Comorbid Autism Spectrum Disorder and Attention-Deficit/Hyperactivity Disorder in a Patient with 6q25.1–Q25.3 Microdeletion: A Case Report

6q25 microdeletion is a rare syndrome associated with intellectual disability and dysmorphism. However, comorbid Autism Spectrum Disorder (ASD) and Attention Deficit and Hyperactivity Disorder (ADHD) are poorly documented. We report a 16-year-old male with a 6.7 Mb deletion (6q25.1-q25.3) presenting with hydrocephalus, cerebral palsy, and severe behavioral dysregulation. Psychiatric evaluation confirmed comorbid ASD (CARS: 52) and ADHD. Behavioral symptoms and aggression were successfully stabilized using 5 mg/day olanzapine. Our case is the first report of ASD/ADHD co-occurrence in 6q25 syndrome highlights the potential neurobehavioral role of genes like ARID1B and SYNE1. Our findings emphasize the need for comprehensive psychiatric evaluation in rare chromosomal aberrations.