Microbial Spectrum and Antibiotic Resistance in Patients Suffering from Penetrating Crohn’s Disease

Abstract

Intraabdominal abscess formation occurs in up to 30% of patients suffering from Crohn´s disease (CD). While international guidelines recommend a step-up approach with a combination of empiric antibiotic therapy and percutaneous drainage to delay or even avoid surgery, evidence about microbial spectrum in penetrating ileitis is sparse. We retrospectively assessed outcomes of 46 patients with terminal penetrating Ileitis where microbial diagnostics have been performed and compared microbial spectrum and antibiotic resistance profile of CD patients with patients suffering from diverticulitis with intraabdominal abscess formation. In both groups, the most frequently isolated pathogen was the gram-negative bacterium E. coli belonging to the family of Enterobacterales. However, overall Enterobacterales were significantly more often verifiable in the control group than in CD patients. Furthermore, microbial analysis showed significant differences regarding isolation of anaerobic pathogens with decreased frequency in patients with CD. Subgroup analysis of CD patients to evaluate a potential influence of immunosuppressive therapy on microbial spectrum only revealed that Enterobacterales was less frequently detected in patients treated with steroids. Immunosuppressive therapy did not show any impact on all other groups of pathogens and did not change antibiotic resistance profile of CD patients. In conclusion, we were able to demonstrate that the microbial spectrum of CD patients does differ only for some pathogen species without increased rate of antibiotic resistance. However, the empiric antibiotic therapy for CD-associated intra-abdominal abscess remains challenging since different points such as local epidemiological and microbiological data, individual patient risk factors, severity of infection, and therapy algorithm including non-surgical and surgical therapy options should be considered before therapeutical decisions are made.

The impact of antibiotic exposure on antibiotic resistance gene dynamics in the gut microbiota of inflammatory bowel disease patients

“…In the transfer networks, Firmicutes, Bacteroidetes, and Proteobacteria harbored the most of the transferred ARGs. Furthermore, consistent with our findings, a retrospective study ( Kusan et al, 2022 ) have demonstrated that antibiotics can induce resistance development in pathogenic E. coli , which belongs to the phylum of Proteobacteria. Notably, genes like vanH, associated with glycopeptide antibiotic resistance ( Marshall et al, 1998 ; Blaskovich et al, 2018 ) were commonly transferred in most individuals, potentially linked to vancomycin use in IBD treatment ( Guinan et al, 2019 ; Lei et al, 2019 ).…”

Disease- and Medication-Specific Differences of the Microbial Spectrum in Perianal Fistulizing Crohn’s Disease—Relevant Aspects for Antibiotic Therapy

“…To further evaluate the potential of antibiotic therapy on perianal fistula formation, results from the ongoing randomized prospective OFF trial (Oral Antibiotics for Anal Abscess) are expected soon (Trial number: NCT03643198) . In regard of fistulizing CD, robust evidence exists on the microbial spectrum of intraabdominal abscesses [ 18 , 19 ], however, little is known about clinically relevant pathogens in perianal fistulizing CD [ 5 ]. Despite that fact, antibiotic treatment is recommended in perianal fistulizing CD, but the applied antibiotics vary relevantly throughout clinical routine, therefore no robust recommendation can be given on the specific antimicrobial type which should be used in those patients.…”