In persons with an intellectual developmental disorder, obsessive-compulsive disorder (OCD) and autism spectrum disorder (ASD) are often difficult to differentiate, particularly when patients present major communication difficulties and low accessibility to subjective symptoms and clinicians are poorly trained in the specific psychopathological phenomenology. OCD and ASD share some important symptoms such as repetitiveness of behaviours, low flexibility to contextual variations or a narrow range of interests. The purpose of this study is to identify and describe symptomatological specificities, including how they manifest at behavioural level.
The present study is a retrospective case series study (n = 3) focusing on in-depth assessment, detection and comprehension of symptomatological specificities as well as on the direct observation of behavioural symptoms.
Some symptoms such as signs of sudden autonomous nervous system activation or behavioural equivalents of obsessive thoughts are crucial in achieving an effective differential or comorbidity diagnosis. These symptoms can be identified through a multidisciplinary and comprehensive evaluation, integrating present clinical and test findings with a thorough developmental and medical history. Symptoms should also be interpreted in the light of antecedent, contextual and personal factors.
Differential diagnosis between OCD and ASD in persons with major cognitive and communication issues is a rather neglected research area, although it has significant implications for treatment planning and implementation.
