Targeted Food Elimination for Treatment of Functional Gastrointestinal Diseases in Children

Recurrent Abdominal Pain (RAP) in children is common and causes significant functional impairment and poor quality of life. Lifestyle factors such as diet, anxiety, and stress are important triggers of abdominal pains, but there is lack of high quality research evidence on optimal treatment modalities in children. This study aims to evaluate the effect of food elimination on abdominal pain frequency and severity in a cohort of children with abdominal pain associated Functional Gastrointestinal Diseases (FGID). The primary outcome will be a comparison of abdominal pain frequency and severity between standard therapy and targeted food elimination, based on IgG antibody results to a multiple food antigen panel. The investigators anticipate that 'targeted dietary elimination' as a treatment strategy will resolve abdominal pain and improve quality of life in children.

Randomized controlled single center trial. Setting: Outpatient pediatric gastroenterology (PG) clinic, Children's Hospital, London, Canada. Methodology: After a 4 week run in period, 60 children aged 5-18 years, meeting Rome 3 inclusion criteria for abdominal pain associated FGID will be recruited to the trial. After informed consent, the participants will be randomized to either a standard treatment or lifestyle modification (dietary elimination) group in the ratio of 1:1. IgG testing to food antigens will be completed in both groups using a commercially available specific IgG ELISA-based multiple food allergen panel but will ONLY be disclosed for the lifestyle modification group. The patient will receive specific advice by a dietitian to exclude a maximum of two food items from his/her diet for 4 weeks. Children will be followed-up in PG clinic at 4-weekly intervals for 16 weeks. At every clinic visit, Diary of food intake, Abdominal Pain Index (API) and Quality of Life (QOL) questionnaire will be completed by both child and parent. The standard therapy group will receive conventional treatment for Abdominal Pain (AP) as per usual practice at the PG Clinic. Response is defined as more than 50% improvement in frequency and severity of abdominal pain. At each follow up visit, non-responders will cross over to the other arm of the study. At the end of the trial, non-responders in either group will continue to receive conventional treatment in the PG Clinic. Responders will be discharged back to their family physicians. Data will be analyzed using IBM SPSS Statistics, version 22.0.

Eligibility Criteria:
Inclusion Criteria:

1. Children 5-18 years of age with a diagnosis of Abdominal Pain-related FGIDs (Functional Abdominal Pain , FAP syndrome, Functional Dyspepsia, Irritable Bowel Syndrome, Abdominal Migraine) as defined by the Rome 3 criteria.
2. Acquisition of informed consent

Exclusion Criteria:

1. Children less than 5 years of age
2. Organic cause of abdominal pain established by investigations (e.g. Crohn's disease)
3. Diagnosis of failure-to-thrive or co-morbid chronic physical disease (e.g., Diabetes)
4. Any medical condition that in the opinion of the investigator would be unsafe for trial participation.
5. Lack of follow-up or failure to comply with study procedures.