Subtypes of Irritable Bowel Syndrome in Children: Prevalence at Diagnosis and at Follow-Up (I.F.4,035)

Objectives: To assess the prevalence of irritable bowel syndrome (IBS) subtypes in childhood at diagnosis and their changes over 1 year. Study design: This is an observational, prospective, multicenter study. Consecutive pediatric patients with IBS, according to Rome III criteria, were enrolled over a 1-year period. Parents recorded weekly stool frequency and consistency and gastrointestinal and extraintestinal symptoms in a diary. Stool consistency was scored according to the Bristol Stool Form Scale. Children were evaluated after 2, 3, 6, and 12 months. Results: We enrolled 100 children with IBS (median age 9.9 years, range 4.2-16.7 years, 52 girls and 48 boys). At time of enrollment, constipation-IBS was the prevalent subtype (45%), with a prevalence of girls at 62% (P < .005); diarrhea-IBS was reported in 26% of children, with a prevalence of boys at 69% (P < .005); and alternating-IBS was described in 29% of children, without a difference between sexes. During the follow-up, 10% of patients changed their IBS subtypes at 2 months, 9% at 3 months, 7% at 6 months, and 6.3% at 12 months. Twenty-four percent of patients changed IBS subtype between the time of enrollment and 12 months. Conclusions: Constipation-IBS is the prevalent subtype in children, with a higher frequency in girls. In boys, diarrhea-IBS is the most common subtype. It is important to acquire knowledge about IBS subtypes to design clinical trials that may eventually shed new light on suptype-specific approaches to this condition