急性胰腺炎患者胰腺周围坏死脓液的宏基因组景观：病原体生态、耐药基因谱及疾病相关微生物模式

Abstract

Objective To characterize the metagenomic landscape of intra-abdominal pus from surgical ICU patients using metagenomic next-generation sequencing (mNGS), compare pathogen ecology and resistance gene profiles between acute pancreatitis (AP)-associated and non-pancreatitis abdominal infection, and examine the association between pancreatitis-associated microbial features and persistent organ failure status. Methods A total of 115 patients undergoing abdominal paracentesis and drainage in a surgical ICU were stratified into three groups: the POF group (AP with persistent organ failure, n = 35), the Non-POF group (AP without persistent organ failure, n = 49), and the Non-AP group (non-pancreatitis intra-abdominal infection, n = 31). Pus samples were analyzed by mNGS to characterize pathogen profiles, antimicrobial resistance gene (ARG) carriage, and microbial community structure. Results Compared with Non-AP infections, both AP groups showed a convergent microbial profile dominated by ICU-associated pathogens, including Enterococcus faecium , Klebsiella pneumoniae , Acinetobacter baumannii complex, and Pseudomonas aeruginosa , with broad ARG detection profiles. ARG positivity was higher in AP patients than Non-AP controls (69.0% vs. 45.2%; P = 0.029), with frequent detection of Beta-lactam resistance genes, including carbapenemase-related genes. At sampling, alpha and beta diversity did not differ between POF and Non-POF groups, whereas both AP groups were clearly separated from Non-AP infections ( P < 0.01). Among species enriched in Non-AP pus, Enterococcus faecalis remained inversely associated with AP status after adjustment for comorbidity burden, disease severity, antibiotic exposure, and ICU exposure (all P ≤ 0.006). The family-level random forest model achieved exploratory discriminatory performance for AP identification (AUC = 0.843). Conclusion AP-associated peripancreatic pus harbored a distinct microbial ecological profile characteriz