TOP2B and infantile spasms: Herein, we describe an additional case of a child who presented with “infantile epileptic spasms syndrome” (IESS) as the first symptom, B-cell immunodeficiency, dysmorphic facial features, and a pathogenic variant in TOP2B. The c.1901A > G variant in TOP2B is new to our study, which further enriches the genotype of TOP2B deficiency.