A case of ulcerative colitis progression after ileostomy reversal following rectal cancer surgery

Introduction

Temporary ileostomy or colostomy is often required in low anterior resection for rectal cancer, especially after neoadjuvant chemoradiotherapy or insufficient blood supply at the anastomosis site. A common complication in these cases is diversion colitis (DC), a nonspecific inflammation of the defunctioned colon. First described in 1972, DC occurs in up to 100% of colonoscopies post-surgery, with around 30% of patients experiencing symptoms like abdominal pain, diarrhea, mucus, or hematochezia [1]. The condition is thought to be caused by the absence of fecal flow, leading to nutrient deficiency, ischemia, immune responses, and microbiota alterations [2]. Ulcerative colitis (UC) and DC share clinical features, particularly in endoscopy, which makes diagnosis challenging and complicates treatment decisions such as restoring fecal flow [3].

In this report, we present a case of a patient diagnosed with low rectal cancer who underwent an ileostomy following surgery. The patient later developed UC following DC. Our objective is to delve deeper into the potential triggers of UC in the context of DC and to examine the criteria for stoma reversal in patients with ileostomies who have been diagnosed with DC.

Case report

A 55-year-old male underwent colonoscopy, revealing rectal cancer 3 cm from the anal verge, with normal rectal mucosa and no inflammation (Figure 1A). The patient had no history or family history of UC. On 19 April 2022, he had a laparoscopic radical resection with an ileostomy. Three months later, colonoscopy showed mild DC (Figure 1B), and ileostomy closure followed on 4 August 2022.

Figure 1.

The clinical data of the case in this study. (A) The remaining intestinal mucosa was normal when rectal cancer is confirmed. (B) The colonic mucosa was presented with mild manifestations of diversion colitis before reversion of ileostomy. (C) Manifestations of colonic mucosa after the first reversion of ileostomy. (D) Mucosal ulcer scar healing and multiple inflammatory polyps. (E) Improved colonic mucosal inflammation and multiple inflammatory polyps before the second reversion of ileostomy. (F) Manifestations of colonic mucosa after second reversion of ileostomy. (G–J) Histopathological examination: chronic inflammation with ulceration [H&E stain, ×100 (G) and ×400 (H)]; chronic inflammation background and atypical manifestations of crypt abscess. [H&E stain, ×100 (I) and ×400 (J)]. The area indicated by the black arrow corresponds to a crypt abscess. H&E = hematoxylin and eosin.

A week after closure, he had bloody stools, frequent bowel movements, intermittent fever, partial intestinal obstruction, and anemia. Colonoscopy revealed extensive colonic mucosal edema, congestion, bleeding points, cobblestone-like changes, ulcers, and erosion (Figure 1C). Clostridium difficile infection was considered due to antibiotic use, and he was treated with rifaximin and vancomycin. But symptoms persisted, and another ileostomy was done. Biopsy indicated chronic active inflammation (Figure 1G and H), and tests for acid-fast bacilli, Cytomegalovirus, and Epstein-Barr virus were negative.

After 1 month of treatment in November 2022, his symptoms improved. Colonoscopy showed severe mucosal edema, cobblestone-like changes, and pseudopolyps, which were slightly better than the previous examination, indicating chronic changes (Figure 1D). He then tried traditional Chinese medicine for over a year. Symptoms reduced, and follow-up colonoscopy in May 2023 showed colon narrowing and inflammatory polyps (Figure 1E). Considering the improvement in colonic mucosal symptoms, the patient expressed a strong desire for stoma closure. His second ileostomy reversal was in February 2024. But a month later, bloody stools and anemia worsened (Figure 1F). Biopsies showed crypt abscesses (Figure 1I and J), suggesting UC rather than DC. At present, he continues to receive vedolizumab maintenance therapy.

Discussion

This report described a case of UC that developed after ileostomy reversal following radical surgery for rectal cancer, which may provide insights into the potential etiology of UC following diversion colitis.

Previous case reports have described four patients who presented with UC in association with diverted colorectal segments, though the exact relationship between DC and UC remains unclear [4]. All had undergone ostomy surgery for benign conditions. Our patient represents the first reported case of UC occurring after ostomy reversal surgery for a malignant rectal tumor. He stands out for the swift progression of their disease and the pronounced inflammatory response observed in the colon and systemically. The development of UC is a multifaceted process that remains not fully elucidated. Deficiencies in the intestinal epithelial barrier, irregularities in immune system response, and disruptions in the gut microbiome are central to the complex dynamics that both initiate and maintain inflammatory activity [3]. Likewise, the fundamental mechanisms underlying DC remain unclear. Glotzer hypothesized that DC could originate from excessive bacterial proliferation, the presence of detrimental bacterial strains, a lack of nutrients, the presence of toxins, or a disruption in the symbiotic interactions between the bacteria in the lumen and the mucosal layer [5]. Analysis of the gut microbiota from both the functional and nonfunctional segments of the stoma through sequencing further substantiates the variations in microbial composition between these two regions [6]. Furthermore, the composition of the gut microbiota is also correlated with the severity of DC [7]. Research has revealed that in the non-functional loop of ileostomies, there is a reduction in Firmicutes and an increase in Proteobacteria, similar to the microbial shifts observed in patients with UC [6, 8]. Furthermore, fecal diversion leads to a deficiency of short-chain fatty acids (SCFAs) and other luminal nutrients required by the colonocytes in the distal colon away from the stoma. This deprivation, or the metabolic disruption caused by alterations in the gut microbiota, may play a role in the development of DC [9]. The reduction of SCFAs leads to a decrease in intestinal energy supply, which, in turn, can impair the function of the mucosal barrier. Additionally, studies have shown that a decrease in SCFAs can result in ischemia of the colonic mucosa and intestinal wall [10]. The impairment of the colonic mucosal barrier, along with the dysregulation of local immune functions, may facilitate the entry of pathogens into the bloodstream through the mucosal, especially when fecal matter is reintroduced into the distal colon following the restoration of bowel continuity. This can trigger both localized and systemic inflammatory responses, which, in turn, can precipitate the development of colitis. The majority of DC patients typically do not see a worsening of colonic inflammation following the restoration of bowel continuity, despite the presence of the aforementioned colonic changes. However, the patient discussed in this report experienced a swift escalation of intestinal inflammation soon after fecal passage, resulting in significant bleeding and a systemic inflammatory response. Throughout the clinical diagnosis and treatment, no infectious or other clear precipitants were identified. Thus, the precise factors that led to this patient's distinct disease trajectory, differing from the majority of DC cases, are not yet understood and require further research.

Authors’ contributions

S.Z. and C.Y. drafted the manuscript. Y.C., M.Y., and Y.Y. collected the patient's medical records. W.S. collected the patient's medical records and funded this research. Z.S. collected the patient's medical records and reviewed and edited the manuscript. All authors have read and approved the final version of the manuscript.

Funding

This work was supported in part by the Beijing Municipal Natural Science Foundation [grant number 7222192].

Conflicts of interest

The authors declared no potential conflicts of interest with respect to the research, authorship, or publication of this article.