Executive Function in Nephropathic Cystinosis

Abstract

We studied executive function (EF) in children and adolescents with cystinosis. Cystinosis is a genetic metabolic disorder in which the amino acid cystine accumulates in all organs of the body, including the brain. Previous research has shown that individuals with cystinosis have visuospatial deficits, but normal intelligence and intact verbal abilities. Better understanding of the behavioral phenotype associated with cystinosis could have important implications for treatment. Twenty-eight children with cystinosis and 24 control participants (age range 8 to 17 years) underwent selected Delis-Kaplan executive function system tests for neuropsychological assessment of EF, and the participants' parents completed the behavior rating inventory of executive function. Participants with cystinosis performed significantly more poorly than controls on all Delis-Kaplan Executive Function System indices examined and on the behavior rating inventory of executive function metacognition index and global executive composite. EF is an area of potential risk in cystinosis. Our data have implications not only for the function of affected children and adolescents in school and daily life, but also for disease management and treatment adherence. Our findings can aid in the design and implementation of interventions and lead to a greater understanding of brain-behavior relationships in cystinosis.