Ultrasonographic Assessment of Liquid Gastric Emptying and Antral Motility According to the Subtypes of Irritable Bowel Syndrome in Children

Objectives: Gastric motor abnormalities have been reported in adults with irritable bowel syndrome (IBS), commonly in constipation-predominant IBS (IBS-C); however, such studies are uncommon in children. Furthermore, differences of gastric motility have not been studied in children with different IBS subtypes. Methods: Seventy-six children (33 [43%] boys, age 4-14 years, mean 7.9 years, SD 3.0 years) fulfilling Rome III criteria for IBS and 20 healthy controls (8 [40%] boys, age 4-14 years, mean 8.4 years, SD 3.0 years) were recruited (diarrhea-predominant IBS = 21, IBS-C = 31, mixed IBS = 19, and unsubtyped IBS = 5). Liquid gastric emptying rate (GER) and antral motility were assessed using an ultrasound method. Results: Average GER (43.8% vs 66.2% in controls), amplitude of antral contractions (56.4% vs 89%), and antral motility index (5.1 vs 8.3) were lower and fasting antral area (1.6 vs 0.6) was higher in patients with IBS (P < 0.0001). Frequency of antral contractions F (8.9 vs 9.3) did not show a significant difference. Patients exposed to stressful events had a significantly lower GER, compared to those not exposed to such events (P = 0.03). Gastric motility parameters had no correlation with severity of symptoms. GER (42.6%, 46.3%, 39.6%), fasting antral area (1.4 cm 2, 1.8 cm 2, 1.8 cm 2), amplitude of antral contractions (53%, 58.9%, 51.8%), frequency of antral contractions (8.7, 8.9, 9.2), and antral motility index (4.7, 5.3, 4.8) were not different among diarrhea-predominant IBS, IBS-C, and mixed IBS (P > 0.05). Conclusions: GER and antral motility parameters were significantly impaired in children with IBS compared with controls. GER and antral motility parameters were not different between IBS subtypes.