Below, we highlight findings from the consensus about the significance of early diagnosis, patterns of EEGs and MRIs and critical areas of counseling families should receive at diagnosis.
SCN8A Diagnosis
Discover the essential role of early diagnosis in SCN8A-related disorders with insights from Dr. Mitsuhiro Kato, an expert in pediatric neurology. This brief yet informative video presentation underscores the consensus on the vital importance of genetic testing for improving outcomes in SCN8A epilepsy. Learn about the significance of early and precise identification through genetic panels or whole exome sequencing, setting the stage for the comprehensive resources and guidelines available below.
Key Points:
- Early diagnosis of SCN8A is important to inform treatment and may improve long-term seizure outcomes.
- The function of an SCN8A variant (gain-of-function or loss-of-function) is important for informing treatment and anticipating phenotypes.
- Recognizing the wide range of clinical presentations is essential for accurate diagnosis and treatment planning.
Genetic Testing
Types of genetic testing recommended:
- Epilepsy gene panels
- Whole exome sequencing
- Whole genome sequencing can be insightful in cases of drug-resistant epilepsy or neurodevelopmental disorders without a clear cause.
Familial Testing
- All cases with new SCN8A variants should have parental testing conducted.
- Families newly diagnosed with SCN8A should receive genetic counseling.
EEGs & MRIs
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EEGsAlthough initial EEG may be normal, it typically becomes abnormal after epilepsy onset and remains so through the course of epilepsy.
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MRIsMRI results vary by phenotype for Severe DEE: Initial MRI is frequently normal But becomes abnormal over time (atrophy). For other phenotypes, initial MRI is frequently normal and most frequently remains normal.
Referrals???
There was moderate to strong consensus for each treatment item listed below. There are 4 treatment options that caregivers were not provided and therefore only clinician consensus is reported. There was 100% consensus on 3 items, SeL(F)IE first line treatments, sodium channel blockers for GOF variants in SCN8A, and seizure freedom among SCN8A LOF variants.
Legend:
The purple bar represents the consensus level among caregivers.
The orange bar represents the consensus level among clinicians.
Moderate Consensus: The first dashed line represents that at least 80% of respondents fully or partially agree, and fewer than 10% disagree.
Strong Consensus: The second dashed line represents when 80% or more of respondents fully agree.
Need for seizure emergency plan and rescue medications
Need for seizure emergency plan and rescue medications
Potential for drug-resistant epilepsy balancing seizure control and quality of life
Potential for drug-resistant epilepsy balancing seizure control and quality of life
Wide spectrum of severity
Wide spectrum of severity
Varying prognosis within and across phenotypes
Varying prognosis within and across phenotypes
Risk of sudden unexpected death in epilepsy (SUDEP)
Risk of sudden unexpected death in epilepsy (SUDEP)
Expected presence and evolution of comorbidities.
Expected presence and evolution of comorbidities.
Understanding seizure types and possible triggers.
Understanding seizure types and possible triggers.
Risks and benefits of recommended treatments
Risks and benefits of recommended treatments
Prognosis, as requested
Prognosis, as requested
Referrals/Suggested Counseling at Diagnosis
Types of genetic testing recommended:
- Epilepsy gene panels
- Whole exome sequencing
- Whole genome sequencing can be insightful in cases of drug-resistant epilepsy or neurodevelopmental disorders without a clear cause.
Familial Testing
- All cases with new SCN8A variants should have parental testing conducted.
- Families newly diagnosed with SCN8A should receive genetic counseling.
Learn More
- EEGs
Although initial EEG may be normal, it typically becomes abnormal after epilepsy onset and remains so through the course of epilepsy.
- MRIs
MRI results vary by phenotype for Severe DEE: Initial MRI is frequently normal But becomes abnormal over time (atrophy). For other phenotypes, initial MRI is frequently normal and most frequently remains normal.
– Keep Exploring –
IMPORTANT: While this consensus data provides new and valuable insights about best practices in the diagnosis and treatment of SCN8A, this is not medical advice. It can inform clinicians and caregivers alike in developing optimal treatment plans for each individual.
Disclaimer for Consensus and Individual Variation
This consensus process was carried out by a panel of expert clinicians who actively treat patients with SCN8A-related disorders. Guidelines determined from a consensus differ from those determined from a population-based study*. The extent of consensus reached is restricted by the number of patients seen by each clinician and the portion of the disease spectrum these patients represent.
Consensus guidelines serve as a recommended starting point for clinicians to treat patients based on the best evidence available. If an affected individual does not fit the expected profile, it is important to reassess your treatment plan and revise accordingly. Reassessment of the consensus guidelines will occur as new data become available and the number of patients seen by clinicians increases.
Guidelines based on future consensus processes will therefore reflect advancements in clinical care.
*Population-based studies reveal general trends for large subsets of the population. It is important to remember that each individual is unique and may not necessarily follow these trends regarding developmental progression, seizure remission, or effective treatment.