Differences in Prognosis and Recurrence Patterns Between Ulcerative Colitis-Associated Colorectal Cancer and Sporadic Colorectal Cancer: A Matched-Pair Analysis.

BACKGROUND: Clinicopathological differences exist between ulcerative colitis-associated colorectal cancer (UC-CRC) and sporadic colorectal cancer (S-CRC). However, differences in the prognosis remain controversial, and the reason for these differences remains unclear. We therefore assessed the differences between patients with UC-CRC and S-CRC. PATIENTS AND METHODS: This was a matched-pair analysis of the clinicopathological characteristics and prognosis of patients with UC-CRC and S-CRC who underwent colorectal resection between January 2000 and December 2021 at two institutions. Patients were matched according to age, sex, date of surgery, tumor location, and Union for International Cancer Control (UICC) stage. RESULTS: A total of 5992 patients underwent surgery for CRC at the two institutions, and 288 patients (48 with UC-CRC and 240 with S-CRC) were matched in this study. Patients with UC-CRC underwent more invasive surgery and had a longer operative time than those with S-CRC, but there was no marked difference in postoperative complications or perioperative mortality. Long-term outcomes showed a similar 5-year overall survival (OS) for UC-CRC and S-CRC (86.5% versus 88.8%, p = 0.742); however, in stage 3 patients, patients with UC-CRC had a poorer 5-year OS than those with S-CRC (51.4% versus 83.8%, p = 0.032). The first recurrence sites in stage 3 UC-CRC were peritoneal dissemination followed by the bones, while those in S-CRC were the liver and pulmonary system. CONCLUSIONS: Despite no significant differences in surgical outcomes, patients with UC-CRC had a poorer prognosis than those with S-CRC at stage 3. The recurrence patterns in UC-CRC differed from those in S-CRC, suggesting a possible prognostic difference.

Clinical and histological impact of diffuse inflammation at pouchoscopy.

PURPOSE: The anatomical location of inflammation in and around the ileal pouch affects the pouch survival rate, and diffuse inflammation has poor pouch survival rates. We aimed to clarify the symptoms and histological findings of diffuse inflammation of the pouch. METHODS: We evaluated the symptoms, treatment, and histological findings according to the endoscopic phenotypes of diffuse inflammation, focal inflammation, and normal as the pouch body phenotype and afferent limb involvement, inlet involvement, cuffitis, and fistula as the peripheral findings. RESULTS: Of the 318 pouchoscopies, 47 had diffuse inflammation, 201 had focal inflammation, and 70 were normal. Symptomatic patients had diffuse inflammation more frequently (46.8%) than focal inflammation (13.4%) and normal (14.2%), with no difference between focal inflammation and normal. Antibiotics and steroids were higher rate administered in cases of diffuse inflammation, but not in cases of focal inflammation or in normal cases. Histological inflammation, inflammatory bowel disease (IBD)-specific finding, and colonic metaplasia showed severity in the order of diffuse inflammation > focal inflammation > normal. The number of peripheral inflammatory findings overlapped in the following order: diffuse inflammation > focal inflammation > normal. The number of symptomatic patients increased as the number of peripheral inflammatory findings increased. CONCLUSION: Pouches with diffuse inflammation are more symptomatic, have a higher use of therapeutic agents, and have more severe histological inflammation, IBD-specific finding, and colonic metaplasia accompanying peripheral inflammatory findings than the other groups. The higher the overlap of inflammatory findings in the surrounding tissues, the more symptomatic the patients will appear.

Usefulness of Hand-assisted Laparoscopic Restorative Proctocolectomy for Ulcerative Colitis in the Era of Laparoscopic Surgery - A Single-center Observational Study.

Objectives: Hand-assisted laparoscopic surgery (HALS) combines the benefits of laparoscopic surgery with the tactile feedback from open surgery. In the current era of laparoscopic surgery, the significance of HALS as a technical transition has diminished. This study clarified the usefulness of HALS in restorative proctocolectomy (RPC) for ulcerative colitis (UC) in the era of laparoscopic surgery. Methods: The 212 patients who underwent RPC with ileal pouch-anal anastomosis between 2007 and 2023 were included in this study. The patients were divided into three groups, open surgery (OS), HALS, and conventional laparoscopic surgery (LAP), and their characteristics, surgical outcomes, surgical complications, and functional outcomes were compared. Results: The number of surgical techniques was OS in 21 cases, HALS in 184 cases, and LAP in 7 cases. The number of surgeons was two for OS and HALS, and four for LAP, with OS and HALS having fewer surgeons than LAP. The length of the skin incision was 13, 7, and 3 cm for OS, HALS, and LAP, respectively, and the operation times was 250, 286, and 576 minutes for OS, HALS, and LAP, respectively, with LAP having the longest operation time. The postoperative complications and function did not differ markedly among the three groups. Conclusions: In RPC for UC, HALS involved fewer surgeons and a shorter operative time than LAP. Even in the era of laparoscopic surgery, HALS remains a useful option, especially when a shorter operation time is required or when the number of available surgeons is insufficient.

Massive bleeding and perforation due to post-colectomy pan-enteritis with a significant response to biologic in a patient with ulcerative colitis: a case report.

BACKGROUND: Post-colectomy pan-enteritis in ulcerative colitis (UC) is very rare, but it is often severe and fatal. We present a case of massive bleeding and perforation due to post-colectomy pan-enteritis, which showed a significant response to biologics in a UC patient. CASE PRESENTATION: A 30-year-old woman with a 5-month history of pancolitis UC underwent subtotal colectomy with ileostomy and mucosal fistula for refractory UC. She was diagnosed with small bowel obstruction on postoperative day (POD) 8 and bowel bleeding was observed on POD18. Reoperation was performed for bowel obstruction and bleeding on POD20. Intraoperatively, adhesive small bowel obstruction in the ileum and multiple erosions and ulcers with perforation were observed throughout the small bowel. We diagnosed post-colectomy pan-enteritis, and jejunostomy, lavage, adhesiolysis, and a simple closure of the perforated ileum were performed. High-dose steroid therapy for pan-enteritis was administered immediately after reoperation, and infliximab was administered because of worsening bleeding on day 3 after reoperation. Bleeding decreased one day after biologic administration and bleeding completely disappeared on day 10 after biologic administration. Specimens obtained from the terminal ileum at colectomy showed a normal ileum without inflammation and villus atrophy, while specimens from the perforated ileum showed congestion, villous atrophy, epithelial erosion, and mononuclear cell infiltration. No cryptitis, crypt distortion, or basal plasmacytosis (common characteristics in UC) were observed in either specimen. CONCLUSION: An early diagnosis and intervention are important for post-colectomy pan-enteritis, and infliximab may be effective. Post-colectomy pan-enteritis with a multiple ulcer phenotype has different histological characteristics from UC and may have a different pathogenesis.

Intestinal ultrasound for intestinal Behçet disease reflects endoscopic activity and histopathological findings.

BACKGROUND/AIMS: Intestinal Behçet disease is typically associated with ileocecal punched-out ulcers and significant morbidity and mortality. Intestinal ultrasound is a noninvasive imaging technique for disease monitoring. However, no previous reports have compared intestinal ultrasound with endoscopic ulcer activity or histopathological findings for intestinal Behçet disease. We evaluated the usefulness of intestinal ultrasound for assessing the activity of ileocecal ulcers in intestinal Behçet disease. METHODS: We retrospectively compared intestinal ultrasound findings with 73 corresponding endoscopic images and 6 resected specimens. The intestinal ultrasound findings were assessed for 7 parameters (bowel wall thickness, vascularity [evaluated using the modified Limberg score with color Doppler], bowel wall stratification, white-plaque sign [strong hyperechogenic lines or spots], mesenteric lymphadenopathy, extramural phlegmons, and fistulas), and endoscopic ulcer activity was classified into active, healing, and scar stages. Histopathological findings were evaluated by consensus among experienced pathologists. RESULTS: Bowel wall thickness (P< 0.001), vascularity (P< 0.001), loss of bowel wall stratification (P= 0.015), and white-plague sign (P= 0.013) were significantly exacerbated in the endoscopic active ulcer stage. Receiver operating characteristic curve analysis revealed that a bowel wall thickness of > 5.5 mm (sensitivity 89.7%, specificity 85.3%) was potentially useful for detecting active lesions. When compared with histopathological findings, an increase in bowel wall thickness reflected the ulcer marginal ridge, and the white-plaque sign reflected the ulcer bottom. CONCLUSIONS: Intestinal ultrasound is useful for monitoring intestinal ulcer activity in intestinal Behçet disease.

Histological differentiation between sporadic and colitis-associated intestinal cancer in a nationwide study: A propensity-score-matched analysis.

BACKGROUND AND AIM: Colitis-associated intestinal cancer (CAC) can develop in patients with inflammatory bowel disease; however, the malignant grade of CAC may differ from that of sporadic colorectal cancer (CRC). Therefore, we compared histological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC. METHODS: We reviewed the clinical and histological data collected from a nationwide database in Japan between 1983 and 2020. Patient characteristics were compared to distinguish ulcerative colitis (UC), Crohn's disease (CD), and sporadic CRC. Comparisons were performed by using all collected data and propensity score-matched data. RESULTS: A total of 1077 patients with UC-CAC, 297 with CD-CAC, and 136 927 with sporadic CRC were included. Although the prevalence of well or moderately differentiated adenocarcinoma (Tub1 and Tub2) decreased according to tumor progression for all diseases (P < 0.01), the prevalence of other histological findings, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, or squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histological findings other than Tub1 and Tub2 was also significantly higher in those with CAC. At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 [52.3%]) than in those with sporadic CRC (13/88 [14.8%]) (P < 0.01). CONCLUSION: CAC, including early-stage CAC, has a higher malignant grade than sporadic CRC, and this difference increases in significance with tumor progression.

Crohn's Disease-Associated Anorectal Cancer Has a Poor Prognosis With High Local Recurrence: A Subanalysis of the Nationwide Japanese Study.

INTRODUCTION: Colorectal cancer (CRC) is one of the major life-threatening complications in patients with Crohn's disease (CD). Previous studies of CD-associated CRC (CD-CRC) have involved only small numbers of patients, and no large series have been reported from Asia. The aim of this study was to clarify the prognosis and clinicopathological features of CD-CRC compared with sporadic CRC. METHODS: A large nationwide database was used to identify patients with CD-CRC (n = 233) and sporadic CRC (n = 129,783) over a 40-year period, from 1980 to 2020. Five-year overall survival (OS), recurrence-free survival (RFS), and clinicopathological characteristics were investigated. The prognosis of CD-CRC was further evaluated in groups divided by colon cancer and anorectal cancer (RC). Multivariable Cox regression analysis was used to adjust for confounding by unbalanced covariables. RESULTS: Compared with sporadic cases, patients with CD-CRC were younger; more often had RC, multiple lesions, and mucinous adenocarcinoma; and had lower R0 resection rates. Five-year OS was worse for CD-CRC than for sporadic CRC (53.99% vs 71.17%, P < 0.001). Multivariable Cox regression analysis revealed that CD was associated with significantly poorer survival (hazard ratio 2.36, 95% confidence interval: 1.54-3.62, P < 0.0001). Evaluation by tumor location showed significantly worse 5-year OS and RFS of CD-RC compared with sporadic RC. Recurrence was identified in 39.57% of CD-RC cases and was mostly local. DISCUSSION: Poor prognosis of CD-CRC is attributable primarily to RC and high local recurrence. Local control is indispensable to improving prognosis.

Serrated polyps in patients with ulcerative colitis: Unique clinicopathological and biological characteristics.

BACKGROUND: Serrated polyps have recently been reported in patients with ulcerative colitis (UC); however, their prevalence and detailed characteristics remain unclear. METHODS: The prevalence and clinicopathological and biological characteristics of serrated polyps in patients with UC were retrospectively examined in a single tertiary inflammatory bowel disease center in Japan from 2000 to 2020. RESULTS: Among 2035 patients with UC who underwent total colonoscopy, 252 neoplasms, including 36 serrated polyps (26 in colitis-affected segments, 10 in colitis-unaffected segments), were identified in 187 patients with UC. The proportion of serrated polyps was 1.8% (36/2035). Serrated polyps in colitis-affected segments were common with extensive colitis (88%), history of persistent active colitis (58%), and long UC duration (12.1 years). Serrated polyps in colitis-affected segments were more common in men (88%). Of the 26 serrated polyps in colitis-affected segments, 15, 6, and 5 were categorized as sessile serrated lesion-like dysplasia, traditional serrated adenoma-like dysplasia, and serrated dysplasia not otherwise specified, respectively. Sessile serrated lesion-like dysplasia was common in the proximal colon (67%) and with BRAF mutation (62%), whereas traditional serrated adenoma-like dysplasia and serrated dysplasia not otherwise specified were common in the distal colon (100% and 80%, respectively) and with KRAS mutations (100% and 75%, respectively). CONCLUSIONS: Serrated polyps comprised 14% of the neoplasias in patients with UC. Serrated polyps in colitis-affected segments were common in men with extensive and longstanding colitis, suggesting chronic inflammation in the development of serrated polyps in patients with UC.

Curable leakage in stapled IPAA has little effect on the long-term pouch function.

PURPOSE: This study aimed to evaluate the frequency and grade of anastomotic leakage (AL) in stapled ileal pouch-anal anastomosis (IPAA) and its long-term impact on the pouch functions. METHODS: A longitudinal cohort study was conducted on UC patients who underwent stapled IPAA at Yokohama City University Medical Center between 2007 and 2018. The diagnosis and grading of AL were performed in accordance with the recommendations of the International Study Group of Rectal Cancer. We assessed the functional pouch rate, late complication, pouch survival rate, bowel function (bowel movements per day, soiling, spotting, difficulty in distinguishing feces from flatus) and pouch inflammation (pouchitis disease activity index; PDAI) in the long-term period. RESULTS: Two hundred seventy-six patients were analyzed. Twenty-three (8.3%; grade B/C; 13/10) patients were diagnosed with AL, but a functional pouch was achieved in all the twenty-three patients. Anastomotic stricture was significantly more common in patients with AL (AL group) than in patients without AL (non-AL group; AL/non-AL: 13.0/3.2%, p = 0.020). There were no differences in other late complications. Furthermore, the pouch survival rate did not differ between the AL and non-AL groups (100.0/97.9%/10 years, p = 0.494). There were no differences between the groups in bowel movements per day, spotting, soling, difficulty in distinguishing feces from flatus, or PDAI postoperatively. CONCLUSIONS: Curable AL may not affect late complications (except anastomotic stricture), pouch survival, the bowel function, or pouch inflammation over the long term. Perioperative management to prevent the severity of AL is as important as preventing its occurrence.

Impact of the body mass index on the retention of the anorectal mucosa after double-stapled ileal pouch-anal anastomosis for ulcerative colitis.

BACKGROUND: Double-stapled ileal pouch-anal anastomosis (DS-IPAA) is easy to construct and has a good functional outcome in patients with ulcerative colitis (UC). However, retention of the anorectal mucosa may lead to a subsequent risk of inflammation and neoplasia. This study aimed to identify factors associated with the retention of a large amount of anorectal mucosa after DS-IPAA. METHODS: The medical records of 163 patients who had undergone one-stage total proctocolectomy and DS-IPAA for UC between 2007 and 2020 were retrospectively reviewed. The patients were divided into two groups according to the length of the retained mucosa. The high anastomosis group was defined as having a retained mucosal length of ≥ 30 mm in the anterior or posterior wall. Clinical factors were compared between the high and low anastomosis groups. RESULTS: The high anastomosis group showed a significantly higher body mass index (BMI) (high vs. low: 23.2 vs. 19.0), longer operation time (304 vs. 263) and greater blood loss (357 vs. 240). In the multivariate analysis, high BMI was the only factor significantly associated with high anastomosis (odds ratio 1.32). There was a positive correlation between BMI and the length of the retained mucosa. CONCLUSIONS: In DS-IPAA, BMI showed the strongest association with the retention of a large amount of the anorectal mucosa. In high BMI patients, although the risk of inability of anastomosis is little than that of IPAA with mucosectomy, the possible retention of a large amount of mucosa should be considered.

Effect of Biologics on the Risk of Advanced-Stage Inflammatory Bowel Disease-Associated Intestinal Cancer: A Nationwide Study.

INTRODUCTION: The aim of this study was to evaluate the effect of biologics on the risk of advanced-stage inflammatory bowel disease (IBD)-associated intestinal cancer from a nationwide multicenter data set. METHODS: The medical records of patients with Crohn's disease (CD) and ulcerative colitis (UC) diagnosed with IBD-associated intestinal neoplasia (dysplasia or cancer) from 1983 to 2020 were included in this study. Therapeutic agents were classified into 3 types: biologics, 5-aminosalicylic acid, and immunomodulators. The pathological cancer stage was compared based on the drug used in both patients with CD and UC. RESULTS: In total, 1,042 patients (214 CD and 828 UC patients) were included. None of the drugs were significantly associated with cancer stage in the patients with CD. In the patients with UC, an advanced cancer stage was significantly associated with less use of biologics (early stage: 7.7% vs advanced stage: 2.0%, P < 0.001), 5-aminosalicylic acid, and immunomodulators. Biologic use was associated with a lower incidence of advanced-stage cancer in patients diagnosed by regular surveillance (biologics [-] 24.5% vs [+] 9.1%, P = 0.043), but this was not the case for the other drugs. Multivariate analysis showed that biologic use was significantly associated with a lower risk of advanced-stage disease (odds ratio = 0.111 [95% confidence interval, 0.034-0.356], P < 0.001). DISCUSSION: Biologic use was associated with a lower risk of advanced IBD-associated cancer in patients with UC but not with CD. The mechanism of cancer progression between UC and CD may be different and needs to be further investigated.

Appropriate Preconception Corticosteroid-Free Remission Period in Pregnant Women With Ulcerative Colitis.

BACKGROUND: In women with inflammatory bowel disease, at least 3 months of preconception corticosteroid-free remission (CFREM) is recommended by experts in current consensus statements. However, data are lacking on the appropriate preconception remission period. We investigated the appropriate preconception CFREM period in women with ulcerative colitis to reduce maternal disease activity and adverse pregnancy outcomes (ie, preterm birth, low birth weight, and small for gestational age). METHODS: We retrospectively examined 141 pregnancies in women with ulcerative colitis at 2 institutions. We categorized the patients into 3 subgroups by their preconception CFREM period (≥3 months, >0 to <3 months, and non-CFREM). We also investigated disease activity during pregnancy and postpartum and adverse pregnancy outcomes in each group. RESULTS: During pregnancy, the rate of active disease was significantly lower in the ≥3 months and >0 to <3 months CFREM groups compared with that in the non-CFREM group (P < .001 and P = .0257, respectively). Postpartum, the rate of active disease was significantly lower in the ≥3 months CFREM group compared with that in the non-CFREM group (P = .0087). The preconception CFREM period of ≥3 months was an independent inhibitory factor for active disease during pregnancy and postpartum (adjusted odds ratio, 0.15; P = .0035; and adjusted odds ratio, 0.33; P = .027, respectively). Adverse pregnancy outcomes were less common in the >3 months CFREM group compared with those in the other groups, but this difference was not significant. CONCLUSIONS: A preconception CFREM period of more than 3 months may be appropriate for better maternal and adverse pregnancy outcomes, as recommended in consensus statements.

In women with ulcerative colitis, a preconception corticosteroid-free remission period for at least 3 months may be appropriate. This period could reduce disease activity during pregnancy and postpartum and reduce the incidence of adverse pregnancy outcomes.

Clinical features and oncological outcomes of intestinal cancers associated with ulcerative colitis and Crohn's disease.

BACKGROUND: Patients with longstanding inflammatory bowel disease are at high risk of developing intestinal cancers. In this study, we aimed to elucidate the differences between intestinal cancers associated with ulcerative colitis and Crohn's disease. METHODS: Intestinal cancers in ulcerative colitis and Crohn's disease patients treated between 1983 and 2020 at 43 Japanese institutions were retrospectively analyzed.. RESULTS: A total of 1505 intestinal cancers in 1189 ulcerative colitis and 316 Crohn's disease patients were studied. Almost all of ulcerative colitis-associated cancers (99%) were in the colon and rectum, whereas half of Crohn's disease-associated cancers (44%) were in the anus, with 11% in the small intestine. Ulcerative colitis-associated cancers were diagnosed more frequently by surveillance (67% vs. 25%, P < 0.0001) and at earlier stages (stages 0-1, 71% vs. 27%, P < 0.0001) compared with Crohn's disease-associated cancers. Colorectal cancers associated with Crohn's disease showed a significantly worse 5-year overall survival rate than those associated with ulcerative colitis (stage 2, 76% vs. 89%, P = 0.01, stage 3, 18% vs. 68%, P = 0.0009, and stage 4, 0% vs. 13%, P = 0.04). Surveillance correlated with earlier diagnoses for ulcerative colitis- and Crohn's disease-associated intestinal cancers, whereas shorter intervals between endoscopic examinations correlated with an earlier cancer diagnosis in ulcerative colitis patients but not in Crohn's disease patients. CONCLUSIONS: The clinical and oncological features of ulcerative colitis- and Crohn's disease-associated cancers were very different. Crohn's disease-associated cancers were diagnosed at more advanced stages and were detected less frequently by surveillance. Additionally, they showed a significantly poorer prognosis.

Fulminant Amebic Enteritis in the Perinatal Period.

Pregnancy is a known risk factor for amebic enteritis, which develops into potentially fatal fulminant amebic enteritis in some cases. We describe a case of a 27-year-old non-immunosuppressed pregnant woman with fulminant amebic enteritis complicated with cytomegalovirus enteritis. She improved with intensive care and intravenous metronidazole and ganciclovir but eventually required subtotal colectomy for intestinal stenosis. It is difficult to diagnose amebic enteritis, especially in a non-endemic area. Amebic enteritis must be considered as a differential diagnosis for refractory diarrhea with bloody stools in women in the perinatal period, even those without immunosuppression.

[Surgical ulcerative colitis complicated by multiple lung abscesses secondary to septic pulmonary embolism after multidrug immunosuppressive therapies].

This is a case implying a serious infectious complication risk during intensive severe ulcerative colitis treatment. A 26-year-old man developed diarrhea and bloody stool who was diagnosed with ulcerative colitis in 2018. He was managed with 5-aminosalicylic acid, but intolerance reaction resulted in discontinuation of treatment. He relapsed with severe abdominal pain and bloody stools in February 2019. He was referred to our department for intensive therapy. He had been treated with steroids, tacrolimus, granulocyte and monocyte apheresis, infliximab or tofacitinib, which temporarily improved his clinical symptoms. However, his medical condition could not be controlled. Hand-assisted laparoscopic subtotal colectomy was then performed in October 2019. He developed intermittent fever on postoperative day 3. Enhanced computed tomography (CT) revealed multiple deep vein thromboses and pulmonary embolism. Antibiotics and anticoagulation therapy were initiated, but postoperative day 13 CT showed multiple pulmonary cavities containing fluids and air, which were diagnosed as pulmonary abscess. His intermittent fever was over 38.0°C. Severe cough and hemoptysis lasted 3 weeks, the clinical symptoms and laboratory data then gradually improved after the fourth week.

Inflammatory bowel disease-specific findings are common morphological changes in the ileal pouch with ulcerative colitis.

Why inflammation is common in ileal pouches with ulcerative colitis (UC) is unclear. We therefore clarified the morphological changes in pouches and afferent limbs (AL) of patients with UC and explored the relationship between these findings. We evaluated the morphological findings (histological and endoscopic inflammation as the Pouchitis Disease Activity Index [PDAI] histology subscore [hPDAI] and endoscopy subscore [ePDAI], inflammatory bowel disease [IBD]-specific findings using the IBD score [SIBD], colonic metaplasia using the colonic metaplasia score [CMS], and goblet cell [GC] ratio) in the pouch and AL of patients with UC. A total of 261 pouchoscopies were analyzed. The pouch body had a higher hPDAI (p < 0.001), SIBD (p < 0.001), CMS (p < 0.001), GC ratio (p < 0.001), and ePDAI (p < 0.001) than the AL. The hPDAI was correlated with the SIBD (Spearman's coefficient r = 0.538; p < 0.001), CMS (r = 0.687; p < 0.001), and the ePDAI (r = 0.552; p < 0.001), but not with GC ratio (r = 0.175; p < 0.001) or the pouch usage duration (r = -0.057; p = 0.107). The incidence of histological inflammation was higher in specimens showing basal plasmacytosis with severe mononuclear cell infiltration (BP) than in those without BP (odds ratio [OR] 6.790, p < 0.001), BP was commonly found with crypt hyperplasia (OR 3.414, p < 0.001) and the crypt length correlated with neutrophil infiltration (r = 0.469; p < 0.001). Histological inflammation, colonic metaplasia, the GC ratio, endoscopic inflammation, and IBD-specific findings were commonly present in the pouch than in the AL. Histological inflammation occurs with IBD-specific findings and colonic metaplasia, and these signify endoscopic inflammation.

Progression of ulcerative colitis following diversion colitis.

Diversion colitis and ulcerative colitis (UC) can be caused by different mechanisms; however, several case reports have described the development of typical UC following diversion colitis. A 63-year-old man underwent Hartmann's operation following a diagnosis of perforation of a sigmoid colon diverticulum and peritonitis. Stoma closure was performed 4 months later, and the portion of the sigmoid colon with the diverticulum was unintentionally left as a blind end. Following stoma closure, hematochezia worsened, and he was diagnosed as having developed diversion colitis only in the blind sigmoid colon. Intermittent use of topical mesalazine enemas controlled the bowel symptoms; however, 4 years after the stoma closure, bloody stools were observed again. Colonoscopy revealed coarse and friable granular mucosa with adherent mucopurulent exudate in the rectum, and mucosal erythematous edema with adherent mucopurulent exudate in the blind sigmoid colon. The histological findings indicated basal plasmacytosis, and goblet cell depletion and cryptitis in the lamina propria, which is characteristic of UC. To the best of our knowledge, this is the fourth description of a patient who developed UC following diversion colitis. Local inflammation may have triggered the development of UC through hematogenous or lymphogenous circulation of lymphocytes or autoantibodies.