KCNQ2 encephalopathy manifesting with Rett-like features: A follow-up into adulthood.
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ABSTRACT:
SUBMITTER: Mastrangelo M
PROVIDER: S-EPMC7577543 | biostudies-literature | 2020 Oct
REPOSITORIES: biostudies-literature
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KCNQ2 encephalopathy manifesting with Rett-like features: A follow-up into adulthood.
Mastrangelo Mario M Manti Filippo F Giannini Maria Teresa MT Guerrini Renzo R Leuzzi Vincenzo V
Neurology. Genetics 20200908 5
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Project description:ObjectiveTo advance the understanding of KCNQ2 encephalopathy genotype-phenotype relationships and to begin to assess the potential of selective KCNQ channel openers as targeted treatments.MethodsWe retrospectively studied 23 patients with KCNQ2 encephalopathy, including 11 treated with ezogabine (EZO). We analyzed the genotype-phenotype relationships in these and 70 previously described patients.ResultsThe mean seizure onset age was 1.8 ± 1.6 (SD) days. Of the 20 EEGs obtained within a week of birth, 11 showed burst suppression. When new seizure types appeared in infancy (15 patients), the most common were epileptic spasms (n = 8). At last follow-up, seizures persisted in 9 patients. Development was delayed in all, severely in 14. The KCNQ2 variants identified introduced amino acid missense changes or, in one instance, a single residue deletion. They were clustered in 4 protein subdomains predicted to poison tetrameric channel functions. EZO use (assessed by the treating physicians and parents) was associated with improvement in seizures and/or development in 3 of the 4 treated before 6 months of age, and 2 of the 7 treated later; no serious side effects were observed.ConclusionsKCNQ2 variants cause neonatal-onset epileptic encephalopathy of widely varying severity. Pathogenic variants in epileptic encephalopathy are clustered in "hot spots" known to be critical for channel activity. For variants causing KCNQ2 channel loss of function, EZO appeared well tolerated and potentially beneficial against refractory seizures when started early. Larger, prospective studies are needed to enable better definition of prognostic categories and more robust testing of novel interventions.Classification of evidenceThis study provides Class IV evidence that EZO is effective for refractory seizures in patients with epilepsy due to KCNQ2 encephalopathy.
| S-EPMC4995058 | biostudies-literature
Project description:ObjectiveKCNQ2-associated developmental and epileptic encephalopathies (DEE) present with seizures and developmental impairments. The relation between seizures and functional impairments in affected children and the relation of a specific genetic variant to seizure control remains unknown.MethodsParents of children with documented KCNQ2 variants who participated in a structured, online natural history survey provided information about seizure history, functional mobility, hand use, communication function, and feeding independence. Bivariate analyses were performed with nonparametric methods and logistic regression was used for multivariable analyses.ResultsThirty-nine children (20, 51% girls, median age 4.5 years, interquartile range (IQR) 1.9-19.3) had a median age of seizure onset of 1 day (IQR 1-3 days). The most common seizure types were bilateral tonic-clonic (N = 72, 28%) and bilateral tonic (N = 13, 33%). Time since last seizure was <6 months (N = 18, 46%), 6-23 months (N = 11, 28%), and ≥24 months (N = 10 26%). Severe functional impairment was reported for mobility (62%), hand grasp (31%), feeding (59%), and communication (77%). Twenty-eight (72%) were impaired in ≥2 domains. There were only weak and inconsistent associations between seizure recency and individual impairments or number of impairments after adjustment for other factors. The functional location of the variants within the Kv 7.2 protein was not associated with seizure control.InterpretationSeizures in KCNQ2-DEE are often well-controlled, but children have severe impairments regardless. With the increased potential for precision therapies targeting the Kv 7.2 channel or the KCNQ2 gene itself, identifying the most relevant and sensitive clinical endpoints will be critical to ensure successful trials of new therapies.
| S-EPMC7951099 | biostudies-literature
Project description:Sarcoidosis + Follow-up 6 month after Keywords = sarcoidosis Keywords = follow-up Keywords: other
2005-01-18 | GSE1907 | GEO
Project description:BackgroundNeonatal convulsions are clinical manifestations in a heterogeneous group of disorders with different etiology and outcome. They are attributed to several genetic causes.MethodsWe describe a patient with intractable neonatal seizures who died from respiratory compromise during a status epilepticus.ResultsThis case report provides electroencephalogram (EEG), MRI, genetic analysis, and neuropathological data. Genetic analysis revealed a de novo heterozygous missense mutation in the KCNQ2 gene, which encodes a subunit of a voltage-gated potassium channel. KCNQ2 gene mutation is associated with intractable neonatal seizures. EEG, MRI, data as well as mutation analysis have been described in other KCNQ2 cases. Post-mortem neuropathological investigation revealed mild malformation of cortical development with increased heterotopic neurons in the deep white matter compared to an age-matched control subject. The new finding of this study is the combination of a KCNQ2 mutation and the cortical abnormalities.ConclusionKCNQ2 mutations should be considered in neonates with refractory epilepsy of unknown cause. The mild cortical malformation is an important new finding, though it remains unknown whether these cortical abnormalities are due to the KCNQ2 mutation or are secondary to the refractory seizures.
| S-EPMC4271583 | biostudies-literature
Project description:Fecal microbiota profiles of growing pigs on three Finnish farms
| PRJEB70954 | ENA
Project description:Background: Pediatric systemic lupus erythematosus (pSLE) is a rare condition, representing approximately 10% of SLE cases. The aim of this study was to identify variables to improve the diagnostic awareness and management of pSLE patients. Methods: This retrospective study included 25 patients diagnosed with pSLE and followed at the University of Pisa. We collected data about clinical profile at disease onset and during a long-term follow-up, including disease activity, organ damage development, and treatments received. Results: The mean patient age at disease onset was 14.6 ± 1.6 years, and the mean follow-up period was 14.17 ± 8.04 years. The most common initial manifestations were arthritis, malar rash, and cytopenias. The median time to diagnosis since the first symptoms was 6 months, and was significantly longer in patients with hematological onset (54 months). During follow-up, the number of patients with renal involvement showed a significant increase, from 36% at diagnosis to 72.2% after 10 years of disease evolution. Patients who developed chronic organ damage maintained a higher time-averaged disease activity during follow-up and received a significantly higher dose of corticosteroids. Conclusion: Patients with immune cytopenia represent a group deserving strict clinical follow-up for the risk of evolution to SLE. Intense surveillance of renal function, early treatment and steroid-sparing strategies should be strongly considered in the management of pSLE patients.
| S-EPMC5964827 | biostudies-literature
Project description:Neonatal-onset epilepsies are rare conditions, mostly genetically determined, that can have a benign or severe phenotype.(1,2) There is recent recognition of de novo KCNQ2 mutations in patients with severe neonatal-onset epilepsy with intractable seizures and severe psychomotor impairment, termed KCNQ2 encephalopathy.(3,4) This is a rare condition and all patients reported so far were diagnosed well after the neonatal period.(3,4) We report on 3 new cases of KCNQ2 encephalopathy diagnosed in the neonatal period and studied with continuous video-EEG recording. We describe a distinct electroclinical phenotype and report on efficacy of antiepileptic drug (AED) therapies.
| S-EPMC3929196 | biostudies-literature
Project description:BackgroundTypical patients with KCNQ2 (OMIM# 602235) epileptic encephalopathy present early neonatal-onset intractable seizures with a burst suppression EEG pattern and severe developmental delay or regression, and those patients always fail first-line treatment with sodium channel blockers. Vitamin B6, either pyridoxine or pyridoxal 50-phosphate, has been demonstrated to improve seizure control in intractable epilepsy.MethodsHere, we collected and summarized the clinical data for four independent cases diagnosed with pyridoxine-responsive epileptic encephalopathy, and their exome sequencing data. Moreover, we reviewed all published cases and summarized the clinical features, genetic variants, and treatment of pyridoxine-responsive KCNQ2 epileptic encephalopathy.ResultsAll four cases showed refractory seizures during the neonatal period or infancy, accompanied by global development delay. Four pathogenetic variants of KCNQ2 were uncovered and confirmed by Sanger sequencing: KCNQ2 [NM_172107.4: c.2312C > T (p.Thr771Ile), c.873G > C (p.Arg291Ser), c.652 T > A (p.Trp218Arg) and c.913-915del (p. Phe305del)]. Sodium channel blockers and other anti-seizure medications failed to control their seizures. The frequency of seizures gradually decreased after treatment with high-dose pyridoxine. In case 1, case 2, and case 4, clinical seizures relapsed when pyridoxine was withdrawn, and seizures were controlled again when pyridoxine treatment was resumed.ConclusionOur study suggests that pyridoxine may be a promising adjunctive treatment option for patients with KCNQ2 epileptic encephalopathy.
| S-EPMC9544210 | biostudies-literature
Project description:Kv7 channels are enriched at the axonal plasma membrane where their voltage-dependent potassium currents suppress neuronal excitability. Mutations in Kv7.2 and Kv7.3 subunits cause epileptic encephalopathy (EE), yet the underlying pathogenetic mechanism is unclear. Here, we used novel statistical algorithms and structural modeling to identify EE mutation hotspots in key functional domains of Kv7.2 including voltage sensing S4, the pore loop and S6 in the pore domain, and intracellular calmodulin-binding helix B and helix B-C linker. Characterization of selected EE mutations from these hotspots revealed that L203P at S4 induces a large depolarizing shift in voltage dependence of Kv7.2 channels and L268F at the pore decreases their current densities. While L268F severely reduces expression of heteromeric channels in hippocampal neurons without affecting internalization, K552T and R553L mutations at distal helix B decrease calmodulin-binding and axonal enrichment. Importantly, L268F, K552T, and R553L mutations disrupt current potentiation by increasing phosphatidylinositol 4,5-bisphosphate (PIP2), and our molecular dynamics simulation suggests PIP2 interaction with these residues. Together, these findings demonstrate that each EE variant causes a unique combination of defects in Kv7 channel function and neuronal expression, and suggest a critical need for both prediction algorithms and experimental interrogations to understand pathophysiology of Kv7-associated EE.
| S-EPMC7075958 | biostudies-literature