Infantile epileptic spasm syndrome as a new NR2F1 gene phenotype

IntroductionNR2F1 pathogenetic variants are associated with the Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS). Recent studies indicate that BBSOAS patients not only have visual impairments but may also have developmental delays, hypotonia, thin corpus callosum and epileptic seizures. However, reports of BBSOAS occurrence along with infantile epileptic spasm syndrome (IESS) are rare.MethodsHere, we report three cases involving children with IESS and BBSOAS caused by de novo NR2F1 pathogenetic variants and summarize the genotype, clinical characteristics, diagnosis and treatment of them.ResultsAll three children experienced epileptic spasms and global developmental delays, with brain Magnetic Resonance Imaging (MRI) suggesting abnormalities (thinning of the corpus callosum or widened extracerebral spaces) and two of the children exhibiting abnormal visual evoked potentials.ConclusionsOur findings indicate that new missense NR2F1 pathogenetic variants may lead to IESS with abnormal visual evoked potentials. Thus, clinicians should be aware of the Bosch-Boonstra-Schaaf optic atrophy syndrome and regular monitoring of the fundus, and the optic nerve is necessary during follow-up. (a) Brain MRI examination of Case 1 shows thinning of the corpus callosum. (b) EEG examination during the seizure period in Case 1 shows high-amplitude disorganization. (c) Brain MRI examination of Case 2 shows widened extracerebral spaces. (d) EEG examination during the seizure period in Case 2 shows high-amplitude disorganization. (e) Brain MRI examination of Case 3 shows widened extracerebral spaces. (f) EEG examination during the seizure period in Case 3 shows high-amplitude disorganization.image