1
|
Medina Lemus A, Boelman C, Myers KA. Epilepsy in Legius syndrome: Coincidence or causation? Am J Med Genet A 2024; 194:e63547. [PMID: 38268057 DOI: 10.1002/ajmg.a.63547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/10/2024] [Accepted: 01/13/2024] [Indexed: 01/26/2024]
Abstract
Legius syndrome is a rare genetic disorder, caused by heterozygous SPRED1 pathogenic variants, which shares phenotypic features with neurofibromatosis type 1 (NF1). Both conditions typically involve café-au-lait macules, axillary freckling, and macrocephaly; however, patients with NF1 are also at risk for tumors, such as optic nerve gliomas and neurofibromas. Seizure risk is known to be elevated in NF1, but there has been little study of this aspect of Legius syndrome. The reported epilepsy incidence is 3.3%-5%, well above the general population incidence of ~0.5%-1%, but the few reports in the literature have very little data regarding epilepsy phenotype. We identified two unrelated individuals, both with Legius syndrome and epilepsy, and performed thorough phenotyping. One individual's mother also had Legius syndrome and now-resolved childhood epilepsy, as well as reports of more distant relatives who also had multiple café-au-lait macules and seizures. Both probands had experienced childhood-onset focal seizures, with normal brain MRI. In one patient, EEG later showed apparently generalized epileptiform abnormalities. Based on the data from this small case series and literature review, seizure risk is increased in people with Legius syndrome, but the epilepsy prognosis appears to be generally good, with patients having either self-limited or pharmacoresponsive courses.
Collapse
Affiliation(s)
- Adalbeis Medina Lemus
- Division of Neurology, Department of Pediatrics, Montreal Children's Hospital, McGill University Health Centre, Montreal, Quebec, Canada
| | - Cyrus Boelman
- Division of Neurology, Department of Pediatrics, British Columbia Children's Hospital, Vancouver, British Columbia, Canada
| | - Kenneth A Myers
- Division of Neurology, Department of Pediatrics, Montreal Children's Hospital, McGill University Health Centre, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
- Department of Neurology and Neurosurgery, Montreal Children's Hospital, McGill University Health Centre, Montreal, Quebec, Canada
| |
Collapse
|
2
|
Rodrigo Marinowic D, Bottega Pazzin D, Prates da Cunha de Azevedo S, Pinzetta G, Victor Machado de Souza J, Tonon Schneider F, Thor Ramos Previato T, Jean Varella de Oliveira F, Costa Da Costa J. Epileptogenesis and drug-resistant in focal cortical dysplasias: Update on clinical, cellular, and molecular markers. Epilepsy Behav 2024; 150:109565. [PMID: 38070410 DOI: 10.1016/j.yebeh.2023.109565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 11/24/2023] [Accepted: 11/26/2023] [Indexed: 01/14/2024]
Abstract
Focal cortical dysplasia (FCD) is a cortical malformation in brain development and is considered as one of the major causes of drug-resistant epilepsiesin children and adults. The pathogenesis of FCD is yet to be fully understood. Imaging markers such as MRI are currently the surgeons major obstacle due to the difficulty in delimiting the precise dysplasic area and a mosaic brain where there is epileptogenic tissue invisible to MRI. Also increased gene expression and activity may be responsible for the alterations in cell proliferation, migration, growth, and survival. Altered expressions were found, particularly in the PI3K/AKT/mTOR pathway. Surgery is still considered the most effective treatment option, due to drug-resistance, and up to 60 % of patients experience complete seizure control, varying according to the type and location of FCD. Both genetic and epigenetic factors may be involved in the pathogenesis of FCD, and there is no conclusive evidence whether these alterations are inherited or have an environmental origin.
Collapse
Affiliation(s)
- Daniel Rodrigo Marinowic
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil; Graduate Program in Medicine and Health Sciences, School of Medicine, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil.
| | - Douglas Bottega Pazzin
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil; Graduate Program in Medicine and Health Sciences, School of Medicine, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Giulia Pinzetta
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - João Victor Machado de Souza
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Fernando Tonon Schneider
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Thales Thor Ramos Previato
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil; Graduate Program in Medicine and Health Sciences, School of Medicine, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Fábio Jean Varella de Oliveira
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil; Graduate Program in Medicine and Health Sciences, School of Medicine, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Jaderson Costa Da Costa
- Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil; Graduate Program in Medicine and Health Sciences, School of Medicine, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| |
Collapse
|
3
|
Checri R, Chipaux M, Ferrand-Sorbets S, Raffo E, Bulteau C, Rosenberg SD, Doladilhe M, Dorfmüller G, Adle-Biassette H, Baldassari S, Baulac S. Detection of brain somatic mutations in focal cortical dysplasia during epilepsy presurgical workup. Brain Commun 2023; 5:fcad174. [PMID: 37324239 PMCID: PMC10261848 DOI: 10.1093/braincomms/fcad174] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 04/01/2023] [Accepted: 05/31/2023] [Indexed: 06/17/2023] Open
Abstract
Brain-restricted somatic variants in genes of the mechanistic target of rapamycin signalling pathway cause focal epilepsies associated with focal cortical dysplasia type II. We hypothesized that somatic variants could be identified from trace tissue adherent to explanted stereoelectroencephalography electrodes used in the presurgical epilepsy workup to localize the epileptogenic zone. We investigated three paediatric patients with drug-resistant focal epilepsy subjected to neurosurgery. In the resected brain tissue, we identified low-level mosaic somatic mutations in AKT3 and DEPDC5 genes. We collected stereoelectroencephalography depth electrodes in the context of a second presurgical evaluation and identified 4/33 mutation-positive electrodes that were either located in the epileptogenic zone or at the border of the dysplasia. We provide the proof-of-concept that somatic mutations with low levels of mosaicism can be detected from individual stereoelectroencephalography electrodes and support a link between the mutation load and the epileptic activity. Our findings emphasize future opportunities for integrating genetic testing from stereoelectroencephalography electrodes into the presurgical evaluation of refractory epilepsy patients with focal cortical dysplasia type II to improve the patients' diagnostic journey and guide towards precision medicine.
Collapse
Affiliation(s)
| | | | - Sarah Ferrand-Sorbets
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
| | - Emmanuel Raffo
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
- Unité de recherche 3450 DevAH, Développement, Adaptation et Handicap, Campus Brabois-Santé, Université de Lorraine, 54505, Vandoeuvre-lès-Nancy, France
| | - Christine Bulteau
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
- Université de Paris Cité, MC2Lab, Institut de Psychologie, F-92100 Boulogne-Billancourt, France
| | | | - Marion Doladilhe
- Sorbonne Université, Institut du Cerveau—Paris Brain Institute—ICM, Inserm, CNRS, Hôpital de la Pitié Salpêtrière, 75013, Paris, France
| | - Georg Dorfmüller
- Department of Pediatric Neurosurgery, Rothschild Foundation Hospital EpiCARE, 75019, Paris, France
| | - Homa Adle-Biassette
- Université de Paris Cité, service d’Anatomie Pathologique, APHP, Hôpital Lariboisière, DMU DREAM, UMR 1141, INSERM, 75010, Paris, France
| | | | - Stéphanie Baulac
- Correspondence to: Stéphanie Baulac Institut du Cerveau, 47 bd de l’hôpital, 75013, Paris, France E-mail:
| |
Collapse
|