Characteristics of Developmental and Epileptic Encephalopathy Associated with PACS2 p.Glu209Lys Pathogenic Variant-Our Experience and Systematic Review of the Literature.

It is important to maintain a high suspicion of new pathogenic gene variants in adult patients presenting with a characteristic clinical picture correlated with radiologic changes. The neurologist must gradually recognize the distinct evolving phenotype of DEE66 in adult patients, and genetic testing must become a scenario with which the neurologist attending adult patients should be familiar. Accurate diagnosis is required for adequate treatment, genetic counseling, and an improved long-term prognosis.