Introduction

Acute pancreatitis (AP) is an inflammatory disorder that causes a considerable economic health burden. While the majority of AP shows a mild clinical course, about 10% of patients have moderate or severe disease with major local and systemic complications and a prolonged hospital stay. Still there is a lack of early biomarkers of severity while multiple complicated scoring systems fail to predict the course of disease. Here, we aim to investigate the role of the microbiome to predict the course of AP at admission.

Aims & Methods

In 16 European centers buccal and rectal swabs were collected from 450 AP patients within the first 72h of hospital admission. All samples were sequenced with Oxford Nanopore Technologies. Primary endpoints are the association of orointestinal microbiome with revised Atlanta classification and severity. Secondary endpoints are the association with mortality and length of hospital stay.

Results

In total, 832 samples from 424 patients were sequenced, 26 patients met exclusion criteria. After normalization of microbial data 409 buccal samples and 391 rectal samples remained for subsequent analysis. Significant differences were observed in beta diversities for rev. Atlanta classification (Bray Curtis, p-value 0.009**), severity (Bray Curtis, p-value 0.008**), mortality (Bray Curtis, p-value 0.006**) and length of hospital stay (Bray Curtis, p-value 0.043*) in rectal but not buccal swabs. Notably, these results remain significant after factoring in 74 potential confounding variables such as alcohol consumption, smoking status, and antibiotics. No differences were observed in alpha-diversity. Classifier for severity was built with different abundant taxa achieving an AUROC of 80%.

Conclusion

The rectal but not oral microbiome has the ability to predict the course of acute pancreatitis at admission of the patient.