A new study published in Clinical Gastroenterology and Hepatology aimed to ascertain the relationship between appendectomy and microscopic colitis (MC).

This was a population-based case-control study based on the nationwide ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden) cohort. Overall, 14,520 cases of MC and 69,491 controls were selected. Of the participants, 7.6% and 5.1% (n = 3510) had a history of appendectomy ≥1 year before MC or a matching date, respectively.

It was found that patients with a previous appendectomy had a higher predilection for developing MC; this increased susceptibility was consistent for the collagenous colitis subtype or lymphocytic colitis subtype. Further, the risk remained higher throughout follow-up and the highest risk was observed in non-complicated appendicitis.

This nationwide study found a modestly increased risk for MC among patients who have undergone an appendectomy. This associated risk is dependent on the time since appendectomy and the severity of appendicitis. Moreover, despite the associated increased risk for MC, appendectomy may not be a major risk factor for MC predisposition.

Source: Clinical Gastroenterology and Hepatology. 2022 Jun 15;S1542-3565(22)00565-1. doi: 10.1016/j.cgh.2022.05.037.