A case of clinical worsening after stereo-electroencephalographic-guided radiofrequency thermocoagulation in a patient with polymicrogyria

: Radiofrequency thermocoagulation (RF-TC) is a wide-used procedure for drug-resistant epilepsy. The technique is considered safe with an overall risk of 1.1% of permanent complications, mainly focal neurological deficits. We report the case of a patient with drug-resistant epilepsy who complained of immediate seizure worsening and an unexpected event seven months following RF-TC. A 35-year-old male with drug-resistant epilepsy from the age of 18 years underwent stereoelectroencephalography (SEEG) implantation for a right peri-silvian polymicrogyria. He was excluded from surgery due to extent of the epileptogenic zone and the risk of visual field deficits. RF-TC was attempted to ablate the most epileptogenic zone identified by SEEG. After RF-TC, the patient reported an increase in seizure severity/frequency and experienced episodes of postictal psychosis. Off-label cannabidiol treatment led to improved seizure control and resolution of postictal psychosis. Patients with polymicrogyria (PwP) may present with a disruption of normal anatomy and the co-existence between epileptogenic zone and eloquent cortex within the malformation. RF-TC should be considered in PwP when they are excluded from surgery for prognostic and palliative purposes. However, given the complex interplay between pathological and electrophysiological networks in these patients, the remote possibility of clinical exacerbation after RF-TC should also be taken into account

Association of the mtDNA m.4171C>A/MT-ND1 mutation with both optic neuropathy and bilateral brainstem lesions

Background: An increasing number of mitochondrial DNA (mtDNA) mutations, mainly in complex I genes, have been associated with variably overlapping phenotypes of Leber’s hereditary optic neuropathy (LHON), mitochondrial encephalomyopathy with stroke-like episodes (MELAS) and Leigh syndrome (LS). We here describe the first case in which the m.4171C>A/MT-ND1 mutation, previously reported only in association with LHON, leads also to a Leigh-like phenotype. Case presentation: A 16-year-old male suffered subacute visual loss and recurrent vomiting and vertigo associated with bilateral brainstem lesions affecting the vestibular nuclei. His mother and one sister also presented subacute visual loss compatible with LHON. Sequencing of the entire mtDNA revealed the homoplasmic m.4171C>A/MT-ND1 mutation, previously associated with pure LHON, on a haplogroup H background. Three additional non-synonymous homoplasmic transitions affecting ND2 (m.4705T>C/MT-ND2 and m.5263C>T/MT-ND2) and ND6 (m.14180T>C/MT-ND6) subunits, well recognized as polymorphisms in other mtDNA haplogroups but never found on the haplogroup H background, were also present. Conclusion: This case widens the phenotypic expression of the rare m.4171C>A/MT-ND1 LHON mutation, which may also lead to Leigh-like brainstem lesions, and indicates that the co-occurrence of other ND non-synonymous variants, found outside of their usual mtDNA backgrounds, may have increased the pathogenic potential of the primary LHON mutation

GWAS meta-analysis of over 29,000 people with epilepsy identifies 26 risk loci and subtype-specific genetic architecture

Epilepsy is a highly heritable disorder affecting over 50 million people worldwide, of which about one-third are resistant to current treatments. Here we report a multi-ancestry genome-wide association study including 29,944 cases, stratified into three broad categories and seven subtypes of epilepsy, and 52,538 controls. We identify 26 genome-wide significant loci, 19 of which are specific to genetic generalized epilepsy (GGE). We implicate 29 likely causal genes underlying these 26 loci. SNP-based heritability analyses show that common variants explain between 39.6% and 90% of genetic risk for GGE and its subtypes. Subtype analysis revealed markedly different genetic architectures between focal and generalized epilepsies. Gene-set analyses of GGE signals implicate synaptic processes in both excitatory and inhibitory neurons in the brain. Prioritized candidate genes overlap with monogenic epilepsy genes and with targets of current antiseizure medications. Finally, we leverage our results to identify alternate drugs with predicted efficacy if repurposed for epilepsy treatment

Epileptic and developmental encephalopathies: clinical and genetic study of adult patients attending a tertiary Epilepsy Centre

Objectives: To fully re-evaluate patients with early-onset epilepsy and intellectual disability with neurological, neurophysiological and neuropsychological examination in order to contribute to expanding the phenotypic spectrum of known epileptic encephalopathy (EE)-related genes and to identify novel genetic defects underlying EEs. Methods: We recruited patients with epilepsy and intellectual disability (ID) referring to our Epilepsy Centre. Patients underwent full clinical and neurophysiologic evaluation. When possible they underwent neuroradiologic investigations. Selected cases also underwent genetic analysis. Results: We recruited 200 patients (109 M, 91 F; mean age 36 years old). Mean age at epilepsy onset was 4 years old. The degree of ID was borderline in 4.5% of patients, mild in 25%, moderate in 38% and severe in 32.5%. EEG showed epileptiform abnormalities in 79.5% of patients. One hundred and thirty-one patients out of the 200 recruited (65.5%) did not have an aetiological diagnosis. All the patients underwent full clinical reassessment and when necessary they performed neuroradiologic and genetic investigations as well. We identified 35 patients with a genetic aetiology. In 8 cases a structural brain lesion was observed. In 33 patients, a genetic aetiology was identified. In 2 patients with drug-resistant seizures video-EEG allowed the identification of non-epileptic seizures, and in one patient we discontinued anti-epileptic drugs. In these patients, the aetiological diagnosis was made after 30 years (range 9-60 years) from the disease onset. Conclusions: In a population of 200 adult patients with epilepsy and ID, an aetiological cause was identified in 45 patients after 30 years from the disease onset. Aetiological diagnosis, especially if genetic, has significant positive implications for patients, even if it has been made after years from the beginning of the disease. Benefits include better-focused antiepileptic drug (AED) choice, sparing of further unnecessary investigations and improved knowledge of comorbidities

Juvenile absence epilepsy relapsing as recurrent absence status, mimicking transient global amnesia, in an elderly patient

We describe a 68-year-old woman who had typical absence seizures since 14 years of age. The absences were refractory to treatment and persisted into adulthood, with no seizure-free periods until seizure control at 59 years of age. After six years of being seizure-free, she presented with an episode characterized by mental confusion, abnormal behaviour, and amnesia, lasting for several hours. An EEG performed the day after, when the patient had already recovered, was unremarkable. The episode was interpreted as transient global amnesia. After two and three years, respectively, she presented with two analogous episodes lasting >24 hours. An EEG disclosed, on both occasions, subcontinuous generalized spike-and-wave discharges, consistent with absence status epilepticus (AS). The last episode occurred at 68 years of age and was successfully treated with intravenous lorazepam. After one month of follow-up, no further episodes occurred. AS is common in juvenile absence epilepsy, however, our patient showed a rather atypical course, characterized by refractory and persistent absences during adolescence and adulthood, and a tendency for AS to recur with no more absences in later life. Despite the known epilepsy history, AS episodes were initially misdiagnosed. Moreover, EEG recording and subsequent treatment were not performed until the second day of status

Semiological study of ictal affective behaviour in epilepsy and mental retardation limited to females (EFMR)

Epilepsy and mental retardation limited to females (EFMR) is a genetic disorder that affects females but spares transmitting males. The condition is caused by protocadherin 19 mutations and is characterised by seizures beginning at around 1 year of age, frequently associated with cognitive regression at seizure onset or later. Seizures can be generalised or focal, exacerbated by febrile illnesses, and grouped in clusters. This report shows the first video-EEG recording of EFMR, in a 7-year-old female presenting peculiar ictal features. [Published with video sequences

Semiological study of ictal affective behaviour in epilepsy and mental retardation limited to females (EFMR)

Epilepsy and mental retardation limited to females (EFMR) is a genetic disorder that affects females but spares transmitting males. The condition is caused by protocadherin 19 mutations and is characterised by seizures beginning at around 1 year of age, frequently associated with cognitive regression at seizure onset or later. Seizures can be generalised or focal, exacerbated by febrile illnesses, and grouped in clusters. This report shows the first video-EEG recording of EFMR, in a 7-year-old female presenting peculiar ictal features. [Published with video sequences

Cerebral areas involved in music perception: studying musicogenic epilepsy.

Functional cerebral areas involved in listening to emotionally charged music are wider than those activated by neutral music. Based on the pathophysiology of musicogenic epilepsy, a rare form of complex reflex epilepsy in which seizures are triggered by music, we can infer the functional organization of the brain's processing of music. We studied a 36-year-old, right-handed male amateur musician, who has had weekly epileptic partial seizures every time he listened to or played music with a strong emotional charge since the age of 24 years. The patient underwent prolonged video-polygraphic recording which documented three right temporal seizures preceded for several seconds by an increase in heart rate and blood pressure, all triggered by listening to music with an emotional content. During functional neuroimaging (fMRI) he listened to both "neutral" and "emotionally charged" music. The “neutral music” activated only a small eloquent area in the right temporal lobe (acoustic area), whereas an “emotionally charged melody" activated diffuse eloquent areas on the fronto-temporo-occipital lobes of the right hemisphere before seizure onset. Numerous studies have demonstrated the predominant involvement of right hemisphere structures in networks involved in processing musical information. Most cases of musicogenic epilepsy showed the dominant role of the right temporal lobe disclosed by functional neuroimaging and neurophysiological techniques. The triggering stimulus in our patient seems to be a strong emotional feeling induced by specific melodies, as his seizures were preceded by an increase in heart rate and blood pressure. Our results emphasize the role of the right temporal lobe in musicogenic epilepsy and show that the cerebral areas activated during the emotional status leading to seizures encompass the auditory cortex activated by neutral music

Phenotype variability of GLUT1 deficiency syndrome: Description of a case series with novel SLC2A1 gene mutations

Glucose transporter type 1 (GLUT1) deficiency due to SLC2A1 mutations causes a wide spectrum of neurologic disorders ranging from severe encephalopathy with developmental delay, epilepsy, ataxia, and acquired microcephaly to atypical less severe variants. Early diagnosis is crucial for prompt initiation of a ketogenic diet. Recognizing GLUT1 deficiency syndrome (GLUT1DS) may be challenging and results in delayed diagnosis. Here we describe the clinical and molecular findings of patients with SLC2A1 mutations referred to our adult Epilepsy Center. Patients with a clinical history suggestive of GLUT1DS were screened for SLC2A1 mutations. Blood samples were collected from probands and first-degree relatives. A lumbar puncture was performed in two patients in fasting state, and cerebrospinal fluid and blood glucose measurement were undertaken at the same time. Since 2010, 19 GLUT1DS probands have been screened for SLC2A1 mutations. We identified four different SLC2A1 mutations in three sporadic cases and one family. Three mutations (c.130_135delTACAAC, c.342_343insA, and c.845A > G) were novel, whereas one was previously reported in the literature associated with a different phenotype (c.497_499delTCG). Here we describe a small case series of patients with sporadic and familial GLUT1DS presenting with a broad phenotypic heterogeneity which is likely to be responsible for the considerable delay in diagnosis

Pearls & Oy-sters: rapidly progressive dementia: prions or immunomediated?

The paper presentes a case report of a patient with rapidly progressive dementia. The discussion is focused on the differential diagnosis between Voltage-gated potassium channel antibody\u2013associated encephalitis and sporadic Creutzfeldt-Jakob disease