Nonconvulsive status epilepticus in adults - insights into the invisible

Cefepime-Induced Neurotoxicity Presenting with Nonconvulsive Status Epilepticus Admitted as a Stroke Alert

BACKGROUND Cefepime-induced neurotoxicity has been described in intensive care units (ICUs) and neuro ICU settings, occurring in patients started on cefepime for management of severe infections and sepsis. Most cases occur within 1 to 10 days after starting the drug. We publish a case that occurred on the general medical ward of a patient who had been on cefepime therapy for 4 weeks prior to admission. The aim of this study was to improve the knowledge of this serious condition to general internists as our patient was being managed on the general medical ward. CASE REPORT A 72-year-old female on prolonged intravenous antibiotics for sacral and pelvic osteomyelitis presented with acute encephalopathy and aphasia in the setting of an acute kidney injury. Due to the acute focal neurologic deficit, she was initially admitted as a stroke alert. After a negative magnetic resonance imaging (MRI) of the brain, an electroencephalogram (EEG) was pursued and showed nonconvulsive status epilepticus (NCSE). NCSE was likely a result of cefepime therapy in the setting of an acute kidney injury. CONCLUSIONS Cefepime-induced neurotoxicity should be suspected in any patient on cefepime therapy who develops acute changes in mental status, myoclonus, or evidence of seizures. Risk factors for the disease include older age, renal dysfunction, critical illness, and inappropriate dosing based upon renal function. A high index of suspicion is required and delays in diagnosis are common as there are frequently multiple possible causes for altered mental status in systemically ill patients requiring treatment with broad-spectrum antibiotics.

Acute visual impairment as a main presenting symptom of non-convulsive status epilepticus: a case report

Background

Nonconvulsive status epilepticus (NCSE) is a state of ongoing seizure activity without convulsions. The heterogeneous and subtle clinical features of NCSE make diagnosis and treatment challenging. Here, we report a patient with NCSE who showed a main presenting symptom of acute visual impairment, which is a rare and atypical clinical symptom of NCSE.

Case presentation

A 62-year-old man was admitted to the neurology department after complaining of an inability to see in the right eye for 2 days and progressive headache. He had a history of poststroke epilepsy and vascular dementia. Physical examination revealed right visual field hemianopia, visual neglect and cognitive impairment. T2 and diffusion-weighted magnetic resonance imaging showed high signal intensity in the left temporal, parietal and occipital lobes. Electroencephalography monitoring was performed, which found continuous sharp wave discharges, especially in the regions of the left temporal, parietal and occipital lobes. These findings were most consistent with the diagnosis of NCSE. Thus, a treatment of intravenous pumping of diazepam and an oral antiepileptic drug was added immediately. After that, the visual loss in the patient recovered quickly, and electroencephalography did not find epileptiform waves. On day 11, a follow-up MRI was performed, which showed that the abnormal signals of the left temporal, parietal and occipital lobes were markedly attenuated, and the patient returned to his premorbid state with a modified Rankin Scale score of 3.

Conclusions

Acute visual impairment can be seen in NCSE, and it can be reversed by administering effective antiepileptic treatment. Meanwhile, transient peri-ictal MRI abnormalities can be observed in NCSE.

Early Epileptiform Discharges and Clinical Signs Predict Nonconvulsive Status Epilepticus on Continuous EEG

BACKGROUND

Critical care continuous electroencephalography (CCEEG) represents the gold standard for detection of nonconvulsive status epilepticus (NCSE) in neurological critical care patients. It is unclear which findings on short-term routine EEG and which clinical parameters predict NCSE during subsequent CCEEG reliably. The aim of the present study was to assess the prognostic significance of changes within the first 30 min of EEG as well as of clinical parameters for the occurrence of NCSE during subsequent CCEEG.

METHODS

Systematic analysis of the first 30 min and the remaining segments of prospective CCEEG recordings according to the ACNS Standardized Critical Care EEG Terminology and according to recently proposed NCSE criteria as well as review of clinical parameters of 85 consecutive neurological critical care patients. Logistic regression and binary classification tests were used to determine the most useful parameters within the first 30 min of EEG predicting subsequent NCSE.

RESULTS

The presence of early sporadic epileptiform discharges (SED) and early rhythmic or periodic EEG patterns of "ictal-interictal uncertainty" (RPPIIIU) (OR 15.51, 95% CI 2.83-84.84, p = 0.002) and clinical signs of NCS (OR 18.43, 95% CI 2.06-164.62, p = 0.009) predicted NCSE on subsequent CCEEG. Various combinations of early SED, early RPPIIIU, and clinical signs of NCS showed sensitivities of 79-100%, specificities of 49-89%, and negative predictive values of 95-100% regarding the incidence of subsequent NCSE (p < 0.001).

CONCLUSIONS

Early SED and early RPPIIIU within the first 30 min of EEG as well as clinical signs of NCS predict the occurrence of NCSE during subsequent CCEEG with high sensitivity and high negative predictive value and may be useful to select patients who should undergo CCEEG.

Emergency management of status epilepticus in a high-fidelity simulation: A prospective study

OBJECTIVES

To quantify the quality of physicians' emergency first response to status epilepticus (SE) and to identify risk factors for nonadherence to treatment guidelines in a standardized simulated scenario.

METHODS

In this prospective trial, 58 physicians (of different background) of the University Hospital Basel, a Swiss academic medical care center, were confronted with a simulated SE. Primary outcomes were time to (1) airway protection, (2) supplementary oxygen, and (3) administration of antiseizure drugs (ASDs).

RESULTS

All physicians recognized ongoing seizures. Airways were checked by 54% and protected by 16% within a median of 3.9 minutes. Supplementary oxygen was administered by 76% with a median of 2.8 minutes. First-line ASDs were administered by 98% (benzodiazepines 97% within a median of 2.9 minutes), and second-line ASDs by 57% within 8.1 minutes. Regarding secondary outcomes, the median time to monitor blood pressure and heart rate was 1.8 (interquartile range [IQR] 1.3-2.6) and 2.0 (IQR 1.4-2.7) minutes, respectively. Neurologic affiliation of physicians was associated with inadequate assessments of vital signs (odds ratio [OR] = 0.2; 95% CI 0.04-0.93) and most frequent administration of second-line ASDs (OR = 5.0; 95% CI 1.01-25.3). Knowing treatment guidelines and subjective certainty regarding SE diagnosis were associated with frequent administration of second-line ASDs (OR = 10.4; 95% CI 1.2-88.1).

CONCLUSIONS

Nonadherence to SE treatment guidelines is frequent. The lack of airway assessment and protection in the simulated clinical scenario of SE may increase mortality and promote treatment refractoriness related to aspiration pneumonia. Guideline-based clinical training is urgently needed to increase the quality of SE management.

REGISTRATION

ISRCTN registry (ID ISRCTN60369617; www.isrctn.com/ISRCTN60369617).

Status Epilepticus, Refractory Status Epilepticus, and Super-refractory Status Epilepticus

PURPOSE OF REVIEW

Status epilepticus, refractory status epilepticus, and super-refractory status epilepticus can be life-threatening conditions. This article presents an overview of the three conditions and discusses their management and outcomes.

RECENT FINDINGS

Status epilepticus was previously defined as lasting for 30 minutes or longer but now is more often defined as lasting 5 minutes or longer. A variety of potential causes exist for status epilepticus, refractory status epilepticus, and super-refractory status epilepticus, but all three ultimately involve changes at the cellular and molecular level. Management of patients with status epilepticus generally requires several studies, with EEG of utmost importance given the pathophysiologic changes that can occur during the course of status epilepticus. Status epilepticus is treated with benzodiazepines as first-line antiepileptic drugs, followed by phenytoin, valproic acid, or levetiracetam. If status epilepticus does not resolve, these are followed by an IV anesthetic and then alternative therapies based on limited data/evidence, such as repetitive transcranial magnetic stimulation, therapeutic hypothermia, immunomodulatory agents, and the ketogenic diet. Scores have been developed to help predict the outcome of status epilepticus. Neurologic injury and outcome seem to worsen as the duration of status epilepticus increases, with outcomes generally worse in super-refractory status epilepticus compared to status epilepticus and sometimes also to refractory status epilepticus.

SUMMARY

Status epilepticus can be a life-threatening condition associated with multiple complications, including death, and can progress to refractory status epilepticus and super-refractory status epilepticus. More studies are needed to delineate the best management of these three entities.

The difficulty of diagnosing NCSE in clinical practice; external validation of the Salzburg criteria

To improve the diagnostic accuracy of electroencephalography (EEG) criteria for nonconvulsive status epilepticus (NCSE), external validation of the recently proposed Salzburg criteria is paramount. We performed an external, retrospective, diagnostic accuracy study of the Salzburg criteria, using EEG recordings from patients with and without a clinical suspicion of having NCSE. Of the 191 EEG recordings, 12 (12%) was classified as an NCSE according to the reference standard. In the validation cohort, sensitivity was 67% and specificity was 89%. The positive predictive value was 47% and the negative predictive value was 95%. Ten patients in the control group (n = 93) were false positive, resulting in a specificity of 89.2%. The interrater agreement between the reference standards and between the scorers of the Salzburg criteria was moderate; disagreement occurred mainly in patients with an epileptic encephalopathy. The Salzburg criteria showed a lower diagnostic accuracy in our external validation study than in the original design, suggesting that they cannot replace the current practice of careful weighing of both clinical and EEG information on an individual basis.

The yield of continuous EEG monitoring in the intensive care unit at a tertiary care hospital in Saudi Arabia: A retrospective study

Background: The practice of continuous EEG monitoring (CEEG) in the intensive care unit (ICU) has spread over the past decade. Building an effective ICU CEEG program demands adequate EEG equipment and human resources. This may not be available in developing healthcare systems. This study sought to shed light on the real-life utility of CEEG at a tertiary healthcare center in the developing healthcare system of Saudi Arabia,. Methods: This is a retrospective review of CEEG findings, along with mortality and duration of hospitalization of patients who had CEEG during a 12-month period at the adult ICU at the King Abdulaziz University Hospital (KAUH) in Jeddah, Saudi Arabia. Results: A total of 202 CEEG records were identified. A total of 52 patients had non-convulsive seizures (NCS); 10 clearly fulfilled criteria for non-convulsive status epilepticus. There were 120 patients that had clinical seizures upon presentation. Among them, 36 (30%) had NCS on EEG. The proportion of patients who were deceased at 60 days was higher in patients with NCS than those who didn't have NCS (42% vs 27%, χ 2 = 4.4, df=2, p=0.03). The proportion with long hospitalization was higher in those who had periodic or rhythmic CEEG patterns (33.3% vs 28.1%, χ 2 = 8.02, df=2, p=0.02) but there was no significant relationship with mortality at 60 days. Conclusion: This study demonstrates a real-world experience from a tertiary care center in Saudi Arabia, a developing healthcare system. Findings are consistent with prior experience that ICU CEEG is effective in detecting potentially harmful subclinical patterns, supporting the need to develop ICU CEEG programs. However, the incurred excesses in morbidity and mortality associated with CEEG patterns were relatively modest. Further studies are needed to delineate how the practice of CEEG may be developed to provide meaningful data to clinicians with regards to patient outcomes.

The yield of continuous EEG monitoring in the intensive care unit at a tertiary care hospital in Saudi Arabia: A retrospective study

Background: The practice of continuous EEG monitoring (CEEG) in the intensive care unit (ICU) has been spreading over the past decade. Building an effective ICU CEEG program with sufficient quality demands adequate EEG equipment and significant human resources. While this is available in large tertiary care centers where the practice of CEEG has developed, it may not be available in developing healthcare systems. This study sought to provide data generated from a CEEG program in the adult ICU at a tertiary healthcare center in Saudi Arabia, shedding light on the real-life utility of CEEG in a developing healthcare system. Methods: This is a retrospective review of CEEG findings, along with mortality and duration of hospitalization of patients who had CEEG during a 12-month period at the adult ICU at the King Abdulaziz University Hospital (KAUH) in Jeddah, Saudi Arabia. Results: A total of 202 CEEG records were identified. A total of 52 patients had non-convulsive seizures (NCS); 10 clearly fulfilled criteria for non-convulsive status epilepticus. There were 120 patients that had clinical seizures upon presentation. Among them, 36 (30%) had NCS on EEG. The proportion of patients who were deceased at 60 days was higher in patients who had NCS (42%) than those who didn't (26%, χ 2  (2, n=200)= 4.4, p=0.03). The duration of hospital stay was longer for those who had periodic or rhythmic CEEG patterns (χ 2 (2, n=200)= 7.6, p=0.02) but there was no significant relationship with mortality at 60 days. Conclusion: This study demonstrates a real-world experience from a tertiary care center in Saudi Arabia, a developing healthcare system. Findings are consistent with prior experience with ICU CEEG, demonstrating that finding ictal, rhythmic or periodic patterns is associated with morbidity and mortality. Further studies are needed to demonstrate how the practice of CEEG may alter patient outcomes.

The yield of continuous EEG monitoring in the intensive care unit at a tertiary care hospital in Saudi Arabia: A retrospective study

Background: The practice of continuous EEG monitoring (CEEG) in the intensive care unit (ICU) has spread over the past decade. Building an effective ICU CEEG program demands adequate EEG equipment and human resources. This may not be available in developing healthcare systems. This study sought to shed light on the real-life utility of CEEG at a tertiary healthcare center in the developing healthcare system of Saudi Arabia. Methods: This is a retrospective review of CEEG findings, along with mortality and duration of hospitalization of patients who had CEEG during a 12-month period at the adult ICU at the King Abdulaziz University Hospital (KAUH) in Jeddah, Saudi Arabia. Results: A total of 202 CEEG records were identified. A total of 52 records showed non-convulsive seizures (NCS); 10 clearly fulfilled criteria for non-convulsive status epilepticus. There were 120 patients that had clinical seizures upon presentation. Among them, 36 (30%) had NCS on EEG. The proportion of patients who were deceased at 60 days was higher in patients with NCS than those who didn't have NCS (42% vs 27%, χ 2 = 4.4, df=2, p=0.03). There was no statistically significant association between having rhythmic or periodic patterns without NCS and mortality at 60 days or length of hospital stay. Conclusion: This retrospective study demonstrates a real-world experience from a tertiary care center in Saudi Arabia, a developing healthcare system. ICU CEEG was found to be effective in detecting potentially harmful subclinical patterns, supporting the need to develop ICU CEEG programs. However, the incurred excesses in morbidity and mortality associated with CEEG patterns were relatively modest. Further studies are needed to delineate how the practice of CEEG may be developed in similar healthcare systems to provide meaningful data to clinicians with regards to patient outcomes.

Untangling operational failures of the Status Epilepticus Severity Score (STESS)

OBJECTIVE

To uncover clinical characteristics leading to false outcome prediction of the Status Epilepticus Severity Score (STESS), a validated and broadly used clinical scoring system for outcome prediction in status epilepticus (SE).

METHODS

From 2005 to 2016, adult patients with SE treated at the University Hospital Basel, Switzerland, were included. To assess independent associations of variables differing between patients with false and correct prediction of death (STESS ≥ 3), multivariable logistic regression models were computed using automated selection.

RESULTS

Among 467 patients, 12% died. The median STESS was 3 (interquartile range 2-4). Regarding prediction of death, the STESS was false-positive in 51% and false-negative in 1%. Patients surviving despite having a STESS ≥3 had less fatal etiologies, less nonconvulsive SE with coma, and lower Charlson Comorbidity Index, Simplified Acute Physiology Score II, and Acute Physiology and Chronic Health Evaluation II scores. In multivariable analyses, odds for survival were high with SE types other than nonconvulsive status with coma and low with an increasing Charlson Comorbidity Index in patients with a STESS ≥ 3 (odds ratio [OR]_{for survival} 4.23, 95% confidence interval [CI] 2.33-9.60; and OR_{for survival} 0.86, 95% CI 0.75-0.98). In patients with SE types other than nonconvulsive with coma, the STESS was mainly increased because they were frequently older than 65 years and had no seizure history.

CONCLUSIONS

The STESS frequently and inadequately predicts death especially in patients with SE other than nonconvulsive with coma and few comorbidities. Clinicians are urged to interpret a STESS ≥3 with caution in such patients.

Acute Non-Convulsive Status Epilepticus after Experimental Traumatic Brain Injury in Rats

Severe traumatic brain injury (TBI) induces seizures or status epilepticus (SE) in 20-30% of patients during the acute phase. We hypothesized that severe TBI induced with lateral fluid-percussion injury (FPI) triggers post-impact SE. Adult Sprague-Dawley male rats were anesthetized with isoflurane and randomized into the sham-operated experimental control or lateral FPI-induced severe TBI groups. Electrodes were implanted right after impact or sham-operation, then video-electroencephalogram (EEG) monitoring was started. In addition, video-EEG was recorded from naïve rats. During the first 72 h post-TBI, injured rats had seizures that were intermingled with other epileptiform EEG patterns typical to non-convulsive SE, including occipital intermittent rhythmic delta activity, lateralized or generalized periodic discharges, spike-and-wave complexes, poly-spikes, poly-spike-and-wave complexes, generalized continuous spiking, burst suppression, or suppression. Almost all (98%) of the electrographic seizures were recorded during 0-72 h post-TBI (23.2 ± 17.4 seizures/rat). Mean latency from the impact to the first electrographic seizure was 18.4 ± 15.1 h. Mean seizure duration was 86 ± 57 sec. Analysis of high-resolution videos indicated that only 41% of electrographic seizures associated with behavioral abnormalities, which were typically subtle (Racine scale 1-2). Fifty-nine percent of electrographic seizures did not show any behavioral manifestations. In most of the rats, epileptiform EEG patterns began to decay spontaneously on Days 5-6 after TBI. Interestingly, also a few sham-operated and naïve rats had post-operation seizures, which were not associated with EEG background patterns typical to non-convulsive SE seen in TBI rats. To summarize, our data show that lateral FPI-induced TBI results in non-convulsive SE with subtle behavioral manifestations; this explains why it has remained undiagnosed until now. The lateral FPI model provides a novel platform for assessing the mechanisms of acute symptomatic non-convulsive SE and for testing treatments to prevent post-injury SE in a clinically relevant context.

Fat Embolism and Nonconvulsive Status Epilepticus

Fat embolism syndrome (FES) typically occurs following orthopedic trauma and may present with altered mental status and even coma. Nonconvulsive status epilepticus is an electroclinical state associated with an altered level of consciousness but lacking convulsive motor activity and has been reported in fat embolism. The diagnosis is clinical and is treated with supportive care, antiepileptic therapy, and sedation. A 56-year-old male presented with altered mental status following internal fixation for an acute right femur fracture due to a motor vehicle accident 24 hours earlier. Continued neuromonitoring revealed nonconvulsive status epilepticus. Magnetic resonance imaging of the brain showed multiple bilateral acute cerebral infarcts with a specific pattern favoring the diagnosis of fat embolism syndrome. He was found to have a significant right to left intracardiac shunt on a transesophageal echocardiogram. He improved substantially over time with supportive therapy, was successfully extubated on day 6, and discharged to inpatient rehabilitation on postoperative day 15. Fat embolisms can result in a wide range of neurologic manifestations. Nonrefractory nonconvulsive status epilepticus that responds to antiepileptic drugs, sedation, and supportive therapy can have a favorable outcome. A high index of suspicion and early recognition reduces the chances of unnecessary interventions and may improve survival.

Reevaluation of the Critically Ill Patients With Nonconvulsive Status Epilepticus by Using Salzburg Consensus Criteria

OBJECTIVE

We aimed to assess the usefulness of the Salzburg Consensus Criteria (SCC) for determining the prognosis of critically ill patients with nonconvulsive status epilepticus (NCSE).

METHODS

We retrospectively reviewed consecutive patients with unconsciousness followed up in the intensive care unit (ICU). Three clinical neurophysiologists, one of them blinded to clinical and laboratory data, reevaluated all EEG data independently and determined NCSE according to SCC. The incidence of NCSE and ictal EEG patterns and their relationship to clinical, laboratory, neuroradiological, and prognostic findings were assessed.

RESULTS

A total of 107 consecutive patients with mean age 68.2 ± 15.3 years (57 females) were enrolled in the study. Primary neuronal injury was detected in 59 patients (55.7%). Thirty-three patients (30.8%) were diagnosed as NCSE. While authors decided to treat 33 patients (30.8%), 32 patients (29.9%) had been treated in real-life evaluation. Clinical and EEG improvement were detected in 12 patients (11.3%) in real-life treatment group showing correlation with lack of intubation and ICU stay related to postsurgical event. Rate of mortality (45.8%) was high showing association with systemic-metabolic etiology, severity of coma and presence of "plus" modifiers in the EEG.

CONCLUSION AND SIGNIFICANCE

Our findings suggest that SCC is highly compatible with clinical practice in the decision for treatment of patients with NCSE. The presence of "plus" modifiers in the EEG was found to be associated with mortality in these patients and was a significant marker for the high mortality rate.

Multimodal Predictions of Super-Refractory Status Epilepticus and Outcome in Status Epilepticus Due to Acute Encephalitis

Objective: Status epilepticus (SE) is one of the most critical symptoms of encephalitis. Studies on early predictions of progression to super-refractory status epilepticus (SRSE) and poor outcome in SE due to acute encephalitis are scarce. We aimed to investigate the values of neuroimaging and continuous electroencephalogram (EEG) in the multimodal prediction. Methods: Consecutive patients with convulsive SE due to acute encephalitis were included in this study. Demographics, clinical features, neuro-imaging characteristics, medical interventions, and anti-epileptic treatment responses were collected. All the patients had EEG monitoring for at least 24 h. We determined the early predictors of SRSE and prognostic factors of 3-month outcome using multivariate logistic regression analyses. Results: From March 2008 to February 2018, 570 patients with acute encephalitis were admitted to neurological intensive care unit (N-ICU) of Xijing hospital. Among them, a total of 94 patients with SE were included in this study. The percentage of non-SRSE and SRSE were 76.6 and 23.4%. Cortical or hippocampal abnormality on neuroimaging (p = 0.002, OR 20.55, 95% CI 3.16-133.46) and END-IT score (p < 0.001, OR 4.07, 95% CI 1.91-8.67) were independent predictors of the progression to SRSE. At 3 months after N-ICU discharge, 56 (59.6%) patients attained good outcomes, and 38 (40.4%) patients had poor outcomes. The recurrence of clinical or EEG seizures within 2 h after the infusion rate of a single anesthetic drug >50% proposed maximal dose (p = 0.044, OR 4.52, 95% CI 1.04-19.68), tracheal intubation (p = 0.011, OR 4.99, 95% CI 1.37-11.69) and emergency resuscitation (p = 0.040, OR 9.80, 95% 1.11-86.47) predicted poor functional outcome. Interpretation: Initial neuro-imaging findings assist early identification of the progression to SRSE. Continuous EEG monitoring contributes to outcome prediction in SE due to acute encephalitis.

Tonic Upward Eyeball Deviation Mimicking Non-Convulsive Occipital Lobe Status Epilepticus That Was Induced by Hydrocephalus

Several seizure-like symptoms are difficult to differentiate from epileptic convulsion, and then if they were misdiagnosed, they could be led to grave prognosis. A 41-year-old man was referred to the emergency room due to unconsciousness. Brain computed tomography (CT) revealed acute subdural hemorrhage along the left frontal lobe, and intraparenchymal hemorrhage in the left temporo-occipital lobe. After emergent decompressive craniectomy, he recovered an alert mental state but became progressively drowsy. Four days later, virtually continuous tonic upward eyeball deviation was observed. He had been taking antiepileptic drugs following an occipital lobectomy 20 years prior due to intractable epilepsy, and we assumed these upward eyeball deviations were symptoms of non-convulsive occipital lobe status epilepticus. Hence, doses and classes of antiepileptic drugs were modified, but clinical manifestations did not improve. Follow-up brain CT revealed newly developed hydrocephalus and compression of the mesencephalon. His symptoms fully resolved after a ventriculo-peritoneal shunt operation. In this case report, we describe the case of a patient exhibiting tonic upward eyeball deviation induced by hydrocephalus that was not associated with a seizure.

Novel TBC1D24 Mutations in a Case of Nonconvulsive Status Epilepticus

Objective: Nonconvulsive status epilepticus (NCSE) is an uncommon clinical manifestation in patients with TBC1D24 mutations. In addition, NCSE has not been reported as a syndrome together with cerebellar ataxia and ophthalmoplegia.

Methods: We herein report the clinical and genetic features of a four-year-old patient with NCSE, cerebellar ataxia, and ophthalmoplegia caused by hitherto unidentified TBC1D24 mutations. We performed 24-h video electroencephalogram (EEG), magnetic resonance imaging, and gene sequencing on the patient and her parents to determine the diagnosis.

Results: We identified a novel c.1416_1437del (p.Ser473Argfs^*43) mutation, as well as the previously identified c.1499C>T (p.Ala500Val) mutation in TBC1D24, by using targeted next-generation sequencing. The novel mutation (inherited from the mother) is the first reported deletion mutation longer than 20 bp in TBC1D24. The p.Ala500Val mutation inherited from father has been reported in a German patient with infantile myoclonic, for whom results from the EEG and neuroimaging were normal. These two mutations resulted in the severe phenotypes observed in our patient

Conclusions: The identification of the novel TBC1D24 mutation and consequent complicated clinical manifestations suggest that patients with NCSE and ataxia demand more attention. We further recommend that genetic test should be administered to these patients to avoid genetic inheritance of this mutation.

Automated Long-Term EEG Review: Fast and Precise Analysis in Critical Care Patients

Background: Ongoing or recurrent seizure activity without prominent motor features is a common burden in neurological critical care patients and people with epilepsy during ICU stays. Continuous EEG (CEEG) is the gold standard for detecting ongoing ictal EEG patterns and monitoring functional brain activity. However CEEG review is very demanding and time consuming. The purpose of the present multirater, EEG expert reviewer study, is to test and assess the clinical feasibility of an automatic EEG pattern detection method (Neurotrend).

Methods: Four board certified EEG reviewers used Neurotrend to annotate 76 CEEG datasets à 6 h (in total 456 h of EEG) for rhythmic and periodic EEG patterns (RPP), unequivocal ictal EEG patterns and burst suppression. All reviewers had a predefined time limit of 5 min (± 2 min) per CEEG dataset and were compared to a predefined gold standard (conventional EEG review with unlimited time). Subanalysis of specific features of RPP was conducted as well. We used Gwet's AC₁ and AC₂ coefficients to calculate interrater agreement (IRA) and multirater agreement (MRA). Also, we determined individual performance measures for unequivocal ictal EEG patterns and burst suppression. Bonferroni-Holmes correction for multiple testing was applied to all statistical tests.

Results: Mean review time was 3.3 min (± 1.9 min) per CEEG dataset. We found substantial IRA for unequivocal ictal EEG patterns (0.61–0.79; mean sensitivity 86.8%; mean specificity 82.2%, p < 0.001) and burst suppression (0.68–0.71; mean sensitivity 96.7%; mean specificity 76.9% p < 0.001). Two reviewers showed substantial IRA for RPP (0.68–0.72), whereas the other two showed moderate agreement (0.45–0.54), compared to the gold standard (p < 0.001). MRA showed almost perfect agreement for burst suppression (0.86) and moderate agreement for RPP (0.54) and unequivocal ictal EEG patterns (0.57).

Conclusions: We demonstrated the clinical feasibility of an automatic critical care EEG pattern detection method on two levels: (1) reasonable high agreement compared to the gold standard, (2) reasonable short review times compared to previously reported EEG review times with conventional EEG analysis.

The relevance of timing in nonconvulsive status epilepticus: A series of 38 cases

BACKGROUND

Timing in the management of nonconvulsive status epilepticus (NCSE) seems to be one of the most important modifiable prognostic factors. We aimed to determine the precise relationship between timing in NCSE management and its outcome.

METHODS

We performed a cross-sectional study in which clinical data were prospectively obtained from all consecutive adults with NCSE admitted to our hospital from 2014 to 2016. Univariate and multivariable regression analyses were performed to identify clinical and timing variables associated with NCSE prognosis.

RESULTS

Among 38 NCSE cases, 59.9% were women, and 39.5% had prior epilepsy history. The median time to treatment (TTT) initiation and the median time to assessment by a neurologist (TTN) were 5h, and the median time to first electroencephalography assessment was 18.5h; in the cases with out-of-hospital onset (n=24), the median time to hospital (TTH) arrival was 2.8h. The median time to NCSE control (TTC) was 16.5h, and it positively correlated with both the TTH (Spearman's rho: 0.439) and the TTT (Spearman's rho: 0.683). In the multivariable regression analyses, the TTC was extended 1.7h for each hour of hospital arrival delay (p=0.01) and 2.7h for each hour of treatment delay (p<0.001). Recognition delay was more common in the episodes with in-hospital onset, which also had longer TTN and TTC, and increased morbidity.

CONCLUSIONS

There were pervasive delays in all phases of NCSE management. Delays in hospital arrival or treatment initiation may result in prolonged TTC. Recognition of in-hospital episodes may be more delayed, which may lead to poorer prognosis in these cases.

Non-convulsive status epilepticus: mimics and chameleons

Non-convulsive status epilepticus (NCSE) is an enigmatic condition with protean manifestations. It often goes unrecognised, leading to delays in its diagnosis and treatment. The principal reason for such delay is the failure to consider and request an electroencephalogram (EEG), although occasional presentations have no scalp or surface electroencephalographic correlate. In certain settings with limited EEG availability, particularly out-of-hours, clinicians should consider treating without an EEG. Patients need a careful risk–benefit analysis to assess the risks of neuronal damage and harm versus the risks of adverse effects from various intensities of therapeutic intervention. Specialists in EEG, intensive care or epilepsy are invaluable in the management of patients with possible NCSE.

Nonconvulsive status epilepticus after convulsive status epilepticus: Clinical features, outcomes, and prognostic factors

OBJECTIVES

To investigate clinical characteristics and outcomes of nonconvulsive status epilepticus (NCSE) after convulsive status epilepticus (CSE) and determine risk factors for unfavorable outcomes.

METHODS

We reviewed consecutive patients with NCSE after CSE over eight years in the neurological intensive care unit. Clinical presentations and the Salzburg EEG criteria for NCSE were used to identify patients with NCSE after CSE. Demographics, clinical features, and anti-epileptic treatment responses were collected and analyzed. Modified Rankin Scale (mRS) was used to evaluate three-month outcomes. A multivariate logistic regression model was used to determine independent prognostic factors.

RESULTS

Among 145 consecutive patients with convulsive SE, 48 (33.1%) patents eventually evolved into NCSE. Two patients with cerebral anoxia were exclude. At three-month follow-up, 23 patients (50.0%) had mRS ≥ 3, and 16 (34.8%) died. Thirty-two patients (69.6%) were given continuous intravenous anesthetic drugs (CIVADs). Fourteen patients (30.4%) had CIVAD at the rate >50% proposed maximal dose (PMD). There was a single predictor factor found significant after multivariate logistic regression analysis: the recurrence of EEG seizures within two hours of initiation of CIVAD at a dose of greater than half the proposed maximal dose (OR, 9.63; 95%CI, 1.08-86.18; p = 0.043). The use of CIVAD, even with a high dose (>50% PMD), was not independently associated with unfavorable outcomes.

CONCLUSIONS

The recurrence of EEG seizures within two hours of initiation of CIVAD at a dose of greater than half the proposed maximal dose predicts unfavorable outcomes in NCSE after CSE. The refractoriness of the seizures might be a significantly greater risk for poor outcome in NCSE after CSE than treatment with CIVADs.

Effect of thymectomy on refractory autoimmune status epilepticus

Refractory status epilepticus (RSE) is an increasingly recognized manifestation of autoimmune encephalitis, which can occur either as a paraneoplastic or non-paraneoplastic disorder. The effect of tumor removal in paraneoplastic status epilepticus has never been explored systematically, although early tumor treatment is usually recommended. In this study, we report clinical, pathological and EEG findings of a patient who developed RSE as one of multiple paraneoplastic manifestations of thymoma and the effect of thymectomy on seizure outcome. To our knowledge, this is the first report of successful treatment of RSE with tumor removal in paraneoplastic encephalitis.

Hidden in plain sight: Non-convulsive status epilepticus-Recognition and management

Non-convulsive status epilepticus (NCSE) is an electroclinical state associated with an altered level of consciousness but lacking convulsive motor activity. It can present in a multitude of ways, but classification based on the clinical presentation and electroencephalographic appearances assists in determining prognosis and planning treatment. The aggressiveness of treatment should be based on the likely prognosis and the underlying cause of the NCSE.

Chimeric antigen receptor T-cell therapy - assessment and management of toxicities

Immunotherapy using T cells genetically engineered to express a chimeric antigen receptor (CAR) is rapidly emerging as a promising new treatment for haematological and non-haematological malignancies. CAR-T-cell therapy can induce rapid and durable clinical responses, but is associated with unique acute toxicities, which can be severe or even fatal. Cytokine-release syndrome (CRS), the most commonly observed toxicity, can range in severity from low-grade constitutional symptoms to a high-grade syndrome associated with life-threatening multiorgan dysfunction; rarely, severe CRS can evolve into fulminant haemophagocytic lymphohistiocytosis (HLH). Neurotoxicity, termed CAR-T-cell-related encephalopathy syndrome (CRES), is the second most-common adverse event, and can occur concurrently with or after CRS. Intensive monitoring and prompt management of toxicities is essential to minimize the morbidity and mortality associated with this potentially curative therapeutic approach; however, algorithms for accurate and consistent grading and management of the toxicities are lacking. To address this unmet need, we formed a CAR-T-cell-therapy-associated TOXicity (CARTOX) Working Group, comprising investigators from multiple institutions and medical disciplines who have experience in treating patients with various CAR-T-cell therapy products. Herein, we describe the multidisciplinary approach adopted at our institutions, and provide recommendations for monitoring, grading, and managing the acute toxicities that can occur in patients treated with CAR-T-cell therapy.

An update on the recognition and treatment of non-convulsive status epilepticus in the intensive care unit

INTRODUCTION

Non-convulsive status epilepticus (NCSE) is a complex and diverse condition which is often an under-recognised entity in the intensive care unit. When NCSE is identified the optimal treatment strategy is not always clear. Areas covered: This review is based on a literature review of the key literature in the field over the last 5-10 years. The articles were selected based on their importance to the field by the authors. Expert commentary: This review discusses the complex situations when a neurological consultation may occur in a critical care setting and provides an update on the latest evidence regarding the recognition of NCSE and the decision making around determining the aggressiveness of treatment. It also considers the ictal-interictal continuum of conditions which may be met with, particularly in the era of continuous EEG, and provides an approach for dealing with these. Suggestions for how the field will develop are discussed.

Early post-traumatic seizures are associated with valproic acid plasma concentrations and UGT1A6/CYP2C9 genetic polymorphisms in patients with severe traumatic brain injury

BACKGROUND

Seizure is a common complication for severe traumatic brain injury (TBI). Valproic acid (VPA) is a first-line antiepileptic drug, though its metabolism is affected by genetic polymorphisms and varies between individuals. The aim of this study was to investigate such association and to explore its influence on the occurrence of early post-traumatic seizure.

METHODS

A prospective case control study was conducted from 2012 to 2016 recruiting adult patients with severe TBI. Electroencephalograph (EEG) monitoring was performed approximately 4 h for each patient from day 1 to day 7 after injury. If seizures were detected, EEG monitoring was extended until 12 h after seizures being controlled. Genetic polymorphisms in UGT1A6, UGT2B7, CYP2C9, and CYP2C19 were analyzed in association with daily VPA plasma concentrations, adjusted dosages, and occurrence of seizures.

RESULTS

Among the 395 recruited patients, eighty-three (21%) had early post-traumatic seizure, of which 30 (36.14%) were non-convulsive. Most seizures were first detected on day 1 (34.94%) and day 2 (46.99%) after injury. Patients with seizure had longer ICU length of stay and relatively lower VPA plasma concentrations. Patients with UGT1A6_19T > G/541A > G/552A > C double heterozygosities or CYP2C9 extensive metabolizers (EMs) initially had lower adjusted VPA plasma concentrations (power >0.99) and accordingly require higher VPA dosages during later time of treatment (power >0.99). The odds ratio indicated a higher risk of early post-traumatic seizure occurrence in male patients (OR 1.96, 95% CI 1.01-3.81, p = 0.043), age over 65 (OR 2.13, 95% CI 1.01-4.48), and with UGT1A6_19T > G/541A > G/552A > C double heterozygosities (OR 2.38, 95% CI 1.11-5.10, p = 0.02), though the power of the difference was between 0.54 to 0.61.

DISCUSSION

Due to limited facility, the actual frequency of non-convulsive seizures is suspected to be higher than identified. There has been discrepancy regarding to genetic polymorphisms and VPA metab olism between this study and some previous reports. This could be related to confounders such as sample size, race, and patient age. Another limitation is that the case numbers of certain genotypes are limited in this study.

CONCLUSIONS

Continuous EEG monitoring is necessary to detect both convulsive and non-convulsive early post-traumatic seizures in severe TBI patients. UGT1A6/CYP2C9 polymorphisms have influence on VPA metabolism. UGT1A6_19T > G/541A > G/552A > C double heterozygositie is associated with occurrence of early post-traumatic seizures in addition to patients' age and gender. Further investigations with larger sample size are required to confirm the difference.

TRIAL REGISTRATION

Retrospectively registered with Chinese Clinical Trail Registry on 1st Jan 2016 ( ChiCTR-OPC-16007687 ).

Pitfalls in the Diagnosis and Management of Invasive Pneumococcal Meningoencephalitis - What We Can Learn From a Case

Invasive pneumococcal meningitis is a life-threatening infectious disease affecting the central nervous system. It continues to be the most common type of community-acquired acute bacterial meningitides. Despite advances in neuro-critical care, the case fatality rate remains high. Rapid diagnosis and initiation of antibiotic therapy precludes mortality and long-term neurological sequelae in survivors. However, not all cases are easily recognised, and unanticipated complications may impede optimal course and outcome. Here, we describe a case of invasive pneumococcal meningoencephalitis in a 65-year-old man with an unusual initial presentation and pitfalls in the course of the disease. We highlight the importance of early diagnosis and treatment as well as recognition and management of complications.

Transition from intravenous to enteral ketamine for treatment of nonconvulsive status epilepticus

Background

Nonconvulsive status epilepticus (NCSE) is a diagnosis that is often challenging and one that may progress to refractory NCSE. Ketamine is a noncompetitive N-methyl-d-aspartate antagonist that increasingly has been used to treat refractory status epilepticus. Current Neurocritical Care Society guidelines recommend intravenous (IV) ketamine infusion as an alternative treatment for refractory status epilepticus in adults. On the other hand, enteral ketamine use in NCSE has been reported in only 6 cases (1 adult and 5 pediatric) in the literature to date.

Case presentation

A 33-year-old woman with a history of poorly controlled epilepsy presented with generalized tonic-clonic seizures, followed by recurrent focal seizures that evolved into NCSE. This immediately recurred within 24 h of a prior episode of NCSE that was treated with IV ketamine. Considering her previous response, she was started again on an IV ketamine infusion, which successfully terminated NCSE. This time, enteral ketamine was gradually introduced while weaning off the IV formulation. Treatment with enteral ketamine was continued for 6 months and then tapered off. There was no recurrence of NCSE or seizures and no adverse events noted during the course of treatment.

Conclusion

This case supports the use of enteral ketamine as a potential adjunct to IV ketamine in the treatment of NCSE, especially in cases without coma. Introduction of enteral ketamine may reduce seizure recurrence, duration of stay in ICU, and morbidity associated with intubation.

Emergency response to out-of-hospital status epilepticus

Objective:

To determine the implications of first responses of emergency medical services (EMS) to out-of-hospital status epilepticus (SE) on outcome.

Methods:

From 2005 to 2014, prehospital and in-hospital data were assessed in consecutive adults admitted to an academic medical center with out-of-hospital SE. Logistic regression was performed to identify variables with a robust association between missed epileptic events by the EMS and no recovery to functional baseline in survivors.

Results:

Among 213 SE patients, 150 were admitted via EMS. While nonconvulsive SE (NCSE) was missed by the EMS in 63.7%, convulsive SE (CSE) was not missed except in 4 patients with transformation into subtle SE. Missed NCSE was more likely with older age (odds ratio [OR]per year 1.06, 95% confidence interval [CI] 1.02–1.10, p = 0.003) and no seizure history (OR 6.64, 95% CI 2.43–18.1, p < 0.001). The area under the receiver operating characteristic curve for prediction of missed NCSE by these variables was 0.839. Independent predictors for not receiving benzodiazepines were increasing age (ORper year 1.05, 95% CI 1.01–1.08, p = 0.008) and higher Glasgow Coma Scale score (ORper increasing unit 1.21, 95% CI 1.09–1.36, p = 0.001). Missed NCSE was independently associated with increased odds for no return to functional baseline in survivors (OR 3.83, 95% CI 1.22–11.98, p = 0.021).

Conclusions:

Among patients admitted with out-of-hospital SE, CSE is mostly recognized while NCSE is frequently missed especially in patients with increasing age and no seizure history. This calls for heightened awareness for out-of-hospital NCSE in such patients, as missed NCSE is associated with lack of treatment and less recovery to functional baseline in survivors independent of established outcome predictors.

Electroencephalographic Periodic Discharges and Frequency-Dependent Brain Tissue Hypoxia in Acute Brain Injury

Importance

Periodic discharges (PDs) that do not meet seizure criteria, also termed the ictal interictal continuum, are pervasive on electroencephalographic (EEG) recordings after acute brain injury. However, their association with brain homeostasis and the need for clinical intervention remain unknown.

Objective

To determine whether distinct PD patterns can be identified that, similar to electrographic seizures, cause brain tissue hypoxia, a measure of ongoing brain injury.

Design, Setting, and Participants

This prospective cohort study included 90 comatose patients with high-grade spontaneous subarachnoid hemorrhage who underwent continuous surface (scalp) EEG (sEEG) recording and multimodality monitoring, including invasive measurements of intracortical (depth) EEG (dEEG), partial pressure of oxygen in interstitial brain tissue (Pbto2), and regional cerebral blood flow (CBF). Patient data were collected from June 1, 2006, to September 1, 2014, at a single tertiary care center. The retrospective analysis was performed from September 1, 2014, to May 1, 2016, with a hypothesis that the effect on brain tissue oxygenation was primarily dependent on the discharge frequency.

Main Outcomes and Measures

Electroencephalographic recordings were visually classified based on PD frequency and spatial distribution of discharges. Correlations between mean multimodality monitoring data and change-point analyses were performed to characterize electrophysiological changes by applying bootstrapping.

Results

Of the 90 patients included in the study (26 men and 64 women; mean [SD] age, 55 [15] years), 32 (36%) had PDs on sEEG and dEEG recordings and 21 (23%) on dEEG recordings only. Frequencies of PDs ranged from 0.5 to 2.5 Hz. Median Pbto2 was 23 mm Hg without PDs compared with 16 mm Hg at 2.0 Hz and 14 mm Hg at 2.5 Hz (differences were significant for 0 vs 2.5 Hz based on bootstrapping). Change-point analysis confirmed a temporal association of high-frequency PD onset (≥2.0 Hz) and Pbto2 reduction (median normalized Pbto2 decreased by 25% 5-10 minutes after onset). Increased regional CBF of 21.0 mL/100 g/min for 0 Hz, 25.9 mL/100 g/min for 1.0 Hz, 27.5 mL/100 g/min for 1.5 Hz, and 34.7 mL/100 g/min for 2.0 Hz and increased global cerebral perfusion pressure of 91 mm Hg for 0 Hz, 100.5 mm Hg for 0.5 Hz, 95.5 mm Hg for 1.0 Hz, 97.0 mm Hg for 2.0 Hz, 98.0 mm Hg for 2.5 Hz, 95.0 mm Hg for 2.5 Hz, and 67.8 mm Hg for 3.0 Hz were seen for higher PD frequencies.

Conclusions and Relevance

These data give some support to consider redefining the continuum between seizures and PDs, suggesting that additional damage after acute brain injury may be reflected by frequency changes in electrocerebral recordings. Similar to seizures, cerebral blood flow increases in patients with PDs to compensate for the increased metabolic demand but higher-frequency PDs (>2 per second) may be inadequately compensated without an additional rise in CBF and associated with brain tissue hypoxia, or higher-frequency PDs may reflect inadequacies in brain compensatory mechanisms.

Semiology of subtle motor phenomena in critically ill patients

PURPOSE

to investigate the semiology of subtle motor phenomena in critically ill patients, with- versus without nonconvulsive status epilepticus (NCSE).

METHODS

60 consecutive comatose patients, in whom subtle motor phenomena were observed in the intensive care unit (ICU), were analysed prospectively. The semiology of the subtle phenomena was described from video-recordings, blinded to all other data. For each patient, the type, location and occurrence-pattern/duration were described. EEGs recorded in the ICU were classified using the Salzburg criteria for NCSE.

RESULTS

only 23% (14/60) of the patients had NCSE confirmed by EEG. None of the semiological features could distinguish between patients with NCSE and those without. In both groups, the following phenomena were most common: discrete myoclonic muscle twitching and discrete tonic muscle activation. Besides these, automatisms and eye deviation were observed in both groups.

CONCLUSION

subtle motor phenomena in critically ill patients can raise the suspicion of NCSE. Nevertheless, EEG is needed to confirm the diagnosis, since none of the semiological features are specific.