker for epileptic seizures is warrented.

Clinical Classifications of Children With Psychogenic Non-epileptic Seizure

Objective: To analyze the clinical features of children with psychogenic non-epileptic seizures in one tertiary center in China. Methods: Clinical data including medical records and video- electroencephalograph (video-EEG) monitoring records of 88 pediatric PNES patients hospitalized in the pediatric department of Xuanwu Hospital, Beijing, China from April, 2012 to April, 2018 were collected in this study. Demographic information of patients, semiological classification, duration, and frequency of symptoms, risk factors as well as comorbidity were summarized and analyzed. Results: For semiological classification, all PNES related symptoms were divided into different categories: motor symptoms, unresponsiveness, sensory symptoms, visceral symptoms, and abnormal behaviors, among which motor symptoms were the most prevalent form. Risk factors were reviewed and categorized into two groups: persistent factors and predisposing factors, and patients were most frequently affected by the influences of families. The duration and frequency of symptoms varied substantially within PNES patients while the average time of duration was relatively longer than epilepsy as reported previously. Epilepsy was considered as the most frequent comorbidity of PNES and PNES patients misdiagnosed as epilepsy often mistreated with antiseizure medication. Significance: Our study showed that motor PNES are the most frequent seizure type. Family issues were a risk factor for PNES. Epilepsy was the most frequent co-existing neurological comorbidity.

PNESSE 1: Psychogenic status and status epilepticus: Could they be distinguished retrospectively? A survey among neurologists

OBJECTIVE

The aim of this study was to evaluate neurologists' reliability in recognizing retrospectively a diagnosis of psychogenic status and status epilepticus (SE) based solely on clinical semiology, as reported in medical charts.

METHODS

This is a retrospective analysis of medical records of patients with suspected SE, diagnosed with psychogenic status and SE, proven by video-electroencephalography (EEG) monitoring, over a two-year period, from January 1st 2012 to December 31st 2013. Eight additional patients outside this time frame were included in this series because they had video-EEG proven psychogenic status, and they met all the inclusion criteria. The group with SE was divided into symptomatic SE (SSE) if a precipitating factor was identified, and undetermined SE (USE) if none were identified. Twenty-two neurologists from the CHU de Grenoble-Alpes were asked to fill out a survey where they were asked to score, for each patient, their agreement, using Likert scales, for the respective diagnoses of psychogenic status and SE. Their opinions were based on a provided written sheet summarizing the clinical description of the event and patients' clinical context. Neurologists were blinded to video-EEG monitoring results and final diagnosis. The level of agreement, disagreement, and the homogeneity of neurologist's responses according to the final diagnosis were then calculated. Finally, clinical data, as provided in the event's clinical description and context, considered as highly relevant by neurologists to establish an accurate diagnosis were gathered.

RESULTS

Eighteen neurologists completed the survey for 48 patients, including 11 diagnosed with psychogenic status and 37 with SE (30 with SSE and 7 with USE). For patients diagnosed with SE, the presence of a precipitating factor increased the likelihood and the homogeneity among neurologists of a diagnosis of SE (77%), with a specificity (Sp) of 96% and a positive predictive value of 95%. The lack of a precipitating factor significantly decreased the diagnosis likelihood of SE (55%) with a predictive value of 82%. For patients diagnosed with psychogenic status, most of neurologists agreed with the diagnosis of psychogenic status (69%) with a predictive value of 82%, although heterogeneity in the diagnosis was found. According to neurologists participating in this study, most significant terms, found in the medical charts, helping to distinguish SE from psychogenic status were "stereotypical movements", "limb myoclonus", "epilepsy", and "vigilance alteration". To differentiate psychogenic status from SE, most relevant terms used by neurologists were "resistance to eyes opening", "anarchic movements", "prolonged motor manifestations", "limb tremor" and "opisthotonus". However, analysis of the distribution of the terms among the different groups (SSE, USE, and psychogenic status) showed no significant difference.

SIGNIFICANCE

This study is in line with previous literature highlighting the difficulty in retrospectively differentiating SE from psychogenic status based on clinical events description recorded in the medical chart.

Semiological characteristics of patients with psychogenic nonepileptic seizures: Gender-related differences

Psychogenic nonepileptic seizures (PNES) are more prevalent among women, and diagnosis may sometimes be delayed by as much as seven years. Understanding the effect of gender on the presentation of a PNES may assist with diagnosis based on semiological details in the clinical setting. Although video-EEG monitoring (VEM) is the gold standard for diagnosing PNES, determining gender-related seizure semiology through careful history may prevent diagnostic delay while waiting for VEM. The aim of this study was to investigate gender-related differences in the semiology of PNES. Patients, all aged at least 16 years, diagnosed with PNES following VEM between December 2005 and November 2016 were included in this study. All patients' medical records and video-EEG-documented PNES were reviewed, and the presence or absence of semiological signs was recorded for each documented attack. Demographic features and semiological signs of PNES were compared between female and male patients. Forty-one patients (31 females, 10 males) aged 27.2 ± 12.2 years (range: 16-65) were included in the study. Mean age at onset of PNES was higher for female patients than males, at 24.3 ± 11.5 versus 17.5 ± 3.2 years (p = 0.005). The median duration of PNES was longer for female patients than males, at 10 min (range: 5 s-120 min) versus 2 min (range: 10 s-60 min) (p = 0.016). The most common symptom was forced eye closure in both genders. No significant gender-specific differences were observed in terms of the type or semiology of PNES. Although there are no major gender-related differences in PNES semiology, our findings highlight the importance of greater caution, especially in male patients, when diagnosing PNES, remembering that onset may also occur at young ages and that a short seizure duration does not exclude PNES.

Comparison of postictal semiology and behavior in psychogenic nonepileptic and epileptic seizures

BACKGROUND

The available information on postictal semiology and behavior in patients with psychogenic nonepileptic seizure (PNES) is limited. In this study, we explore the differences in postictal semiology and behavior between patients with epileptic seizure (ES) and PNES and focus on clinical features that may be helpful in differentiating these two conditions.

METHODS

In this retrospective study, video-electroencephalograph (video-EEG) of 144 seizures from 64 patients with PNES and 66 seizures from 42 patients with ES were reviewed. Three novel postictal behaviors were compared between the two groups: a) abrupt, brief, and rapid blinking or shaking of the head as if regaining sensorium or "coming out" of the ictal event; b) looking around the room with a scanning and uncertain look; c) posing a question of "what happened?" or a similar question to the others present in the room. In addition, differences in several other postictal characteristics were studied.

RESULTS

At least one of the three specific postictal behaviors was seen in 20.1% of patients with PNES but none of the patients with ES resulting in 100% specificity and 36% sensitivity. While mean ictal duration was significantly longer in patients with PNES (175.3 ± 168 s) compared to ES (105.4 ± 102.9 s), the interval between the end of ictal episode and first correct verbal response (74.5 ± 126.2 s versus 139.4 ± 185.4 s), or first followed command (84.1 ± 133.8 s versus 141.1 ± 192.1 s) were shorter. In the group with PNES, 59.7% of patients demonstrated a whispering or altered voice during the first correct verbal response versus 21.2% of patients in the group with ES. The first followed command was slow or erroneous in 49.3% of the patients with PNES and in 19.7% of the patients with ES.

CONCLUSION

In this study, we found significant differences between postictal semiology and behavior of patients with PNES and ES that can be helpful tools in distinguishing between these two conditions. Specifically, three novel postictal behaviors were studied and were found to have a high specificity, but low sensitivity, in distinguishing PNES from ES.

[Psychogenic non epileptic seizures : Differential diagnostic features]

Psychogenic nonepileptic seizures (PNES) are to be considered in the differential diagnosis of a transient loss of consciousness. Their discrimination from syncope, epileptic seizures or vascular events can be difficult and requires profound knowledge about the semiology and clinical presentation of PNES and their differential diagnoses. Erroneous diagnoses and the resulting therapies lead to elevated morbidity, elevated costs and a poorer outcome. The aim of the present article is to provide an overview on PNES and their delineation from the clinical pictures of epilepsy and syncope.