Coraline Hingray

Clinical classification of psychogenic non-epileptic seizures based on video-EEG analysis and automatic clustering

Background Psychogenic non-epileptic seizures (PNES) or attacks consist of paroxysmal behavioural changes that resemble an epileptic seizure but are not associated with electrophysiological epileptic changes. They are caused by a psychopathological process and are primarily diagnosed on history and video-EEG. Clinical presentation comprises a wide range of symptoms and signs, which are individually neither totally specific nor sensitive, making positive diagnosis of PNES difficult. Consequently, PNES are often misdiagnosed as epilepsy. The aim of this study was to identify homogeneous groups of PNES based on specific combinations of clinical signs with a view to improving timely diagnosis. Methods The authors first retrospectively analysed 22 clinical signs of 145 PNES recorded by video-EEG in 52 patients and then conducted a multiple correspondence analysis and hierarchical cluster analysis. Results Five clusters of signs were identified and named according to their main clinical features: dystonic attack with primitive gestural activity (31.6%); pauci-kinetic attack with preserved responsiveness (23.4%); pseudosyncope (16.9%); hyperkinetic prolonged attack with hyperventilation and auras (11.7%); axial dystonic prolonged attack (16.4%). When several attacks were recorded in the same patient, they were automatically classified in the same subtype in 61.5% of patients. Conclusion This study proposes an objective clinical classification of PNES based on automatic clustering of clinical signs observed on video-EEG. It also suggests that PNES are stereotyped in the same patient. Application of these findings could help provide an objective diagnosis of patients with PNES.

Access to diagnostic and therapeutic facilities for psychogenic nonepileptic seizures: An international survey by the ILAE PNES Task Force

Studies from a small number of countries suggest that patients with psychogenic nonepileptic seizures (PNES) have limited access to diagnostic and treatment services. The PNES Task Force of the International League Against Epilepsy (ILAE) carried out 2 surveys to explore the diagnosis and treatment of PNES around the world.

Psychogenic non-epileptic seizures (PNES)

Psychogenic non-epileptic seizures (PNES) are defined as change in behavior or consciousness resembling epileptic seizures but which have a psychological origin. PNES are categorized as a manifestation of dissociative or somatoform (conversion) disorders. Video-EEG recording of an event is the gold standard for diagnosis. PNES represent a symptom, not the underlying disease and the mechanism of dissociation is pivotal in the pathophysiology. Predisposing, precipitating and perpetuating factors should be carefully assessed on a case-by-case basis. The process of communicating the diagnosis using a multidisciplinary approach is an important and effective therapeutic step.

Les comorbidités psychiatriques dans l’épilepsie

Psychiatric comorbidities are overrepresented in people suffering from epilepsy in comparison to the general population. There is a two-way link between epilepsy and psychiatric disorders. Psychiatric symptomatology is specific in epilepsy, according to the chronology of symptoms in relation to the seizure (inter, pre- or postictal). Easy to use, fast and efficient self-administered questionnaires are available to evaluate depressive (NDDI-E) and generalized anxiety disorder (GAD-7) symptoms. Selective serotonin reuptake inhibitors (SSRIs) are not proconvulsant and can be safely used to treat depressive or anxious disorders.

Pitfalls in the diagnosis of new-onset frontal lobe seizures

We reported the case of a young woman who received an antiepileptic drug after a first possible generalized tonic-clonic seizure with no clear inter-ictal epileptic paroxysms in the routine electroencephalogram. Her stereotypical movements decreased but did not disappear with treatment. Then a diagnosis of PNES was considered by neurologist after witnessing a stereotypical motor episode. While AED treatment was decreased and stopped, epileptic seizure frequency and severity increased with secondary generalized tonic-clonic seizures. Then she presented postictal psychotic features that combined with video-EEG findings led to the final diagnosis of new onset pre-frontal lobe epilepsy.

How can we identify psychiatric morbidity in patients with psychogenic nonepileptic seizures

In an interesting article, Magaudda et al. [1] explain that patients with mixed psychogenic nonepileptic seizures (PNES) and epilepsy are heterogeneous and can be divided into three groups based on a hypothesis concerning the etiological mechanisms in play. Identifying homogenous subgroups of patients in the large, heterogenous group of people with PNES is important, as it could provide a better understanding of PNES and help us to develop more specific treatments. Numerous previous studies have attempted to categorize patients with PNES on the basis of video/EEG analysis and automatic clustering [2], trauma history and levels of dissociation [3], psychiatric comorbidity or learning disability [4], and gender [5]. One of the most important methodological requirements in psychiatric research--indeed in all medical research fields--is to produce valid, reproducible data. But unfortunately, psychiatric clinical examination has been shown to perform poorly in terms of sensitivity and validity for research purposes [6] and [7]. Hence the current international standard is to use validated questionnaires to identify and describe psychiatric morbidity in both DSM-IV axis I (depression, schizophrenia, etc.) and DSM-IV axis II (personality disorders) [8] and [9]. In the field of PNES, associated or not associated with epilepsy, we also emphasize the need for strong interdisciplinary collaboration between neurology and psychiatry for diagnostic assessment, care, and follow-up of patients. It is regrettable that Dr. Magaudda does not mention any psychiatric intervention in the process of diagnosis and treatment of their patients, and that the study did not use a standardized psychiatric evaluation. Accordingly, we believe that this study does not meet the methodological requirements to support the interesting starting hypothesis, and will be difficult to replicate. Additional studies on this topic should be underpinned by close neurological and psychiatric collaboration and the use of validated questionnaires.

Crisi non epilettiche psicogene (CNEP)

Le crisi non epilettiche psicogene (CNEP) ricordano, come fenomeno, delle crisi epilettiche, ma hanno un’origine psicologica. Appartengono alla categoria dei disturbi dissociativi/conversioni nelle classificazioni internazionali. La diagnosi di certezza e fornita dalla registrazione videoelettroencefalografica (EEG) delle manifestazioni cliniche. I molti pazienti che soffrono di CNEP, donne in tre quarti dei casi, formano un’entita eterogenea. L’esistenza di una psicopatologia specifica, tuttavia, deve far ritenere la diagnosi di CNEP una diagnosi positiva e non una diagnosi di esclusione. La presentazione clinica dei disturbi e oggetto di classificazioni basate sulla presenza simultanea di sintomi elementari raggruppati in cluster. Si osserva, nella maggior parte dei casi, una dissociazione psichica di origine traumatica. I progressi nello studio della neurobiologia delle emozioni permettono una migliore comprensione dei legami che uniscono CNEP e dissociazione e chiariscono le modalita di valutazione del disturbo e la gestione terapeutica. I fattori di rischio, le cause e le modalita di insorgenza delle CNEP sono, ormai, modellizzati a partire dall’interazione tra fattori predisponenti, precipitanti e perpetuanti all’interno di modelli multilivello. E, ormai, possibile suggerire la diagnosi di CNEP prima della realizzazione della video-EEG dopo un’analisi standardizzata dell’insieme delle comorbilita psichiatriche. L’annuncio adattato alla diagnosi, la valutazione multidisciplinare del disturbo, la psicoeducazione e le terapie comportamentali permettono un trattamento efficace delle CNEP, a condizione di porre una diagnosi precoce e di agire rapidamente.

Early Withdrawal Effects in a Heavy Cannabis Smoker During Hemodialysis

After years of debate about its relevance, cannabis withdrawal syndrome has been recently added to the fifth version of the Diagnostic and Statistical Manual of Mental Disorders (1). This syndrome appears classically within 24 hours after cannabis cessation, peaks between days 2 and 6, and may last for 1 to 2 weeks (2). It affects 55% to 89% of regular cannabis users (2). The cannabis withdrawal syndrome is clinically defined by irritability/anger, nervousness/anxiety, sleep difficulties, decreased appetite or weight loss, restlessness, depressed mood, or several physical symptoms such as abdominal pain, shakiness, or sweating (1). Evidence of cannabis withdrawal syndrome is based on behavioral observations in animal studies (3), clinical observation in patients (4), or epidemiological surveys (5). However, the biological correlates of this phenomenon remain unclear, challenging the validity of the syndrome. This lack of knowledge is partially explained by the interindividual variability of delta 9-tetrahydrocannabinol (THC) metabolism (6) and the complexity of exchanges between plasma and tissues (7). Here, we present a clinical case where hemodialysis sessions brought on cannabis withdrawal in a heavy cannabis smoker. Whole blood assays of THC and its metabolites in these specific conditions offered a relevant biological marker for cannabis withdrawal and confirmed the existence of the syndrome.