AERRPS, DESC, NORSE, FIRES: multi-labeling or distinct epileptic entities?

Rapid onset of hippocampal atrophy in febrile-infection related epilepsy syndrome (FIRES)

Febrile infection-related epilepsy syndrome (FIRES) is a catastrophic and usually refractory epilepsy syndrome that occurs after a febrile illness in previously normal children. The pathogenesis of the syndrome is unknown, and the diagnosis is typically made by exclusion after an exhaustive negative workup for central nervous system infections and autoimmune or metabolic disorders. Magnetic resonance imaging of patients with this condition has previously shown hippocampal abnormalities, typically found several months or longer after initial seizures. We report a previously healthy 5-year-old child who developed hippocampal atrophy by day 37 of his illness. The development of early hippocampal atrophy in this epileptic encephalopathy may provide insight into pathogenesis and highlights the need for aggressive and effective interventions early in the disease process.

Successful surgical treatment of an inflammatory lesion associated with new-onset refractory status epilepticus

New-onset refractory status epilepticus (NORSE) has high morbidity and mortality. The authors describe the successful surgical treatment of a 56-year-old man presenting with NORSE. Magnetic resonance imaging showed a left temporal lobe lesion suspicious for a low-grade tumor, while PET imaging with the alpha[(11)C]methyl-L-tryptophan (AMT) radiotracer showed increased cortical uptake extending beyond this lesion and partly overlapping with epileptogenic cortex mapped by chronic intracranial electroencephalographic monitoring. Resection of the epileptic focus resulted in long-term seizure freedom, and the nonresected portion of the PET-documented abnormality normalized. Histopathology showed reactive gliosis and inflammatory markers in the AMT-PET-positive cortex. Molecular imaging of neuroinflammation can be instrumental in the management of NORSE by guiding placement of intracranial electrodes or assessing the extent and severity of inflammation for antiinflammatory interventions.

Ketogenic diet in 3 cases of childhood refractory status epilepticus

INTRODUCTION

Refractory status epilepticus (RSE) in children is associated with a significant risk of death or neurological morbidity. Recently attention has been drawn to the ketogenic diet (KD) as an acute treatment, as it has shown promise in controlling seizures in otherwise refractory status epilepticus in several cases. We have listed these and reviewed all cases of KD used in RSE at our centre. KD was given as 4:1 fat:carbohydrate-protein solution.

RESULTS

A 3-year-old girl with RSE due to Hemiconvulsion-Hemiplegia Epilepsy syndrome. KD was instigated on day 6. Seizures stopped with ketosis on day 7. A 10-year-old boy rapidly developing RSE. After months a mitochondrial disorder was discovered. KD was tried twice with severe side-effects but no seizure control. 11-year-old healthy boy with RSE as FIRES. On KD seizures stopped for 24 h one day after reaching ketosis. He improved over 3-4 weeks.

DISCUSSION

KD was efficient in two of three cases of RSE. The non-responder had severe side-effects and proved to have a mitochondrial disorder which is arguably a contraindication for KD. More studies are needed to prove efficacy of KD in RSE, to define optimal timing of KD and possible contraindications for KD in RSE.

New-onset refractory status epilepticus mimicking herpes virus encephalitis

New-onset refractory status epilepticus (NORSE) is a recently defined clinical entity that describes patients who present with status epilepticus of unclear etiology that is highly refractory to therapy. Magnetic resonance imaging (MRI) of NORSE usually discloses no specific abnormalities except for an occasional mild T2/FLAIR hyperintense signal of the mesial temporal lobe. Here, we report a peculiar case of NORSE in which brain MRI showed massive alteration of both temporal lobes, with features strongly supporting the diagnosis of herpes virus encephalitis, but lacking any laboratory evidence of viral infection in the blood and cerebrospinal fluid. It showed also striking signal alterations in the thalamus, which got worse in the course of the disease. This report emphasizes the possibility that seizure activity alone plays a critical role in both determining the disease and whether it will be self-sustaining.

Use of dietary therapy for status epilepticus

One of the newest and yet fastest growing indications for dietary therapy is the emergency treatment of refractory status epilepticus. Ten retrospective publications since 2008 have reported benefits in 32 children and adults, of whom 25 (78%) became seizure-free. Most of the patients who responded did so within 7 to 10 days of the initiation of nasogastrically administered ketogenic formulas. Encephalitis and febrile-illness related epilepsy syndrome causing status epilepticus highly refractory to antiepileptic drugs may be particularly amenable to dietary treatment. Prospective, multicenter studies are under way to help clarify who best will respond, how quickly, and the optimal diet duration after success.

Pediatric intensive care treatment of uncontrolled status epilepticus

The critically ill mechanically ventilated child with ongoing seizures that are refractory to any treatment presents a distinct challenge in pediatric neurocritical care. The evidence base from randomized controlled trials on which anti-epileptic drug (AED) strategy should be used is inadequate. This review of refractory and super-refractory status epilepticus summarizes recent pediatric case series regarding definitions, the second-tier AED therapies once initial anticonvulsants have failed, and the experience of high-dose midazolam, barbiturate anesthesia, and volatile anesthetics for uncontrolled status epilepticus.