English

Epilepsy Of Infancy With Migrating Focal Seizures

Etiologies: Unknown, some are related to gene mutations (such as KCNT1 (the most common), SLC25A22, PLCB1, SCN1A, SCN2A, SCN8A, GABRG2, TBC1D24, GABRB3, CLCN2, PCDH19, PRRT2, ATP7A, FGF12, FGF13, QARS, SLC12A5, ALDH7A1, DOCK6, ALG1, WWOX etc.) [1-14].

Age of onset: typically has onset in the first six months of life (mean 3 months).

Seizure characteristics: It can show focal motor seizures (which can occur alone or in combination with promient autonomic features at the same time, and can be sporadic at first, but then typically show a rapid increase in frequency in the weeks to months after seizure onset. Focal clonic seizures are common (involving arms or eyelids), and behaviour arrest can occur (with or without head and eye version)), it can often progress to generalized tonic clonic seizures, and both sides can be involved alternately. In the same single seizure or status epilepticus event , random but continuous migratory focal seizures involving multiple independent cortical regions is a mandatory criteria for this syndrome [15-16].

EEG: In the early stage of onset, the interictal EEG can be normal. With the progress of the disease, the background slows down, and multifocal slow wave and spike wave appear. During the ictal, EEG showed multifocal origin (typically rhythmic alpha or theta activities), often swimming from one hemisphere to the other, or swimming in the same hemisphere, sometimes only subclinical ictal discharges [16-17].

Brain MRI: Some of them were normal in the early stage and showed nonspecific changes such as atrophy in the later stage.

Developmental progress: Some may be normal in the early stage, but often develop into severe developmental backwardness in the later stage.

 

Reference

  1. Barcia, G., et al., De novo gain-of-function KCNT1 channel mutations cause malignant migrating partial seizures of infancy.Nat Genet, 2012. 44(11): p. 1255-9.
  2. Poduri, A., et al., SLC25A22 is a novel gene for migrating partial seizures in infancy. Ann Neurol, 2013. 74(6): p. 873-82.
  3. Poduri, A., et al., Homozygous PLCB1 deletion associated with malignant migrating partial seizures in infancy.Epilepsia, 2012. 53(8): p. e146-50.
  4. Carranza Rojo, D., et al., De novo SCN1A mutations in migrating partial seizures of infancy.Neurology, 2011. 77(4): p. 380-3.
  5. Howell, K.B., et al., SCN2A encephalopathy: A major cause of epilepsy of infancy with migrating focal seizures.Neurology, 2015. 85(11): p. 958-66.
  6. Early onset epileptic encephalopathy caused by de novo SCN8A mutations. Epilepsia, 2014. 55(7): p. 994-1000.
  7. Novel variants and phenotypes widen the phenotypic spectrum of GABRG2-related disorders. Seizure, 2019. 69: p. 99-104.
  8. Milh, M., et al., Novel compound heterozygous mutations in TBC1D24 cause familial malignant migrating partial seizures of infancy.Hum Mutat, 2013. 34(6): p. 869-72.
  9. Sterbova, K., et al., Neonatal Onset of Epilepsy of Infancy with Migrating Focal Seizures Associated with a Novel GABRB3 Variant in Monozygotic Twins. Neuropediatrics, 2018. 49(3): p. 204-208.
  10. Takeguchi, R., et al., Two Japanese cases of epileptic encephalopathy associated with an FGF12 mutation.Brain Dev, 2018. 40(8): p. 728-732.
  11. Coppola, G., et al., Mutational scanning of potassium, sodium and chloride ion channels in malignant migrating partial seizures in infancy. Brain Dev, 2006. 28(2): p. 76-9.
  12. McTague, A., et al., The genetic landscape of the epileptic encephalopathies of infancy and childhood. Lancet Neurol, 2016. 15(3): p. 304-16.
  13. McTague, A. and M.A. Kurian, SLC12A5-Related Epilepsy of Infancy with Migrating Focal Seizures, in GeneReviews((R)), M.P. Adam, et al., Editors. 1993: Seattle (WA).
  14. Liwen Wu., et al., Epilepsy of Infancy With Migrating Focal Seizures (EIMFS): Expansion of Clinical Phenotypic And Genotypic Spectra. Scientific Reports, 2021.12 (under review, for medical professional reference only).
  15. International League Against Epilepsy. Epilepsy of infancy with migrating focal seizures (Accessed December 27, 2021).
  16. Panayiotopoulos.  癫痫综合征及临床治疗.  北京 : 人民卫生出版社, 2012.
  17. 刘晓燕.  临床脑电图学. 第2版.  北京 : 人民卫生出版社, 2017.