Non-convulsive status epilepticus: mimics and chameleons

Recurrent catamenial absence status epilepticus persisting in post-menopausal period: The pivotal role of video-EEG

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Diagnosing epileptic seizures in patients with Alzheimer's disease and deciding on the appropriate treatment plan

INTRODUCTION

Alzheimer's disease (AD) is the predominant cause of dementia and a significant contributor to morbidity among the elderly. Patients diagnosed with AD face an increased risk of epileptic seizures.

AREAS COVERED

Herein, the authors review the challenges in the diagnosis of seizures in patients with AD, the risks of seizures related to medications used in AD and the pharmacological treatment of seizures in AD. The authors also provide the reader with their expert opinion on the subject matter and future perspectives.

EXPERT OPINION

Healthcare professionals should maintain a vigilant approach to suspecting seizures in AD patients. Acute symptomatic seizures triggered by metabolic disturbances, infections, toxins, or drug-related factors often have a low risk of recurrence. In such cases, addressing the underlying cause may suffice without initiating antiseizure medications (ASMs). However, unprovoked seizures in certain AD patients carry a higher risk of recurrence over time, warranting the use of ASMs. Although data is limited, both lamotrigine and levetiracetam appear to be reasonable choices for controlling seizures in elderly AD patients. Decisions should be informed by the best available evidence, the treating physician's clinical experience, and the patient's preferences.

Case Report: Non-convulsive seizure following traumatic brain injury - a significant occurrence that needs to be considered due to potential long-term sequelae

Introduction/background

Non convulsive seizures (NCS) following traumatic brain injury (TBI) may remain undiagnosed due to lack of overt clinical manifestation and can have long-term sequelae due to delay in timely treatment. Occurrence of early NCS is known to have subsequent neurologic sequelae due to excitotoxic neuronal injury.

Case report

This is a case report of a young girl who sustained a TBI due to a motor vehicle accident (MVA) and was admitted with a fluctuating level of consciousness. Her clinical presentation was attributed to TBI; however as her conscious level did not recover, an electroencephalogram (EEG) was requested, which detected non convulsive status epilepticus (NCSE). Anti-seizure medication (ASM) was started. Her follow-up EEG and magnetic resonance imaging (MRI) were suggestive of the potential adverse effects of prolonged NCSE.

Conclusion

NCS may remain undiagnosed in TBI due to a paucity of overt clinical manifestations. Every patient with TBI and altered consciousness at presentation should be evaluated by continuous EEG monitoring immediately, if possible, in the emergency department to avoid long-term sequelae of NCS in such cases.

Nonconvulsive Status Epilepticus: A Review for Emergency Clinicians

BACKGROUND

Status epilepticus is associated with significant morbidity and mortality and is divided into convulsive status epilepticus and nonconvulsive status epilepticus (NCSE).

OBJECTIVE

This review provides a focused evaluation of NCSE for emergency clinicians.

DISCUSSION

NCSE is a form of status epilepticus presenting with prolonged seizure activity. This disease is underdiagnosed, as it presents with nonspecific signs and symptoms, most commonly change in mental status without overt convulsive motor activity. Causes include epilepsy, cerebral pathology or injury, any systemic insult such as infection, and drugs or toxins. Mortality is primarily related to the underlying condition. Patients most commonly present with altered mental status, but other signs and symptoms include abnormal ocular movements and automatisms such as lip smacking or subtle motor twitches in the face or extremities. The diagnosis is divided into electrographic and electroclinical, and although electroencephalogram (EEG) is recommended for definitive diagnosis, emergency clinicians should consider this disease in patients with prolonged postictal state after a seizure with no improvement in mental status, altered mental status with acute cerebral pathology (e.g., stroke, hypoxic brain injury), and unexplained altered mental status. Assessment includes laboratory evaluation and neuroimaging with EEG. Management includes treating life-threatening conditions, including compromise of the airway, hypoglycemia, hyponatremia, and hypo- or hyperthermia, followed by rapid cessation of the seizure activity with benzodiazepines and other antiseizure medications.

CONCLUSIONS

An understanding of the presentation and management of NCSE can assist emergency clinicians in the care of these patients.

Indications for the use of intravenous second-line antiseizure medications in an emergency room setting

BACKGROUND

Second-line iv antiseizure medications (ASMs) are used to treat status epilepticus (SE), but in the emergency room setting, there might be other intended and unintended indications for administration. We wanted to explore these different indications and assess the actual usage of first- and second-line ASMs for SE with reference to other uses, such as for SE mimics.

METHODS

In this retrospective study, we searched the electronic patient registry with the following terms: "epilepsy", "SE", and "seizure", during 2015. Patients at least 16 years old and treated with iv second-line ASMs were further analysed. We reassessed the indications for the use of iv ASMs based on clinical features and examinations performed.

RESULTS

A total of 166 episodes from 136 patients with a median age of 66 years were evaluated, constituting the following indication categories: ongoing SE (48.2%), recurrent seizures (19.3%), postictal (12.1%), seizure mimics (10.2%) and prophylactic use of ASMs (10.2%). Ongoing SE included the following subgroups: convulsive SE, focal aware SE, nonconvulsive SE (NCSE) and NCSE with coma. The seizure mimics group had a preexisting epilepsy diagnosis more often than the ongoing SE group (73% vs. 44%, p = 0.039). Ischaemic stroke was the most frequent seizure mimic. EEG was performed during hospital admission in 78% of patients with ongoing SE, 50% of patients with recurrent seizures, 75% of patients with postictal state, 53% of seizure mimic episodes and 12% of the prophylactic group. In NCSE and comatose NCSE, the diagnosis was made, and treatment was initiated only after an EEG in 52% and 30% of cases, respectively. The use of newer second-line ASMs (levetiracetam and lacosamide) was frequent in our study population. Immediate side effects of ASMs were infrequent.

CONCLUSIONS

Even though most of the use of ASMs was justified and administered for SE, it is a diagnostic challenge where a prior diagnosis of epilepsy can be a misleading factor, and EEG is an essential tool when clinical features are often overlapping with other acute seizure disorders. Side effects of the newer second-line ASMs after a single dose are infrequent.

Nonconvulsive status epilepticus in neurocritical care: A critical reappraisal of outcome prediction scores

OBJECTIVE

Nonconvulsive status epilepticus (NCSE) is a frequent condition in the neurocritical care unit (NCCU) patient population, with high morbidity and mortality. We aimed to assess the validity of available outcome prediction scores for prognostication in an NCCU patient population in relation to their admission reason (NCSE vs. non-NCSE related).

METHODS

All 196 consecutive patients diagnosed with NCSE during the NCCU stay between January 2010 and December 2020 were included. Demographics, Simplified Acute Physiology Score II (SAPS II), NCSE characteristics, and in-hospital and 3-month outcome were extracted from the electronic charts. Status Epilepticus Severity Score (STESS), Epidemiology-Based Mortality Score in Status Epilepticus (EMSE), and encephalitis, NCSE, diazepam resistance, imaging features, and tracheal intubation score (END-IT) were evaluated as previously described. Univariable and multivariable analysis and comparison of sensitivity/specificity/positive and negative predictive values/accuracy were performed.

RESULTS

A total of 30.1% died during the hospital stay, and 63.5% of survivors did not achieve favorable outcome at 3 months after onset of NCSE. Patients admitted primarily due to NCSE had longer NCSE duration and were more likely to be intubated at diagnosis. The receiver operating characteristic (ROC) for SAPS II, EMSE, and STESS when predicting mortality was between .683 and .762. The ROC for SAPS II, EMSE, STESS, and END-IT when predicting 3-month outcome was between .649 and .710. The accuracy in predicting mortality/outcome was low, when considering both proposed cutoffs and optimized cutoffs (estimated using the Youden Index) as well as when adjusting for admission reason.

SIGNIFICANCE

The scores EMSE, STESS, and END-IT perform poorly when predicting outcome of patients with NCSE in an NCCU environment. They should be interpreted cautiously and only in conjunction with other clinical data in this particular patient group.

Non-convulsive status epilepticus in Sotos syndrome: rare first presentation in a rare syndrome

INTRODUCTION

Prior to illustration of the causative genetic mutation responsible for Sotos syndrome, diagnosis was based on clinical criteria. They include characteristic facial gestalt, developmental delay, and evidence of overgrowth, in addition to other minor features as cardiac &genitourinary congenital malformation, seizures, scoliosis, among other features. Non-convulsive status epilepticus (NCSE) was not previously reported among Sotos patients.

CASE SUMMARY

An eleven-years old boy, with developmental delay, characteristic facial & skeletal features presented to the emergency department with a two-hour episode of lapse of consciousness. Electroencephalogram (EEG) showed fluctuating generalized spike-wave/poly-spike wave discharge <2.5 Hertz (Hz), lasting throughout the duration of recording. Intravenous (IV) levetiracetam was associated with clinical & EEG improvement & accordingly the patient was diagnosed as NCSE. The mother reported history of polyhydramnios, febrile seizure & developmental delay. Through clinical & radiological assessment revealed generalized hypotonia, low intelligence quotient (IQ), congenital ureteric stricture & pulmonary hypertension, prominent retro-cerebellar cistern, in addition to scoliosis & facial features suggestive of Sotos Syndrome. Six months after presentation, the patient remained seizure free on levetiracetam monotherapy.

CONCLUSION

NCSE could occur in Sotos syndrome. In our case, the first reported case of NCSE in Sotos syndrome, the characteristic facial & skeletal findings initiated further work up with fulfillment of the criteria required for the clinical diagnosis of Sotos syndrome.

COVID-19 masquerading as a non-convulsive status epilepticus

Since the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), more and more atypical presentations of COVID-19 are being reported. Here, we present and discuss non-convulsive status epilepticus (NCSE) as presenting symptom of SARS-CoV-2 infection at the Emergency Department.

Dementia with non-convulsive seizures: a case report

Non-convulsive seizures (NCSs) are highly treatable, but appropriate management is usually delayed because of inaccurate diagnoses as a result of variable clinical presentations, including an altered mental state. It is difficult to detect NCSs in patients with dementia. We report a case of NCS superimposed on cognitive decline caused by Alzheimer’s dementia. The patient’s history was carefully recorded. An electroencephalogram was recorded with sphenoidal electrodes, which showed epileptiform discharges in the right mesial temporal lobe and focal, sharply contoured, slow wave activity in the left fronto-temporal area, suggesting an epileptic origin contributing to the patient’s cognitive decline. After treatment with antiepileptic drugs, the patient’s cognitive functioning gradually improved. An accurate diagnosis of NCS relies on performing a detailed inventory of a patient’s history, thorough physical and neurological examinations, and electroencephalogram recordings. In patients with cognitive decline, testing for NCS should always be included in the differential diagnosis of cognitive impairment, even in the case of dementia. Early administration of antiepileptic drug therapy is the mainstay treatment for reversing the condition and for preventing prolonged insults from neurological sequelae.

'Hand mechanogram' in epilepsia partialis continua

Epilepsia partialis continua manifests as low-frequency, rhythmic involuntary movements of a focal body part. We report a young man, HIV-positive and with syphilis, who developed right-hand epilepsia partialis continua associated with a small left-sided cortico-subcortical frontal lesion. A pen and paper test provided 'mechanographic' data on frequency, amplitude and rhythmicity of the hand movements, helping distinguish it from other causes of low-frequency repetitive hand movements.

Salzburg Criteria, A Useful Tool in Non-Convulsive Status Epilepticus Diagnosis: A Retrospective Study

Introduction. Non-convulsive status epilepticus (NCSE) has been traditionally a challenging electroencephalographic (EEG) diagnosis. For this reason, Salzburg consensus criteria (SCC) have been proposed to facilitate correct diagnosis. Methods. We retrospectively reanalyzed 41 cases referred to our department (from 2016 to 2018) under the suspicion of NCSE. In this study, we compared the original description (standard criteria) versus the updated description (SCC) of the same EEG. Results. Originally, 15 patients were diagnosed as NCSE (37%) and 26 patients as no NCSE (63%), using the standard criteria. Then, we analyzed EEGs according to the SCC, which led to the following results: 9 patients fulfilled the criteria for definite NCSE (22%), 20 patients were diagnosed as possible NCSE (49%) and 12 patients were diagnosed as no NCSE (29%). Subsequently, when we analyze the outcome of possible NCSE cases, we note that 50% of these patients presented mild-poor outcome (neurological deficits, deceased). Indeed, we observed worse outcomes in patients previously diagnosed as no NCSE and untreated, specifically post-anoxic cases. Conclusions. Salzburg criteria seem to be a useful tool to support NCSE diagnosis, introducing the category of possible NCSE. In our study, we observed that it contributes to improving the prognosis and management of the patients. However, more prospective studies are needed to demonstrate the accuracy of SCC.

Neurological symptoms and blood neurofilament light levels

Neurofilament light chain (NfL) is an incredibly specific marker of neuronal injury that is not specific for cause or location of the neuronal damage. NfL is increasingly considered as possible biomarker of disease activity in neurological conditions. Several works reviewed the utility of NfL in the different diseases. Nonetheless, NfL is a universal marker of neuronal damage, which interpretation spaces beyond the single disease. Because of this, the interpretation of NfL may benefit by also considering how neurological symptoms relate to its blood concentration. Here, we review how different neurological symptoms can be associated with blood NfL levels with a practical interpretation of it.

Status Epilepticus: Work-Up and Management in Adults

Status epilepticus is one of the most common neurological emergencies and is likely to have increasing prevalence in coming years given an aging "baby boomer" population in the United States. Because status epilepticus is associated with significant morbidity and mortality, identification and treatment are paramount. Care should be taken to exclude nonorganic mimics and infectious and metabolic causes. Status epilepticus can be classified into stages with associated recommendations for escalation in therapy, increasing from push-dose benzodiazepines to continuous anesthetic infusions and other nontraditional therapies. Concurrent electroencephalogram monitoring helps to identify, localize, and assess resolution of ictal patterns alongside antiseizure drug administration. A protocol is proposed for the management of status epilepticus in a step-wise fashion.

De novo Absence Status Epilepticus in a pediatric cohort: Electroclinical pattern in a multicenter Italian patients cohort

PURPOSE

Absence Status epilepticus (AS) is a form of Non Convulsive Status Epilepticus defined as a prolonged, generalized and non-convulsive seizure, with an altered content of consciousness. We aim to describe a group of healthy children, who presented recurrent and unprovoked de novo AS as the only manifestation of their epilepsy, with an excellent response to antiepileptic drugs.

METHOD

We retrospectively reviewed the electroclinical and genetic features of 13 pediatric patients, referring to our epilepsy centers from 2005 to 2019, on the following criteria: (1) regular psychomotor development, (2) one or more unprovoked AS as the only epileptic manifestation, (3) normal blood testing, (4) normal neuroimaging, (5) EEG recording, (6) available follow-up (1-14 years).

RESULTS

Patients are 7 females and 6 males, aged 7-22, with a mean age at AS onset of 9,3 years. All of them started an antiepileptic therapy, with an excellent response to Valproic Acid (VPA) or Ethosuximide (ETS). 5 patients did not start the therapy immediately after the first AS and they presented recurrent AS (from 2 to 4 episodes). 10 of them performed aCGH, karyotype, NGS panel or Whole Exome Sequencing.

CONCLUSIONS

We suggest that de novo AS may be a well-defined age-related and self-limited epilepsy syndrome, with a good prognosis and excellent response to therapy, but it comes with a high risk of relapsing if not adequately treated with antiepileptic drugs.

Identification of non-convulsive status epilepticus with bradylalia using arterial spin-labeling magnetic resonance imaging

Case

Non‐convulsive status epilepticus (NCSE) is among the differential diagnoses of decreased consciousness, but often presents a diagnostic challenge. A 65‐year‐old woman was admitted to our emergency department with bradylalia. No abnormal finding was detected by computed tomography or magnetic resonance imaging. Subsequently, acquired arterial spin‐labeling images showed hyperperfusion in the right hemisphere.

Outcome

After the examination, the patient began experiencing left hemifacial seizures, which were relieved by diazepam; however, she was still agitated. Ictal confusion due to NCSE was suspected. Electroencephalography revealed periodic, generalized epileptiform activities with brief seizures of facial muscles by intermittent photic stimulation. Another supportive case of NCSE detected by arterial spin‐labeling from a 56‐year‐old right‐handed man has also been presented.

Conclusion

Arterial spin‐labeling magnetic resonance perfusion imaging provides valuable information regarding cerebral perfusion status in NCSE patients in emergency/acute settings.