P2361 - Examining The Relationships of Small Bowel and Colonic Bacterial Burden Using Area Under the Curve to Symptoms of Small Intestinal Bacterial Overgrowth (SIBO) in the Lactulose Breath Test
Samyuktha Manikandan, MD1, Abraham Ifrah, MD1, John Ebeid, MD1, Daniel Rim, MD2, Henry P. Parkman, MD3 1Temple University Hospital, Philadelphia, PA; 2Lewis Katz School of Medicine at Temple University, Philadelphia, PA; 3Temple University, Strafford, PA
Introduction: The lactulose breath test (LBT) is a non-invasive, cost-effective tool commonly used to diagnose small intestinal bacterial overgrowth (SIBO), which is associated with gastrointestinal symptoms such as abdominal bloating, diarrhea, and abdominal distention. The relationship between colonic bacterial burden and SIBO-associated symptoms remains unexplored. Further, no study examines the bacterial burden using the area under the curve with numerous symptoms. This study investigates the association between bacterial burden in both the small bowel and the colon with SIBO symptoms.
Methods: In this retrospective study of 126 patients undergoing LBT, SB bacterial burden was estimated using AUC for H2 and CH4 levels in the initial 90 minutes post-lactulose. Colonic bacterial burden was assessed using AUC for H2 and CH4 levels from 90 to 180 minutes post-lactulose. Symptoms of SIBO were evaluated with a 24-item questionnaire administered during LBT, aiming to correlate SB and colonic bacterial burdens with SIBO symptoms.
Results: The average AUC are as follows: baseline H2 24.9, CH4 36.5; first 90 minutes H2 1359.4, CH4 1119.9; 90-180 minutes H2 3875.9, CH4 1724.8. The relationship between SB and colonic bacterial burden and symptoms concerning for SIBO are summarized in Table 1. Among the 24 symptoms assessed, the strongest correlations with SB and colonic bacterial burdens include: nausea (CH4 SB r=0.18, p=0.040), stomach fullness (H2 SB r=0.17, p=0.058; CH4 SB r=0.17, p=0.064; CH4 colonic r=0.16, p=0.082), stomach distention (H2 SB r=0.15, p=0.087), and upper abdominal discomfort (CH4 SB r=0.17, p=0.064).
Discussion: This study used the AUC method to examine bacterial burdens in the small bowel (SB) and colon, correlating them with 24 symptoms. It found a significant link between nausea and methanogen bacterial burden in the SB. Additionally, there was a subtle correlation between stomach fullness and bacterial burdens of H2 and CH4-producing bacteria in the SB, and methane-producing bacteria in the colon. A slight association was also noted between stomach distention and H2 -producing bacteria in the SB. Upper abdominal discomfort was linked with methanogen bacterial burden in the SB. These findings suggest that symptoms like nausea, stomach fullness, stomach distention, and upper abdominal discomfort are closely related to bacterial burdens in the small bowel, with some association seen with colonic bacterial burden and stomach fullness.
Note: The table for this abstract can be viewed in the ePoster Gallery section of the ACG 2024 ePoster Site or in The American Journal of Gastroenterology's abstract supplement issue, both of which will be available starting October 27, 2024.
Disclosures:
Samyuktha Manikandan indicated no relevant financial relationships.
Abraham Ifrah indicated no relevant financial relationships.
John Ebeid indicated no relevant financial relationships.
Daniel Rim indicated no relevant financial relationships.
Samyuktha Manikandan, MD1, Abraham Ifrah, MD1, John Ebeid, MD1, Daniel Rim, MD2, Henry P. Parkman, MD3. P2361 - Examining The Relationships of Small Bowel and Colonic Bacterial Burden Using Area Under the Curve to Symptoms of Small Intestinal Bacterial Overgrowth (SIBO) in the Lactulose Breath Test, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.
