Abstracts

Rationale: SPTAN1 encephalopathy is a rare genetic condition caused by abnormality in the production of spectrin proteins involved in stabilization of cell plasma membranes and intracellular organelles. Neurological features include epileptic encephalopathy with hypsarrhythmia, severe intellectual disability, motor impairment, poor visual attention, feeding difficulties, microcephaly, and spastic quadriplegia. Only one published study on the neurocognitive profile of a pediatric patient with de novo mutation of SPTAN1 was found and noted intact verbal reasoning skills, very low perceptual reasoning skills, and extremely slow processing speed in a 16-year-old male. We present data from two time points on a preteen female with de novo SPTAN1 mutation. Her presentation is unusual because she is not as severely impaired as is typically seen in this condition, making it possible for her to undergo comprehensive neuropsychological evaluation.

Methods: Patient is a right-handed female with focal, drug-resistant epilepsy, tethered spinal cord, hearing and vision problems, gastrointestinal complications, disrupted sleep, dysautonomia, arthromyalgia, and osteopenia associated with de novo SPTAN1 mutation. Her first seizure was at 15 months old followed by regression in speech/language skills. She also has non-epileptic events of staring, shivering, and stiffening. Video EEG studies indicated very frequent, moderate amplitude, sharp waves originating from the left > right occipital regions. Seizures have been well controlled more recently with lamotrigine. Brain MRI showed stable left hippocampal sclerosis. She underwent comprehensive neuropsychological evaluations at ages 7 and 9 years old.

Results: At both time points, patient’s scores ranged from well below to within age-expected range with relative strengths in verbal expressive skills and relative to significant weaknesses in attention, executive function, psychomotor speed, fine motor, visual motor integration, and social skills. Verbal learning and memory skills were underdeveloped for age but improved with recognition cues. Visual learning and immediate recall were below age expectation but improved following a longer delay. In contrast to a previously published study, reading decoding skills were a relative strength and math skills were well below age expectation. Evaluations resulted in diagnoses of attention deficit hyperactivity disorder that improved with stimulant treatment, and autism spectrum disorder.

Conclusions: De novo SPTAN1 mutations are rare and typically result in severe cognitive and physical impairments. Findings from two neuropsychological evaluations of a pediatric patient with a mild presentation of this condition revealed a cognitive performance marked by a high degree of variability. Verbal expressive skills were a relative strength while attention, executive function, psychomotor speed, fine motor, visual motor integration, and social skills were areas of relative to significant weakness across the two evaluations. This study is one of the first to provide information on the neurocognitive profile of de novo SPTAN1 mutation in a pediatric patient.

Funding: Please list any funding that was received in support of this abstract.: There was no funding received to support this abstract.