Microbial spectrum and antimicrobial resistance are associated with outcomes after endoscopic ultrasound-guided therapy of pancreatic fluid collections.

Infected pancreatic fluid collections (PFC) are among the most challenging entities in therapeutic endoscopy, requiring multiple interventions. In this multicenter study, we investigated whether microbiological profiles and antimicrobial resistance are associated with outcomes after endoscopic ultrasound-guided drainage. The primary endpoint was time to clinical success, defined as radiographic resolution of the PFC to < 30 mm, no need for additional intervention, and clinical improvement. Secondary outcomes included surgery-free survival, number of interventions, and ICU stay. Among 398 included patients (median age: 56.5 years; 70.6% male), 232 (58.3%) had microbiologically confirmed infection. Complete resolution was achieved in 89.2% of infected PFCs (median: 70 days; IQR 37-118) versus 95.2% of sterile PFCs (57 days; IQR 33-91). Resolution was significantly delayed in Enterococcus (n = 107; 26.9%) and polymicrobial resistant infections (n = 38; 9.5%): 87 days (p = 0.003) and 120 days (p < 0.001), respectively. Enterococcus species remained an independent predictor in multivariable Cox regression, and in a sensitivity analysis restricted to the necrosectomy group (aHR 2.50; p = 0.002). Vancomycin-resistant Enterococcus (VRE) infection (n = 26; 6.5%) was associated with the highest number of interventions (median: 6), longest ICU stays (median: 72 days), and highest mortality (23%). In summary, this study identifies an association of Enterococcus species and antimicrobial resistance with poor outcomes after EUS-guided therapy, emphasizing the importance of microbiology-informed treatment strategies.