S0474 Identification of a New Entity of Abnormal Gastric Emptying and Implications for Therapy

Abstract

INTRODUCTION: A 4-hour Gastric Emptying Study (GES) is the gold standard diagnostic test for gastrointestinal motility disorders such as dumping syndrome (DS) and gastroparesis (GP). Classic DS is defined by rapid gastric emptying (GE) of >65% emptied gastric content at one hour. GP presents with delayed GE, in the absence of mechanical obstruction. Both entities have degrees of nausea, vomiting, abdominal pain and cramping, bloating, and diarrhea. We observed that some symptomatic patients with postprandial symptoms undergoing GES demonstrated rapid GE between 1 and 4 hours but were interpreted to have a normal GE based on established criteria. Our goals were to identify the frequency of this entity termed Delayed Onset Rapid Gastric Emptying (DRGE) in a large cohort of patients who underwent GES and their treatment outcomes. METHODS: GES cut-offs with hourly decrements were obtained previously from 24, female-dominated asymptomatic normal subjects. The upper threshold limits for GE decrement percentages were based on +1 standard deviation from the established mean. We reviewed the results of 4-hour GES in symptomatic patients from November 01, 2019, to March 31, 2020. The new GE thresholds were applied and analyzed in 98 patients who underwent GES during the period. RESULTS: The mean values of normal GE in controls were 36.6% ± 15.5 at 1–2 hr, 25.8% ± 11.4 at 2–3 hr, and 10.2% ± 8.8 at 3–4 hr. The upper threshold limit for GE decrement percentages were 52.1%, 37.2%, and 19.0%, at 1–2 hr, 2–3 hr, and 3–4 hr, respectively. After applying the cut-offs to the 98 GES reviewed over the five months, we identified that 7 (7.1%) of those symptomatic patients had hourly decrements that exceeded the established threshold. 6 were female, and 3 have diabetes mellitus. 1 patient (1.0 %) had exceeded the cut-off value for 1–2 hr, 4 patients (4.0%) for 2-3 hr and 2 (2.0%) on 3–4 hr, respectively. All had postprandial symptoms such as nausea, abdominal pain, bloating, and stool urgency beginning at least 1 hour after meal ingestion, subsequently responding to anticholinergic therapies. CONCLUSION: We have observed a new entity entitled DRGE in patients otherwise regarded as having a normal GE. DRGE is characterized by abnormal GE decrements from 1-4 hours after meal ingestion, accompanied by their presenting postprandial distress symptoms, which can be addressed by appropriate treatment. More data and studies are required to confirm the presence of this abnormal GE pattern in symptomatic patients.