A Phenomenological Approach to Diagnosing Psychosis in Autism Spectrum Disorder and Intellectual Disability: A Case Series

Purpose: The diagnosis of psychosis in individuals with autism spectrum disorder poses a

unique clinical challenge. The presence of intellectual disability further complicates the

diagnostic picture. Reliable and timely diagnosis of psychosis in such individuals minimizes

the duration of untreated psychotic symptoms and the subsequent impact on the quality of life

of the patients concerned.

Design/methodology/approach: The authors present four patients with psychosis, autism

spectrum disorder and intellectual disability, who have received care within forensic mental

health and intellectual disability settings. These examples demonstrate the interaction

between these conditions, as well as issues pertaining to diagnosis and management.

Findings: In all four patients, sustained use of antipsychotic medication was objectively

associated with an improvement in psychotic symptoms and quality of life. In instances

where autistic phenomena were accentuated upon development of psychosis, such features

returned to the baseline levels evident prior to the onset of psychosis.

Practical implications: The discussion and related case examples could improve

understanding of the possibility of psychosis in individuals with autism spectrum disorder

and intellectual disability, and increase awareness of this diagnostic possibility among

healthcare professionals.

Originality/value: This is the first published case series illustrating the challenges of

diagnosing psychosis in individuals with autism spectrum disorder and intellectual disability.