The clinical and microbiological burden of gastrointestinal fistulas in patients with infected pancreatic necrosis: a retrospective study.

BACKGROUND

Gastrointestinal fistula (GIF) is a well-recognized complication of infected pancreatic necrosis (IPN). However, the evidence on the effect of GIF remains limited. This study aimed to investigate incidence, risk factors, microbiological profiles, and clinical outcomes of GIF in a large cohort of patients with IPN.

METHODS

A post hoc analysis was conducted using data from a large prospective database involving 385 patients with IPN between January 2011 and April 2025. A comparative analysis of the clinical and microbiological characteristics, surgical management, and follow-up data was performed for patients with IPN with and without GIF.

RESULTS

Of 385 patients with IPN, 62 (16.1%) developed GIF. Compared with patients without GIF, those with GIF exhibited higher rates of polymicrobial infection (59.4% vs 79.0%, respectively; P =.004), multidrug-resistant fungi (14.9% vs 27.4%, respectively; P =.016), carbapenem-resistant Enterobacteriaceae (CRE; 25.1% vs 40.3%, respectively; P =.014), carbapenem-resistant Klebsiella pneumoniae (CRKP; 32.5% vs 56.5%, respectively; P <.001), and fungal infections (23.2% vs 40.3%, respectively; P =.005). In addition, bloodstream infections from multidrug-resistant organisms and CRE were more common in patients with GIF than in those without GIF (multidrug-resistant organisms: 35.5% vs 15.5%, respectively; P <.001; CRE: 27.4% vs 6.5%, respectively; P <.001). GIF development was associated with more frequent adoption of open necrosectomy (35.5% in the GIF group vs 14.9% in the non-GIF group; P <.001), longer duration of organ failure (median: 10.5 days in the GIF group vs 3.0 days in the non-GIF group; P =.048), higher incidence of severe acute pancreatitis (69.4% in the GIF group vs 55.1% in the non-GIF group; P =.038), prolonged hospital stay (median: 96.0 days in the GIF group vs 75.5 days in the non-GIF group; P =.007), and an increased hemorrhage rate (35.5% in the GIF group vs 18.6% in the non-GIF group; P =.003). In addition, mortality was significantly higher in patients with GIF than in those without GIF (22/62 [35.5%] vs 70/323 [21.7%]; P =.019). Multivariate analysis revealed multiple organ failure (MOF) as an independent predictor of mortality in patients with GIF (odds ratio, 27.97 [95% CI, 2.35-332.89]; P =.008).

CONCLUSION

GIF affected 16.1% of patients with IPN and was associated with adverse outcomes. MOF predicted higher mortality for patients with IPN and GIF. CRE, particularly CRKP, is a crucial pathogen that requires urgent attention.