Objective: Incidence of ulcerative colitis is globally increased. Enteric infections and their role in ulcerative colitis flares present a common health problem and a unique clinical challenge. We aimed to identify enteropathogens in flared ulcerative colitis patients and their antimicrobial susceptibilities and relation with the disease activity.

Methods: Stool samples were collected from 95 patients with ulcerative colitis (17 inactive cases and 78 active cases) according to the Mayo score assessment of ulcerative colitis severity. Enteropathogens were examined using an automated VITEK2 system and FilmArray gastrointestinal pathogen panel.

Results: Enteric infections were found in 81 patients (85.3%) with a significantly higher percentage in active ulcerative colitis (96.2% vs. 35.3%, P < 0.001). In 78 symptomatic patients, (78.7%) of bacteria as enteroaggregative and enteropathogenic E. coli , (11.5%) parasitic as Cryptosporidium and (7.7%) viral as Norovirus were the most detected microbial pathogens. Mixed, multidrug-resistant organisms (MDROs) and opportunistic infections were reported in 70.7%, 52.9% and 46.7% respectively. Raoultella ornithinolytica was reported for the first time as an enteropathogen in ulcerative colitis flare. Multiple organisms, MDROs, extended-spectrum beta-lactamases-producing and AmpC-resistant bacteria were significantly associated with disease severity.

Conclusion: Identifying enteropathogens especially opportunistic and MDR organisms as a cause of ulcerative colitis flare-ups is a matter of worry increasing their diagnostic and therapeutic burden. Periodic studies evaluating changes in microbial profiles and their antimicrobial susceptibilities are needed to achieve antibiotic stewardship and improve management.