Microbial Dynamics of Acute Pancreatitis: Integrating Culture, Sequencing, and Bile Impact on Bacterial Populations and Gaseous Metabolites.. Pancreatic fluid

Background:Our study examined the composition of the intestinal microflora in a hospitalized patient with AP symptoms treated several months earlier for diverticulitis. The therapeutic intervention necessitated Hartmann's procedure, culminating in colostomy creation.Aims:Employing a thorough microbiological analysis we attempted to demonstrate whether the microflora isolated from the peripancreatic fluid exhibited a stronger correlation with the contents of the stoma or with the rectal swab. Additionally, we sought to determine the association between later onset of AP and diverticulitis.Methods:Following clinical materials from the patient in the initial phase of AP were collected: rectal swab, colostomy bag contents contents (in the publication referred to as stoma content/stool) and peripancreatic fluid. Microbiological analysis was performed, including classic culture methodology, NGS techniques, and genotyping methodologies. Furthermore, the effect of bile on the shift in the population of selected bacterial species was examined.Results:The NGS technique confirmed greater consistency in bacteria percentage (phyla/family) between stoma content and peripancreatic fluid. In both samples, a clear dominance of the Proteobacteria phyla (over 75%) and the Enterobacteriaceae family was demonstrated. Moreover, NGS verified the presence of the Fusobacteriota phylum and Fusobacteriaceae family only in rectal swabs, which may indicate a link between this type of bacteria and the etiology of diverticulitis. We observed that Escherichia coli 33 isolated from stool exhibited active gaseous metabolite production (mainly hydrogen).Conclusions:The abundant production of hydrogen may substantially impact enzymatic processes, inducing specific alterations in disulfide bonds and trypsin inactivation. Our investigation alludes to the conceivable active involvement of bile in effecting qualitative and quantitative modifications in the peripancreatic microbiota composition, establishing a correlation between released bile and bacterial generation of gaseous metabolites.

背景：本研究针对一名数月前因憩室炎接受治疗，后因急性胰腺炎（AP）症状住院的患者，分析其肠道菌群组成。该患者此前的治疗干预需实施哈特曼手术，最终完成了结肠造口术。
研究目的：通过全面的微生物学分析，旨在明确从胰周液中分离得到的菌群，与结肠造口内容物或直肠拭子菌群的相关性更强。此外，本研究还试图明确迟发性急性胰腺炎与憩室炎之间的关联。
研究方法：收集该急性胰腺炎初发期患者的临床样本，包括直肠拭子、结肠造口袋内容物（本文中称造口内容物/粪便）以及胰周液。采用经典培养法、下一代测序（Next-Generation Sequencing，NGS）技术以及基因分型方法开展微生物学分析。此外，本研究还探讨了胆汁对特定细菌种群结构变化的影响。
研究结果：下一代测序（NGS）技术证实，造口内容物与胰周液的细菌占比（菌门/菌科水平）一致性更高。两类样本中均检出变形菌门（Proteobacteria，占比超75%）和肠杆菌科（Enterobacteriaceae）的显著优势定植。此外，NGS验证仅在直肠拭子样本中检出梭杆菌门（Fusobacteriota）和梭杆菌科（Fusobacteriaceae），这提示此类细菌或与憩室炎的病因存在关联。本研究观察到，从粪便中分离得到的大肠杆菌（Escherichia coli）33株可活跃产生气体代谢产物（主要为氢气）。
研究结论：大量氢气的产生可对酶促反应过程产生显著影响，诱导二硫键发生特异性改变并导致胰蛋白酶失活。本研究提示，胆汁或可主动参与调控胰周菌群组成的质与量变化，证实了释出的胆汁与细菌产生气体代谢产物之间存在关联。