Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 21, 2021; 27(15): 1643-1654
Published online Apr 21, 2021. doi: 10.3748/wjg.v27.i15.1643
Intestinal bacterial overgrowth in the early stage of severe acute pancreatitis is associated with acute respiratory distress syndrome
Xue-Ying Liang, Tian-Xu Jia, Mei Zhang
Xue-Ying Liang, Tian-Xu Jia, Mei Zhang, Department of Gastroenterology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
Author contributions: Liang XY made substantial contributions to the conception and design of the study, acquisition, analysis, and interpretation of data, and drafting the article; Jia TX made substantial contributions to the acquisition and analysis of data; Zhang M made substantial contributions to the conception, design and guide of the study; all authors read and approved the final manuscript.
Supported by Beijing Municipal Education Commission Science and Technology Plan General Project, No. KM201310025015.
Institutional review board statement: The study was reviewed and approved by the Department of Gastroenterology of Xuanwu Hospital, Capital Medical University.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors declare the absence of conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Mei Zhang, PhD, Chief Physician, Doctor, Professor, Department of Gastroenterology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xuanwu District, Beijing 100053, China. zhang2955@sina.com
Received: December 22, 2020
Peer-review started: December 22, 2020
First decision: January 27, 2021
Revised: February 4, 2021
Accepted: March 10, 2021
Article in press: March 10, 2021
Published online: April 21, 2021
Abstract
BACKGROUND

In the early stage of acute pancreatitis (AP), a large number of cytokines induced by local pancreatic inflammation seriously damage the intestinal barrier function, and intestinal bacteria and endotoxins enter the blood, causing inflammatory storm, resulting in multiple organ failure, infectious complications, and other disorders, eventually leading to death. Intestinal failure occurs early in the course of AP, accelerating its development. As an alternative method to detect small intestinal bacterial overgrowth, the hydrogen breath test is safe, noninvasive, and convenient, reflecting the number of intestinal bacteria in AP indirectly. This study aimed to investigate the changes in intestinal bacteria measured using the hydrogen breath test in the early stage of AP to clarify the relationship between intestinal bacteria and acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Early clinical intervention and maintenance of intestinal barrier function would be highly beneficial in controlling the development of severe acute pancreatitis (SAP).

AIM

To analyze the relationship between intestinal bacteria change and ALI/ARDS in the early stage of SAP.

METHODS

A total of 149 patients with AP admitted to the intensive care unit of the Digestive Department, Xuanwu Hospital, Capital Medical University from 2016 to 2019 were finally enrolled, following compliance with the inclusion and exclusion criteria. The results of the hydrogen breath test within 1 wk of admission were collected, and the hydrogen production rates at admission, 72 h, and 96 h were calculated. The higher the hydrogen production rates the more bacteria in the small intestine. First, according to the improved Marshall scoring system in the 2012 Atlanta Consensus on New Standards for Classification of Acute Pancreatitis, 66 patients with a PaO2/FiO2 score ≤ 1 were included in the mild AP (MAP) group, 18 patients with a PaO2/FiO2 score ≥ 2 and duration < 48 h were included in the moderately SAP (MSAP) group, and 65 patients with a PaO2/FiO2 score ≥ 2 and duration > 48 h were included in the SAP group, to analyze the correlation between intestinal bacterial overgrowth and organ failure in AP. Second, ALI (PaO2/FiO2 = 2) and ARDS (PaO2/FiO2 > 2) were defined according to the simplified diagnostic criteria proposed by the 1994 European Union Conference. The MSAP group was divided into two groups according to the PaO2/FiO2 score: 15 patients with PaO2/FiO2 score = 2 were included in group A, and three patients with score > 2 were included in group B. Similarly, the SAP group was divided into two groups: 28 patients with score = 2 were included in group C, and 37 patients with score > 2 were included in group D, to analyze the correlation between intestinal bacterial overgrowth and ALI/ARDS in AP.

RESULTS

A total of 149 patients were included: 66 patients in the MAP group, of whom 53 patients were male (80.3%) and 13 patients were female (19.7%); 18 patients in the MSAP group, of whom 13 patients were male (72.2%) and 5 patients were female (27.8%); 65 patients in the SAP group, of whom 48 patients were male (73.8%) and 17 patients were female (26.2%). There was no significant difference in interleukin-6 and procalcitonin among the MAP, MSAP, and SAP groups (P = 0.445 and P = 0.399, respectively). There was no significant difference in the growth of intestinal bacteria among the MAP, MSAP, and SAP groups (P = 0.649). There was no significant difference in the growth of small intestinal bacteria between group A and group B (P = 0.353). There was a significant difference in the growth of small intestinal bacteria between group C and group D (P = 0.038).

CONCLUSION

Intestinal bacterial overgrowth in the early stage of SAP is correlated with ARDS.

Keywords: Acute respiratory distress syndrome, Hydrogen breath test, Intestinal bacterial overgrowth, Severe acute pancreatitis, Interleukin-6, Acute lung injury

Core Tip: Our retrospective study included 149 patients with acute pancreatic disease. The changes in intestinal flora were detected by the hydrogen breath test. We found that the change in intestinal flora in patients with severe acute pancreatitis was related to acute respiratory distress syndrome, which can aggravate the disease. The results of the hydrogen breath test can be used as a warning signal for severe acute pancreatitis.