Gastric emptying and antral motility according to the subtypes of irritable bowel syndrome: a paediatric study

Abstract

BACKGROUND: Irritable bowel syndrome (IBS) is a common paediatric functional gastrointestinal disorder. It is subtyped into diarrhoea predominant (IBS-D), constipation predominant (IBS-C), mixed (IBS-M) and untypable (IBS-U) IBS depending on stool consistency. Several studies have reported differences in colonic motility in children with different IBS subtypes. However, gastric motility has not been assessed according to subtypes yet. AIM: To assess gastric motility in children with different IBS subtypes using a non-invasive ultrasound method. METHODS: Seventy six children with IBS [33 (43%) males, age 4–14 years, mean 7.9 years, SD 3.0 years) referred to the Gastroenterology Research Laboratory, Faculty of Medicine, University of Kelaniya, Sri Lanka, for gastric motility studies and 20 healthy controls [8 (40%) males, age 4–14 years, mean 8.4 years, SD 3.0 years] were recruited. Children with IBS were divided into IBS-D(n=21), IBS-C(n=31), IBS-M (n=19) and IBS-U (n=5) according to Rome III definitions. None of the patients recruited had clinical or laboratory evidence of organic disorders. Liquid gastric emptying rate (GER) and antral motility parameters were assessed using a previously reported ultrasound method. RESULTS: Compared to healthy controls, the mean GER (43.8% vs. 66.2% in controls), amplitude of antral contractions (A) (56.4% vs. 89%) and antral motility index (MI) (5.1 vs. 8.3) were significantly lower and fasting antral area (FA) (1.6 vs. 0.6) was higher in children with IBS ( p<0.0001). Frequency of antral contractions (F) (8.9 vs. 9.3) did not show a significant difference between the two groups. Patients exposed to recent stressful life events had a significantly lower mean GER (40.3%), compared to those who were not (45.7%) ( p=0.03). No significant relationship was observed between severity of symptoms and motility abnormalities. No significant differences were found between IBS-D, IBS-C and IBS-M with respect to GER (42.%, 46.3%, 39.6%), FA (1.4 cm2,1.8 cm2, 1.8 cm2), A (53%, 58.9%, 51.8%), F (8.7, 8.9, 9.2) and MI (4.7, 5.3, 4.8). CONCLUSIONS: GER and antral motility parameters were significantly impaired in children with IBS compared to controls. No significant difference observed in gastric motility parameters between different IBS subtypes. GER was lower in those exposed to recent stressful events