S1085 Is Pandisaccharidase Deficiency Associated With Small Intestinal Bacterial Overgrowth?

Introduction: Background: Disaccharidases break down complex carbohydrates to facilitate their absorption in the small bowel. Although single disaccharidase enzyme deficiency such as lactase is commonly prevalent, approximately 11% of patients with unexplained gastrointestinal (GI) symptoms have pandisaccharidase deficiency whose etiology is unknown. To examine the relationship of small intestinal bacterial overgrowth (SIBO) in the pathogenesis of pandisaccharidase deficiency. Methods: Patients with unexplained gas, bloating and pain and normal endoscopy/imaging had a 75 g, 2 hour, standard, glucose breath test (GBT), and small bowel aspirates and culture using aseptic precautions, and duodenal biopsies for lactase, sucrase, maltase, palatinase and glucoamylase activity. Those with 3 or more enzyme deficiency (pandeficient) were included in the analysis. The patients' levels of pain, cramping, constipation, belching, bloating, fullness, indigestion, nausea, diarrhea vomiting and flatulence were collected using a validated survey. Results: Fifty-two patients (71% women, mean age 52.88) were identified as pandisaccharidase deficient in a cohort of 497 patients. Among these, lactase deficiency was seen in 90.4%, Maltase in 98.1%, Sucrase in 76.9%, Alpha glucoamylase in 50%, and Palatinase in 98.1%. Of these, 26 (50%) patients had either a positive aspirate (≤20 ppm H2 and/or ≥10 ppm, CH4 rise), indicative of SIBO or small intestinal methanogenic overgrowth (SIMO). Duodenal aspirates were positive in 15 (28.8%) and GBT was positive in 17 (32.7%); 31 had normal GBT. There was no significant difference in symptom profiles between those with SIBO positive and SIBO negative group (P values 0.07-0.79). Conclusion: Approximately 50% of patients with pandisaccharidase deficiency demonstrate evidence for concurrent SIBO/SIMO. These findings suggest a possible etiologic link between small intestinal dysbiosis and carbohydrate malabsorption/intolerance at least in a proportion of patients. This may also explain why symptoms persist in some patients who are treated for either carbohydrate intolerance alone (for example low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols diet) or antibiotics alone for SIBO/SIMO. Recognition of SIBO and its treatment together with dietary modification may be required to improve symptoms in such patients.