Award: ACG Outstanding Research Award in the Stomach and Spleen Category (Trainee)
Award: ACG Presidential Poster Award
Kara J. Jencks, MD, Nada Abdelnaem, MD, Irene Busciglio, BS, Paula Carlson, BS, Duane Burton, MHA, Michael Ryks, BS, Derek R. Johnson, MD, Patrick Navin, MBBCh, Corrie Bach, MD, Andrew M. Paulsen, PharmD, David J. Bartlett, MD, Michael Camilleri, MD, DSc Mayo Clinic, Rochester, MN Introduction: Gastric emptying (GE) scintigraphy, the gold standard for evaluating gastroparesis, utilizes a 99mTechnetium-labeled egg-based meal containing approximately 320 kcal and 30% fat, with a 4-hour imaging protocol developed and validated at Mayo Clinic with an intra-individual physiological variability (COVintra) for two replicate studies of 23.8%. However, its reliance on animal-derived ingredients presents a barrier for patients with egg allergies, lactose intolerance, and those adhering to vegan/plant-based, or other allergen-restricted diets. Our group recently validated a vegan and allergy-friendly alternative in vitro. This study aimed to evaluate a standardized, plant-based meal, free from egg, dairy, gluten, and nuts, that is calorically and nutritionally comparable to the standard egg meal. Methods: Ten healthy adult volunteers participated in a randomized, crossover design. Each underwent GE scintigraphy with both the standard egg and vegan JUST Egg® (primarily made of mung beans) meals, spaced 3–14 days apart. GE parameters, including gastric retention at 2 and 4 hours and gastric half emptying time (T1/2), were measured for the JUST Egg® meal and benchmarked against the standard chicken egg meal. The primary outcomes of interest were GE T1/2 and the percentage emptied at 4 hours. Secondary outcomes included the percentage emptied at 2 hours, lag time (defined as the time for 10% of the meal to empty from the stomach), and COVintra between the two test meals. Statistical analysis included Mann-Whitney rank sum testing and Blant-Altman analysis. Results: Gastric retention at 2 and 4 hours, as well as GE T1/2 demonstrated consistent agreement between the two meals. Observed differences were not statistically significant and remained consistently low across the different parameters: the mean difference in GE T1/2 was under 10 minutes, in GE at 4 hours was < 2%, and in GE at 2 hours was < 10%. The COVintra for GE T1/2 between egg and vegan meals was 18.8%. Discussion: The vegan JUST Egg® meal demonstrated in vivo GE performance comparable to the conventional chicken egg meal. The observed GE T1/2 COVintra was below the previously established 23.8% for the standard egg meal. Therefore, this vegan, allergy-friendly meal offers a valid and inclusive alternative for GE scintigraphy, supporting broader clinical implementation.
Figure: Figure 1. Compared gastric half emptying time (GE T1/2) for egg versus vegan meals. Left panel: Boxplot illustrating in vivo gastric half emptying time (GE T1/2) for the chicken egg and vegan JUST Egg® meals. Although the median GE T1/2 was slightly longer for the standard egg meal, the difference was not statistically significant (p = 0.307). Right panel: The Bland-Altman plot showed agreement between the two meals, with a mean difference of −9.82 minutes (95% CI: −24.64 to 4.99), indicating no significant statistical difference.
Figure: Figure 2. Compared gastric emptying at 4 hours for egg versus vegan meals. Left panel: Boxplot comparing gastric emptying percentages at 4 hours for the chicken egg and vegan JUST Egg® meals in vivo. The median values are nearly identical, with no statistically significant difference (p = 1.00). A single outlier in the vegan group shows approximately 20% lower emptying compared to the standard egg meal. Right panel: The Bland-Altman plot demonstrates close agreement between the two meals, with a minimal, non-significant mean difference of −1.94% (95% CI: −7.89 to 4.01).
Disclosures: Kara Jencks indicated no relevant financial relationships. Nada Abdelnaem indicated no relevant financial relationships. Irene Busciglio indicated no relevant financial relationships. Paula Carlson indicated no relevant financial relationships. Duane Burton indicated no relevant financial relationships. Michael Ryks indicated no relevant financial relationships. Derek R. Johnson: Cellectar – Consultant. Novartis – Consultant. Telix – Consultant. Patrick Navin indicated no relevant financial relationships. Corrie Bach indicated no relevant financial relationships. Andrew M. Paulsen indicated no relevant financial relationships. David J. Bartlett indicated no relevant financial relationships. Michael Camilleri: Alfasigma – Consultant. Amylyx – Consultant. Biocodex – Grant/Research Support. BioKier – Consultant. Brightseed Bio – Consultant, Grant/Research Support. Coloplast – Consultant. Dignify Therapeutics – Stock Options. Intercept – Consultant. Invea – Consultant. Kallyope – Consultant. McDermott Will & Emery – Consultant. Medpace – Consultant. Monteresearch – Consultant. Neurogastrx – Consultant. NGM Biopharmaceuticals – Grant/Research Support. Pfizer – Grant/Research Support. Phenomix – Stock Options. Renexxion – Consultant. SKYE Bioscience – Consultant. Sumitomo – Consultant. Synlogic – Consultant. Vanda – Grant/Research Support.
Kara J. Jencks, MD, Nada Abdelnaem, MD, Irene Busciglio, BS, Paula Carlson, BS, Duane Burton, MHA, Michael Ryks, BS, Derek R. Johnson, MD, Patrick Navin, MBBCh, Corrie Bach, MD, Andrew M. Paulsen, PharmD, David J. Bartlett, MD, Michael Camilleri, MD, DSc. P6310 - A Vegan and Allergy-Friendly Alternative for Gastric Emptying Scintigraphy: Validation in Healthy Participants, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.
