Behavioral and Psychiatric Phenotypes in 22q11.2 Deletion Syndrome.

22q11.2 Deletion syndrome (22q11.2DS) is a chromosomal microdeletion that affects approximately 40 to 50 genes and affects various organs and systems throughout the body. Detection is typically achieved by fluorescence in situ hybridization after diagnosis of one of the major features of the deletion or via chromosomal microarray or noninvasive prenatal testing. The physical phenotype can include congenital heart defects, palatal and pharyngeal anomalies, hypocalcemia/hypoparathyroidism, skeletal abnormalities, and cranial/brain anomalies, although prevalence rates of all these features are variable. Cognitive function is impaired to some degree in most individuals, with prevalence rates of greater than 90% for motor/speech delays and learning disabilities. Attention, executive function, working memory, visual-spatial abilities, motor skills, and social cognition/social skills are affected. The deletion is also associated with an increased risk for behavioral disorders and psychiatric illness. The early onset of psychiatric symptoms common to 22q11.2DS disrupts the development and quality of life of individuals with the syndrome and is also a potential risk factor for later development of a psychotic disorder. This review discusses prevalence, phenotypic features, and management of psychiatric disorders commonly diagnosed in children and adolescents with 22q11.2DS, including autism spectrum disorders, attention deficit/hyperactivity disorder, anxiety disorders, mood disorders, and schizophrenia/psychotic disorders. Guidelines for the clinical assessment and management of psychiatric disorders in youth with this syndrome are provided, as are treatment guidelines for the use of psychiatric medications.