Gastrointestinal manifestations and their relation to faecal calprotectin in children with autism

Introduction
A common comorbidity in autism spectrum disorder (ASD) children is gastrointestinal problems, and a possible link between active gastrointestinal inflammation and autism has been suggested. Faecal calprotectin (FC) is a non-invasive marker for of gastrointestinal inflammation.

Aim: To study the level of FC as a marker of bowel inflammation in children with ASD and its possible relation to gastrointestinal manifestations.

Material and methods
Calprotectin levels were assessed in stool samples of 40 ASD children. Autism severity was assessed by the Childhood Autism Rating Scale (CARS). Severity of gastrointestinal symptoms was assessed using a modified version of the 6-Item Gastrointestinal Severity Index (6-GSI) questionnaire. A control group of 40 healthy children matched for age and sex with the cases was also included to compare their levels of FC.

Results
Gastrointestinal symptoms were present in 82.5% of children with autism; the most reported offensive stool odour (70%) and the least diarrhoea (17.5%), and a high 6-GSI score was observed in 35% of ASD children. FC levels were elevated in 35% of the cases and in 25% of the control group. The mean levels of FC of cases were significantly elevated compared to levels of controls. FC levels positively correlated with severity of gastrointestinal symptoms (6-GSI) in autistic patients. There was positive correlation between CARS and 6-GSI.

Conclusions
Gastrointestinal manifestations are a common comorbidity in autistic patients. ASD patients have significantly higher FC levels than healthy controls. FC levels are strongly correlated with the severity of gastrointestinal manifestations in ASD children. So, gastrointestinal manifestations among autistic patients could be caused by gastrointestinal inflammation.