Indeterminate Colitis - Update on Treatment Options

Ouch, my pouch! a clinician's guide to pouchitis

Pouchitis is defined as inflammation of the ileal pouch created during a restorative proctocolectomy with ileal pouch-anal anastomosis. Although the incidence of this inflammatory condition is high, the exact etiology often remains unclear and the management challenging. In this review, we summarize the clinical presentation, pathogenesis, diagnosis, and management of this common complication.

Exploring potential biomarkers and therapeutic targets in inflammatory bowel disease: insights from a mega-analysis approach

Background

Understanding the molecular pathogenesis of inflammatory bowel disease (IBD) has led to the discovery of new therapeutic targets that are more specific and effective. Our aim was to explore the molecular pathways and genes involved in IBD pathogenesis and to identify new therapeutic targets and novel biomarkers that can aid in the diagnosis of the disease.

Methods

To obtain the largest possible number of samples and analyze them comprehensively, we used a mega-analysis approach. This involved reprocessing raw data from multiple studies and analyzing them using bioinformatic and machine learning techniques.

Results

We analyzed a total of 697 intestinal biopsies of Ulcerative Colitis (n = 386), Crohn's disease (n = 183) and non-IBD controls (n = 128). A machine learning analysis detected 34 genes whose collective expression effectively distinguishes inflamed biopsies of IBD patients from non-IBD control samples. Most of these genes were upregulated in IBD. Notably, among these genes, three novel lncRNAs have emerged as potential contributors to IBD development: ENSG00000285744, ENSG00000287626, and MIR4435-2HG. Furthermore, by examining the expression of 29 genes, among the 34, in blood samples from IBD patients, we detected a significant upregulation of 12 genes (p-value < 0.01), underscoring their potential utility as non-invasive diagnostic biomarkers. Finally, by utilizing the CMap library, we discovered potential compounds that should be explored in future studies for their therapeutic efficacy in IBD treatment.

Conclusion

Our findings contribute to the understanding of IBD pathogenesis, suggest novel biomarkers for IBD diagnosis and offer new prospects for therapeutic intervention.

Reclassification of Inflammatory Bowel Disease Type Unclassified by Small Bowel Capsule Endoscopy

Background and Objectives: Ulcerative colitis (UC) and Crohn's disease (CD) are idiopathic inflammatory bowel diseases (IBDs) without a unique, gold standard diagnostic test. UC and Crohn's colitis are impossible to distinguish in approximately 10% of cases. The term IBD type unclassified (IBD-U) is recommended for cases of chronic colitis showing overlapping endoscopic, radiological, and biopsy histological features between UC and CD, while indetermined colitis is reserved for colectomy specimens. Our aim was to assess the role of small-bowel capsule endoscopy (SBCE) in the diagnostic work-up of IBD-U. Materials and Methods: We retrospectively studied the cases of IBD-U explored by SBCE in a tertiary referral gastroenterology center. Patients were investigated using SBCE after contraindications were excluded. Diagnostic criteria for small bowel CD consisted in more than three ulcerations, irregular ulcers, or stenosis, and the Lewis score was used for the quantification of inflammation. The immediate impact of reclassification and outcome data was recorded over a follow-up period of more than one year. Results: Twenty-eight patients with IBD-U were examined using SBCE. Nine patients had small bowel lesions that met the diagnostic criteria for CD, resulting in a reclassification rate of 32.1%. In five of these cases, the treatment was subsequently changed. In the remaining nineteen examinations, no significant findings were observed. There were no complications associated with SBCE. Median follow-up time was 32.5 months (range 12-60). During follow-up, twelve patients were classified as having UC, and seven remained as having an unclassified type; one case of colectomy, for medically refractory UC, was recorded. Conclusions: SBCE is a useful safe tool in the work-up of IBD-U, allowing reclassification in about one third of cases, with subsequent treatment modifications. SBCE may provide a definite diagnosis, enhance the comprehension of the disease's progression, and optimize the short- and long-term management strategy.

A nationwide study of patients hospitalized with indeterminate colitis: a comparison with Crohn's disease and ulcerative colitis

PURPOSE

Indeterminate colitis (IC) is subtype of colonic inflammatory bowel disease (IBD) that has features of both Crohn's disease (CD) and ulcerative colitis (UC). There have also been no studies to date examining patients hospitalized with IC in the United States (US).

METHODS

We examined the demographic and clinical characteristics of patients admitted with IC and compared them with patients admitted with CD and UC. We also analyzed trends in cost and length of stay (LOS).

RESULTS

Patients admitted with IC tended to be female (58%), Caucasian (72%), and younger [39 (SD: 23) years]. Patients with IC underwent lower endoscopy at higher rates (26%; CD: p < 0.001, UC: p = 0.08) but bowel surgery at lower rates compared to those with CD (11% vs. 16%; p = 0.04). Patients with IC were found to have a higher rate of bowel obstruction (4% vs. 0.7%, p = 0.004) than those with UC, but lower rates of abscess and obstruction compared to patients with CD (p < 0.001). When the analysis was confined to patients who underwent bowel surgery, IC patients still demonstrated higher rates of lower endoscopy (p = 0.03) but lower rates of abscess compared to CD patients (p = 0.049). Costs increased significantly over time for CD- and UC-related hospitalizations, but not for admissions related to IC.

CONCLUSION

This is the first nationwide US study illustrating the demographics and clinical characteristics of patients hospitalized with IC. We conclude that IC has notable differences in hospitalization characteristics compared to the main two IBD subtypes.

Systematic Review and Meta-analysis of Peripheral Blood DNA Methylation Studies in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Over the past decade, the DNA methylome has been increasingly studied in peripheral blood of inflammatory bowel disease [IBD] patients. However, a comprehensive summary and meta-analysis of peripheral blood leukocyte [PBL] DNA methylation studies has thus far not been conducted. Here, we systematically reviewed all available literature up to February 2022 and summarized the observations by means of meta-analysis.

METHODS

We conducted a systematic search and critical appraisal of IBD-associated DNA methylation studies in PBL using the biomarker-based cross-sectional studies [BIOCROSS] tool. Subsequently, we performed meta-analyses on the summary statistics obtained from epigenome-wide association studies [EWAS] that included patients with Crohn's disease [CD], ulcerative colitis [UC] and/or healthy controls [HC].

RESULTS

Altogether, we included 15 studies for systematic review. Critical appraisal revealed large methodological and outcome heterogeneity between studies. Summary statistics were obtained from four studies based on a cumulative 552 samples [177 CD, 132 UC and 243 HC]. Consistent differential methylation was identified for 256 differentially methylated probes [DMPs; Bonferroni-adjusted p ≤ 0.05] when comparing CD with HC and 103 when comparing UC with HC. Comparing IBD [CD + UC] with HC resulted in 224 DMPs. Importantly, several of the previously identified DMPs, such as VMP1/TMEM49/MIR21 and RPS6KA2, were consistently differentially methylated across all studies.

CONCLUSION

Methodological homogenization of IBD epigenetic studies is needed to allow for easier aggregation and independent validation. Nonetheless, we were able to confirm previous observations. Our results can serve as the basis for future IBD epigenetic biomarker research in PBL.

Atherosclerotic Cardiovascular Disease in Inflammatory Bowel Disease: The Role of Chronic Inflammation and Platelet Aggregation

Background and Objectives: Atherosclerosis is one of inflammatory bowel disease’s most significant cardiovascular manifestations. This research aimed to examine the relationship between biochemical, haemostatic, and immune parameters of atherosclerosis and ulcerative colitis patients and its relationship to platelet aggregation. Materials and Methods: A clinical, observational cross-sectional study was performed, during which the tested parameters were compared in the experimental and control groups. The patients were divided into four groups. The first group had 25 patients who had ulcerative colitis and atherosclerosis. The second group included 39 patients with ulcerative colitis without atherosclerosis. The third group comprised 31 patients suffering from atherosclerosis without ulcerative colitis, and the fourth group comprised 25 healthy subjects. Results: In our study, we registered statistically higher levels of inflammatory markers like SE, CRP, Le, fecal calprotectin, TNF-α, and IL-6, as well as the higher value of thrombocytes and thrombocyte aggregation in the group of patients with ulcerative colitis compared to the control group. Lower levels of total cholesterol and LDL were also recorded in patients with ulcerative colitis and atherosclerosis and ulcerative colitis without atherosclerosis compared to healthy control. Triglyceride and remnant cholesterol were higher in patients with ulcerative colitis and atherosclerosis when compared to patients with ulcerative colitis and healthy control but lower than in patients with atherosclerosis only. Conclusions: Several inflammatory markers and platelet aggregation could be good discrimination markers for subjects with ulcerative colitis with the highest risk of atherosclerosis.

[Ileal pouch after restorative coloproctectomy]

The continuous development of pouch surgery has enabled continence-preserving treatment after coloproctectomy. The ileoanal J‑pouch is nowadays the standard reconstruction after restorative coloproctectomy with excellent functional long-term results. Taking the relative contraindications and a suitable patient selection into consideration, pouch placement can be indicated not only for ulcerative colitis and familial adenomatous polyposis, but also for patients with nonfistular Crohn's disease. Due to a high treatment density with immunosuppressants, the surgical treatment regimen should be subdivided into a multistage procedure, whereby according to current data a modified two-stage procedure should be favored.

Extracellular Vesicles: The Next Generation Theranostic Nanomedicine for Inflammatory Bowel Disease

The recent rapid development in the field of extracellular vesicles (EVs) based nanotechnology has provided unprecedented opportunities for nanomedicine platforms. As natural nanocarriers, EVs such as exosomes, exosome-like nanoparticles and outer membrane vesicles (OMVs), have unique structure/composition/morphology characteristics, and show excellent physical and chemical/biochemical properties, making them a new generation of theranostic nanomedicine. Here, we reviewed the characteristics of EVs from the perspective of their formation and biological function in inflammatory bowel disease (IBD). Moreover, EVs can crucially participate in the interaction and communication of intestinal epithelial cells (IECs)-immune cells-gut microbiota to regulate immune response, intestinal inflammation and intestinal homeostasis. Interestingly, based on current representative examples in the field of exosomes and exosome-like nanoparticles for IBD treatment, it is shown that plant, milk, and cells-derived exosomes and exosome-like nanoparticles can exert a therapeutic effect through their components, such as proteins, nucleic acid, and lipids. Moreover, several drug loading methods and target modification of exosomes are used to improve their therapeutic capability. We also discussed the application of exosomes and exosome-like nanoparticles in the treatment of IBD. In this review, we aim to better and more clearly clarify the underlying mechanisms of the EVs in the pathogenesis of IBD, and provide directions of exosomes and exosome-like nanoparticles mediated for IBD treatment.