Gut colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae may increase disease activity in biologic-naive outpatients with ulcerative colitis: an interim analysis

<jats:sec> <jats:title>Background</jats:title> <jats:p>Certain <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> strains have been associated with the development of ulcerative colitis (UC). Extended-spectrum β-lactamase (ESBL)-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> are the most commonly found multi-drug-resistant (MDR) bacteria colonizing the gut in UC patients and might trigger a more severe disease activity in UC patients.</jats:p> </jats:sec> <jats:sec> <jats:title>Objective</jats:title> <jats:p>The aim of this study was to evaluate whether disease activity is higher in UC patients with gut colonization with ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic>.</jats:p> </jats:sec> <jats:sec> <jats:title>Materials and methods</jats:title> <jats:p>A cross-sectional, pilot study was carried out in a tertiary medical center in Latvia. Demographic data were collected; UC disease activity and extent were evaluated according to the full Mayo score, Montreal classification, and adapted Truelove and Witt’s index. Rectal swabs with fecal biomaterial were collected, ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> were isolated, and bacterial plasmid genes responsible for ESBL production, <jats:italic toggle="yes">blaCTX-M</jats:italic>, <jats:italic toggle="yes">blaTEM</jats:italic>, and <jats:italic toggle="yes">blaSHV</jats:italic>, were detected. UC disease activity was compared in patients with and without gut colonization with ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae.</jats:italic> </jats:p> </jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>A total of 65 patients with UC were included in the initial analysis. Gut colonization with ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> was found in seven (11%) patients – mostly <jats:italic toggle="yes">Escherichia coli</jats:italic> [5 (71%)] containing the <jats:italic toggle="yes">blaCTX-M</jats:italic> bacterial plasmid gene. Patients with gut colonization with ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> had more severe disease compared with patients without gut colonization according to the full Mayo score (5.86 vs. 3.40; <jats:italic toggle="yes">P</jats:italic>=0.015), Montreal classification (moderate disease vs. clinical remission; <jats:italic toggle="yes">P</jats:italic>=0.031), and adapted Truelove and Witt’s index (moderate disease vs. mild disease; <jats:italic toggle="yes">P</jats:italic>=0.008).</jats:p> </jats:sec> <jats:sec> <jats:title>Conclusion</jats:title> <jats:p>Gut colonization with ESBL-producing <jats:italic toggle="yes">Enterobacteriaceae</jats:italic> may increase UC disease activity. Further research is needed to analyze the possible confounding factors that could contribute toward this outcome.</jats:p> </jats:sec>