Microbial profile and putative microbial origin of anorectal abscess

Our study provides a microbiomic panorama and putative microbial origin of anorectal abscess, potentially offering new insights into its etiology, prevention and treatment.We consecutively recruited 60 anorectal abscess patients (AA group) who underwent surgical treatment at the Department of Anorectal Surgery of Yangzhong People's Hospital between October 2023 and June 2024, and enrolled 26 healthy individuals with matched gender and age who were confirmed by the hospital's Health Screening Centre during the same period to serve as a healthy control group (HC group). 16S rDNA sequencing was used to analyse the microbiota in feces, pus and perianal buttock skin samples. The gut microbiota and perianal buttock skin flora were compared between the two groups, the pus flora was analysed in relation to the gut and perianal buttock skin microbiota, and microbial traceability analysis of pus was performed.The results of our study indicate significant differences in gut microbiota between anorectal abscess patients and healthy individuals. Escherichia-Shigella and Prevotella were significantly upregulated and Bacteroides,Faecalibacterium and Blautia were decreased at the genus level in the AA group. Escherichia-Shigella and Prevotella as the main differential bacteria in the AA group can be used as potential biomarkers of anorectal abscess. KEGG analysis also showed significant differences between the two groups, with the AA group being most enriched in protein families: metabolism. No significant difference in the perianal buttock skin flora between anorectal abscess patients and healthy individuals was found in our study. The gut microbiota of anorectal abscess patients is closer to the pus flora than the perianal buttock skin flora, so the gut microbiota is the putative microbial origin of the pus flora.