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

Alpha-2a adrenergic receptor activation in genetic absence epilepsy: An absence status model?

OBJECTIVE

The objective of the study was to propose a candidate animal model of absence status epilepticus induced by specific alpha-2a adrenergic receptor (α2AR) activation. We also aim to investigate the responsiveness of this model to classical anti-status or anti-absence medications.

METHODS

An α2AR agonist, dexmedetomidine (DEX), was injected intracerebroventricularly into adult rats with genetic absence epilepsy, and their electroencephalography (EEG) was recorded. The total duration, number, and mean duration of each spike-and-wave discharges (SWDs) were evaluated. The blocks of absence status events were classified as the initial and second sets of absence statuses. Ethosuximide (ETX) was administered as a pretreatment to another group of rats and later injected with 2.5 μg DEX. In addition, ETX, valproic acid (VPA), diazepam (DIAZ), and atipamezole (ATI) were administered after induced status-like events following DEX administration. Power spectral characteristics and coherence analysis were performed on the EEG to assess the absence status events and sleep.

RESULTS

The 2.5 μg dose of DEX increased the total SWD duration and induced continuous SWDs up to 26 min. Following the initial absence status event, sleep was induced; then, the second period of absence status-like activities were initiated. ETX pretreatment blocked the occurrence of absence status-like activities. Power spectral density analyses revealed that DEX-induced post-sleep activities had higher power in delta frequency band (1-4 Hz) and attenuated power of 7 Hz harmonics (14 and 21 Hz) than the pre-injection seizure. The mean duration of SWDs were decreased in all the groups, but occasional prolonged activities were seen in ETX or VPA-injected rats but not with DIAZ or ATI.

SIGNIFICANCE

This study presents an absence status epilepticus animal model that is activated by α2AR activation to investigate the pathophysiological role of absence status. Unlike other agents ATI switched off the second set of absence statuses to normal SWDs, without sedation or lethargy, can show it may preferentially block absence status-like activity.

THE PLAIN LANGUAGE SUMMARY

This study proposes a rat model for prolonged seizures, resembling absence status epilepticus. Activating the brain's alpha-2a adrenergic receptor with dexmedetomidine induced seizures lasting up to 26 minutes. Ethosuximide pretreatment and post-treatment with valproic acid, diazepam, and atipamezole decreased induced seizures. The findings suggest this model is valuable for studying absence status epilepticus. In addition, atipamezole normalized abnormal seizures without sedation, hinting at its potential for targeted treatment and further research.

Nonconvulsive Status Epilepticus With Generalized Spike-and-Wave Discharges: Pathophysiological and Nosological Considerations

Absence status epilepticus (ASE) is the most common type of status epilepticus in patients with idiopathic generalized epilepsy (IGE). Like absence seizure, ASE is characterized by generalized spike-and-wave discharges (GSWDs) on the electroencephalogram (EEG). Once considered specific for IGE, GSWDs have increasingly been observed in other forms of epilepsy, as well as in patients with no prior epilepsy. Here, we report three patients with different types of nonconvulsive status epilepticus (NCSE) in which the EEG correlate was GSWDs: a 44-year-old woman with juvenile absence epilepsy who manifested ASE, a 73-year-old woman with anoxic brain injury complicated by NCSE with well-formed GSWDs (as seen in IGE and de novo ASE), and a 41-year-old woman with frontal lobe epilepsy who developed focal NCSE with impaired consciousness. Evidently, patients with generalized epilepsy, focal epilepsy, and no prior epilepsy can all manifest NCSE with similar electroclinical characteristics, i.e., GSWDs and impaired consciousness. This observation adds to the existing evidence that seizures, whether classified as focal or generalized, often involve focal and generalized elements in their pathophysiology. To fully understand seizure pathophysiology, we must steer away from the focal-versus-generalized paradigm that has dominated the nosology of seizures and epilepsy for a very long time.

Pediatric Ovarian Torsion: Should You Go With the Flow?

OBJECTIVES

Ovarian torsion (OT) is an emergency that mandates early detection and surgical detorsion to avoid catastrophic consequences of further adnexal injury. Prompt ultrasound is critical for accurate diagnosis. Traditionally, evaluation of arterial and venous flow was used as a diagnostic tool for OT, but recent radiologic research has indicated that ovarian size and size discrepancy between sides is a better diagnostic criterion. This study seeks to determine whether ovarian size discrepancy or vascular flow to the ovary is more accurate in the diagnosis of OT in the pediatric emergency population and to better describe symptoms that distinguish OT from other abdominal and pelvic pathology.

METHODS

This was a retrospective, cross-sectional study evaluating all female pediatric patients, aged 1 to 18 years, who underwent a pelvic ultrasound to evaluate for OT over a 2-year period in our pediatric emergency department. Patients suitable for inclusion were identified via Nuance mPowerTM, a search engine that provides clinical analytics based on radiology reports generated within our institution.

RESULTS

We reviewed the medical records of 193 female patients aged 1 to 18 years, all of whom had a pelvic ultrasound (with or without Doppler) to evaluate for OT during the study period. In comparing ovarian size on ultrasound, patients with OT had a significantly larger magnitude of difference in ovarian volume than patients without torsion (5.57× [interquartile range, 3-12.5] vs 1.56× [interquartile range, 1.24-2.25; P < 0.001]). Ovarian torsion was associated with a 33-fold increased risk of lack of arterial flow (relative risk, 33.33) and with a 9-fold increased risk of lack of venous flow (relative risk, 9.27), when compared with those patients without OT. Patients with OT were significantly more likely to have emesis and peritoneal signs on examination, as well as previous history of OT (P = 0.01, 0.02, and 0.002, respectively) than those without OT. All patients with OT reported abdominal pain.

CONCLUSIONS

We found that a large size discrepancy between ovaries is indicative of OT. Our data also suggest that presence of Doppler flow on ultrasound cannot be used to exclude OT but that lack of Doppler flow on ultrasound is a significant diagnostic marker. As previous studies have also found, clinical symptoms of OT are nonspecific and do not offer any certainty in differentiating OT from other pathologies.

Typical absence status epilepticus in older people: syndromic delineation

Objective We describe the clinical, electroencephalograph^ and neuroimaging findings of older patients with typical absence status epilepticus (ASE). Methods This investigation was a retrospective analysis of prospectively collected consecutive patients between January 2011 and October 2021. All patients ≥60 years with impairment of awareness and continuous generalized, rhythmic, synchronous and symmetric epileptiform discharges and normal background on video-electroencephalogram (vEEG) were included. Results Six patients were identified with a diagnosis of typical ASE. The mean age was 67 years. Five could be classified as idiopathic generalized epilepsy (IGE) though two had been erroneously categorized as cryptogenic focal epilepsy (FE). In one, the episode of ASE was thought to represent the beginning of late-onset IGE (de novo late-onset typical ASE). In all cases, ASE was controlled within the first 24 hours. Significance Typical ASE is a rare cause of confusion in the elderly population requiring urgent vEEG evaluation. It most frequently represents reactivation of a previous IGE, in effect related to patients with epilepsy with onset in childhood or adolescence, not previously diagnosed or treated, representing rather the debut of (de novo) late-onset IGE.

Dazed and Confused: Altered Mental Status in an Adolescent Male

BACKGROUND

Absence status epilepticus (ASE) is a form of generalized nonconvulsive status epilepticus. ASE is characterized by impairment in consciousness, which can vary widely, making the diagnosis more difficult. The typical patient with ASE will be confused yet responsive and in a "trance-like state" with delayed speech, clumsy gait, and the ability to perform simple tasks after prompting. With treatment, typical ASE has an excellent prognosis and does not appear to be associated with significant neuronal damage.

CASE PRESENTATION

An 11-year-old boy with history of febrile seizures presented to the emergency department (ED) with altered mental status without trauma or ingestion. His vital signs and physical examination were normal, with the exception of appearing intoxicated with sparse verbalization and inappropriate emotional responses. All laboratory results and imaging were unremarkable. While in the ED, his neurologic examination trended toward normal, returning almost to baseline. He was admitted to the hospital for video electroencephalogram, which revealed status epilepticus. After benzodiazepine therapy, epileptic electrical activity ceased and the patient's symptoms resolved. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: ASE is a rare condition that is uncommonly described in the pediatric population. These patients are frequently misdiagnosed on initial presentation as their alteration in mental status can be easily confused with ingestion, trauma, psychiatric illness, or infectious etiologies. Overturning the long-standing emergency dogma of "if they're talking to you, it's not a seizure" is undoubtedly difficult, but both pediatric and adult providers should be aware of this clinical entity.