Table 1.
Characteristics of patients with seizure associated demyelinating disorders.
| Demyelinating Disease | Epilepsy Prevalence | Clinical Manifestation | MRI Findings | Most Frequent Seizure Type | Electroencephalographic (EEG) Characteristics | Possible Pathophysiological Mechanism | Ref. | |
|---|---|---|---|---|---|---|---|---|
| Multiple sclerosis | 0.5–8.3% with an average of 2.3% |
Earlier onset of MS symptoms Worse cognitive performance in patients with frequent seizures or status epilepticus |
Cortical and juxtacortical lesions Extensive cortical inflammation lower brain volumes Temporal lobe damage: Hippocampus, lateral temporal lobe, cingulate, and insula Cortical thinning and alteration of diffusion metrics in temporal lobe including insular cortex and cingulate gyrus |
Partial secondary generalized | Diffuse asynchronous theta activity Synchronous rhythmic slow waves Focalized flattened EEG patterns Focal abnormalities |
Temporal lobe cortical pathology Inhibitory GABA interneuron cell loss in layers IV and VI Reduced cortical thickness in the middle temporal gyrus Type I GMLs mostly in middle temporal gyrus Decreased GABA in left hippocampus and posterior cingulate cortex of RRMS Presence of cortical lesions Progressive brain atrophy |
[25,26,27,28,42,43,44,45,46,47] | |
| Progressive multifocal leukoencephalopathy | 18% | New-onset seizures | Lesions adjacent to the hemispheric cortices |
Simple and complex partial seizures Partial seizures with secondary generalization |
- | - | [41] | |
| Antibody-associated demyelination | MOG-IgG * | 20.5% ** | Encephalopathy Younger onset age Higher EDSS score Meningeal irritation Fever, headache, nausea and vomiting CSF leukocytosis |
Inflammatory cortical brain lesions Subcortical white matter lesions Deep white matter lesion including periventricular and corpus callosum Cerebral peduncle less optic nerve and spinal cord involvement |
Generalized tonic clonic seizure | Background theta to delta rhythm Intermittent low amplitude fast waves Focal sharp-wave Complex and asymmetric focal slow waves |
- | [33,40,48,49] |
| AQP4-IgG *** | 1% | - | - | - | - | Slow K+ clearance | [33,50] | |
GABA: Gamma-Aminobutyric Acid; GMLs: Gray matter lesions; EDSS: Expanded Disability Status Scale; CSF: Cerebrospinal fluid; RRMS: relapsing-remitting MS. * MOG-Abs associated demyelination is related to several demyelinated disorders such as acute disseminated encephalomyelitis (ADEM), pediatric MS, transverse myelitis, optic neuritis (ON), and AQP4-Abs negative neuromyelitis optica spectrum disorders (NMOSD). ** A recent meta-analysis of 14 studies reported that general probability of seizure occurrence in patients with MOG-Ab-associated disease is 20.5%, particularly in children. Furthermore, the occurrence of seizure in patients with ADEM-like phenotype of MOG-Ab-associated disease is 37.3% [49]. *** Antibodies against AQP4 is a criterion for NMOSD diagnosis.