Mucosal fungal dysbiosis is associated with early postoperative endoscopic recurrence after bowel resection for Crohn's disease.

Early postoperative endoscopic recurrence occurred in 36.4% of Crohn's disease patients within one year of bowel resection.

• 55 Crohn's disease patients undergoing bowel resection were recruited between October 2022 and February 2024.
• 20 patients (36.4%) developed early postoperative endoscopic recurrence and were assigned to the recurrence group.
• All patients underwent one-year endoscopic follow-up.
• Mucosal samples were obtained during surgery for fungal internal transcribed spacer 1 (ITS1) sequencing.

Preoperative low serum albumin level and elevated postoperative neutrophil-to-lymphocyte ratio were identified as independent risk factors for early postoperative endoscopic recurrence.

• Multivariate analysis was used to identify independent risk factors.
• Two clinical variables — preoperative low serum albumin level and elevated postoperative neutrophil-to-lymphocyte ratio — emerged as significant independent predictors.
• These clinical factors were incorporated alongside fungal biomarkers in the predictive modeling.

The recurrence group exhibited significant mucosal fungal dysbiosis compared to the non-recurrence group.

• The recurrence group showed an increased relative abundance of Basidiomycota.
• An elevated Basidiomycota/Ascomycota ratio was observed in the recurrence group.
• Heightened relative abundances of Malassezia restricta and Debaryomyces hansenii were found in the recurrence group.
• Fungal community characterization was performed using ITS1 sequencing of mucosal samples obtained at the time of surgery.

A combined predictive model integrating three potential fungal biomarkers demonstrated superior predictive performance for early postoperative endoscopic recurrence.

• The combined model integrated three potential fungal biomarkers alongside clinical risk factors.
• Predictive model performance was evaluated using receiver operating characteristic (ROC) curve analysis.
• The combined model incorporating mycobial factors outperformed models based on clinical factors alone.
• The three fungal biomarkers likely included Basidiomycota/Ascomycota ratio, Malassezia restricta, and Debaryomyces hansenii based on the identified associations.

The role of mycobiota in anastomotic recurrence after ileocolectomy for Crohn's disease had previously been unclear prior to this study.

• Anastomotic recurrence after ileocolectomy for Crohn's disease may be related to the gut microbiota, but the role of mycobiota had remained unclear.
• This study aimed to investigate associations between mucosal mycobiota at resection and early postoperative endoscopic recurrence and assess their predictive potential.
• Fungal ITS1 sequencing was employed to characterize fungal communities in mucosal samples.