Frequency and predictors of small intestinal bacterial overgrowth in acute pancreatitis

BACKGROUND Acute pancreatitis (AP) is associated with intestinal dysmotility, barrier dysfunction, and dysbiosis, which may increase the risk of small intestinal bacterial overgrowth (SIBO). Evidence on the prevalence of SIBO in AP and its clinical correlates is limited. AIM To evaluate the frequency of SIBO in patients with AP and identify the clinical, laboratory, and imaging predictors of SIBO. METHODS This hospital-based case-control study was conducted at a tertiary gastroenterology unit in New Delhi, India, from December 2022 to June 2024. Consecutive adults with AP were enrolled as cases, and age- and sex-matched healthy controls (HCs) were included. The glucose hydrogen breath test was used for the diagnosis of SIBO. The predictors of SIBO were examined. RESULTS In total, 30 cases and 60 HC were included in the study. SIBO was detected in 12 (40.0%) cases, significantly higher than in HC (1.7%) (P < 0.001). SIBO occurred more frequently in severe AP [4 (100%)] than in moderate-severe AP [6 (75%)] and mild AP [2 (11.1%)] (P = 0.001). Predominant methane producers were more common among AP cases than among HC [12 (40.0%) vs 8 (13.3%); P = 0.004]. Univariate analysis revealed that factors such as abdominal bloating, obstipation, severe pancreatitis, ileus, systemic inflammatory response syndrome, acute necrotic collection, higher computed tomography severity index score, higher neutrophil-lymphocyte ratio, higher creatinine, and elevated high-sensitivity C-reactive protein were associated with SIBO. CONCLUSION SIBO was frequent in AP and was strongly associated with disease severity. Larger prospective studies are required to determine whether identifying and treating SIBO can improve clinical outcomes in AP.