Alterations in the Duodenal Mucosal Mycobiota Associated with Acute Pancreatitis

Objective: The role of gut fungi in pancreatic colonization in patients with acute pancreatitis (AP) is not fully understood. We aimed to determine the structural changes in the duodenal mucosal mycobiota of patients with AP, its association with the disease, and its potential roles. Methods: Thirty-two patients with AP and thirty healthy controls were included in the study. Mucosal samples of the descending duodenum were collected for internal transcribed spacer rRNA sequencing to characterize the fungal communities. Bioinformatic and statistical analyses were performed to analyze community differences, construct prediction models, evaluate clinical correlations, and predict fungal functions. Results: No statistically significant differences in the beta diversity of fungal communities were observed between the groups, while the species-level richness index of alpha diversity showed a significant decrease in the AP group (p < 0.05, q > 0.05). The relative abundances of several fungal taxa differed, with candidate commensals reduced and opportunistic fungi detected sporadically in AP. The prediction model based on fungal taxa preliminary distinguished patients with AP from healthy controls (maximum area under the curve = 0.79). Within the AP cohort, several fungal taxa showed only nominal correlations with inflammatory indicators of AP severity, none of which remained significant after FDR correction. The fungal interaction network was reshaped in AP patients, while core metabolic functions may remain largely unchanged. Conclusions: Patients with AP showed taxon-specific alterations in the duodenal mucosal mycobiota. Differential fungi may be related to the development of disease. Although the potential of fungal microbiota as a candidate biomarker for AP diagnosis and severity assessment requires validation in larger independent cohorts, this study provides a new direction for microecology-targeted interventions in patients with AP.