Impact of antiseizure medication with a very long half-life on long term video-EEG monitoring in focal epilepsy.

PURPOSE: To assess the impact of antiseizure medications (ASMs) with a very long half-life on long term video-EEG monitoring (LTM) in people with focal epilepsy (FE). METHODS: In this retrospective cohort study, we searched our local database for people with FE who underwent ASM reduction during LTM at the University Hospital of 'La Fe', Valencia, from January 2013 to December 2019. Taking into account the half-life of the ASM, people with FE were divided into two groups: Group A contained individuals who were taking at least one ASM with a very long half-life at admission, and Group B consisted of those not taking very long half-life ASMs. Using multivariable analysis to control for important confounders, we compared the following outcomes between both groups: seizure rates per day, time to first seizure, and LTM duration. RESULTS: Three hundred seventy individuals were included in the study (154 in Group A and 216 in Group B). The median recorded seizure rates (1.3 seizures/day, range 0-15.3 vs.1.3 seizures/day, range 0-9.3, p-value=0.68), median time to the first seizure (24 h, range 2-119 vs. 24 h, range 2-100, p-value=0.92), and median LTM duration (4 days, range 2-5 vs. 4 days, range 2-5, p-value=0.94) were similar in both groups. Multivariable analysis did not reveal any significant differences in the three outcomes between the two groups (all p-values>0.05). CONCLUSION: ASMs with a very long half-life taken as co-medication do not significantly affect important LTM outcomes, including recorded seizure rates, time to the first seizure, or LTM duration. Therefore, in general, there is no need to discontinue ASMs with a very long half-life prior to LTM.

Drug load and memory during intracarotid amobarbital procedure in epilepsy.

BACKGROUND: Anti-seizure medications (ASMs) have been related to poor cognitive function, but their relationship with intracarotid amobarbital procedure (IAP) results remains unclear. AIMS OF THE STUDY: To elucidate whether the number and drug load of ASMs are associated with memory scores of the IAP and the neuropsychological assessment. METHODS: Fifty-nine adult patients with drug-resistant epilepsy (mean age = 36.1, SD = 11.6) underwent bilateral IAP (with drawings and words as memory items) and a neuropsychological assessment to assess the risk of post-surgical memory decline. Total ASM drug load was calculated by summing the daily dose/defined daily dose ratio of every ASM of each patient. Pearson's correlations and hierarchical regressions were computed. RESULTS: Total IAP memory score was associated with total ASM drug load (r = -0.30, p = 0.02) and seizure frequency (r = -0.25, p = 0.05). After controlling clinical variables, total ASM drug load explained 16% of the variance of total IAP memory score. This relationship was especially prominent in patients with left hemisphere focus (r = -0.33, p = 0.04). The number of current ASMs was not related to IAP memory score (r = -0.16, p = 0.24). The number or drug load of ASMs were not related to neuropsychological assessment results (for all, p > 0.07). CONCLUSIONS: Our findings suggest that total drug load can be a confounding variable in the IAP memory performance that could explain, at least in part, the reverse asymmetries reported in different studies.

Epilepsy surgery beyond 50 years: Long-term seizure and cognitive outcomes.

INTRODUCTION: Surgery is a well-demonstrated effective treatment for patients with refractory epilepsy. However, there are scarce data about the efficacy in older patients. Endpoint was to evaluate the outcome of epilepsy surgery in pharmacorresistant patients operated in middle-late adulthood. METHODS: We conducted a retrospective observational study including patients who underwent a epilepsy surgery at age ≥ 50. Presurgical clinical data, type of surgery, and postsurgical seizure outcome and neurological complications, including neuropsychological assessment were analyzed. Minimum post-surgical follow-up was 1 year. RESULTS: We identified 38 patients (22 males, 17 females) out of 350 patients who underwent a resective surgery with curative intention in our Epilepsy Unit (12%). Median age at surgery was 56 years (50-69), with median epilepsy duration of 42 years (4-67). Neuroimaging showed focal epileptogenic lesions in 37 patients, mainly mesial temporal sclerosis (21). Presurgical neuropsychological evaluation was available in 38 patients: 35 had deficits, mostly in verbal or visual memory. Twenty-eight patients underwent standard temporal lobectomy with amygdalohippocampectomy, 7 lesionectomy and 4 lobectomy. Median follow-up was 4.46 years (1-9.75). A good outcome was achieved by 86.8% (28 Engel I; 5 Engel II); 5 patients were studied with SEEG, without any complications. None had postsurgical permanent neurological complications. From 22 patients with available post-surgical neuropsychological assessment, 16 scored lower than in pre-surgical one, mainly in memory domain. CONCLUSION: Surgical treatment of long-term refractory epilepsy in patients ≥50 years can be effective and safe. Post-surgical memory decline is a frequent side effect, but with a low impact in daily life.

Desafíos diagnósticos en epilepsia / Diagnostic challenges in epilepsy

Introducción. Las crisis epilépticas y la epilepsia son parte de la práctica clínica diaria en neurología. No obstante, el número de diagnósticos falsos positivos es sorprendentemente alto. Casi uno de cada cinco pacientes tratado por epilepsia en realidad no tiene ese diagnóstico, un porcentaje elevado teniendo en cuenta las consecuencias sociomédicas que conlleva el diagnóstico de epilepsia. Objetivos. Resumir los desafíos diagnósticos más importantes en epilepsia, describir posibles fuentes de error en el diagnóstico y proporcionar consejos sobre cómo evitarlos. Desarrollo. La epilepsia se caracteriza por una tendencia a sufrir crisis epilépticas no provocadas. El mayor obstáculo al diagnosticar una epilepsia radica en que las crisis epilépticas son fenómenos transitorios que ocurren relativamente con poca frecuencia y el médico que realiza el diagnóstico raramente llega a verlas. Además, existen otros eventos clínicos, como por ejemplo síncopes o crisis no epilépticas, que pueden tener una apariencia similar a las crisis epilépticas y, en consecuencia, confundirse con ellas. Finalmente, al interpretar las dos técnicas diagnósticas complementarias más importantes en epileptología, el electroencefalograma y la resonancia magnética cerebral, deben tenerse en cuenta los errores más comunes para prevenir diagnósticos erróneos. Conclusiones. El diagnóstico de una epilepsia es un reto y debe basarse en una historia clínica detallada y específica. Si desde el inicio existen dudas razonables sobre el diagnóstico de epilepsia o si el paciente no responde bien al tratamiento antiepiléptico, recomendamos derivar al paciente a un centro especializado que establezca un diagnóstico definitivo

Introduction. Epileptic seizures and epilepsy are part of daily clinical practice in neurology. Yet, the number of false positive diagnoses is surprisingly high. Almost one out of every five patients treated for epilepsy does not really have this diagnosis, which is a high percentage bearing in mind the social and medical consequences that being diagnosed with epilepsy entails. Aims. To summarise the most important diagnostic challenges in epilepsy, to describe possible sources of diagnostic error and to offer advice on how to avoid them. Development. Epilepsy is characterised by a tendency to suffer unprovoked epileptic seizures. The greatest obstacle when it comes to diagnosing a case of epilepsy is the fact that epileptic seizures are transient phenomena that occur relatively infrequently and the physician who must carry out the diagnosis will rarely see them. Moreover, there are other clinical events, such as syncopes or non-epileptic seizures, that may be similar to epileptic seizures in appearance and, consequently, can be mistaken for them. Finally, when interpreting the two most important complementary diagnostic techniques in epileptology, the electroencephalogram and magnetic resonance imaging of the brain, the most common errors must be taken into account in order to prevent mistaken diagnoses. Conclusions. The diagnosis of epilepsy is a challenge and must be based on a detailed and specific medical record. If there are any reasonable doubts, from the outset, about the diagnosis of epilepsy or if the patient does not respond well to the antiepileptic treatment, we recommend referring the patient to a specialised centre to establish a definitive diagnosis

Antiepileptic drug reduction and increased risk of stimulation-evoked focal to bilateral tonic-clonic seizure during cortical stimulation in patients with focal epilepsy.

INTRODUCTION: Stimulation-evoked focal to bilateral tonic-clonic seizure (FBTCS) can be a stressful and possibly harmful adverse event for patients during cortical stimulation (CS). We evaluated if drug load reduction of antiepileptic drugs (AEDs) during CS increases the risk of stimulation-evoked FBTCS. MATERIAL AND METHODS: In this retrospective cohort study, we searched our local database for patients with drug-resistant epilepsy who underwent invasive video-EEG monitoring and CS in the University Hospital la Fe Valencia from January 2006 to November 2016. The AED drug load was calculated with the defined daily dose. We applied a uni- and multivariate logistic regression model to estimate the risk of stimulation-evoked FBTCS and evaluate possible influencing factors. Furthermore, we compared patients whose AEDs were completely withdrawn with those whose AEDs were not. RESULTS: Fifty-eight patients met the inclusion criteria and were included in the analysis. Stimulating 3806 electrode contact pairs, 152 seizures were evoked in 28 patients (48.3%). Ten seizures (6.6%) in seven patients (12.1%) evolved to FBTCS. In the univariate and multivariate analysis, a 10% reduction in drug load was associated with an increase of the odds ratio (OR) of stimulation-evoked FBTCS by 1.9 (95%-CI 1.2, 4.0, p-value=0.04) and 1.9 (95%-CI 1.2, 4.6, p-value=0.04), respectively. In patients, whose AEDs were completely withdrawn the OR of FBTCS increased by 9.1 (95%CI 1.7, 69.9, p-value=0.01) compared with patients whose AEDs were not completely withdrawn. No other factor (implantation type, maximum stimulus intensity, number of stimulated contacts, history of FBTCS, age, gender, or epilepsy type) appears to have a significant effect on the risk of stimulation-evoked FBTCS. CONCLUSIONS: The overall risk of stimulation-evoked FBTCS during CS is relatively low. However, a stronger reduction and, especially, a complete withdrawal of AEDs are associated with an increased risk of stimulation-evoked FBTCS.

Painless diabetic motor neuropathy: a variant of diabetic lumbosacral radiculoplexus Neuropathy?

OBJECTIVE: Occasionally, diabetic patients develop painless, lower-limb, motor predominant neuropathy. Whether this is a variant of diabetic lumbosacral radiculoplexus neuropathy (DLRPN) (a painful disorder from ischemic injury and microvasculitis), a variant of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) or another disorder is unsettled. Here, we characterize the clinical and pathological features of painless diabetic motor predominant neuropathy. METHODS: We identified patients with this syndrome who underwent nerve biopsy. We compared pathological features to 33 DLRPN and 25 CIDP biopsies. RESULTS: 23 patients were identified (22 had type 2 diabetes mellitus); 12 men; median age 62.2 years (range 36-78); median weight loss 30 pounds (range 0-100). Overall, the clinical features were similar to DLRPN except painless patients had more symmetrical and upper limb involvement, with slower progression and more severe impairment. Physiological testing demonstrated pan-modality sensory loss, autonomic abnormalities and axonal polyradiculoneuropathies. Nerve biopsies were similar to DLPRN showing ischemic injury (multifocal fiber loss [11/23], perineural thickening [18/23], injury neuroma [11/23], neovascularization [17/23]) and evidence of altered immunity and microvasculitis (epineurial perivascular inflammation [23/23], prior bleeding [11/23], vessel wall inflammation [15/23], and microvasculitis [3/23]). In contrast, CIDP biopsies did not show ischemic injury or microvasculitis but revealed demyelination and onion-bulbs. INTERPRETATION: 1) Painless diabetic motor neuropathy is painless DLRPN and not CIDP and is caused by ischemic injury and microvasculitis. 2) The clinical features of painless DLRPN are different from typical DLPRN being more insidious and symmetrical with slower evolution. 3) The slower evolution may explain the lack of pain.

Antibodies to myelin-associated glycoprotein (anti-Mag) in IgM amyloidosis may influence expression of neuropathy in rare patients.

We have examined whether antibodies to myelin-associated glycoprotein (anti-MAG) influence neuropathy occurrence and phenotype in primary (AL IgM) amyloidosis. Anti-MAG and the cross-reacted sulfoglucuronyl paragloboside antibodies (SGPG) were studied in 46 patients with IgM amyloidosis (21 with polyneuropathy), and 21 matched IgM MGUS (monoclonal gammopathies of undetermined significance) controls without neuropathy. We assessed the occurrence, phenotype of neuropathy, and attributes of nerve conduction and their relation to antibody activity. Twenty of 46 patients with IgM amyloidosis (7 with and 13 without polyneuropathy) had elevation of anti-MAG or SGPG by enzyme-linked immunosorbent assay (ELISA). Two of the polyneuropathy patients with IgM amyloidosis had antibodies to MAG based on Western blot (WB) positivity. One of these patients, with the highest anti-MAG titer, had a painful sensory ataxia, with prominent demyelination, and amyloid deposition in sural nerve. The other anti-MAG WB-positive amyloid patient had an axonal neuropathy and dysautonomia. Low levels of anti-MAG antibodies were found in 12 of 21 IgM MGUS controls without neuropathy (mean follow-up, 11 years). We conclude that finding serum anti-MAG antibodies does not exclude the diagnosis of primary amyloidosis. They do not appear to affect the occurrence or expression of polyneuropathy, except possibly in occasional cases with WB positivity.