Severe Developmental Delay and Behavior Abnormalities in a Patient with De Novo CAMK2B Mutation: A Case Report and Literature Review.

The calcium/calmodulin-dependent protein kinase II-beta ( CAMK2B ) gene is important for calcium signaling and glutamatergic synapses, which impacts neuroplasticity and learning. Mutations in the CAMK2B gene, which cause autosomal dominant mental retardation 54 (Online Mendelian Inheritance in Man # 617799), can have multisystemic clinical impact. Due to the rarity of CAMK2B mutations at present, case reports about patients with CAMK2B mutations are limited. The present case report describes a patient with CAMK2B -related disorder confirmed by whole exome sequencing and adds to the current information in the literature. We review three case reports in literature with detailed descriptions of patients presenting with mutations in the CAMK2B gene. While there is a broad spectrum of phenotypic presentations, there appears to be an emerging neurobehavioral phenotype. Optimal management of patients will require attention to behavioral issues as well as involvement of neuropsychiatric expertise along with other supports for development and vision abnormalities.