Responsive neurostimulation as a therapy for epilepsy following new-onset refractory status epilepticus: Case series and review of the literature

OBJECTIVE

To report clinical outcomes of patients who presented with new-onset refractory status epilepticus (NORSE), developed drug-resistant epilepsy (DRE), and were treated with responsive neurostimulation (RNS).

METHODS

We performed a retrospective review of patients implanted with RNS at our institution and identified three who originally presented with NORSE. Through chart review, we retrieved objective and subjective information related to their presentation, workup, and outcomes including patient-reported seizure frequency. We reviewed electrocorticography (ECoG) data to estimate seizure burden at 3, 6, 12, and 24 months following RNS implantation. We performed a review of literature concerning neurostimulation in NORSE.

RESULTS

Use of RNS to treat DRE following NORSE was associated with reduced seizure burden and informed care by differentiating epileptic from non-epileptic events.

CONCLUSIONS

Our single-center experience of three cases suggests that RNS is a safe and potentially effective treatment for DRE following NORSE.

SIGNIFICANCE

This article reports outcomes of the largest case series of NORSE patients treated with RNS. Since patients with NORSE are at high risk of adverse neuropsychiatric and cognitive sequelae beyond seizures, a unique strength of RNS over other surgical options is the ability to distinguish ictal or peri-ictal from non-epileptic events.

Responsive deep brain stimulation guided by ventral striatal electrophysiology of obsession durably ameliorates compulsion

Treatment-resistant obsessive-compulsive disorder (OCD) occurs in approximately one-third of OCD patients. Obsessions may fluctuate over time but often occur or worsen in the presence of internal (emotional state and thoughts) and external (visual and tactile) triggering stimuli. Obsessive thoughts and related compulsive urges fluctuate (are episodic) and so may respond well to a time-locked brain stimulation strategy sensitive and responsive to these symptom fluctuations. Early evidence suggests that neural activity can be captured from ventral striatal regions implicated in OCD to guide such a closed-loop approach. Here, we report on a first-in-human application of responsive deep brain stimulation (rDBS) of the ventral striatum for a treatment-refractory OCD individual who also had comorbid epilepsy. Self-reported obsessive symptoms and provoked OCD-related distress correlated with ventral striatal electrophysiology. rDBS detected the time-domain area-based feature from invasive electroencephalography low-frequency oscillatory power fluctuations that triggered bursts of stimulation to ameliorate OCD symptoms in a closed-loop fashion. rDBS provided rapid, robust, and durable improvement in obsessions and compulsions. These results provide proof of concept for a personalized, physiologically guided DBS strategy for OCD.

Multigene Panel Testing in a Large Cohort of Adults With Epilepsy: Diagnostic Yield and Clinically Actionable Genetic Findings

Background and Objectives

Although genetic testing among children with epilepsy has demonstrated clinical utility and become a part of routine testing, studies in adults are limited. This study reports the diagnostic yield of genetic testing in adults with epilepsy.

Methods

Unrelated individuals aged 18 years and older who underwent diagnostic genetic testing for epilepsy using a comprehensive, next-generation sequencing-based, targeted gene panel (range 89–189 genes) were included in this cross-sectional study. Clinical information, provided at the discretion of the ordering clinician, was reviewed and analyzed. Diagnostic yield was calculated for all individuals including by age at seizure onset and comorbidities based on clinician-reported information. The proportion of individuals with clinically actionable genetic findings, including instances when a specific treatment would be indicated or contraindicated due to a diagnostic finding, was calculated.

Results

Among 2,008 individuals, a diagnostic finding was returned for 218 adults (10.9%), with clinically actionable findings in 55.5% of diagnoses. The highest diagnostic yield was in adults with seizure onset during infancy (29.6%, 0–1 year), followed by in early childhood (13.6%, 2–4 years), late childhood (7.0%, 5–10 years), adolescence (2.4%, 11–17 years), and adulthood (3.7%, ≥18 years). Comorbid intellectual disability (ID) or developmental delay resulted in a high diagnostic yield (16.0%), most notably for females (19.6% in females vs 12.3% in males). Among individuals with pharmacoresistant epilepsy, 13.5% had a diagnostic finding, and of these, 57.4% were clinically actionable genetic findings.

Discussion

These data reinforce the utility of genetic testing for adults with epilepsy, particularly for those with childhood-onset seizures, ID, and pharmacoresistance. This is an important consideration due to longer survival and the complexity of the transition from pediatric to adult care. In addition, more than half of diagnostic findings in this study were considered clinically actionable, suggesting that genetic testing could have a direct impact on clinical management and outcomes.

How to Help Your Patients Enroll in the New-Onset Refractory Status Epilepticus (NORSE) and Febrile Infection-Related Epilepsy Syndrome (FIRES) Family Registry, and Other Rare Epilepsy Registries

New-onset refractory status epilepticus (NORSE) is a rare clinical presentation of refractory status epilepticus (RSE) that occurs in people without active epilepsy or preexisting neurologic disorder. Febrile infection-related epilepsy syndrome (FIRES) is a subcategory of NORSE. New-onset refractory status epilepticus/FIRES are becoming increasingly recognized; however, information pertaining to disease course, clinical outcomes, and survivorship remains limited, and mortality and morbidity are variable, but often high. The objective of the NORSE/FIRES Family Registry is to (1) provide an easily accessible and internationally available multilingual registry into which survivors or NORSE/FIRES surrogates or family members of people affected by NORSE/FIRES or their physicians can enter data in a systematic and rigorous research study from anywhere in the world where internet is available; and (2) to examine past medical history, outcomes, and quality of life for people affected by NORSE/FIRES.

Marijuana use among patients with epilepsy at a tertiary care center

The expansion of medical and recreational marijuana legalization facilitates patient access to cannabis, and many patients with epilepsy pursue marijuana as a treatment for seizures. We administered a nine-item survey on marijuana use to patients seen in an epilepsy clinic over a 9 month period at a tertiary care center in Oregon where recreational use was legalized in 2015. The majority of respondents (n = 39) reported cannabis use for the purpose of treating epilepsy (87.2%, n = 34), and strongly agreed (53.8%, n = 21) or agreed (28.2%, n = 11) that cannabis use improved seizure control. The most commonly selected cannabis strains were high cannabidiol (CBD) (30.8%, n = 12) or multiple types (30.8%, n = 12), with administration methods of smoking (66.7%, n = 26), edibles (48.7%, n = 19), and concentrates (43.6%, n = 17). More participants reported using marijuana with primarily CBD than primarily tetrahydrocannabinol (THC) or equal CBD:THC content, and very few women reported using marijuana with primarily THC compared with men (10% of female versus 47% of male respondents). Only 2 of 39 participants were able to give an exact dosage used in milligrams. Medical and recreational dispensaries were the most common cannabis sources, followed by homegrown and friends/family members. Although pharmaceutical CBD extract is now Food and Drug Administration (FDA)-approved for certain epilepsy types, access remains limited. Further research is needed to understand recreational cannabis use among patients with epilepsy while clinical research for pharmaceutical cannabis products continues.

Psychogenic non-epileptic seizures among patients with functional neurological disorder: A case series from a Tanzanian referral hospital and literature review

Objective

Functional neurological disorders (FNDs) and psychogenic nonepileptic seizures (PNES) are likely as common in Sub-Saharan Africa (SSA) as in the rest of the world, but there is a dearth of literature on the epidemiology and clinical presentation of these disorders in Africa. The purpose of this paper is to describe a case series of FNDs presenting to a referral hospital in SSA. In addition, we review the existing literature on FNDs in Africa.

Methods

A hospital-based retrospective cross-sectional study was conducted to determine the prevalence, epidemiology, and clinical phenotype of FNDs and PNES in a referral hospital in Northern Tanzania over a 6-year period (2007-2013).

Results

Of 2,040 patients presenting with neurological complaints, 44 (2.2%) were diagnosed with FNDs. Half (n = 22) had the clinical presentation of PNES. Age of presentation for FNDs and PNES peaked in the teen years 12-19 (n = 21 48%; and n = 14, 63%, respectively), and the majority were female (n = 30, 68%; and n = 14, 63%, respectively). The majority presented acutely with short-lived and self-limiting symptoms (only 2 recurrent cases). Literature review revealed multiple reports of "mass hysteria" in SSA often meeting the clinical criteria of epidemic FNDs.

Significance

FNDs and PNES occur in Africa with age and gender distribution comparable to that found elsewhere. Although the percentage of FND cases overall was relatively low (2.2%), it is likely to be an underestimate because not all cases were recorded, and cases may be appropriately managed locally before patients are referred to a hospital. PNES was the most common phenotype of FNDs reported, and the African phenotype may be short-lived and self-limiting rather than chronic and recurrent, as reported elsewhere in the world. PNES presentations may also occur in clusters, which may have cultural significance in Africa. FNDs in Africa appear to be underreported, particularly over the last 30 years.

Neurodevelopmental Effects of Antiepileptic Drugs

Increasing evidence suggests that exposure to certain antiepileptic drugs (AEDs) during critical periods of development may induce transient or long-lasting neurodevelopmental deficits across cognitive, motor and behavioral domains. The developing nervous system may endure prolonged chronic exposure to AEDs during pregnancy (in utero) or during childhood, which can lead to neurodevelopmental defects such as congenital neural tube defects, lower IQ, language deficits, autism and ADHD. To date, valproate is the most widely recognized AED to significantly negatively affect neurodevelopment, and demonstrates greater adverse effects than any other AEDs that have been assessed. Although some AEDs appear to have low risk (i.e., lamotrigine, levetiracetam), other AEDs have been implicated in a variety of studies detailed below, and many AEDs have not been adequately assessed. The purpose of this review article is to summarize our current understanding of the neurodevelopmental effects of AEDs.

Health care utilization following diagnosis of psychogenic nonepileptic seizures

OBJECTIVES

The long-term outcome of patients with psychogenic nonepileptic seizures (PNES) is of importance given the disabling symptoms and tendency to affect patients early in their productive years. Health care utilization (HCU) is an important outcome measure reflecting overall health status and costs. There is little information regarding long-term HCU following diagnosis of PNES.

METHODS

We retrospectively reviewed records of Veterans diagnosed with PNES during epilepsy monitoring unit (EMU) evaluation. For the three-year period following diagnosis of PNES, we reviewed emergency department (ED) visits, hospitalizations, outpatient clinic visits, and radiology procedures. We compared the three years following PNES diagnosis with the three years preceding diagnosis. We also compared patients with PNES and patients with epileptic seizures (ES).

RESULTS

Emergency department visits and hospitalizations were more frequent in patients with PNES compared with those in patients with ES (p=0.01). There was no overall improvement in HCU during the three-year interval following diagnosis of PNES. A transient decrease during the year following diagnosis was not sustained over three-year follow-up. Pain complaints rather than seizures were the most common reason for presentation, whereas the opposite was true for patients with ES (p<0.01). There was a sharp decrease in neurology outpatient visits (p<0.001) and a decrease in primary care visits (p<0.05) after PNES was diagnosed. Total outpatient visits were unchanged.

CONCLUSIONS

Overall HCU did not improve during the three years following diagnosis of PNES, compared with three years preceding diagnosis. The results add to studies documenting poor seizure outcomes following diagnosis of PNES and underscore the need for more effective and comprehensive treatments, addressing comorbid symptoms.

INCIDENCE OF GASTRIC ULCER IN ALBINO RATS FED DIETS DEFICIENT IN VITAMIN B (B(1))

73 per cent of a group of albino rats whose diet was deficient in vitamin B have been found to have ulcerations of the gastric mucosa. A control group was found to be free from gastric lesions. Of 74 observed lesions eight were chronic, indurated ulcers resembling chronic peptic ulcer in man. The chronicity of the ulcers seems to be related to the duration rather than the degree of the deficiency. The lesions were generally located along the lesser curvature of the stomach, as is true in man. The size of the lesions in rat and man are comparable if adjustment is made for differences in the sizes of the organs.

Vanishing Hall resistance at high magnetic field in a double-layer two-dimensional electron system

At total Landau level filling factor nu(tot)=1 a double-layer two-dimensional electron system with small interlayer separation supports a collective state possessing spontaneous interlayer phase coherence. This state exhibits the quantized Hall effect when equal electrical currents flow in parallel through the two layers. In contrast, if the currents in the two layers are equal, but oppositely directed, both the longitudinal and Hall resistances of each layer vanish in the low-temperature limit. This finding supports the prediction that the ground state at nu(tot)=1 is an excitonic superfluid.

Bilayer quantum hall systems at nu(T)=1: coulomb drag and the transition from weak to strong interlayer coupling

Measurements revealing anomalously large frictional drag at the transition between the weakly and strongly coupled regimes of a bilayer two-dimensional electron system at total Landau level filling factor nu(T)=1 are reported. This result suggests the existence of fluctuations, either static or dynamic, near the phase boundary separating the quantized Hall state at small layer separations from the compressible state at larger separations. Interestingly, the anomalies in drag seem to persist to larger layer separations than does interlayer phase coherence as detected in tunneling.

Observation of quantized Hall drag in a strongly correlated bilayer electron system

The frictional drag between parallel two-dimensional electron systems has been measured in a regime of strong interlayer correlations. When the bilayer system enters the excitonic quantized Hall state at total Landau level filling factor nu(T) = 1, the longitudinal component of the drag vanishes but a strong Hall component develops. The Hall drag resistance is observed to be accurately quantized at h/e(2).

The use of radiolabeled anti-CD33 antibody to augment marrow irradiation prior to marrow transplantation for acute myelogenous leukemia

Disease recurrence remains a major limitation to the use of marrow transplantation to treat leukemia. Previous transplant studies have demonstrated that higher doses of total-body irradiation result in less disease recurrence, but more toxicity. In this study, the possibility of delivering radiotherapy specifically to marrow using a radiolabeled anti-CD33 antibody (p67) was explored. Biodistribution studies were performed in nine patients using .05-.5 mg/kg p67 trace-labeled with 131I. In most patients initial specific uptake of 131I-p67 in the marrow was seen, but the half-life of the radiolabel in the marrow space was relatively brief, ranging from 9-41 hr, presumably due to modulation of the 131I-p67-CD33 complex with subsequent digestion and release of 131I from the marrow space. In four of nine patients these biodistribution studies demonstrated that with 131I-p67 marrow and spleen would receive more radiation than any normal nonhematopoietic organ, and therefore these four patients were treated with 110-330 mCi 131I conjugated to p67 followed by a standard transplant regimen of cyclophosphamide plus 12 Gy TBI. All four patients tolerated the procedure well and three of the four are alive in remission 195-477 days posttransplant. This study demonstrates the feasibility of using a radiolabeled antimyeloid antibody as part of a marrow transplant preparative regimen and also highlights a major limitation of using conventionally labeled anti-CD33--namely, the short residence time in marrow. Strategies to overcome this limitation include the use of alternative labeling techniques or the selection of cell surface stable antigens as targets.

Pharmacokinetic studies in animals of a new parenteral penem CP-65,207 and its oral prodrug ester

The pharmacokinetics of penem CP-65,207 diastereomeric mixture were studied following parenteral administration in mice, rats, beagle dogs and cynomolgus monkeys. As is characteristic for most penems, the serum elimination T1/2 of CP-65,207 in rodents was only 13 minutes for mice and 18 minutes for rats. A linear relationship was observed between dose and Cmax following subcutaneous injection of drug in mice. The T1/2 in the beagle dog and monkey following intravenous injection was approximately 23 minutes. CP-65,207 demonstrated binding to human serum proteins of only 10%. In vitro studies using purified porcine renal dehydropeptidase-I (RDHP) indicated that the pure S-isomer of CP-65,207 was 7-fold more stable to inactivation than imipenem. Urinary recovery of CP-65,207 in the dog was 42% compared to 1% for imipenem without RDHP inhibitor. Unlike results obtained with imipenem, coadministration of probenecid with CP-65,207 in the dog doubled the elimination T1/2 and AUC of the penem demonstrating its relative stability in vivo in the absence of a RDHP inhibitor. The pivaloyloxymethyl esters of each pure isomer of CP-65,207 showed significantly different degrees of oral absorption in rats.