C0279 - Prevalence of Disaccharidase Deficiencies in Adults With Irritable Bowel Syndrome and Functional Diarrhea: Interim Analysis From a Multicenter, Prospective U.S. Trial

Monday, October 24, 2022

3:00 PM – 5:00 PM ET

Location: Crown Ballroom

Has Audio

Presenting Author(s)

Samuel W. Chey, MPH

University of Michigan Health System
Ann Arbor, MI

Samuel W. Chey, MPH¹, William D. Chey, MD², Brooks D. Cash, MD, FACG³, Shanti L. Eswaran, MD, FACG¹
¹University of Michigan Health System, Ann Arbor, MI; ²Michigan Medicine, Ann Arbor, MI; ³University of Texas Health Science Center, Houston, TX

Introduction: Disaccharidases are brush border enzymes that digest disaccharides to monosaccharides for absorption across the intestinal epithelium. Patients with disaccharidase deficiencies (DD) may experience post-prandial abdominal pain, bloating, flatulence, & diarrhea that can mimic Irritable Bowel Syndrome and diarrhea (IBS-D) & functional diarrhea (FD). While well-characterized in children, the prevalence of DDs in symptomatic adults is poorly defined.

Methods: In this ongoing study, adult ( >18 yrs) patients fulfilling Rome IV diagnostic criteria for IBS-D or FD were recruited at Michigan Medicine (UM) & the University of Texas Health Science Center at Houston (UTH). Exclusion criteria included pregnancy, lactation, severe GI or abdominal co-morbidities, & history of previous GI surgeries excluding cholecystectomy or appendectomy. Eligible patients completed upper endoscopy (EGD) with 2-4 small intestinal biopsies collected from the duodenum distal to the ampulla of Vater. Biopsy samples underwent disaccharidase assay to measure disaccharidase activity (normal sucrase: >28.0 µM/min/g, maltase: >120.8 µM/min/g, lactase: >15.4 µM/min/g, palatinase: >9.8 µM/min/g, glucoamylase: >13.1 µM/min/g) using validated protocols at experienced reference labs (Arnold Palmer Hospital Labs & Joli Diagnostics, Inc.).

Results: 154 patients (mean age = 45.6 yrs, 47% IBS-D, 53% FD, 74% female, 87% white) were enrolled & underwent EGD with biopsies collected to test for DD. More than a third of patients (56/154, 36.4%) had >1 DD. The most common DD was for lactase, found in 54 (35.1%) patients. Eleven patients (7.1%) tested positive for Sucrase-Isomaltase deficiency. Glucoamylase & palatinase deficiencies were each identified at 5%. Only lactase deficiency occurred in isolation. All patients with non-lactase deficiencies had other DDs, with at least 27% of these patients having pan-DDs (Table 1). The prevalence of the DDs were almost identical at both sites (Figure 1).

Discussion: More than 36% of US adult patients with IBS-D or FD had >1 DD. Lactase deficiency was the most common DD & the most likely to occur in isolation. Sucrase & maltase deficiencies were identified in approximately 1 in 14 symptomatic patients, & typically associated with at least 1 other DD. Lactase & non-lactase DD may be important & overlooked causes for symptoms in US patients with IBS-D or FD.

Figure: Figure 1. Disaccharidase deficiency prevalence rates by study site. **Glucoamylase was not measured for patients recruited by and screened at UTH.

A	Total	< 1 Def	1 Def	2 Def	3 Def	4 Def	5 Def
Total	154	63.64%	27.27%	2.60%	1.95%	2.60%	1.95%
Sucrase	11	0%	0%	9.09%	27.27%	36.36%	27.27%
Maltase	11	0%	0%	18.18%	27.27%	27.27%	27.27%
Lactase	54	0%	77.78%	5.56%	3.70%	7.41%	5.56%
Palatinase	8	0%	0%	12.50%	12.50%	37.50%	37.50%
Glucoamlyase	6	0%	0%	16.67%	0%	33.33%	50.00%
B	Sucrase	Maltase	Lactase	Palatinase	Glucoamylase
Total	11	11	54	8	6
Sucrase	X	90.91%	16.67%	87.50%	83.33%
Maltase	90.91%	X	16.67%	75.00%	66.67%
Lactase	81.82%	81.82%	X	87.50%	100.00%
Palatinase	63.64%	54.55%	12.96%	X	66.67%
Glucoamylase	62.50%	57.14%	15.00%	66.67%	X

Table: Table 1. Characterization of Disaccharidase Deficiencies
(A, Top) Prevalence of single or multi-enzymatic deficiencies by disaccharidase
(B, Bottom) Prevalence of enzymatic deficiency overlap by disaccharidase

Disclosures:

Samuel Chey indicated no relevant financial relationships.

William Chey: Abbvie – Consultant. Allakos – Consultant. Alnylam – Consultant. Arena – Consultant. Biomerica – Consultant. Commonwealth Diagnostics International – Consultant. Gemelli – Consultant. GI OnDEMAND – Stock Options. Ironwood – Consultant. Isothrive – Consultant. Isothrive – Stock Options. Modify Health – Stock Options. Nestle – Consultant. Phathom – Consultant. Progenity – Consultant. QOL Medical – Consultant, Grant/Research Support. Redhill – Consultant. Salix – Consultant, Grant/Research Support. Urovant – Consultant. Vibrant – Consultant.

Brooks Cash: AbbVie – Consultant, Speakers Bureau. Ardelyx – Consultant, Speakers Bureau. Motus – Consultant. QOL – Consultant, Speakers Bureau. RedHill – Consultant, Speakers Bureau. Salix – Consultant, Speakers Bureau. Takeda Pharmaceuticals – Consultant.

Shanti Eswaran: QOL Medical – Grant/Research Support.

Samuel W. Chey, MPH¹, William D. Chey, MD², Brooks D. Cash, MD, FACG³, Shanti L. Eswaran, MD, FACG¹. C0279 - Prevalence of Disaccharidase Deficiencies in Adults With Irritable Bowel Syndrome and Functional Diarrhea: Interim Analysis From a Multicenter, Prospective U.S. Trial, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.