The differential diagnosis of autism spectrum disorder in adults

Abstract

Introduction: Diagnosing autism spectrum disorder (ASD) in adults is challenging due to its heterogeneity and symptom overlap with other conditions. Making an accurate diagnosis can be difficult and overwhelming but is vital for proper accommodations and interventions while avoiding unproductive or harmful treatments.

Areas covered: The authors have based their review on a comprehensive literature search using PubMed, PsycINFO, and Google Scholar to identify relevant recommendations, diagnostic tools, and common differential diagnoses for adults with ASD. A clinical framework is provided based on the DSM-5 criteria, starting with an evaluation of childhood symptom onset and persistent manifestations of the core criteria - social and communication impairment, along with restricted, repetitive behaviors. Conditions with overlapping presentations, including personality disorders, anxiety, depression, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, and schizophrenia, are discussed, as well as challenges in differentiating these from ASD.

Expert opinion: Many factors complicate diagnosing ASD in adults - such as skewed public perception or misinformation spread on social media. Existing tools frequently miss subtle or atypical presentations, particularly in underdiagnosed groups like women and older adults. Promising advances in machine learning and artificial intelligence will hopefully improve diagnostic precision in the future. Up-to-date clinician training and large-scale research remain paramount for refining adult ASD diagnosis.

Keywords: Autism spectrum disorder; adults; developmental disorder; diagnostic criteria; differential diagnosis.