Crossed Cerebellar Diaschisis in EEG Negative Epilepsia Partialis Continua

Case

A 15-year-old girl, with right centroparietal focal epilepsy, presented with new onset continuous, multifocal, jerking movements of her right-sided limbs and neck (contralateral to her known epileptic focus), without electroencephalography (EEG) correlate initially. The movements were medically intractable. Magnetic resonance imaging (MRI) showed T2/fluid-attenuated inversion recovery (FLAIR) hyperintensities and restricted diffusion in the left precentral gyrus, left thalamus, and right superior cerebellum ([Fig. 1]). Whole exome sequencing revealed she was homozygous for a pathogenic variant in the POLG gene (c.1399G > A; p.A467T). POLG mutations are the most common cause of inherited mitochondrial disorders.[1] Later in the course of the admission, clear epileptiform discharges were seen arising from the left hemisphere. Seizures, including epilepsia partialis continua (EPC), are the initial clinical manifestation in 50% of cases.[1] Crossed cerebellar diaschisis (CCD), as seen in this patient with EPC, was likely a result of excessive and prolonged excitatory synaptic activity via a corticothalamic-cerebellar pathway.[2] [3] CCD has rarely been described in children, but has been previously described in children with stroke, seizures, Rasmussen's encephalitis, and hemiplegic migraine.[4] This case highlights that EEG can be unrevealing in some cases of EPC.

Fig. 1 Diffusion-weighted imaging (DWI) (A, C, E) and fluid-attenuated inversion recovery (FLAIR) sequences (B, D, F) showing restricted diffusion with corresponding T2/FLAIR hyperintensities in the left precentral gyrus (A, B), left thalamus (C, D), and right superior cerebellum (E, F).

Ethical Approval

The authors confirm that ethical standards have been maintained in accordance with the Declaration of Helsinki and the standards of the journal.

Author Contributions

T.L.: design and conceptualization of manuscript, drafting and revision of manuscript. S.P.: drafting and revision of manuscript.

Publikationsverlauf

Eingereicht: 11. Februar 2021

Angenommen: 26. August 2021

Artikel online veröffentlicht:
21. Oktober 2021

• References

• 1 Rahman S, Copeland WC. POLG-related disorders and their neurological manifestations. Nat Rev Neurol 2019; 15 (01) 40-52
• 2 Graffeo CS, Snyder KA, Nasr DM, Murphy ME, Carr CM, Hocker SE. Prognostic and mechanistic factors characterizing seizure-associated crossed cerebellar diaschisis. Neurocrit Care 2016; 24 (02) 258-263
• 3 Bailly P, Bazire A, Prat G, Ben Salem D. Crossed Cerebellar Diaschisis in Status Epilepticus. Vol. 46. Paris, France: Presse Medicale; 2017
• 4 Poretti A, Boltshauser E. Crossed cerebro-cerebellar diaschisis. Neuropediatrics 2012; 43 (02) 53-54