Research into gastrointestinal (GI) symptoms and disorders in autism spectrum disorder (ASD) is a relatively new area of study. This may be because gastrointestinal symptoms can be very difficult to diagnose in individuals with ASD. Diagnosis can be especially difficult for individuals who are non-verbal or who have severe deficits in communicating their needs and wants. If an individual is in pain and cannot communicate this to caregivers, it makes it very difficult to recognize potential gastrointestinal symptoms. Gastrointestinal symptoms in individuals with ASD may present themselves differently than in typically developing individuals. A person with ASD may not reach for their abdomen if in pain. Instead, they may display this pain through challenging behavior.
All too often, comorbid conditions such as gastrointestinal symptoms are seen as being part of ASD, instead of being recognised as a separate comorbid condition. It is very important that we study and understand gastrointestinal symptoms in ASD, as they may be potentially exacerbating symptoms of ASD such as repetitive behavior. Gastrointestinal symptoms have the potential to jeopardize interventions designed to reduce challenging behavior in children and adults with ASD, and interventions designed to teach new skills such as communication skills, academic skills and self-help skills. An individual with ASD who has what appears to be difficulties with toileting or feeding may also have comorbid gastrointestinal symptoms. If intervention just focuses on the presenting issue such as challenging behavior or toilet training, practitioners may find that there are difficulties with teaching certain skills. These difficulties may be due to an individual with ASD experiencing pain and discomfort. It is imperative that we look at the environment for the individual with ASD, but that we also examine the whole body, including gastrointestinal symptoms and disorders.