The 22q11.2 deletion syndrome (22q11DS) is a neurogenetic condition characterized by high rates of psychiatric disorders. To our knowledge, this is the first study to assess psychiatric disorders in young children with 22q11DS using a structured psychiatric diagnostic interview, and one of few studies to use the complete gold standard diagnostic evaluation to examine the prevalence of autism spectrum disorder (ASD) in young children with 22q11DS and compare it to a matched control group with iASD.

We identified the psychiatric disorders and autistic phenotype of young children with 22q11DS (age 3–8 years) and compared them with those of age and sex-matched children with idiopathic autism (iASD). We used the gold standard psychiatric and ASD assessments including the Autism Diagnostic Interview-Revised (ADI-R), the Autism Diagnostic Observation Schedule (ADOS) and a clinical examination by a child psychiatrist.

Eighty-four percent of the children with 22q11DS had at least one psychiatric disorder, including anxiety disorders and ADHD, and 16% met strict criteria for ASD. Children with 22q11DS and ASD symptoms had less severe overall ASD symptoms than those with iASD. Children with 22q11DS, regardless of ASD diagnosis, were characterized by repetitive restricted behaviors.

Our results highlight the need to screen for psychiatric disorders in 22q11DS and treat them already in preschool years.