Histopathology of IBD Colitis. A practical approach from the pathologists of the Italian Group for the study of the gastrointestinal tract (GIPAD)

Histological healing in IBD: Ready for prime time?

The main target of treatment in ulcerative colitis and Crohn's disease is to achieve a complete so-called mucosal healing. Various definitions of mucosal healing are available in literature, and the most recent ones include a combination of endoscopic and histological remission. However, the assessment of a complete histological remission is not always univocal. Absence of neutrophil infiltration in the lamina propria, together with neutrophil-mediated mucosal injuries in crypt and surface epithelium, is considered an important element to define histological remission. Although several histological scoring systems have been proposed to differentiate active vs quiescent disease and to evaluate the therapeutic efficacy, most of them are subjective and complex to employ in the daily diagnostic routine. For this reason, to simplify histologic scoring attempts have been made by introducing simplified scores, based on the evaluation of neutrophils and their mucosal localization. Artificial intelligence models are also being developed to standardize histological assessment of mucosal healing, and new biomarkers, such as claudin- 2, are emerging to simplify this latter aspect.

The importance of MUC6 immunohistochemistry staining in the histopathologic examination of Crohn's disease: can we enhance our diagnostic power?

Crohn's disease (CD) is a chronic inflammatory bowel disease characterized by transmural inflammation and histopathologic variability, making diagnosis challenging. Pseudopyloric metaplasia (PPM) is a key histological feature of chronicity in CD. However, its identification on hematoxylin & eosin (H&E)-stained slides is subject to interobserver variability. MUC6 immunohistochemistry (IHC) has been suggested as a useful marker for pyloric glands. This study aims to evaluate the diagnostic utility of MUC6 staining in detecting PPM and to assess interobserver agreement compared to H&E staining. In this retrospective study, 38 terminal ileum biopsies from CD patients were analyzed. H&E-stained and MUC6-stained slides were evaluated independently by four pathologists for the presence and gland count of PPM. Intraobserver and interobserver agreements were assessed using Intraclass Correlation Coefficient (ICC). The mean PPM count was significantly higher with MUC6 staining than by H&E alone. Intraobserver agreement between H&E and MUC6 staining was "moderate" (ICC = 0.577, 0.734, 0.738) for three pathologists and "poor" (ICC = 0.439) for one. Interobserver agreement was classified as "good" for H&E slides (ICC = 0.849) and "excellent" for MUC6-stained slides (ICC = 0.993). PPM is an important finding that is not specific for CD but indicates chronic mucosal damage in the gastrointestinal tract. In our study, MUC6 IHC staining in CD improved the detection of PPM and increased interobserver agreement in the detection of PPM. The increase in the number of detectable metaplastic glands in all observers demonstrates the potential of MUC6 staining as a reliable marker. MUC6 IHC may provide a more standardized and objective evaluation, reducing diagnostic variability.

Anti-inflammatory and immunomodulatory effects of Glycyrrhiza uralensis fisch. On ulcerative colitis in rats: Role of nucleotide-binding oligomerization domain 2/receptor-interacting protein 2/nuclear factor-kappa B signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

As a traditional Chinese herb, Glycyrrhiza uralensis Fisch. exhibits a range of pharmacological activities, including anti-inflammatory, immunomodulatory and antifibrotic, which suggests its therapeutic potential for inflammatory bowel disease, and related mechanisms need to be further clarified.

AIM OF THE STUDY

To evaluate in vivo anti-inflammatory effects of Glycyrrhiza uralensis Fisch. aqueous extract (GE) on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced acute experimental colitis rat model and its potential mechanisms.

MATERIALS AND METHODS

The protective effects of GE on IBD were evaluated in vivo using a TNBS and 75% ethanol-induced ulcerative colitis (UC) model. The evaluated clinical and anatomical indexes included body weight, colon length, disease activity index (DAI) score, Colonic Mucosal Damage Index (CMDI) score. The percentages of T, B lymphocytes, NK cells, and macrophages in the colon, spleen and peripheral blood were investigated by flow cytometry. Colon tissues were stained with Hematoxylin and Eosin (H&E) for histopathological examination. After using transcriptome sequencing to screen targeted genes, the expression of related genes was detected by Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR) and Western blot (WB).

RESULTS

The decrease of food intake, soft feces, and colon histopathological injury were observed in colitis rats, which were alleviated by GE, with the best therapeutic effect in the 100 mg/kg GE group. The average CMDI scores of colon in UC rats were decreased from 4.0 to 1.5. The percentages of CD161a+ NK cells, CD68+ total macrophages, CD68+/CD161a+ M1 type macrophages, CD3+ T lymphocytes, and CD45RA+ B lymphocytes were decreased in the spleen and colon. The transcriptomics analysis of colon showed that the results were mainly related to the TNF signaling pathway and NF-κB signaling pathway. The RT-qPCR and WB results determined that the upregulated expression of nucleotide-binding oligomerization domain 2 (NOD2), receptor-interacting protein 2 (RIP2), nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α) in the colon of the colitis rats were downregulated by GE treatment.

CONCLUSION

The research results indicate that GE can exert therapeutic effects on TNBS-induced UC in rats by alleviating cell injury and inflammatory responses, and its mechanisms may be related to the regulation of NOD2/RIP2/NF-κB signaling pathway.

Application of finite mixture models to explore subpopulations in Crohn's disease patients

BACKGROUND

Inflammatory bowel disease (IBD) commonly refers to ulcerative colitis (UC) and Crohn disease (CD), which are chronic inflammatory diseases of the gastrointestinal (GI) tract of unknown etiology. This study has been conducted to examine whether there are different components in the data, and if these components related to the treatment and the Inflammatory bowel disease (IBD) score at baseline.

METHODOLOGY

This is a clinical study which consisted of 291 subjects, who divided over four treatment arms and were measured during a seven-week period. The number of weeks in the period Week 0ne through Week seven was considered as the outcome of interest, as well treatment and IBD score at baseline were considered as predictors. Different statistical methods such as explanatory data analysis and finite mixture model were employed to explore the outcome of interest.

RESULTS

From the finite mixture model, two components were obtained. Most of the patients, 196(67.4%), were classified in the first component (P1). The deviance for single component of the mixture model corrected for the covariates was 1049.3 and that of the two components was 948.8. The effect of ibdsc0 was significant in both subpopulations with p-value = 0.0001 for subpopulation1, and p-value = 0.0422 for subpopulation2, and Exp (0.01) = 1.01 and exp(0.087) = 1.09 are the amounts by which the mean count (µ) is multiplied per unit change in the ibdsc0 for subpopulations 1 and 2, respectively.

CONCLUSIONS

The two components are not related to the treatment, and as a result, the treatment does not completely explain the presence of potential clusters in the outcome. Ibdsc0 partially explains the presence of potential clusters in the outcome.

Fructosyl-mangiferin ameliorates dextran sulfate sodium-induced colitis in mice via the STAT3/M1/Th17 axis

BACKGROUND

Inflammatory bowel disease (IBD), a chronic inflammatory condition categorized into ulcerative colitis (UC) and Crohn's disease (CD), affects a growing global patient population. Despite the prevalence, clinically there is a scarcity of effective therapeutic agents.

PURPOSE

This study investigated the therapeutic effects of fructosyl mangiferin (FM) on UC and elucidated its underlying mechanisms through in vivo and in vitro experiments.

METHODS

In vivo, a UC model of C57BL/6J mice was established via dextran sulfate sodium (DSS) induction, and the therapeutic effects were assessed through intragastric administration. In vitro, the murine macrophage cell line RAW264.7 was stimulated with lipopolysaccharide (LPS) to establish an M1 polarization model and introduced to explore the role of FM in immune cells. Molecular docking was further employed to investigate the specific molecular mechanisms of FM.

RESULTS

In vivo experimental findings indicate that FM, like mangiferin (M), preserves mucin secretion and the expression of occludin protein, and both significantly impede the progression of fibrosis associated with colitis. Additionally, FM effectively suppresses M1 macrophage polarization and exerts a pronounced inhibitory effect on the adaptive immune response, outperforming M in mitigating UC. In vitro results corroborate FM's inhibitory action on M1 polarization. Molecular docking studies identified FM as a potential signal transducer and activator of transcription 3 (STAT3) inhibitor, aligning with western blot analyses from both in vivo and in vitro experiments.

CONCLUSION

In conclusion, following fructosylation, FM exhibits remarkable anti-inflammatory and colonic protective effects. FM's ability to control the progression of UC offers a novel strategy for its potential treatment, warranting further investigation into its clinical application.

The development of artificial intelligence in the histological diagnosis of Inflammatory Bowel Disease (IBD-AI)

BACKGROUND

Inflammatory bowel disease (IBD) includes Crohn's Disease (CD) and Ulcerative Colitis (UC). Correct diagnosis requires the identification of precise morphological features such basal plasmacytosis. However, histopathological interpretation can be challenging, and it is subject to high variability.

AIM

The IBD-Artificial Intelligence (AI) project aims at the development of an AI-based evaluation system to support the diagnosis of IBD, semi-automatically quantifying basal plasmacytosis.

METHODS

A deep learning model was trained to detect and quantify plasma cells on a public dataset of 4981 annotated images. The model was then tested on an external validation cohort of 356 intestinal biopsies of CD, UC and healthy controls. AI diagnostic performance was calculated compared to human gold standard.

RESULTS

The system correctly found that CD and UC samples had a greater prevalence of basal plasma cells with mean number of PCs within ROIs of 38.22 (95 % CI: 31.73, 49.04) for CD, 55.16 (46.57, 65.93) for UC, and 17.25 (CI: 12.17, 27.05) for controls. Overall, OR=4.968 (CI: 1.835, 14.638) was found for IBD compared to normal mucosa (CD: +59 %; UC: +129 %). Additionally, as expected, UC samples were found to have more plasma cells in colon than CD cases.

CONCLUSION

Our model accurately replicated human assessment of basal plasmacytosis, underscoring the value of AI models as a potential aid IBD diagnosis.

Cross-sectional imaging of mimics of inflammatory bowel disease: not everything is Crohn's disease or ulcerative colitis

Acute and chronic bowel pathologies can often be mistaken for manifestations of inflammatory bowel disease (IBD), and there are many entities with imaging and clinical features that overlap with IBD, making diagnosis difficult. We describe multiple inflammatory, infectious, neoplastic, and vascular entities with imaging and clinical features that may mimic IBD, and highlight differentiating features to assist in diagnosis.

Artificial intelligence: A new tool in the pathologist's armamentarium for the diagnosis of IBD

Inflammatory bowel diseases (IBD) are classified into two entities, namely Crohn's disease (CD) and ulcerative colitis (UC), which differ in disease trajectories, genetics, epidemiological, clinical, endoscopic, and histopathological aspects. As no single golden standard modality for diagnosing IBD exists, the differential diagnosis among UC, CD, and non-IBD involves a multidisciplinary approach, considering professional groups that include gastroenterologists, endoscopists, radiologists, and pathologists. In this context, histological examination of endoscopic or surgical specimens plays a fundamental role. Nevertheless, in differentiating IBD from non-IBD colitis, the histopathological evaluation of the morphological lesions is limited by sampling and subjective human judgment, leading to potential diagnostic discrepancies. To overcome these limitations, artificial intelligence (AI) techniques are emerging to enable automated analysis of medical images with advantages in accuracy, precision, and speed of investigation, increasing interest in the histological analysis of gastrointestinal inflammation. This review aims to provide an overview of the most recent knowledge and advances in AI methods, summarizing its applications in the histopathological analysis of endoscopic biopsies from IBD patients, and discussing its strengths and limitations in daily clinical practice.

Prevalence of Metabolic Syndrome and Its Association with Cardiovascular Outcomes in Hospitalized Patients with Inflammatory Bowel Disease

Background: Patients with autoimmune diseases experience a higher burden of metabolic syndrome (MetS) and cardiovascular disease (CVD). There is a paucity of data regarding MetS in patients with inflammatory bowel disease (IBD) and its impact on CVD. In this retrospective study, we aimed to evaluate the prevalence of MetS components in IBD patients, as well as their association with acute coronary syndrome (ACS), heart failure and arrhythmias. Methods: After pooling 5 years of data from the National Inpatient Sample (NIS) Database (2016-2020), we compared traditional cardiovascular risk factors between IBD and non-IBD patients. We then investigated the association between MetS (represented by a calculated metabolic score (CMS) ranging from 0 to 4, based on the presence or absence of hypertension, obesity, dyslipidemia and type II diabetes) and CVD, separately for Crohn's disease (CD) and ulcerative colitis (UC) patients. Results: The prevalence of the different MetS components was found to be lower in IBD patients compared to non-IBD patients. Comparing CD (n = 806,875) and UC (n = 575,925) identified a higher prevalence of MetS components in UC. Higher CMS was positively associated with ACS and arrhythmias in both CD and UC. This association was evident in heart failure, with the odds ratio increasing from 2.601 for CMS = 1 to 6.290 for CMS = 4 in UC patients and from 2.622 to 5.709 in CD patients. Conclusions: Our study highlights the positive association between traditional components of MetS and CVD in IBD patients. Our findings suggest that chronic inflammation explains only partially the CVD burden in hospitalized IBD patients.

Establishment of an ulcerative colitis model using colon organoids derived from human induced pluripotent stem cells

The etiology of inflammatory bowel disease (IBD) is complex, with much room for a greater understanding and development of improved therapies. Therefore, establishing a reliable IBD model is crucial for future advancements. In this study, human induced pluripotent stem (iPS) cell-derived colon organoids (hiPSC-COs) were treated with a combination of tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), and interleukin (IL)-1β (3 cytokines [3CK]), known to be elevated in the serum of IBD patients. Inflammatory responses in stromal cells and damage to intestinal epithelial cells were observed in the 3CK-treated hiPSC-COs. Comparison of molecular signatures of 3CK-treated hiPSC-COs with those of ulcerative colitis (UC) patient's colon revealed that 3CK-treated hiPSC-COs resemble UC patient's colon. Furthermore, the elevated production of inflammatory cytokines observed in 3CK-treated hiPSC-COs was attenuated by treatment with tofacitinib. Our UC model will be an essential tool to understand its pathologic mechanisms and identify effective therapeutic approaches.

A Systematic Review and Metaanalysis to Examine the Utility of Histological Parameters Such as Mucosal Basal Plasmacytosis and Eosinophilia for Distinguishing Inflammatory Bowel Disease and Non-IBD-Type Colitis

Background and aim: Basic differentiation between an inflammatory bowel disease (IBD)-type colitis and a non-IBD type of colitis is the essential histological pre-requisite before further subclassifications are made. The combination of mucosal prominent eosinophilic cell infiltrate along with basal plasmacytosis is supposed to be a useful histological feature that can differentiate between IBD-type and non-IBD-type colitis. Hence, this systematic review and metaanalysis aimed to assess the reliability of mucosal basal plasmacytosis and eosinophilia for histological differentiation of IBD-type versus non-IBD-type colitis. Methods: We searched the PROSPERO, PubMed, Embase, and Scopus from January 1, 2000 to July 30, 2022 for all types of studies (prospective, cross-sectional, or retrospective studies) having histological features (including mucosal basal plasmacytosis, eosinophilia, and neutrophilic infiltration) in IBD and/or non-IBD colitis cases. Two reviewers extracted data, which were aggregated using random-effects models. Results: The 59 selected articles were evaluated for the predecided parameters. Both basal plasmacytosis and lamina propria plasmacytosis did not show any significant correlation between IBD-type and non-IBD-type colitis. The proportions for basal plasmacytosis with 95% CI were 0.50 (0.19-0.82) in IBD-type colitis and 0.46 (0.40-0.52) in non-IBD-type colitis, with a P value of .79. The proportion of lamina propria plasmacytosis with 95% CI was 0.67 (0.42-0.92) in IBD and 0.60 (0.35-0.85) in non-IBD-type colitis, with a P value being .7. Conclusions: This systematic review documented the dearth of published data on key histological features such as basal plasmacytosis and mucosal eosinophilia which are believed to differentiate between IBD-type and non-IBD-type colitis.

Gastrointestinal Manifestations of Sarcoidosis: A State-of-the-Art, Comprehensive Review of the Literature-Practical Clinical Insights and Many Unmet Needs on Diagnosis and Treatment

This comprehensive literature review explores the involvement of the gastrointestinal (GI) tract in sarcoidosis, a multisystem granulomatous disorder of unknown etiology. GI sarcoidosis presents a diagnostic and therapeutic challenge due to its rarity and nonspecific clinical manifestations, including overlap with other gastrointestinal diseases. We conducted a comprehensive screening of articles addressing the clinical features, diagnostic approaches, and treatment strategies for GI sarcoidosis. Our findings reveal that GI sarcoidosis can affect any part of the gastrointestinal tract, with the stomach and small intestine being the most involved. Clinical presentations range from asymptomatic cases to severe complications such as obstruction and perforation, with reflux being a common symptom. Diagnosis is often delayed due to the nonspecific nature of symptoms and the need for histopathological confirmation. Therapeutic approaches are poorly defined, typically involving corticosteroids as the mainstay of treatment. However, the long-term efficacy and safety of these treatments remain uncertain in this patient group, given the significant risks and complications associated with prolonged glucocorticoid therapy. There is a clear need to develop accurate diagnostic protocols to distinguish GI sarcoidosis from other conditions and to establish standardized therapeutic guidelines to optimize patient outcomes. Further research is essential to enhance our understanding and management of this complex condition.

Role of Extracellular Vesicles in Crohn's Patients on Adalimumab Who Received COVID-19 Vaccination

Crohn's disease (CD) is a type of inflammatory bowel disease (IBD) affecting the gastrointestinal tract that can also cause extra-intestinal complications. Following exposure to the mRNA vaccine BNT162b2 (Pfizer-BioNTech) encoding the SARS-CoV-2 Spike (S) protein, some patients experienced a lack of response to the biological drug Adalimumab and a recrudescence of the disease. In CD patients in progression, resistant to considered biological therapy, an abnormal increase in intestinal permeability was observed, more often with a modulated expression of different proteins such as Aquaporin 8 (AQP8) and in tight junctions (e.g., ZO-1, Claudin1, Claudin2, Occludin), especially during disease flares. The aim of this study is to investigate how the SARS-CoV-2 vaccine could interfere with IBD therapy and contribute to disease exacerbation. We investigated the role of the SARS-CoV-2 Spike protein, transported by extracellular vesicles (EVs), and the impact of various EVs components, namely, exosomes (EXOs) and microvesicles (MVs), in modulating the expression of molecules involved in the exacerbation of CD, which remains unknown.

Study of Inflammatory Bowel Disease in Patients Undergoing Colonoscopy at a Tertiary Center of Nepal

Introduction Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract that includes ulcerative colitis (UC) and Crohn's disease (CD). The incidence and prevalence of disease are on a rising trend. Increased case detection is related to better health awareness and improved availability of diagnostic services in the community. This article aims to calculate the incidence of IBD per 1,000 colonoscopies per year and to study the clinical and demographic characteristics of patients with IBD. Methodology It was a prospective observational study done at the National Academy of Medical Sciences, Bir Hospital, Kathmandu, Nepal, from March 2023 to February 2024. All the patients who underwent colonoscopy during the study period were assessed for possible diagnosis of IBD. The Incidence rate was calculated as new IBD cases per 1,000 colonoscopies per year. Demographic and clinical profiles of the patients were collected. Results  Among 1,248 patients who underwent colonoscopy during the study period, IBD was detected in 52 patients (4.16%). UC was diagnosed in 43 patients and the incidence rate of it was calculated to be 34.4 cases per 1,000 colonoscopies per year. Similarly, CD was diagnosed in nine patients with its incidence rate being 7.2 cases per 1,000 colonoscopies per year. Disease was predominantly seen in females (F:M ratio - 1.36:1). The mean age at diagnosis of IBD was 39.67 ± 14.53 years, with patients with CD being slightly younger than those with UC. The majority of patients with UC had pancolitis. The median time to diagnosis from symptom onset was three years (range: 6 months to 7 years) for CD and 10 months for patients with UC (range: 2 months to 5 years). The most common extra-intestinal manifestations were arthralgia (11, 21.15%) and arthritis (7, 13.46%). Traditional drugs like mesalamine, prednisolone, and azathioprine were commonly prescribed. Biologics were used only in two (3.84%) patients, including infliximab and adalimumab. Janus kinase inhibitor (tofacitinib) was used in three (5.76%) patients in cases of acute severe UC. Conclusions Due to the rising trend of awareness in health and availability of colonoscopy services in our country like Nepal, the incidence of IBD is seen to be quite high. UC was seen more commonly than CD, and females were predominantly involved. The majority of patients belonged to the young and middle-aged population. The majority of patients with UC had extensive colitis, while patients with CD had ileo-colonic disease with non-stricturing, non-penetrating phenotypes. Arthralgia and arthritis were the most common extra-intestinal manifestations. Conventional drugs like mesalamine, prednisolone, and immunomodulators such as azathioprine were mostly used. The use of biologics was fairly low. This study certainly contributes to the existing literature from Nepal regarding IBD.

The Role of Viruses in the Pathogenesis of Immune-Mediated Gastro-Intestinal Diseases

Immune-mediated gastrointestinal (GI) diseases, including achalasia, celiac disease, and inflammatory bowel diseases, pose significant challenges in diagnosis and management due to their complex etiology and diverse clinical manifestations. While genetic predispositions and environmental factors have been extensively studied in the context of these conditions, the role of viral infections and virome dysbiosis remains a subject of growing interest. This review aims to elucidate the involvement of viral infections in the pathogenesis of immune-mediated GI diseases, focusing on achalasia and celiac disease, as well as the virome dysbiosis in IBD. Recent evidence suggests that viral pathogens, ranging from common respiratory viruses to enteroviruses and herpesviruses, may trigger or exacerbate achalasia and celiac disease by disrupting immune homeostasis in the GI tract. Furthermore, alterations in the microbiota and, specifically, in the virome composition and viral-host interactions have been implicated in perpetuating chronic intestinal inflammation in IBD. By synthesizing current knowledge on viral contributions to immune-mediated GI diseases, this review aims to provide insights into the complex interplay between viral infections, host genetics, and virome dysbiosis, shedding light on novel therapeutic strategies aimed at mitigating the burden of these debilitating conditions on patients' health and quality of life.

Aged garlic therapeutic intervention targeting inflammatory pathways in pathogenesis of bowel disorders

Inflammatory bowel diseases (IBD), which include Crohn's disease and ulcerative colitis, manifest as a result of intricate interactions involving genetic predisposition, environmental factors, intestinal microbiota dynamics, and immune dysregulation, ultimately leading to persistent mucosal inflammation. Addressing this complex pathology requires a nuanced understanding to inform targeted therapeutic strategies. Consequently, our study explored the viability of Aged Garlic Extract (AGE) as an alternative therapeutic regimen for IBD management. Utilizing gas chromatography-mass spectrometry (GC-MS) and scanning electron microscopy (SEM), we characterized AGE, revealing distinctions from Fresh Garlic Extract (FGE), particularly the absence of allicin in AGE and accompanying structural alterations. In In-Vivo experiments employing an IBD rat model, AGE intervention exhibited remarkable antioxidant, antibacterial, and anti-inflammatory properties. Noteworthy outcomes included improved survival rates, mitigation of intestinal damage, restoration of gut microbial diversity, reinforcement of tight junctions, and reversal of mitochondrial dysfunction. Collectively, these effects contributed to the preservation of enterocyte integrity and the attenuation of inflammation. In conclusion, the unique chemical composition of AGE, coupled with its substantial influence on gut microbiota, antioxidant defenses, and inflammatory pathways, positions it as a promising adjunctive therapy for the management of IBD. These observations, synergistically considered with existing research, provide significant insights into the potential utility of AGE in addressing the intricate pathophysiology inherent to IBD. The potential strength of study and rationale of using AGE against IBD includes exploring alternative therapeutic regimens if conventional treatments are associated with side effects, identification of potential hotspots/pathways involved in disease progression and study can provide economically cheaper and naturally occurring alternative to patient community who are struggling to afford expensive medications. These promising findings underscore the necessity for additional investigations to ascertain the feasibility of clinical translation, thereby substantiating the potential therapeutic role of AGE in the management of IBD.

Eosinophils, Eosinophilic Gastrointestinal Diseases, and Inflammatory Bowel Disease: A Critical Review

BACKGROUND/OBJECTIVES

Inflammatory bowel disease (IBD) and eosinophilic gastrointestinal diseases (EGIDs) are complex, multifactorial chronic inflammatory disorders affecting the gastrointestinal tract. Their epidemiology, particularly for eosinophilic esophagitis (EoE), is increasing worldwide, with a rise in the co-diagnosis of IBD and EGIDs. Both disorders share common risk factors, such as early exposure to antibiotics or specific dietary habits. Moreover, from a molecular perspective, eosinophilic infiltration is crucial in the diagnosis of eosinophilic disorders, and it also plays a pivotal role in IBD histological diagnosis. Indeed, recent evidence highlights the significant role of eosinophils in the health of the intestinal mucosal barrier and as mediators between innate and acquired immunity, even indicating a potential role in IBD pathogenesis. This narrative review aims to summarize the current evidence regarding the common clinical and molecular aspects of EGIDs and IBD and the current state of knowledge regarding overlap conditions and their pathogenesis.

METHODS

Pubmed was searched until May 2023 to assess relevant studies describing the epidemiology, pathophysiology, and therapy of EGIDs in IBD.

RESULTS

The immune pathways and mechanisms underlying both EGIDs and IBD remain partially known. An improved understanding of the role of eosinophils in overlapping conditions could lead to enhanced diagnostic precision, the development of more effective future therapeutic strategies, and a more accurate prediction of patient response. Consequently, the identification of red flags indicative of an eosinophilic disorder in IBD patients is of paramount importance and must be evaluated on a case-by-case basis.

Histopathological characterization and grading of chronic enterocolitis in Sulawesi crested macaques (Macaca nigra)

Sulawesi crested macaques (Macaca nigra) (SCMs) are critically endangered and frequently suffer from chronic intestinal disease in captivity. Often, despite routine diagnostic investigations and confirmation of intestinal inflammation, an aetiology cannot be identified, leading to a non-specific categorization as chronic enterocolitis rather than an aetiological diagnosis. This study evaluates the histological features of gastrointestinal tissues from 23 SCMs, comparing animals with a clinical history suggestive of chronic enterocolitis (n = 14) with those without gastrointestinal clinical signs (n = 9). Tissues were graded according to the Nancy index (NI), a scoring system used in human medicine to evaluate disease activity in ulcerative colitis, a common form of human inflammatory bowel disease (IBD). Additionally, inflammatory cells in the colonic lamina propria were visually identified by type, counted and subsequently compared between diseased and control animals. Moderate to severe lymphoplasmacytic inflammation and structural changes were most common in the colons of affected SCMs, whereas histopathological changes were absent or mild in all examined small intestine (n = 17) and stomach (n = 11) tissues. The colonic NI had a significant positive correlation with clinical disease severity and 57% (n = 8) of animals with clinical signs had a NI grade of ≥2, consistent with moderate to severe, active IBD. Half of SCMs with recurrent rectal prolapse (n = 6) had a NI grade of 0, suggesting that intestinal inflammation is not always part of this condition's pathogenesis. The numbers of colonic lymphocytes, plasma cells, neutrophils, macrophages and total leucocytes were significantly higher in diseased animals. This study validated the use of the NI in SCMs, enabling a more standardized histopathological evaluation of the colon in this species.

Management of Crohn's disease in Taiwan: consensus guideline of the Taiwan Society of Inflammatory Bowel Disease updated in 2023

Crohn's disease (CD) is a chronic, fluctuating inflammatory condition that primarily affects the gastrointestinal tract. Although the incidence of CD in Taiwan is lower than that in Western countries, the severity of CD presentation appears to be similar between Asia and the West. This observation indicates the urgency for devising revised guidelines tailored to the unique reimbursement system, and patient requirements in Taiwan. The core objectives of these updated guidelines include the updated treatment choices and the integration of the treat-to-target strategy into CD management, promoting the achievement of deep remission to mitigate complications and enhance the overall quality of life. Given the diversity in disease prevalence, severity, insurance policies, and access to medical treatments in Taiwan, a customized approach is imperative for formulating these guidelines. Such tailored strategies ensure that international standards are not only adapted but also optimized to local contexts. Since the inception of its initial guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease (TSIBD) has acknowledged the importance of continuous revisions for incorporating new therapeutic options and evolving disease management practices. The latest update leverages international standards and recent research findings focused on practical implementation within the Taiwanese healthcare system.

Diagnostic Procedures for Inflammatory Bowel Disease: Laboratory, Endoscopy, Pathology, Imaging, and Beyond

Diagnosing inflammatory bowel disease (IBD) can often be challenging, and differentiating between Crohn's disease and ulcerative colitis can be particularly difficult. Diagnostic procedures for IBD include laboratory tests, endoscopy, pathological tests, and imaging tests. Serological and stool tests can be easily performed in an outpatient setting and provide critical diagnostic clues. Although endoscopy is an invasive procedure, it offers essential diagnostic information and allows for tissue biopsy and therapeutic procedures. Video capsule endoscopy and device-assisted enteroscopy are endoscopic procedures used to evaluate the small bowel. In addition to endoscopy, magnetic resonance imaging, computed tomography, and ultrasound (US) are valuable tools for small bowel assessment. Among these, US is noninvasive and easily utilized, making its use highly practical in daily clinical practice. Endoscopic biopsy aids in the diagnosis of IBD and is crucial for assessing the histological activity of the disease, facilitating a thorough evaluation of disease remission, and aiding in the development of treatment strategies. Recent advances in artificial intelligence hold promise for enhancing various aspects of IBD management, including diagnosis, monitoring, and precision medicine. This review compiles current procedures and promising future tools for the diagnosis of IBD, providing comprehensive insights.

Clostridioides difficile infection: history, epidemiology, risk factors, prevention, clinical manifestations, treatment, and future options

SUMMARYClostridioides difficile infection (CDI) is one of the major issues in nosocomial infections. This bacterium is constantly evolving and poses complex challenges for clinicians, often encountered in real-life scenarios. In the face of CDI, we are increasingly equipped with new therapeutic strategies, such as monoclonal antibodies and live biotherapeutic products, which need to be thoroughly understood to fully harness their benefits. Moreover, interesting options are currently under study for the future, including bacteriophages, vaccines, and antibiotic inhibitors. Surveillance and prevention strategies continue to play a pivotal role in limiting the spread of the infection. In this review, we aim to provide the reader with a comprehensive overview of epidemiological aspects, predisposing factors, clinical manifestations, diagnostic tools, and current and future prophylactic and therapeutic options for C. difficile infection.

Panaxynol improves crypt and mucosal architecture, suppresses colitis-enriched microbes, and alters the immune response to mitigate colitis

Ulcerative colitis (UC) is an idiopathic inflammatory disease of the large intestine, which impacts millions worldwide. Current interventions aimed at treating UC symptoms can have off-target effects, invoking the need for alternatives that may provide similar benefits with less unintended consequences. This study builds on our initial data, which showed that panaxynol-a novel, potent, bioavailable compound found in American ginseng-can suppress disease severity in murine colitis. Here we explore the underlying mechanisms by which panaxynol improves both chronic and acute murine colitis. Fourteen-week-old C57BL/6 female mice were either given three rounds of dextran sulfate sodium (DSS) in drinking water to induce chronic colitis or one round to induce acute colitis. Vehicle or panaxynol (2.5 mg/kg) was administered via oral gavage three times per week for the study duration. Consistent with our previous findings, panaxynol significantly (P < 0.05) improved the disease activity index and endoscopic scores in both models. Using the acute model to examine potential mechanisms, we show that panaxynol significantly (P < 0.05) reduced DSS-induced crypt distortion, goblet cell loss, and mucus loss in the colon. 16S Sequencing revealed panaxynol altered microbial composition to suppress colitis-enriched genera (i.e., Enterococcus, Eubacterium, and Ruminococcus). In addition, panaxynol significantly (P < 0.05) suppressed macrophages and induced regulatory T-cells in the colonic lamina propria. The beneficial effects of panaxynol on mucosal and crypt architecture, combined with its microbial and immune-mediated effects, provide insight into the mechanisms by which panaxynol suppresses murine colitis. Overall, this data is promising for the use of panaxynol to improve colitis in the clinic.NEW & NOTEWORTHY In the current study, we report that panaxynol ameliorates chemically induced murine colitis by improving colonic crypt and mucosal architecture, suppressing colitis-enriched microbes, reducing macrophages, and promoting the differentiation of regulatory T-cells in the colonic lamina propria. This study suggests that this novel natural compound may serve as a safe and effective treatment option for colitis patients.

Animal models of inflammatory bowel disease: category and evaluation indexes

Inflammatory bowel disease (IBD) research often relies on animal models to study the etiology, pathophysiology, and management of IBD. Among these models, rats and mice are frequently employed due to their practicality and genetic manipulability. However, for studies aiming to closely mimic human pathology, non-human primates such as monkeys and dogs offer valuable physiological parallels. Guinea pigs, while less commonly used, present unique advantages for investigating the intricate interplay between neurological and immunological factors in IBD. Additionally, New Zealand rabbits excel in endoscopic biopsy techniques, providing insights into mucosal inflammation and healing processes. Pigs, with their physiological similarities to humans, serve as ideal models for exploring the complex relationships between nutrition, metabolism, and immunity in IBD. Beyond mammals, non-mammalian organisms including zebrafish, Drosophila melanogaster, and nematodes offer specialized insights into specific aspects of IBD pathology, highlighting the diverse array of model systems available for advancing our understanding of this multifaceted disease. In this review, we conduct a thorough analysis of various animal models employed in IBD research, detailing their applications and essential experimental parameters. These include clinical observation, Disease Activity Index score, pathological assessment, intestinal barrier integrity, fibrosis, inflammatory markers, intestinal microbiome, and other critical parameters that are crucial for evaluating modeling success and drug efficacy in experimental mammalian studies. Overall, this review will serve as a valuable resource for researchers in the field of IBD, offering insights into the diverse array of animal models available and their respective applications in studying IBD.

Krill Oil and Its Bioactive Components as a Potential Therapy for Inflammatory Bowel Disease: Insights from In Vivo and In Vitro Studies

Krill oil is extracted from krill, a small crustacean in the Antarctic Ocean. It has received growing attention because of krill oil's unique properties and diverse health benefits. Recent experimental and clinical studies suggest that it has potential therapeutic benefits in preventing the development of a range of chronic conditions, including inflammatory bowel disease (IBD). Krill oil is enriched with long-chain n-3 polyunsaturated fatty acids, especially eicosapentaenoic and docosahexaenoic acids, and the potent antioxidant astaxanthin, contributing to its therapeutic properties. The possible underlying mechanisms of krill oil's health benefits include anti-inflammatory and antioxidant actions, maintaining intestinal barrier functions, and modulating gut microbiota. This review aims to provide an overview of the beneficial effects of krill oil and its bioactive components on intestinal inflammation and to discuss the findings on the molecular mechanisms associated with the role of krill oil in IBD prevention and treatment.

First Mexican Consensus on Crohn's disease

INTRODUCTION

Crohn's disease (CD) is a subtype of chronic and incurable inflammatory bowel disease. It can affect the entire gastrointestinal tract and its etiology is unknown.

OBJECTIVE

The aim of this consensus was to establish the most relevant aspects related to definitions, diagnosis, follow-up, medical treatment, and surgical treatment of Crohn's disease in Mexico.

MATERIAL AND METHODS

Mexican specialists in the areas of gastroenterology and inflammatory bowel disease were summoned. The consensus was divided into five modules, with 69 statements. Applying the Delphi panel method, the pre-meeting questions were sent to the participants, to be edited and weighted. At the face-to-face meeting, all the selected articles were shown, underlining their level of clinical evidence; all the statements were discussed, and a final vote was carried out, determining the percentage of agreement for each statement.

RESULTS

The first Mexican consensus on Crohn's disease was produced, in which recommendations for definitions, classifications, diagnostic aspects, follow-up, medical treatment, and surgical treatment were established.

CONCLUSIONS

Updated recommendations are provided that focus on definitions, classifications, diagnostic criteria, follow-up, and guidelines for conventional medical treatment, biologic therapy, and small molecule treatment, as well as surgical management.

Long-term behavior and functional outcomes of ileal-pouch anal anastomosis in inflammatory bowel disease with changing phenotype

BACKGROUND

Ileal-pouch-anal anastomosis is the operation of choice after proctocolectomy for ulcerative colitis; some patients will develop Crohn's disease. We aim to determine long-term behavior and outcomes of inflammatory bowel disease-ileal-pouch-anal anastomosis after colectomy, where a specialist gastrointestinal pathologist re-evaluated the initial colectomy specimen.

METHODS

Patients with inflammatory bowel disease-ileal-pouch-anal anastomosis were identified from a single-surgeon prospective database containing 1,165 patients accrued from 1991 to 2017 and invited to complete pouch-function and quality-of-life assessments. Medical records were used to obtain clinical outcomes and subjective functional assessments for those unable to be contacted. Data were compared between patients with and without histological assessment disagreement and subsequent inflammatory bowel disease behavior subgroups.

RESULTS

For 138 patients included in the analysis, the median follow-up was 22.5 (range: 5-39) years. A total of 39.1% of patients had histologic diagnostic change after gastrointestinal pathologist review, and 19% and 39% developed Crohn's disease-like disease behavior at 10- and 20-year follow-ups. Pouch function and quality-of-life scores were similar across diagnostic change subgroups. Pouch failure was higher in Crohn's-like disease (31.1 vs 13.0%, P < .05). Intestinal continuity was maintained in 68.9% of Crohn's disease-like patients, 57.9% required biologics. Gastrointestinal pathologist review did not alter the time to new diagnosis (P = .419) or time to pouch failure (P = .320), mean: 11.0 and 11.41 years, respectively.

CONCLUSION

We describe equivocal patient-reported outcomes in patients with ileal-pouch-anal anastomosis and changing histologic and clinical diagnosis. Although pouch excision and biologic use rates are higher, many Crohn's disease-like patients maintain their pouch. Diagnostic change and pouch failure often occur >10 years after ileal-pouch-anal anastomosis creation. This supports the consideration of ileal-pouch-anal anastomosis after colectomy in carefully selected patients with inflammatory bowel disease, even those with ambiguous histology and the need for close long-term follow-up.

Gut virome in inflammatory bowel disease and beyond

OBJECTIVE

The gut virome is a dense community of viruses inhabiting the gastrointestinal tract and an integral part of the microbiota. The virome coexists with the other components of the microbiota and with the host in a dynamic equilibrium, serving as a key contributor to the maintenance of intestinal homeostasis and functions. However, this equilibrium can be interrupted in certain pathological states, including inflammatory bowel disease, causing dysbiosis that may participate in disease pathogenesis. Nevertheless, whether virome dysbiosis is a causal or bystander event requires further clarification.

DESIGN

This review seeks to summarise the latest advancements in the study of the gut virome, highlighting its cross-talk with the mucosal microenvironment. It explores how cutting-edge technologies may build upon current knowledge to advance research in this field. An overview of virome transplantation in diseased gastrointestinal tracts is provided along with insights into the development of innovative virome-based therapeutics to improve clinical management.

RESULTS

Gut virome dysbiosis, primarily driven by the expansion of Caudovirales, has been shown to impact intestinal immunity and barrier functions, influencing overall intestinal homeostasis. Although emerging innovative technologies still need further implementation, they display the unprecedented potential to better characterise virome composition and delineate its role in intestinal diseases.

CONCLUSIONS

The field of gut virome is progressively expanding, thanks to the advancements of sequencing technologies and bioinformatic pipelines. These have contributed to a better understanding of how virome dysbiosis is linked to intestinal disease pathogenesis and how the modulation of virome composition may help the clinical intervention to ameliorate gut disease management.

Tumefactive Crohn's Disease Mimicking Colon Carcinoma in a Young Female: A Case Report

Tumefactive Crohn's disease is a rare form of Crohn's disease that may mimic colon carcinoma macroscopically. This case report describes a 28-year-old female who presented with right-sided abdominal pain and a palpable abdominal mass that had persisted for over a month. Multiple hospitalizations failed to provide an accurate diagnosis until an exploratory laparotomy revealed that the "mass" was the cecum and a perforated ascending colon. A partial right colectomy was performed, sending the specimen for biopsy. The microscopic description showed dense and confluent chronic inflammation in the colonic mucosa and wall, extending to the serosa in some regions. The infiltration comprised lymphocytes and plasma cells, with an admixture of some neutrophils. Aphthous mucosal ulcerations, intramural fissures, and fistulas were present. Immunostains for pan-keratin demonstrated no intramural epithelial elements. The characteristics of this lesion represent tumefactive Crohn's disease. This case highlights the key microscopic characteristics that pathologists look for when differentiating Crohn's disease from colon carcinoma in a patient presenting with abdominal pain and a colon mass.

A rare differential diagnosis of inflammatory bowel disease in a young male patient; a challenging case report

Background

Chronic granulomatous disease (CGD) is a rare disorder normally diagnosed in infancy.

Case presentation

A 27-year-old man admitted with non-specific symptoms of CGD first underwent endoscopy, and colonoscopy procedures as primary evaluation of clinical presentation. Eighteen months after the first admission, he was referred to the emergency department for hematemesis, and critical situations, such as a severe anemic with Hgb= 2.6 mg/dl. As a result of this specific clinical presentation, urgent emergency treatment was performed, and endoscopic examination revealed ulcers and abnormalities in the duodenal bulb and jejunum. Other imaging procedures, such as sonography, and abdominal CT scans, showed splenomegaly. He underwent splenectomy, and after that, endoscopic treatment with balloon TTS dilation was scheduled, but this procedure failed. So, we decided to do a gastro-jujenostomy that alleviated the clinical symptoms. After nine months, he was referred to GOO, and endoscopic evaluation showed giant ulceration with severe stricture in the duodenum, and a polyp in the jejunostomy. Finally, Based on clinical presentation and pathologic evidence of biopsies, the patient approached CGD as the final diagnosis.

Conclusion

Step-by-step, rule out of different highly suspicious diseases may result in a definite CGD diagnosis, and rapid management of these patients may increase the chance of survival.

Association of Periodontal Disease with Activity of Crohn's Disease

INTRODUCTION

Crohn's disease (CD) is a chronic inflammatory granulomatous disease that can affect the entire gastrointestinal tract. It is characterized by various extraintestinal manifestations (EIMs), of which oral manifestations (OMs) are often possible. One of the possible OMs is periodontal disease (PD), a chronic inflammatory condition of the supporting tissues of the teeth. This study aimed to show the existence of a mutual relationship between the clinical activity of PD and the clinical and endoscopic activity of CD.

MATERIALS AND METHODS

One clinical and two endoscopic indexes were used for the assessment of CD activity and clinical attachment loss (CAL), bleeding on probing (BOP), pocket probing depth (PPD), and radiographic bone loss (RBL) in a dental panoramic tomogram to assess PD in CD patients.

RESULTS

A total of 38 patients underwent the entire study process, of which 20 patients had CD and 18 patients had CD and PD. Considering all CD activity scores, there were 26 patients with active disease; half of them had PD, and 85.7% of operated patients had active CD. The values of CAL, PPD, BOP, and RBL were higher in active CD patients than those in remission, except for BOP when comparing to the CDAI score, which was higher in those in remission of CD.

CONCLUSION

The results of this study indicate that there is a connection between the activity of CD and worse conditions of the supporting tissues of the gums in the oral cavity, so it is important to keep in mind the necessity of referring patients with CD to a dentist for timely and adequate therapeutic measures.

ATAT: Automated Tissue Alignment and Traversal in Spatial Transcriptomics with Self-Supervised Learning

Spatial transcriptomics (ST) has enhanced RNA analysis in tissue biopsies, but interpreting these data is challenging without expert input. We present Automated Tissue Alignment and Traversal (ATAT), a novel computational framework designed to enhance ST analysis in the context of multiple and complex tissue architectures and morphologies, such as those found in biopsies of the gastrointestinal tract. ATAT utilizes self-supervised contrastive learning on hematoxylin and eosin (H&E) stained images to automate the alignment and traversal of ST data. This approach addresses a critical gap in current ST analysis methodologies, which rely heavily on manual annotation and pathologist expertise to delineate regions of interest for accurate gene expression modeling. Our framework not only streamlines the alignment of multiple ST samples, but also demonstrates robustness in modeling gene expression transitions across specific regions. Additionally, we highlight the ability of ATAT to traverse complex tissue topologies in real-world cases from various individuals and conditions. Our method successfully elucidates differences in immune infiltration patterns across the intestinal wall, enabling the modeling of transcriptional changes across histological layers. We show that ATAT achieves comparable performance to the state-of-the-art method, while alleviating the burden of manual annotation and enabling alignment of tissue samples with complex morphologies.

Checkpoint Inhibitor-Induced Colitis: From Pathogenesis to Management

The advent of immunotherapy, specifically of immune checkpoint inhibitors (ICIs), for the treatment of solid tumors has deeply transformed therapeutic algorithms in medical oncology. Approximately one-third of patients treated with ICIs may de velop immune-related adverse events, and the gastrointestinal tract is often affected by different grades of mucosal inflammation. Checkpoint inhibitors colitis (CIC) presents with watery or bloody diarrhea and, in the case of severe symptoms, requires ICIs discontinuation. The pathogenesis of CIC is multifactorial and still partially unknown: anti-tumor activity that collaterally effects the colonic tissue and the upregulation of specific systemic inflammatory pathways (i.e., CD8+ cytotoxic and CD4+ T lymphocytes) are mainly involved. Many questions remain regarding treatment timing and options, and biological treatment, especially with anti-TNF alpha, can be offered to these patients with the aim of rapidly resuming oncological therapies. CIC shares similar pathogenesis and aspects with inflammatory bowel disease (IBD) and the use of ICI in IBD patients is under evaluation. This review aims to summarize the pathogenetic mechanism underlying CIC and to discuss the current evidenced-based management options, including the role of biological therapy, emphasizing the relevant clinical impact on CIC and the need for prompt recognition and treatment.

Growth Failure and Primary Amenorrhea: Endocrine Dysfunction as a Late Presentation of Crohn's Disease

Crohn's disease (CD) is a chronic inflammatory bowel disease involving entire gastrointestinal tract, most commonly affecting terminal ileum and colon. It usually presents with gastrointestinal symptoms like bloody diarrhea, fever and loss of weight. The clinical course of CD includes gastrointestinal complications like fistulas, abscesses and perianal disease. Inflammatory bowel diseases (IBD) are usually diagnosed during childhood and adolescence, majority during puberty and pubertal growth spurt. Various extraintestinal manifestations may be a presentation of CD that poses a diagnostic challenge. Growth failure is an important complication of IBD rather than a manifestation. Herein we present a case of a 16-year-old Sri Lankan girl presenting with growth failure and primary amenorrhea. She had minimal gastrointestinal symptoms. She also had microcytic anemia with marginally elevated inflammatory markers and hormonal profile. She underwent colonoscopy and was diagnosed to have Crohn's disease confirmed by ileal biopsy. On initiation of treatment with immunosuppressants, she attained menarche, although no improvement in height was observed.

Inflammatory Bowel Diseases: Does One Histological Score Fit All?

Mucosal healing (MH) is the main treatment target in ulcerative colitis (UC) and Crohn's disease, and it is defined by the combination of complete endoscopic and histologic remission. The complete resolution of mucosal inflammation should be confirmed by histology but its assessment is not always univocal. Neutrophil infiltration represents the unique histological marker in discriminating the active vs. quiescent phases of the disease, together with crypt injuries (cryptitis and crypt abscesses), erosions, and ulcerations. On the contrary, basal plasmacytosis is not indicative of activity or the remission of inflammatory bowel diseases (IBDs) but instead represents a diagnostic clue, mostly at the onset. Several histological scoring systems have been developed to assess grade severity, particularly for UC. However, most are complex and/or subjective. The aim of this review was to summarize available scores, their characteristics and limitations, and to present the advantages of a simplified mucosa healing scheme (SHMHS) based on neutrophils and their distribution in the gut mucosa. Finally, we overview future developments including artificial intelligence models for standardization of disease assessments and novel molecular markers of inflammation with potential application in diagnostic practice.

Validation of the Padova Prognostic Score for Colitis in Predicting Long-Term Outcome After Restorative Proctocolectomy

BACKGROUND

In 10%-20% of cases it is impossible to make a differential diagnosis between ulcerative colitis and Crohn's colitis. A 50% failure rate of J pouch ilea-anal anastomosis is observed in Crohn's colitis. In 2009, we created the Padua Prognostic Score for Colitis (PPSC) to predict the long-term clinical and functional outcome and quality of life of patients undergoing restorative proctocolectomy with J pouch. The aim of the present study is to establish and validate the accuracy of a prognostic score for chronic inflammatory bowel diseases (IBD).

PATIENT POPULATION AND METHODS

The PPSC was created in 2009 by integrating clinical and histological information of patients undergoing RPC. It included preoperative perianal abscess or fistula, rectal sparing, terminal ileum involvement, skip lesions and histological diagnosis of indeterminate colitis or Crohn's colitis on the operative specimen. The validity of this score was tested in predicting postoperative abscess or fistula, anal canal disease, pouchitis, pouch failure and new diagnosis of Crohn's disease. Correlation analysis, ROC curve analysis and survival analysis were used to validate the PPSC in a different cohort from the previous one.

RESULTS

We retrospectively enrolled in this study 138 consecutive patients undergoing CPR for ulcerative colitis (n = 127) or indeterminate colitis (n = 11) in our institution since 2005 to 2020. In this period, we observed 11 patients with postoperative abscess or fistula, 3 with anal canal disease, 40 with pouchitis, 6 with pouch failure and 6 with new diagnosis of Crohn's disease. In the new validation cohort, the PPSC confirmed to have a good accuracy in predicting the onset of postoperative CD (AUC = 74.5%, p = 0.018). Kaplan Meier curves demonstrate how a PPSC over 1 can reliably predicts the long-term onset of, pouchitis (p = 0.002) and anal abscess or fistulae (p = 0.04).

CONCLUSIONS

In this validation study we confirmed the accuracy of the PPSC in predicting postoperative fistulas or abscesses and pouchitis. Therefore, we believe that in clinical practice patients with a PPSC score greater than 1 should be warned of this risk of possible Crohn's disease diagnosis and pouch failure.

Ileal Pouch-Anal Anastomosis and Pouchitis: The Role of the Microbiota in the Pathogenesis and Therapy

Inflammatory bowel diseases, Crohn's disease and ulcerative colitis, are life-long disorders characterized by the chronic relapsing inflammation of the gastrointestinal tract with the intermittent need for escalation treatment and, eventually, even surgery. The total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical intervention of choice in subjects affected by ulcerative colitis (UC). Although IPAA provides satisfactory functional outcomes, it can be susceptible to some complications, including pouchitis as the most common. Furthermore, 10-20% of the pouchitis may develop into chronic pouchitis. The etiology of pouchitis is mostly unclear. However, the efficacy of antibiotics in pouchitis suggests that the dysbiosis of the IPAA microbiota plays an important role in its pathogenesis. We aimed to review the role of the microbiota in the pathogenesis and as a target therapy in subjects who develop pouchitis after undergoing the surgical intervention of total proctocolectomy with IPAA reconstruction.

Intramucosal Calprotectin Expression in Inflammatory Bowel Disease (IBD) and Non-IBD Colorectal Inflammation

BACKGROUND: Inflammatory bowel disease (IBD) diagnosis remains a challenge accompanied with high numbers of misdiagnosis causing suboptimal management. Tons of trials have been conducted to improve the diagnostic accuracy, one of which is the use of biomarker such as calprotectin. Calprotectin can be detected in tissue (intramucosal) and is becoming a potential marker of IBD. AIM: This study aims to determine intramucosal calprotectin expression in IBD, non-IBD colitis, and control. METHODS: This analytic retrospective study included consecutively sampled IBD and non-IBD colitis colorectal biopsy specimens, and control group obtained from Cipto Mangunkusumo Hospital registered from 2017 to 2019. Cases were included in the study if specimens were indicative of IBD and non-IBD clinically and histopathologically and no abnormality were found histopathologically in the control group. Specimens with non-adequate data from the hospital medical records or with missing tissue slides were excluded from the study. Calprotectin immunostaining was conducted to evaluate mean intramucosal calprotectin expression (cell/HPF) in each group. RESULTS: Most of the samples from IBD and non-IBD group (45 samples each) showed mild active inflammation. Mucosal calprotectin expression in aforementioned groups was higher than that of control group (p < 0.001). Subjects with active inflammation showed higher calprotectin expression compared to those with inactive inflammation (p < 0.001). Calprotectin expression was also related to activity grade. CONCLUSION: Higher calprotectin expression showed significant association with the presence of inflammation and disease activity. However, the application of intramucosal calprotectin immunohistochemistry test to determine inflammatory etiology (IBD vs. non-IBD) still needs to be further evaluated.

Pattern-based Histologic Approach in Very Early Onset IBD: Main Features and Differential Diagnosis

Very early onset inflammatory bowel disease (VEO-IBD) is a clinical umbrella classification composed of IBD-like diseases encompassing both classic IBD (Crohn's disease and ulcerative colitis) and monogenic disorder, both arising before 6 years of age. VEO-IBD patients present significant clinical differences from IBD occurring in older children and in adults, including more severe disease, often unresponsive to conventional IBD therapy and a greater proportion of cases featuring an underlying genetic alteration. Histologic findings of gastrointestinal biopsies can show an IBD-like pattern (both Crohn's disease-like and ulcerative colitis-like pattern), an apoptotic-like and enterocolitis-like pattern. Findings of specific morphologic alterations, such as villous blunting, apoptosis, dense eosinophilic infiltrates, lack of plasma cells and severe glandular atrophy, can suggest a monogenic disorder. Moreover, individuals with monogenic disorders may develop significant problems such as primary immunodeficiency, impacting treatment options. Finally, IBD histology in childhood can differ from that in older patients and adults. This complexity makes a differential diagnosis between IBD and other pediatric diseases involving the gastrointestinal tract difficult, especially considering that histologic features can be similar between different diseases. Without an appropriate diagnosis, the clinical course of VEO-IBD has greater potential for escalated treatment regimens involving extensive surgery and more intensive medical therapies rather than specific therapy directed toward the underlying defect. For these reasons, a pattern-based histologic approach correlated with clinical and laboratory findings with a multidisciplinary approach is fundamental to reach a correct diagnosis in an adequate clinical context.

Very Early Onset-IBD: evidence for the need of a multidisciplinary approach

Very early onset inflammatory bowel disease (VEO-IBD) represents approximately 25% of cases of IBD-like colitis occurring during childhood and, by definition, it is characterized by an onset prior to 6 years of age. This subgroup of patients presents significant differences from IBD occurring in older children and in adults, including a more severe clinical course, a reduced responsiveness to conventional IBD therapy, and a greater proportion of cases featuring an underlying monogenic disorder. Histological findings from gastro-intestinal (GI) biopsies are characterized by an IBD-like, apoptotic or enterocolitis-like pattern, complicating the differential diagnosis with other pediatric diseases involving GI tract. Moreover, individuals with monogenic disorders may develop significant comorbidities, such as primary immunodeficiency (PID), impacting treatment options. Without an appropriate diagnosis, the clinical course of VEO-IBD has greater potential for escalated treatment regimens involving extensive surgery, more intensive medical therapies and, even more important, inadequate recognition of underlying monogenic defect that may lead to inappropriate (sometimes fatal) therapy. For these reasons, an adequate context leading to an appropriate diagnosis is imperative, calling for a close collaboration between pediatricians, pathologists, geneticists, and immunologists.

Sampling and Reporting of Inflammatory Bowel Disease

Pathologists have an important and expanding role in the diagnosis and management of inflammatory bowel disease. This role includes the initial diagnosis of the disease, assessment of the response to treatment and the identification of short-term complications such as cytomegalovirus infection and long-term complications such as dysplasia. Furthermore, the assessment of resection specimens for complication of disease is important to determining the risk of subsequent disease or inflammation within an ileal pouch. Adequate sampling of the disease at endoscopy and from the surgical resection specimen is vital to determining the ultimate information that can be provided by the pathologist. This sampling is determined by the clinical scenario. Similarly, a standardized approach to reporting and synthesizing the histologic findings will improve patient management. This is best exemplified by the increasing interest in histologic activity indices, such as the Nancy index in ulcerative colitis, and in the standardized reporting for inflammatory bowel disease dysplasia recommended by the SCENIC international consensus.

Histopathology of Non-IBD Colitis. A practical approach from the Italian Group for the study of the gastrointestinal tract (GIPAD)

Non-IBD colitides (NIBDC) are intestinal diseases clinically and endoscopically overlapping with Inflammatory Bowel Diseases (IBD), sometimes with a similar histological picture. NIBDC include entities such as infectious colitis, ischemic colitis, pseudomembranous colitis, eosinophilic colitis, autoimmune enterocolitis, segmental colitis associated with diverticulosis, drug-induced colitis, radiation-induced colitis, diversion colitis, and microscopic colitis, this last including two entities: collagenous and lymphocytic colitis. The knowledge of the most useful histological features and the main clinical data for each entity is mandatory in daily clinical practice, for correct pathological diagnosis and clinical management.