The ileal fungal microbiota is altered in Crohn's disease and is associated with the disease course.

Introduction: Fungal microbiota's involvement in the pathogenesis of Crohn's disease (CD) is incompletely understood. The terminal ileum is a predilection site both for primary involvement and recurrences of CD. We, therefore, assessed the mucosa-associated mycobiota in the inflamed and non-inflamed ileum in patients with CD. Methods: The mucosa-associated mycobiota was assessed by ITS2 sequencing in a total of 168 biopsies sampled 5 and 15 cm proximal of the ileocecal valve or ileocolic anastomosis in 44 CD patients and 40 healthy controls (HC). CD patients with terminal ileitis, with endoscopic inflammation at 5 cm and normal mucosa at 15 cm and no history of upper CD involvement, were analyzed separately. The need for additional CD treatment the year following biopsy collection was recorded. Results: CD patients had reduced mycobiota evenness, increased Basidiomycota/Ascomycota ratio, and reduced abundance of Chytridiomycota compared to HC. The mycobiota of CD patients were characterized by an expansion of Malassezia and a depletion of Saccharomyces, along with increased abundances of Candida albicans and Malassezia restricta. Malassezia was associated with the need for treatment escalation during follow-up. Current anti-TNF treatment was associated with lower abundances of Basidiomycota. The alpha diversity of the inflamed and proximal non-inflamed mucosa within the same patients was similar. However, the inflamed mucosa had a more dysbiotic composition with increased abundances of Candida sake and reduced abundances of Exophiala equina and Debaryomyces hansenii. Conclusions: The ileal mucosa-associated mycobiota in CD patients is altered compared to HC. The mycobiota in the inflamed and proximal non-inflamed ileum within the same patients harbor structural differences which may play a role in the CD pathogenesis. Increased abundance of Malassezia was associated with an unfavorable disease course.

Factors associated with the persistence of oral 5-aminosalicylic acid monotherapy in ulcerative colitis: a nationwide Norwegian cohort study.

BACKGROUND: Oral 5-aminosalicylic acid (5-ASA) is the mainstay treatment of ulcerative colitis (UC) and therapy with oral 5-ASA is associated with beneficial outcomes. We have examined factors associated with the persistence of oral 5-ASA treatment in a national cohort of UC patients. METHODS: Patients with newly diagnosed UC from 2010 to 2014 using oral 5-ASA monotherapy were identified by combining data from the Norwegian Patient Registry and the Norwegian Prescription Database. The median follow-up time was 1029 days. Drug persistence was defined as duration of oral 5-ASA preparation as monotherapy. Non-persistence of a oral 5-ASA preparation as monotherapy was defined as stopping oral 5-ASA, initiation of any further anti-inflammatory treatment including a course of glucocorticoids and a change to another oral 5-ASA preparation. Drug persistence was analyzed using the Kaplan-Meier method and influence of covariates on drug persistence was analyzed with the Cox proportional hazard model. RESULTS: A total of 3421 patients were identified. The overall median 5-ASA drug persistence was 179 days. In univariate analyses, persistence was associated with preparation type and high-dose treatment, while oral glucocorticoid use or hospitalization around the start of oral 5-ASA were associated with shorter 5-ASA persistence. In multivariate analyses, oral glucocorticoids [HR 1.67 (1.54-1.80), p < 0.005] and hospitalization around start of 5-ASA [HR 1.23 (1.14-1.34), p < 0.005] were associated with non-persistence, whereas high dose (⩾3 g/day) 5-ASA was associated with longer persistence [HR 0.68 (0.65-0.71), p < 0.005]. CONCLUSION: High-dose treatment with oral 5-ASA was associated with longer persistence of oral 5-ASA monotherapy, whereas the presence of factors indicating more severe disease around initiation of 5-ASA monotherapy was associated with a shorter persistence.

Bacterial Mucosa-associated Microbiome in Inflamed and Proximal Noninflamed Ileum of Patients With Crohn's Disease.

BACKGROUND: Microbiota is most likely essential in the pathogenesis of Crohn's disease (CD). Fecal diversion after ileocecal resection (ICR) protects against CD recurrence, whereas infusion of fecal content triggers inflammation. After ICR, the majority of patients experience endoscopic recurrence in the neoterminal ileum, and the ileal microbiome is of particular interest. We have assessed the mucosa-associated microbiome in the inflamed and noninflamed ileum in patients with CD. METHODS: Mucosa-associated microbiome was assessed by 16S rRNA sequencing of biopsies sampled 5 and 15 cm orally of the ileocecal valve or ileocolic anastomosis. RESULTS: Fifty-one CD patients and forty healthy controls (HCs) were included in the study. Twenty CD patients had terminal ileitis, with endoscopic inflammation at 5 cm, normal mucosa at 15 cm, and no history of upper CD involvement. Crohn's disease patients (n = 51) had lower alpha diversity and separated clearly from HC on beta diversity plots. Twenty-three bacterial taxa were differentially represented in CD patients vs HC; among these, Tyzzerella 4 was profoundly overrepresented in CD. The microbiome in the inflamed and proximal noninflamed ileal mucosa did not differ according to alpha diversity or beta diversity. Additionally, no bacterial taxa were differentially represented. CONCLUSIONS: The microbiome is similar in the inflamed and proximal noninflamed ileal mucosa within the same patients. Our results support the concept of CD-specific microbiota alterations and demonstrate that neither ileal sublocation nor endoscopic inflammation influence the mucosa-associated microbiome.

Mucosal 5-aminosalicylic acid concentration, drug formulation and mucosal microbiome in patients with quiescent ulcerative colitis.

BACKGROUND: 5-aminosalicylic acid (5-ASA) is the first-line therapy for ulcerative colitis (UC). 5-ASA acts locally in the colonic mucosa by numerous proposed mechanisms, and is metabolised by N-acetyltransferase (NAT). Large variations in mucosal 5-ASA concentrations have been reported, but the underlying mechanisms are not understood. AIM: To study the relationship between 5-ASA concentration, 5-ASA formulation, NAT genotype and bacterial microbiome in patients with UC. METHODS: Patients with quiescent UC, using monotherapy of Mezavant (n = 18), Asacol (n = 14) or Pentasa (n = 10), 4.0-4.8 g/day were included. 5-ASA was measured in colonic mucosal biopsies and serum by ultra-high performance liquid chromatography. NAT genotypes were determined by Sanger sequencing. Bacterial microbiome was sequenced from faeces and mucosa by 16S rRNA sequencing using Illumina Miseq. RESULTS: Mezavant provided the highest mucosal 5-ASA levels (geometric mean 2.39 ng/mg), followed by Asacol (1.60 ng/mg, 33% lower, P = 0.50) and Pentasa (0.57 ng/mg, 76% lower, P = 0.033). Mucosal 5-ASA concentration was not associated with NAT genotype, but serum 5-ASA concentration and NAT1 genotype was associated (P = 0.044). Mucosal 5-ASA concentration was positively associated with mucosal bacterial diversity (P = 0.0005) and bacterial composition. High mucosal 5-ASA concentration was related to reduced abundance of pathogenic bacteria such as Proteobacteria, and increased abundance of several favourable bacteria such as Faecalibacterium. CONCLUSIONS: Mucosal 5-ASA concentration is positively associated with bacterial diversity and a mucosal bacterial composition that are perceived favourable in UC. Mezavant yielded higher mucosal 5-ASA concentrations than Pentasa. 5-ASA may have beneficial effects on the mucosal microbiome, and high concentrations possibly amend dysbiosis in UC.

Is there a role for routine colonoscopy in the follow-up after acute appendicitis?

BACKGROUND: Mechanical obstruction of the appendiceal lumen is proposed as a possible factor in the pathogenesis of acute appendicitis. Hence, patients over the age of 40 are often referred to a follow-up colonoscopy after admission for acute appendicitis. The use of CT scans question whether routine colonoscopy still has a place in follow-up for these patients. METHODS: All patients aged over 40 years with confirmed acute appendicitis admitted to St. Olav's Hospital in the period from 2010 to 2015 were included in this retrospective study. Findings and distribution of significant colorectal neoplasms (cancer and advanced adenomas) within three years after the admission were evaluated. RESULTS: Fifty-four (7.4%) of the 731 patients were found to have colonic neoplasms; 9 patients (1.2%) were found to have colorectal cancer of which 7 were located on the right side, 22 patients (3.0%) were found to have advanced adenomas and 23 patients (3.1%) were found to have non-advanced adenomas. The sensitivity and specificity for CT to discover cancer was 0.25 and 0.97, respectively. A total of 316 patients (43.2%) had colonoscopy within three years after admission. CONCLUSION: There may be an increased risk of colorectal neoplasms in patients over the age of 40 admitted with acute appendicitis. There seems to be an increased proportion of right-sided cancer relatively to other colonic locations. The sensitivity for CT scans to discover colorectal cancer in this group is low. Further studies are needed to decide whether routine colonoscopy is indicated after acute appendicitis in patients over 40 years.

5-Aminosalicylic acid, a specific drug for ulcerative colitis.

OBJECTIVE: The etiology of the inflammatory bowel diseases is unknown, although genetic factors play a role, and tobacco smoking has opposite effect on the two entities. Inflammation is central in the pathogenesis, and treatment is aiming to suppress it. The active part of salazopyrin, the oldest drug in use in the treatment of ulcerative colitis, is 5-aminosalicylic acid (5-ASA). In the present paper, we wanted to discuss the etiology and pathogenesis of ulcerative colitis in relation to the beneficial effects of 5-ASA and particularly whether this compound has a specific effect on ulcerative colitis. METHODS/RESULTS: 5-ASA seems to have a selective positive effect on ulcerative colitis in inducing remission, preventing relapse and possibly reducing the risk of cancer. In contrast to other agents used in the treatment of ulcerative colitis, 5-ASA does not have any known anti-inflammatory effect on other organs or other colonic inflammatory diseases like diverticulitis. Moreover, the effect on experimental colitis in rodents is not convincing. CONCLUSION: 5-ASA seems to have a specific effect on the inflammation in ulcerative colitis. Research on the mechanism of its action may give information on the etiology of ulcerative colitis. 5-ASA is a first-line treatment that should be given once daily in high doses and for long term to reduce the possibility of recurrence and risk of colonic cancer. Side effects with 5-ASA are rare, and every patient with ulcerative colitis who tolerate this drug, should be treated with 5-ASA.

Cytomegalovirus infection and postoperative complications in patients with ulcerative colitis undergoing colectomy.

BACKGROUND: Ulcerative colitis (UC) can be complicated by reactivation of cytomegalovirus (CMV). CMV reactivation may change the course of UC and may require antiviral treatment. Some risk factors of CMV reactivation have previously been identified, whereas the association between CMV reactivation and postoperative complications has not been examined systematically. METHODS: Patients with UC operated with colectomy due to active UC were studied (n = 77). Patient and disease characteristics, as well as postoperative complications were recorded and CMV was detected by immunohistochemical examination of multiple sections from the colectomy specimen. RESULTS: CMV was found in nine (11.7%) colectomy specimens. CMV-positive patients received significantly higher doses of corticosteroids at colectomy than CMV-negative patients (61.1 ± 23 vs 32.5 ± 32 mg/day, p = 0.01). CMV-positive patients were also older, had a higher risk of severe complications, higher American Society of Anesthesiologists (ASA) score, longer preoperative stay, and a higher rate of acute surgery. Complications occurred in 30 (39%) patients after surgery, 8(10.4%) of whom were serious. Two CMV-positive patients (2.6%) died in-hospital after the colectomy. High ASA score was associated with the occurrence of serious complications. CONCLUSION: A relatively small proportion of patients with UC operated by colectomy were CMV positive. CMV positivity was associated with old age, high dose of corticosteroids at operation, high ASA score, acute surgery, and severe postoperative complications. Patients with such characteristics may be at risk of CMV infection and may require special management.

Whole genome gene expression meta-analysis of inflammatory bowel disease colon mucosa demonstrates lack of major differences between Crohn's disease and ulcerative colitis.

BACKGROUND: In inflammatory bowel disease (IBD), genetic susceptibility together with environmental factors disturbs gut homeostasis producing chronic inflammation. The two main IBD subtypes are Ulcerative colitis (UC) and Crohn's disease (CD). We present the to-date largest microarray gene expression study on IBD encompassing both inflamed and un-inflamed colonic tissue. A meta-analysis including all available, comparable data was used to explore important aspects of IBD inflammation, thereby validating consistent gene expression patterns. METHODS: Colon pinch biopsies from IBD patients were analysed using Illumina whole genome gene expression technology. Differential expression (DE) was identified using LIMMA linear model in the R statistical computing environment. Results were enriched for gene ontology (GO) categories. Sets of genes encoding antimicrobial proteins (AMP) and proteins involved in T helper (Th) cell differentiation were used in the interpretation of the results. All available data sets were analysed using the same methods, and results were compared on a global and focused level as t-scores. RESULTS: Gene expression in inflamed mucosa from UC and CD are remarkably similar. The meta-analysis confirmed this. The patterns of AMP and Th cell-related gene expression were also very similar, except for IL23A which was consistently higher expressed in UC than in CD. Un-inflamed tissue from patients demonstrated minimal differences from healthy controls. CONCLUSIONS: There is no difference in the Th subgroup involvement between UC and CD. Th1/Th17 related expression, with little Th2 differentiation, dominated both diseases. The different IL23A expression between UC and CD suggests an IBD subtype specific role. AMPs, previously little studied, are strongly overexpressed in IBD. The presented meta-analysis provides a sound background for further research on IBD pathobiology.

[Use of TNFalpha antibodies in treatment of inflammatory bowel disease]. / Bruk av TNF-alpha-antistoff ved inflammatorisk tarmsykdom.

BACKGROUND: TNFalpha-antibodies have been used increasingly in treatment of inflammatory bowel disease (IBD) during the last years. This article provides an overview of indications, contraindications, efficacy, and side effects of this so-called biological treatment of IBD. MATERIAL AND METHODS: Based on the clinical experience of the authors, literature was selected through a non-systematic search in PubMed. RESULTS: TNFalpha-antibodies have a documented initial effect in 60-70 % of patients with moderate to severe luminal and/or fistulising IBD. Approximately 30 % of patients achieve remission after a relatively short treatment period. However, the effect seems to decrease during long-term treatment. It is still unsettled whether these drugs prevent colectomy in ulcerative colitis. The treatment seems to increase the risk of serious infections and there are also some indications of an increased risk of malignancy. Combination therapy with azathioprin is common and probably increases both the effect and the risk of side effects. INTERPRETATION: TNFalpha-antibodies have become an important part of the treatment for moderate to severe IBD, but the effect decreases during long-term treatment and has to be evaluated in light of potential side effects. Further long-term studies are necessary.