Background. Gastrointestinal system disorders are known to be prevalent among children with autism spectrum disorder (ASD). Some ASD-associated comorbidities are abdominal pain, constipation, diarrhea, gastroesophageal reflux, sleep disturbances, epilepsy, and psychiatric problems. Nonetheless, there is still limited information about the presence of functional GI disorders (FGIDs) among children with ASD, especially in Türkiye. Using the Rome criteria, we aimed to investigate FGIDs in children with ASD.

Methods. The sample of the study consisted of 68 children aged 4-10 years, diagnosed with ASD according to the DSM-5 diagnostic criteria and had scores greater than 30 on the Childhood Autism Rating Scale (CARS-2) and an age-sex matched control group (n=78). The Rome III criteria were used to evaluate FGIDs.

Results. The frequency of FGIDs in the ASD group was higher (76.5%) compared to the control group (p<0.001). Compared to the control group, abdominal migraine frequency increased 10 times (p=0.012), functional constipation 7 times (p<0.001), and fecal incontinence 6 times (p<0.001) in the ASD group. Stool retention was not present in most children in the ASD group who were found to have fecal incontinence.

Conclusion. In this study, the most common FGIDs in the ASD group were abdominal migraine, functional constipation, and non-retentive fecal incontinence. The finding that most children with ASD who had fecal incontinence did not show stool retention implicated social, psychological, and behavioral factors as the causes of incontinence. Raising awareness of healthcare professionals about the frequency of FGIDs in children with ASD will improve many areas in the daily lives of these children.

Keywords: autism spectrum disorder, functional gastrointestinal disorders, constipation, abdominal migraine, fecal incontinence, stool retention