Gastrointestinal infections, particularly those caused by Clostridioides difficile, may be a risk factor for microscopic colitis, according to research published in Gastroenterology.
The case-control study included adult patients with microscopic colitis diagnosed in Sweden between 1990 and 2016. A team of investigators matched 13,468 individuals with microscopic colitis with 64,479 individuals from the general population (controls) according to age, sex, calendar year, and county.
The two groups were well matched, with the mean age of participants with microscopic colitis being 60.2 (16.8) years (72% women) and the mean age of controls being 59.6 (16.7) years (72.2% women). The prevalence of previously diagnosed gastrointestinal infection was 7.5% in patients with microscopic colitis, which was significantly higher compared with controls (3.0%, Pcomparison< .001). Gastroenteritis was associated with an increased risk for microscopic colitis (adjusted odds ratio [aOR] 2.63; 95% CI, 2.42-2.85), after adjustment.
Clostridioides difficile (aOR 4.39; 95% CI, 3.42-5.63), Norovirus (aOR 2.87; 95% CI, 1.66-4.87), and Escherichia species (aOR 3.82; 95% CI, 1.22-11.58), but not Salmonella species, were associated with an increased risk for microscopic colitis. The association between gastrointestinal infections and risk of microscopic colitis was stronger for collagenous subtype (aOR 3.23; 95% CI, 2.81-3.70) compared with lymphocytic colitis (aOR = 2.51; 95% CI, 2.28-2.76, Pheterogeneity = .005).
“Our primary finding of an increased association between gastrointestinal infection and risk of microscopic colitis remained consistent across multiple sensitivity and exploratory analyses,” noted the study authors.
The investigators noted several limitations to their findings, including the use of ICD coding to obtain information on gastrointestinal infection, which may be susceptible to underreporting or inaccurate representation of infection type. Also, they did not have information on lifestyle factors that may have confounded the associations and could not assess whether the associations were consistent according to other racial and ethnic groups.
“In a nationwide case-control study we demonstrate that previous diagnosed gastrointestinal infection is associated with an increased risk of microscopic colitis,” the researchers commented. “The associations were particularly stronger for Clostridioides difficile infection and older age [at] diagnosis and collagenous colitis histologic subtype but appeared to be independent of shared genetics and early life factors. Our findings further highlight the role of perturbances in the gut microenvironment in the pathogenesis of microscopic colitis.”
Disclosure: Some of the authors reported affiliations with pharmaceutical and medical diagnostics companies. Please see the original reference for a full list of disclosures.
Khalili H, Axelrad JE, Roelstraete B, Olén O, D’Amato M, Ludvigsson JF. Gastrointestinal infection and risk of microscopic colitis: a nationwide case-control study in Sweden. Gastroenterology. Published online January 6, 2021. doi:https://doi.org/10.1053/j.gastro.2021.01.004