Ulcerative Colitis and Diverticulitis Are Possibly Connected to the Same Hub

To the Editors, We read the report from Dr. Veloso titled, “Are Ulcerative Colitis and Diverticulitis Collected by the Same Hub?” with great interest. This is an interesting case that shares a similar clinical experience of developing de novo inflammatory bowel disease (IBD) after diverticulitis in a young patient. The described patient had an episode of complicated diverticulitis requiring surgical intervention. Seven years later, he developed ulcerative proctitis, which later progressed to symptomatic distal colitis. The current treatments for inflammatory bowel disease focus on mitigating the sequela of chronic inflammation; however, there remains a knowledge gap of complex environmental factors coupled with genetic susceptibility that interplays in the pathogenesis of IBD. There has been an increasing incidence of IBD and diverticulitis among the younger population in industrialized countries, suggesting shared environmental factors in the pathogenesis of these 2 clinical entities. Reduced dietary fiber intake, processed food, break-in mucosal integrity, and possible antibiotic exposure as part of complicated diverticulitis treatment contribute to gut microbiota dysbiosis and intestinal inflammation.1,2 Although our study did not include smoking cessation as one of the risk factors, multiple studies have shown that former smokers have a significantly high risk of ulcerative colitis development.3,4 Therefore, it is conceivable that smoking cessation could be one of the environmental determinants for IBD. As opposed to our study in which most patients had ulcerative pancolitis with some patients requiring biologics and surgical intervention, the presented case had distal colitis controlled with 5-ASA regimen. Still, it should be pointed out that ulcerative colitis has a relapsing and remitting course with nonexistent data on the long-term clinical course of IBD in patients who had a prior episode of complicated diverticulitis.5 We believe that with the evidence of growing literature, such as the case presented by Veloso et al, more extensive prospective studies with extended follow-up data and microbiome analysis would help to understand the risk factors and pathogenesis of IBD development after episodes of complicated diverticulitis. Identifying individuals at high risk for IBD development potentially allows close monitoring and early intervention to check disease progression.