Epilepsy and EEG Phenotype of SLC13A5 Citrate Transporter Disorder

Qian-Zhou Yang, Emily M Spelbrink, Kimberly L Nye, Emily R Hsu, Brenda E Porter, Qian-Zhou Yang, Emily M Spelbrink, Kimberly L Nye, Emily R Hsu, Brenda E Porter

Abstract

Mutations in the SLC13A5 gene, a sodium citrate cotransporter, cause a rare autosomal recessive epilepsy (EIEE25) that begins during the neonatal period and is associated with motor and cognitive impairment. Patient's seizure burden, semiology, and electroencephalography (EEG) findings have not been well characterized. Data on 23 patients, 3 months to 29 years of age are reported. Seizures began during the neonatal period in 22 patients. Although seizures are quite severe in many patients later in life, seizure freedom was attainable in a minority of patients. Multiple patients' chronic seizure management included a few common medications, phenobarbital and valproic acid in particular. Patients EEGs had a relatively well-preserved background for age, even in the face of frequent seizures, little slowing and multiple normal EEGs and do not support an epileptic encephalopathy. Other causes for the motor and cognitive delay beyond epilepsy warrant further study.

Keywords: antiseizure drugs; developmental disability; epileptic encephalopathy; inborn errors of metabolism; neonatal seizures; seizures; status epilepticus.

Conflict of interest statement

Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

© The Author(s) 2020.

Figures

Figure 1.
Figure 1.
Seizure semiology. The number of patients reporting each seizure semiology.
Figure 2.
Figure 2.
Electroencephalography (EEG): Normal EEG background, awake, asleep, interictal EEG, hemiclonic seizure onset. A, Normal awake background at 7 years 6 months, patient 9. B, Normal sleep architecture at 4 years 2 months, patient 10. C, Multifocal spikes with otherwise normal background at 6 years 5 months, patient 8. D, Hemiclonic seizure with head turn to the left and left more than right body jerks, with brief right-sided lead to a more generalized high-voltage spike and wave, otherwise normal awake background at 11 year 2 months, patient 2.
Figure 3.
Figure 3.
Seizure frequency. Current seizure burden.
Figure 4.
Figure 4.
Current medication usage in all patients, including the seizure-free patient subset. The current number of patients using each medication is shown in blue. The medications of those patients who are seizure free or rare yearly seizures are shown in orange.
Figure 5.
Figure 5.
Electroencephalography (EEG): Neonatal EEG background and neonatal seizure. A, Normal background on day of life 8 in patient 1, with multifocal sharps. B, Seizure onset and excessive discontinuous background on day of life 3 in patient 12.

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Source: PubMed

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