Histopathological evaluation of colonic mucosal biopsy specimens in chronic inflammatory bowel disease: diagnostic implications

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.

A Combination of Pathological Features Identifies Crohn's Disease in Surgical Bowel Resection Specimens

BACKGROUND

Diagnosis of Crohn's disease is challenging. This study aims to compare the histological features of Crohn's disease and non-Crohn's disease (other intestinal inflammatory diseases) in surgical specimens to identify a set of histologic features distinguishing Crohn's disease from non-Crohn's disease.

METHODS

Patients with Crohn's disease (N = 171) and patients with non-Crohn's disease (N = 215) diagnosed between 2010 and 2015 who had surgical bowel resection were identified. The frequency of histological features in surgical resection specimens was compared between these two groups.

RESULTS

Univariate analysis revealed that transmural inflammation, subserosal lymphoid aggregates, fissures or sinus-like structures, granulomas or granuloma-like nodules, abnormalities of the enteric nervous system, and mucosa structure alterations (muscularis mucosa thickening or mucosal atrophy with pseudopyloric gland metaplasia) were more frequent in Crohn's disease than non-Crohn's disease cases (p < 0.001 for all). Some of the above histologic features were further grouped as chronic inflammatory change which includes granulomas or granuloma-like nodules, lymphoid aggregates in the muscularis propria or subserosa, fissures or sinus-like structures, and architectural abnormality which is defined as the presence of abnormal enteric nervous system and/or mucosa structural alterations (muscularis mucosa thickening or mucosal atrophy with pseudopyloric gland metaplasia). A combination of transmural inflammation, chronic inflammatory change, and architectural abnormality had a sensitivity of 92.4% and a specificity of 97.7% for Crohn's disease.

CONCLUSIONS

In surgical bowel resection specimens, a combination of transmural inflammation, chronic inflammatory change, and architectural abnormality help diagnose Crohn's disease.

Definitions of Histological Abnormalities in Inflammatory Bowel Disease: an ECCO Position Paper

Histological assessment of endoscopic biopsies in inflammatory bowel disease [IBD] plays an important role in clinical management, investigative studies, and clinical trials. Scoring schemes consisting of multiple histological items and offering considerable precision are widely available. However, definitions of histological abnormalities are often inconsistent. Furthermore, interobserver variability for their recognition and assessment may be high. The European Crohn's and Colitis Organisation [ECCO] formed an expert panel to explore definitions of histological abnormalities in IBD, with the aim of improving the quality of diagnosis and facilitating development of scoring schemes. The process confirmed that the current definitions often have no evidence base and vary between sources. Using available evidence and expert knowledge, the panel produced a series of ECCO consensus position statements on histological features in IBD.

The Histology-Driven Differential Diagnosis in Bowel Inflammatory Conditions Is Not All That Obvious: Evidence from a Survey Based on Digital Slides

(1) Background: when the pathologist faces histologic slides from colonoscopies in daily practice, given the large number of entities and etiologies under inflammatory bowel conditions, in-depth definition of the histological spectrum and the recommendations of current guidelines are often not enough to conclusively define a diagnostic framework. Histological patterns should be organized hierarchically in flowcharts that consider the correlation with clinical data. We conducted an online survey asking a group of gastroenteropathologists to apply a pattern classification based on the most significant lesions in colitis differential diagnosis: crypt distortion and activity. (2) Methods: digital slides from 20 endoscopy samples were analyzed by twenty pathologists and classified according to the occurrence of crypt distortion (nondestructive-destructive colitis) and subsequently to the evidence of activity (ND1-2-3, D1-2). (3) Results: in 8 out of 20 (40%) cases, the participants reached a full agreement regarding the evaluation of crypt distortion (5 cases: nondestructive colitis; 3 cases: destructive colitis). The calculated agreement was k = 0.432. In the second-level quiz (ND1-2-3 and D1-2), full agreement between participants was achieved for 7 of the 28 (25%) possible classifications, with k = 0.229. (4) Conclusions: The findings from this survey are indicative of an unexpectedly low consensus, even among dedicated pathologists, about the recognition of histological changes that are commonly considered critical lesions in the histologic identification of bowel non-neoplastic diseases. In our opinion, these divergences imply a significant risk of misdiagnosis of bowel inflammatory conditions, hampering the usefulness of histological assessment.

The Number of Colon Crypts in Digital Mucosal Samples: A New Independent Parameter for Diagnosing Ulcerative Colitis

Background/Aim

It has been demonstrated that most routine biopsies from the colon and rectum display cross-cut crypts (CCC). The aim was to assess the number of CCC in microscopic isometric digital samples (0.500 mm2) from routine colon biopsies.

Patients and Methods

Colon biopsies from 224 patients were investigated: 99 in patients with ulcerative colitis (UC), 31 UC in remission (UCR), 28 infectious colitis (IC), 7 resolved IC (RIC), 19 diverticular sigmoiditis (DS), and 40 normal colon mucosa (NCM).

Results

A total of 8,024 CCC were registered: 2,860 (35.6%) in UC, 1,319 UCR (16.4%), 849 (10.6%) in IC, 340 (4.2%) in RIC, 795 (9.9%) in DS, and 1,861 (23.2%) in NCM. The CCC frequencies in UC and IC were significantly lower (p<0.05) than those in UCR, RIC, DS, and NCM.

Conclusion

By the simple algorithm of counting CCC in standardized isometric microscopic digital circles measuring 0.500 mm2, it was possible to differentiate between UC (long-lasting inflammation) and IC (short-lasting inflammation) on the one hand, and UCR, RIC, DS (persistent inflammation), and NCM, on the other. The counting of CCC in the algorithm by five pathologists working in three disparate European Countries, was found to be reproducible.

Novel histological repertoire of crypt-associated anomalies in inflamed colon mucosa

AIMS

Studying crypt branching in ulcerative colitis (UC) and in infectious colitis (IC), we detected previously unreported crypt-associated anomalies (CAAs). The objective was to describe, illustrate and assess the frequency of CAAs in inflamed colon mucosa in patients with UC and IC.

METHODS

Sections from 100 consecutive biopsies with UC, in 50 with IC and in 27 with UC in remission (UCR) were reviewed. The following CAAs were identified: crypt eosinophilia, intracryptal epithelial hyperplasia, intracryptal epithelial budding, intracryptal supernumerary crypts, intracryptal epithelial bridges, crypt rings in rows and off-centre epithelial budding.

RESULTS

The frequency of crypts with extensive crypt eosinophilia and with intracryptal epithelial budding was significantly higher in UC than in IC and UCR (p<0.05); the frequency in the remaining histological parameters was similar in UC, IC and UCR.

CONCLUSIONS

CAAs were found interspersed with branching crypts. CAAs persisted in long-lasting UC mucosal inflammation, but declined when the inflammation waned. Since similar anomalies are not present in normal colon mucosa, the results suggest that CAAs had been boosted by the ongoing mucosal inflammation. The development of these previously unreported CAAs in the colon mucosa with inflammation might embody pathological aberrations of cryptogenesis.

Virtual Fluorescence Translation for Biological Tissue by Conditional Generative Adversarial Network

Fluorescence labeling and imaging provide an opportunity to observe the structure of biological tissues, playing a crucial role in the field of histopathology. However, when labeling and imaging biological tissues, there are still some challenges, e.g., time-consuming tissue preparation steps, expensive reagents, and signal bias due to photobleaching. To overcome these limitations, we present a deep-learning-based method for fluorescence translation of tissue sections, which is achieved by conditional generative adversarial network (cGAN). Experimental results from mouse kidney tissues demonstrate that the proposed method can predict the other types of fluorescence images from one raw fluorescence image, and implement the virtual multi-label fluorescent staining by merging the generated different fluorescence images as well. Moreover, this proposed method can also effectively reduce the time-consuming and laborious preparation in imaging processes, and further saves the cost and time.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43657-023-00094-1.

Intestinal epithelial barrier integrity investigated by label-free techniques in ulcerative colitis patients

The intestinal epithelial barrier, among other compartments such as the mucosal immune system, contributes to the maintenance of intestinal homeostasis. Therefore, any disturbance within the epithelial layer could lead to intestinal permeability and promote mucosal inflammation. Considering that disintegration of the intestinal epithelial barrier is a key element in the etiology of ulcerative colitis, further assessment of barrier integrity could contribute to a better understanding of the role of epithelial barrier defects in ulcerative colitis (UC), one major form of chronic inflammatory bowel disease. Herein, we employ fast, non-destructive, and label-free non-linear methods, namely coherent anti-Stokes Raman scattering (CARS), second harmonic generation (SHG), two-photon excited fluorescence (TPEF), and two-photon fluorescence lifetime imaging (2P-FLIM), to assess the morpho-chemical contributions leading to the dysfunction of the epithelial barrier. For the first time, the formation of epithelial barrier gaps was directly visualized, without sophisticated data analysis procedures, by the 3D analysis of the colonic mucosa from severely inflamed UC patients. The results were compared with histopathological and immunofluorescence images and validated using transmission electron microscopy (TEM) to indicate structural alterations of the apical junction complex as the underlying cause for the formation of the epithelial barrier gaps. Our findings suggest the potential advantage of non-linear multimodal imaging is to give precise, detailed, and direct visualization of the epithelial barrier in the gastrointestinal tract, which can be combined with a fiber probe for future endomicroscopy measurements during real-time in vivo imaging.

Therapeutic Effects of Aloe saponaria against Ulcerative Colitis Induced by Dextran Sulfate Sodium

Aloe vera (A. vera) has been studied as a treatment option for ulcerative colitis (UC), but there is a lack of scientific evidence showing whether treatment with Aloe saponaria (A. saponaria) can also be beneficial. To investigate the therapeutic potential of A. saponaria as a treatment for UC, clinical symptoms, histopathological characteristics of the colon, inflammatory response, and toxicity were analyzed in dextran sulfate sodium (DSS)-induced UC mice after administration of aqueous extracts of A. saponaria (AAS) for 7 days. The total polyphenol and tannin content of AAS was 272 µg/g and 163 µg/g, respectively. AAS exhibited significant antioxidant activity. Several clinical symptoms, including body weight, colon length, and hematochezia, remarkably improved in the DSS+AAS treated group compared to the DSS+Vehicle-treated group. In addition, similar improvements were detected in the histopathological characteristics and mucin-secreting ability in the colon of DSS-induced UC mice after the administration of AAS. The levels of infiltrated inflammatory cells and cytokine expression were significantly decreased in a dose-dependent manner in the colon of the DSS+AAS-treated group. These alterations in inflammatory response were accompanied by a significant recovery of the protein kinase C/extracellular signal-regulated kinase (PKC/ERK) and phosphatidylinositol-3-kinase/serine-threonine protein kinase (PI3K/Akt) signaling pathways. However, the levels of key markers for hepatotoxicity and nephrotoxicity consistently remained between those of the DSS+AAS-treated and the No groups. Therefore, the results of the present study provide novel evidence that AAS may improve the clinical symptoms and attenuate the inflammatory response in DSS-induced UC mice and does not have any significant hepatotoxicity or nephrotoxicity.

Inflammatory Bowel Disease: Clinical Diagnosis and Pharmaceutical Management

Inflammatory bowel disease has an enormous impact on public health, medical systems, economies, and social conditions. Biologic therapy has ameliorated the treatment and clinical course of patients with inflammatory bowel disease. The efficacy and safety profiles of currently available therapies are still less that optimal in numerous ways, highlighting the requirement for new therapeutic targets. A bunch of new drug studies are underway in inflammatory bowel disease with promising results. This is an outlined guideline of clinical diagnosis and pharmaceutical therapy of inflammatory bowel disease. Outline delineates the overall recommendations on the modern principles of desirable practice to bolster the adoption of best implementations and exploration as well as inflammatory bowel disease patient, gastroenterologist, and other healthcare provider education. Inflammatory bowel disease encompasses Crohn's disease and ulcerative colitis, the two unsolved medical inflammatory bowel disease-subtypes condition with no drug for cure. The signs and symptoms on first presentation relate to the anatomical localization and severity of the disease and less with the resulting diagnosis that can clinically and histologically be non-definitive to interpret and establish criteria, specifically in colonic inflammatory bowel disease when the establishment is inconclusive is classified as indeterminate colitis. Conservative pharmaceuticals and accessible avenues do not depend on the disease phenotype. The first line management is to manage symptoms and stabilize active disease; at the same time maintenance therapy is indicated. Nutrition and diet do not play a primary therapeutic role but is warranted as supportive care. There is need of special guideline that explore solution of groundwork gap in terms of access limitations to inflammatory bowel disease care, particularly in developing countries and the irregular representation of socioeconomic stratification with a strategic plan, for the unanswered questions and perspective for the future, especially during the surfaced global COVID-19 pandemic caused by coronavirus SARS-CoV2 impacting on both the patient's psychological functioning and endoscopy services. Establishment of a global registry system and accumulated experiences have led to consensus for inflammatory bowel disease management under the COVID-19 pandemic. Painstakingly, the pandemic has influenced medical care systems for these patients. I briefly herein viewpoint summarize among other updates the telemedicine roles during the pandemic and how operationally inflammatory bowel disease centers managed patients and ensured quality of care. In conclusion: inflammatory bowel disease has become a global emergent disease. Serious medical errors are public health problem observed in developing nations i.e., to distinguish inflammatory bowel disease and infectious and parasitic diseases. Refractory inflammatory bowel disease is a still significant challenge in the management of patients with Crohn's disease and ulcerative colitis. There are gaps in knowledge and future research directions on the recent newly registered pharmaceuticals. The main clinical outcomes for inflammatory bowel disease were maintained during the COVID-19 pandemic period.

Retrospective Evaluation of the Most Frequently Observed Histological Changes in Duodenal and Rectal Mucosal Biopsies in Horses with Recurrent Colic

Colic, a condition affecting the gastrointestinal tract of horses, manifests as severe pain and may be a life-threatening condition. It is possible to distinguish between an acute, disposable process, as well as recurrent colic symptoms (abdominal pain) caused by an ongoing chronic inflammatory process. This paper presents a retrospective analysis of the histopathological findings of duodenal and rectal samples taken from horses with recurrent colic, with the aim to determine the frequency and extent of inflammation. The samples, i.e., duodenal biopsy (60 samples) and rectal biopsy (17 samples), were taken from 77 horses showing recurrent colic symptoms. Histopathological examination included staining with hematoxylin and eosin. The examination included evaluation of the superficial epithelium, mucosal lamina propria, and submucosa. All samples from the duodenum and rectum showed the presence of leukocyte infiltration in the mucosal lamina propria. The most frequently observed cellular infiltration was a moderate infiltration consisting of lymphocytes and plasma cells in duodenum and mixed populations of plasma cells, lymphocytes, and eosinophilia in the rectum. Mott cells were also noted among the inflammatory infiltrates. More than one-fourth of the horses were found to have shortened intestinal villi. The results presented here showed the involvement of inflammation in the course of recurrent colic, which can be both its cause (by impairing motility and absorption) and its effect (as a result of obstruction or ischemia).

Inflammatory Bowel Disease: Clinical Diagnosis and Surgical Treatment-Overview

This article is an overview of guidelines for the clinical diagnosis and surgical treatment of predominantly colonic inflammatory bowel diseases (IBD). This overview describes the systematically and comprehensively multidisciplinary recommendations based on the updated principles of evidence-based literature to promote the adoption of best surgical practices and research as well as patient and specialized healthcare provider education. Colonic IBD represents idiopathic, chronic, inflammatory disorders encompassing Crohn's colitis (CC) and ulcerative colitis (UC), the two unsolved medical subtypes of this condition, which present similarity in their clinical and histopathological characteristics. The standard state-of-the-art classification diagnostic steps are disease evaluation and assessment according to the Montreal classification to enable explicit communication with professionals. The signs and symptoms on first presentation are mainly connected with the anatomical localization and severity of the disease and less with the resulting diagnosis "CC" or "UC". This can clinically and histologically be non-definitive to interpret to establish criteria and is classified as indeterminate colitis (IC). Conservative surgical intervention varies depending on the disease phenotype and accessible avenues. The World Gastroenterology Organizations has, for this reason, recommended guidelines for clinical diagnosis and management. Surgical intervention is indicated when conservative treatment is ineffective (refractory), during intractable gastrointestinal hemorrhage, in obstructive gastrointestinal luminal stenosis (due to fibrotic scar tissue), or in the case of abscesses, peritonitis, or complicated fistula formation. The risk of colitis-associated colorectal cancer is realizable in IBD patients before and after restorative proctocolectomy with ileal pouch-anal anastomosis. Therefore, endoscopic surveillance strategies, aimed at the early detection of dysplasia, are recommended. During the COVID-19 pandemic, IBD patients continued to be admitted for IBD-related surgical interventions. Virtual and phone call follow-ups reinforcing the continuity of care are recommended. There is a need for special guidelines that explore solutions to the groundwork gap in terms of access limitations to IBD care in developing countries, and the irregular representation of socioeconomic stratification needs a strategic plan for how to address this serious emerging challenge in the global pandemic.

Branching crypts in inflammatory bowel disease revisited

Histologic sections from patients with inflammatory bowel disease (IBD) usually exhibit crypts with architectural distortions and branching crypts. It has been postulated that crypt branching should be assessed only in well-oriented, upright crypts. However, those crypts are mostly found in sections from colectomy specimens and colon mucosectomies. Sections from endoscopic biopsies are fortuitously cut in a horizontal plane, a procedure mostly revealing cross-cut crypt rings. In endoscopic biopsies from UC patients we previously detected cross-cut crypts heralding the crest domain of branching crypts. Recently, the scrutiny of biopsies from IBD patients revealed that branching-crest domains concurred either with crypts in symmetric branching, typified by twin, amalgamating back-to-back isometrics crypt-rings, or with crypts in asymmetric branching, characterized by ≥2 amalgamating anisometric crypt-rings; both symmetric and asymmetric branching-crest domains were encased by a thin muscularis mucosae. Quantitative studies in biopsies from Swedish and German patients with IBD showed that crypts in asymmetric branching outnumbered those in symmetric branching. Because crypt-branching seldom occurs in the normal colon in adults and considering that colon crypts typically divide once or twice during a lifetime, the accruing of asymmetric branching crypts in IBD biopsies emerges as a significant histologic parameter. Although the biological significance of asymmetric crypt-branching in IBD remains at present elusive, their occurrence deserves to be further investigated. The future policy will be to include in our pathologic reports, the number of crypts in asymmetric branching, in order to monitor their frequency in prospective surveillance biopsies in patients with IBD.

Histopathological Features in Colonic Biopsies at Diagnosis Predict Long-term Disease Course in Patients with Crohn's Disease

BACKGROUND AND AIMS

Crohn's disease [CD] is characterised by a heterogeneous disease course. Patient stratification at diagnosis using clinical, serological, or genetic markers does not predict disease course sufficiently to facilitate clinical decision making. The current study aimed to investigate the additive predictive value of histopathological features to discriminate between a long-term mild and severe disease course.

METHODS

Diagnostic biopsies from treatment-naïve CD patients with mild or severe disease courses in the first 10 years after diagnosis were reviewed by two gastrointestinal pathologists after developing a standardised form comprising 15 histopathological features. Multivariable logistic regression models were built to identify predictive features and compute receiver operating characteristic [ROC] curves. Models were internally validated using bootstrapping to obtain optimism-corrected performance estimates.

RESULTS

In total, 817 biopsies from 137 patients [64 mild, 73 severe cases] were included. Using clinical baseline characteristics, disease course could only moderately be predicted (area under receiver operating characteristic curve [AUROC]: 0.738 [optimism 0.018], 95% confidence interval [CI] 0.65-0.83, sensitivity 83.6%, specificity 53.1%). When adding histopathological features, in colonic biopsies a combination of [1] basal plasmacytosis, [2] severe lymphocyte infiltration in lamina propria, [3] Paneth cell metaplasia, and [4] absence of ulcers were identified and resulted in significantly better prediction of a severe course (AUROC: 0.883 [optimism 0.033], 95% CI 0.82-0.94, sensitivity 80.4%, specificity 84.2%).

CONCLUSIONS

In this first study investigating the additive predictive value of histopathological features in biopsies at CD diagnosis, we found that certain features of chronic inflammation in colonic biopsies contributed to prediction of a severe disease course, thereby presenting a novel approach to improving stratification and facilitating clinical decision making.

Histological Hallmarks of Mucosal Healing in Inflammatory Bowel Diseases in the Era of Monoclonal Antibodies Therapy: New Insights and Perspectives

BACKGROUND

Chronic inflammatory bowel diseases (IBDs) are gaining increasing attention, both because they can severely reduce the quantity and quality of life, and because the advent of monoclonal antibodies has profoundly changed the natural history of these diseases. In recent years, the concept of mucosal healing has assumed a certain importance, and there are more and more clinical and pharmacological trials that consider this parameter among their endpoints, so much so that it may soon be included among the desirable clinical outcomes of patients with IBD.

METHODS

We performed a literature review of the Pubmed, Medline, and Web of Science (WoS) databases.

RESULTS

We selected 88 articles and then removed 6 duplicates; the final sample after accurate application of the inclusion criteria numbered 73 articles, with a level of evidence rating of three or four, according to Oxfords Evidence-based medicine. Our aim was to study the histological impact of monoclonal antibody therapies on mucosal healing, taking into consideration the few studies present in the literature. To perform this review, we compared studies that examined patients with Crohn's disease (CD) and/or ulcerative colitis (UC) undergoing monoclonal therapy versus patients undergoing other non-biological therapies (PICO statements).

CONCLUSIONS

We try to delineate how monoclonal antibodies have changed the natural history of IBD, acting at the microscopic level, and we believe that a careful analysis of the histopathology and the definition of the objective criteria for "Mucosa Healing" should enable this concept to be included among the clinical endpoints of patients affected by IBD, thus contributing to a better therapeutic management of these patients.

High-fidelity and rapid cellular-level Mueller matrix imaging for tissue identification with unstained sections

Mueller matrix polarimetry is regarded as a promising technique in the field of biomedicine, especially for pathological diagnosis. However, the current studies on Mueller imaging of pathological sections are all at the tissue-level, and the cellular-level polarization information is difficult to obtain. To overcome this challenge, we first propose a cellular-level Mueller matrix imaging method for accurate quantitative identification of tissues in this study. Benefiting from the significant birefringent behavior of paraffin in unstained sections, the proposed method can locate the paraffin distribution areas of retardance images by involving Otsu's algorithm. Then, the real cellular-level polarization information (e.g., depolarization) is acquired. The efficiency of the proposed method was demonstrated on unstained rat tissue samples. The results showed that the obtained depolarization images are highly consistent with the stained microscopic images in terms of the morphology and arrangement of the tissues at cellular level. Finally, this method was preliminarily applied to the detection of human lung cancer tissue section, effectively realizing the quantitative differentiation of normal, inflamed, and malignant areas in unstained section. This study provides a possible approach for the rapid and accurate diagnosis of cancer.

ECCO Topical Review Optimising Reporting in Surgery, Endoscopy, and Histopathology

BACKGROUND AND AIMS

Diagnosis and management of inflammatory bowel diseases [IBD] requires a lifelong multidisciplinary approach. The quality of medical reporting is crucial in this context. The present topical review addresses the need for optimised reporting in endoscopy, surgery, and histopathology.

METHODS

A consensus expert panel consisting of gastroenterologists, surgeons, and pathologists, convened by the European Crohn's and Colitis Organisation, performed a systematic literature review. The following topics were covered: in endoscopy: [i] general IBD endoscopy; [ii] disease activity and surveillance; [iii] endoscopy treatment in IBD; in surgery: [iv] medical history with surgical relevance, surgical indication, and strategy; [v] operative approach; [vi] intraoperative disease description; [vii] operative steps; in pathology: [viii] macroscopic assessment and interpretation of resection specimens; [ix] IBD histology, including biopsies, surgical resections, and neoplasia; [x] IBD histology conclusion and report. Statements were developed using a Delphi methodology incorporating two consecutive rounds. Current practice positions were set when ≥ 80% of participants agreed on a recommendation.

RESULTS

Thirty practice positions established a standard terminology for optimal reporting in endoscopy, surgery, and histopathology. Assessment of disease activity, surveillance recommendations, advice to surgeons for operative indication and strategies, including margins and extent of resection, and diagnostic criteria of IBD, as well as guidance for the interpretation of dysplasia and cancer, were handled. A standardised report including a core set of items to include in each specialty report, was defined.

CONCLUSIONS

Interdisciplinary high-quality care requires thorough and standardised reporting across specialties. This topical review offers an actionable framework and practice recommendations to optimise reporting in endoscopy, surgery, and histopathology.

Accurate Classification of Pediatric Colonic Inflammatory Bowel Disease Subtype Using a Random Forest Machine Learning Classifier

BACKGROUND

The pediatric inflammatory bowel disease (PIBD) classes algorithm was developed to bring consistency to labelling of colonic IBD, but labels are exclusively based on features atypical for ulcerative colitis (UC).

AIM

The aim of the study was to develop an algorithm and identify features that discriminate between pediatric UC and colonic Crohn disease (CD).

METHODS

Baseline clinical, endoscopic, radiologic, and histologic data, including the PIBD class features in 74 colonic IBD (56: UC, 18: colonic CD) patients were collected. The PIBD class features and additional features common to UC were used to perform initial clustering, using similarity network fusion (SNF). We trained a Random Forest (RF) classifier on the full dataset and used a leave-one-out approach to evaluate model accuracy. The top-features were used to build a new classifier, which we tested on 15 previously unused patients. We then performed clustering with SNF on the top RF features and assessed ability to discriminate between UC and colonic-CD independent of a supervised model.

RESULTS

The initial SNF clustering with 58 patients demonstrated 2 groups: group 1 (n = 39, 90% UC) and group 2 (n = 19, 68% colonic-CD). Our RF classifier correctly labelled 97% of the 58 patients based on leave-one-out cross validation and identified the 7 most important features (3 histological and 4 endoscopic) to clinically distinguish these groups. We trained a new RF classifier with the top 7 features and found 100% accuracy in a set of 15 held-out patients. Finally, post hoc clustering with these 7 features revealed 2 groups of patients: group 1 (n = 55, 98% UC) and group 2 (n = 18, 94% colonic-CD).

CONCLUSIONS

A combination of supervised and unsupervised analyses identified a short list of features, which consistently distinguish UC from colonic CD. Future directions include validation in other populations.

Protective effects of fermented rice extract on ulcerative colitis induced by dextran sodium sulfate in mice

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD), characterized by the gut mucosal ulceration. Growing evidence indicates that dysregulation of immune response to the commensal microbiota involves the pathogenesis of IBD. Previous studies have demonstrated the favorable probiotic effects of fermented rice extracts through triple fermentation with Saccharomyces cerevisiae and Weissella cibaria (FRe). Thus, the therapeutic potential of FRe for UC was examined. Dextran sodium sulfate UC mice model was orally administered distilled water as a control, sulfasalazine, or FRe at 300, 200, and 100 mg/kg, once a day for a week. The UC control exhibited body weight loss, bloody stools, and colonic shortening. However, the FRe, especially at 300 mg/kg, led to a reduction in weight loss, disease activity index scores, and colon weight, and an increase in colorectal length. The histopathological analyses revealed mild changes involved in the colonic crypt and mucosal damages in the FRe groups, along with inhibited inflammation. Indeed, the FRe reduced neutrophil infiltration and production of proinflammatory cytokines (i.e., tumor necrosis factor-α, interleukin-6/-8). This was accompanied by the down-regulation of nuclear factor-kappa B. The gene expression responsible for the intestinal barrier integrity (i.e., Zonna occludens-1/-2, Claudin-1, Occludin, Mucin-1/-2) was up-regulated in the FRe groups. In addition, the FRe reduced lipid peroxidation and enhanced antioxidant activity. Interestingly, the microbiota dysbiosis was attenuated in the FRe groups, and the number of beneficial bacteria, Lactobacilli and Bifidobacteria, was increased. It suggests that the FRe potently ameliorate UC as a functional food.

Microproteomics and Immunohistochemistry Reveal Differences in Aldo-Keto Reductase Family 1 Member C3 in Tissue Specimens of Ulcerative Colitis and Crohn's Disease

PURPOSE

Differential diagnosis of ulcerative colitis (UC) and Crohn's disease (CD) is of utmost importance for the decision making of respective therapeutic treatment strategies but in about 10-15% of cases, a clinical and histopathological assessment does not lead to a definite diagnosis. The aim of the study is to characterize proteomic differences between UC and CD.

EXPERIMENTAL DESIGN

Microproteomics is performed on formalin-fixed paraffin-embedded colonic tissue specimens from 9 UC and 9 CD patients. Protein validation is performed using immunohistochemistry (IHC) (n_UC =51, n_CD =62, n_CTRL =10) followed by digital analysis.

RESULTS

Microproteomic analyses reveal eight proteins with higher abundance in CD compared to UC including proteins related to neutrophil activity and damage-associated molecular patterns. Moreover, one protein, Aldo-keto reductase family 1 member C3 (AKR1C3), is present in eight out of nine CD and absent in all UC samples. Digital IHC analysis reveal a higher percentage and an increased expression intensity of AKR1C3-positive epithelial cells in CD compared to UC and in controls compared to inflammatory bowel disease (IBD).

CONCLUSION AND CLINICAL RELEVANCE

Overall, the results suggest that microproteomics is an adequate tool to highlight protein patterns in IBD. IHC and digital pathology might support future differential diagnosis of UC and CD.

Differentiation of Colonic Inflammatory Bowel Disease: Re-examination of Paediatric Inflammatory Bowel Disease Classes Algorithm With Resected Colon As the Criterion Standard

OBJECTIVES

Differentiation of Crohn disease (CD) from ulcerative colitis (UC) is challenging when inflammation is predominantly colonic. The paediatric inflammatory bowel disease (PIBD) classes algorithm was developed to bring consistency to labelling, but used physician-assigned diagnosis as the criterion standard. We aimed to reassess the PIBD classes using pathology of subsequently resected colon as the criterion standard.

METHOD

Single-centre study of patients diagnosed with colonic IBD between 2002 and 2017 and subsequently treated with colectomy. Baseline pretreatment data were reviewed and the PIBD classes algorithm was independently applied by 2 reviewers to assign a label of UC/IBD-unclassified (IBD-U)/colonic-CD. Concordance between the algorithm-based, precolectomy clinical, and pathologic examination of resected colon diagnosis were assessed. Changes in diagnosis during postcolectomy follow-up were recorded.

RESULTS

Sixty-two children underwent colectomy for medically refractory colonic IBD. Diagnosis based on pathologic review of resected colon CD:4;UC:56;IBDU:2. The clinical, PIBD classes algorithm, and colectomy diagnoses were concordant in 51 of 62 patients (81%, Fleiss kappa 0.48). Precolectomy clinical diagnosis was concordant with colectomy diagnosis in 58 of 62 patients (94%, weighted-kappa 0.65). The PIBD classes label was concordant with colectomy diagnosis in 51 of 62 patients (82%, weighted-kappa 0.38); resected colon pathology was typical of UC in 6 patients with PIBD classes label of IBD-U based on single class 2 feature and in 3 with PIBD classes label of CD based on single class 1 feature.

CONCLUSIONS

Concordance of PIBD classes algorithm diagnosis applied before colectomy with a diagnostic label based on pathologic examination of a subsequently resected colon is only fair. Caution is needed in stringent application of colonic CD and IBD-U labels based on presence of single feature.

Atypical Presentation of Acquired Hypoganglionosis in a Patient Taking Clozapine

Acquired hypoganglionosis (HG) is a rare enteric gastrointestinal neuromuscular disorder previously associated with chronic inflammation that can lead to constipation, ileus, and even death. There is little known about the pathophysiology of acquired hypoganglionosis, and it is unclear if medications are related to the development of the disease. Clozapine is an atypical antipsychotic used to treat refractory schizophrenia that is well known for its side effects including agranulocytosis and gastrointestinal dysmotility. This is an unusual case of acquired hypoganglionosis in a patient with anticholinergic toxicity on clozapine therapy.

Clinical and intestinal histologic features of horses treated for recurrent colic: 66 cases (2006-2015)

OBJECTIVE To describe gastrointestinal histologic findings for horses with recurrent colic and evaluate possible associations between initial clinical signs, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge. DESIGN Retrospective case series. ANIMALS 66 horses with a history of recurrent colic for which gastrointestinal specimens had been submitted for histologic examination. PROCEDURES Histologic diagnosis was categorized as inflammatory, neoplastic, ischemic, other, and undiagnosed. Relationships among initial clinical features, biopsy method, histologic diagnosis, and outcome 1 year after hospital discharge (ie, alive vs dead and persistent recurrent colic [yes vs no]) and between corticosteroid treatment and outcome were investigated. Odds ratios and hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. RESULTS Inflammatory disease (36/66 [55%]) was the most common histologic diagnosis. Horses undergoing rectal biopsy alone were significantly (OR, 14.4; 95% Cl, 2.7 to 76.1) more likely to not have a histologic diagnosis than were horses in which other biopsy methods were used. In multivariable modelling, persistence of recurrent colic (HR, 15.2; 95% Cl, 1.9 to 121.2) and a history of weight loss (HR, 4.9; 95% Cl, 1.4 to 16.5) were significantly associated with outcome (alive vs dead) 1 year after surgery. Corticosteroid treatment was not significantly associated with either outcome. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that a high proportion (36/66 [55%]) of horses with recurrent colic had inflammatory gastrointestinal disease. Use of rectal biopsy alone to obtain biopsy specimens was more likely to result in no histologic diagnosis. Use of corticosteroids in horses with inflammatory gastrointestinal disease was not associated with outcome but warrants further investigation.

A comprehensive review and update on ulcerative colitis. Dis Mon 2019;65:100851. [PMID: 30837080 DOI: 10.1016/j.disamonth.2019.02.004]

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disorder of the colon that causes continuous mucosal inflammation extending from the rectum to the more proximal colon, with variable extents. UC is characterized by a relapsing and remitting course. UC was first described by Samuel Wilks in 1859 and it is more common than Crohn's disease worldwide. The overall incidence and prevalence of UC is reported to be 1.2-20.3 and 7.6-245 cases per 100,000 persons/year respectively. UC has a bimodal age distribution with an incidence peak in the 2nd or 3rd decades and followed by second peak between 50 and 80 years of age. The key risk factors for UC include genetics, environmental factors, autoimmunity and gut microbiota. The classic presentation of UC include bloody diarrhea with or without mucus, rectal urgency, tenesmus, and variable degrees of abdominal pain that is often relieved by defecation. UC is diagnosed based on the combination of clinical presentation, endoscopic findings, histology, and the absence of alternative diagnoses. In addition to confirming the diagnosis of UC, it is also important to define the extent and severity of inflammation, which aids in the selection of appropriate treatment and for predicting the patient's prognosis. Ileocolonoscopy with biopsy is the only way to make a definitive diagnosis of UC. A pathognomonic finding of UC is the presence of continuous colonic inflammation characterized by erythema, loss of normal vascular pattern, granularity, erosions, friability, bleeding, and ulcerations, with distinct demarcation between inflamed and non-inflamed bowel. Histopathology is the definitive tool in diagnosing UC, assessing the disease severity and identifying intraepithelial neoplasia (dysplasia) or cancer. The classical histological changes in UC include decreased crypt density, crypt architectural distortion, irregular mucosal surface and heavy diffuse transmucosal inflammation, in the absence of genuine granulomas. Abdominal computed tomographic (CT) scanning is the preferred initial radiographic imaging study in UC patients with acute abdominal symptoms. The hallmark CT finding of UC is mural thickening with a mean wall thickness of 8 mm, as opposed to a 2-3 mm mean wall thickness of the normal colon. The Mayo scoring system is a commonly used index to assess disease severity and monitor patients during therapy. The goals of treatment in UC are three fold-improve quality of life, achieve steroid free remission and minimize the risk of cancer. The choice of treatment depends on disease extent, severity and the course of the disease. For proctitis, topical 5-aminosalicylic acid (5-ASA) drugs are used as the first line agents. UC patients with more extensive or severe disease should be treated with a combination of oral and topical 5-ASA drugs +/- corticosteroids to induce remission. Patients with severe UC need to be hospitalized for treatment. The options in these patients include intravenous steroids and if refractory, calcineurin inhibitors (cyclosporine, tacrolimus) or tumor necrosis factor-α antibodies (infliximab) are utilized. Once remission is induced, patients are then continued on appropriate medications to maintain remission. Indications for emergency surgery include refractory toxic megacolon, colonic perforation, or severe colorectal bleeding.

Prevalence of Mycobacterium avium subspecies paratuberculosis IS 900 DNA in biopsy tissues from patients with Crohn's disease: histopathological and molecular comparison with Johne's disease in Fars province of Iran

BACKGROUND

Crohn's disease is a chronic enteritis of humans that affects the gastrointestinal tract, especially the terminal ileum, cecum and colon. The etiology of this disease is still unknown but seems to be multifactorial. There are reports about the potential link between Crohn's disease in humans and the causative agent of Johne's disease in ruminants. Because of the prevalence of Johne's disease in the Fars Province of Iran, the aim of this study was to investigate the prevalence of MAP in the biopsy tissues of patients affected by Crohn's disease in this area.

METHODS

The study was performed from April 2015 to June 2017 at Namazi Hospital, Shiraz University of Medical Sciences, and School of Veterinary Medicine, Shiraz University, Shiraz, Iran. Intestinal biopsies of 30 patients (12 male and 18 female; mean age, 34 years; range 4-77 years) with the confirmed diagnosis of Crohn's disease and 30 patients diagnosed as non-inflammatory bowel disease (19 male and 11 female; mean age, 38 years; range 13-68 years) were studied by molecular, histopathological and histochemical methods. Also, similar numbers of adult goats affected by Johne's disease were studied, comparatively. DNA extractions of tissue specimens were subjected to PCR to amplify a 413-bp sequence of the IS900 gene.

RESULTS

Using IS900-PCR, the overall prevalence of MAP in patients affected by Crohn's disease and non-inflammatory bowel disease were 47 and 13%, respectively. In addition, the prevalence of MAP in goats affected by Johne's disease was 70%. Using acid-fast histochemical staining, only 7% of Crohn's disease patients were weakly positive as paucibacillary and 43% of Johne's disease cases were moderate to strongly positive as multibacillary. Histopathologically, granulomatous enteritis (83 and 90%), lymphoplasmacytic enteritis (17 and 14%), edema and lymphangiectasia (67 and 96%), and vasculitis (20 and 73%) were common findings in Crohn's and Johne's diseases, respectively.

CONCLUSION

Our findings demonstrate a remarkable association between MAP and CD in this population, and support an etiologic relationship between MAP infection in humans and the development of CD. MAP infection in human tissue may display species-specific pathologic findings, as occurs with other zoonotic pathogens.

NLRP3-Dependent and -Independent Processing of Interleukin (IL)-1β in Active Ulcerative Colitis

A contributing factor in the development of ulcerative colitis (UC) and Crohn’s disease (CD) is the disruption of innate and adaptive signaling pathways due to aberrant cytokine production. The cytokine, interleukin (IL)-1β, is highly inflammatory and its production is tightly regulated through transcriptional control and both inflammasome-dependent and inflammasome- independent proteolytic cleavage. In this study, qRT-PCR, immunohistochemistry, immunofluorescence confocal microscopy were used to (1) assess the mRNA expression of NLRP3, IL-1β, CASP1 and ASC in paired biopsies from UC and CD patient, and (2) the colonic localization and spatial relationship of NLRP3 and IL-1β in active and quiescent disease. NLRP3 and IL-1β were found to be upregulated in active UC and CD. During active disease, IL-1β was localized to the infiltrate of lamina propria immune cells, which contrasts with the near-exclusive epithelial cell layer expression during non-inflammatory conditions. In active disease, NLRP3 was consistently expressed within the neutrophils and other immune cells of the lamina propria and absent from the epithelial cell layer. The disparity in spatial localization of IL-1β and NLRP3, observed only in active UC, which is characterized by a neutrophil-dominated lamina propria cell population, implies inflammasome-independent processing of IL-1β. Consistent with other acute inflammatory conditions, these results suggest that blocking both caspase-1 and neutrophil-derived serine proteases may provide an additional therapeutic option for treating active UC.

Chronic regional intestinal inflammatory disease: A trans-species slow infection?

Crohn's disease and ulcerative colitis in humans and paratuberculosis in domestic and wild ruminants can be defined as chronic regional intestinal inflammatory diseases (CRIID). This review is a literature overview on these diseases in humans, non-human primates, dogs, cats, rabbits, equids and ruminants with a focus on pathological and microbiological features aimed identifying common characteristics that could lead to a unified pathological classification for a better understanding of their mechanisms and causes. The result is a framework of inflammatory forms throughout the different species indicative of common mechanisms of the slow infection type characterized by a time course varying from weeks to months or even years, and where the inflammatory component would be more prominent in the intestinal interphase between host and environment and be morphologically characterized by an infiltrate ranging from lymphoplasmacytic to histiocytic. This should provide new insights for causation demonstration and therapeutic approaches in human IBD.

Histologic scoring indices for evaluation of disease activity in Crohn's disease

BACKGROUND

Histologic assessment of mucosal disease activity has been increasingly used in clinical trials of treatment for Crohn's disease. However, the operating properties of the currently existing histologic scoring indices remain unclear.

OBJECTIVES

A systematic review was undertaken to evaluate the development and operating characteristics of available histologic disease activity indices in Crohn's disease.

SEARCH METHODS

Electronic searches of MEDLINE, EMBASE, PubMed, and the Cochrane Library (CENTRAL) databases from inception to 20 July 2016 were supplemented by manual reviews of bibliographies and abstracts submitted to major gastroenterology meetings (Digestive Disease Week, United European Gastroenterology Week, European Crohn's and Colitis Organisation).

SELECTION CRITERIA

Any study design (e.g. randomised controlled trial, cohort study, case series) that evaluated a histologic disease activity index in patients with Crohn's disease was considered for inclusion. Study participants included adult patients (> 16 years), diagnosed with Crohn's disease using conventional clinical, radiographic or endoscopic criteria.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the titles and abstracts of the studies identified from the literature search. The full text of potentially relevant citations were reviewed for inclusion and the study investigators were contacted as needed for clarification. Any disagreements regarding study eligibility were resolved by discussion and consensus with a third author.Two authors independently extracted and recorded data using a standard form. The following data were recorded from each eligible study: number of patients enrolled; number of patients per treatment arm; patient characteristics: age and gender distribution; description of histologic disease activity index utilized; and outcomes such as content validity, construct validity, criterion validity, responsiveness, intra-rater reliability, inter-rater reliability, and feasibility.

MAIN RESULTS

Sixteen reports of 14 studies describing 14 different numerical histological indices fulfilled the inclusion criteria.Inter-rater reliability was assessed in one study. For the Naini and Cortina Score, estimates of correlation were 'almost perfect', ranging from r = 0.94 to 0.96. The methodological quality of this study with respect to reliability was 'good'.With respect to validity, correlation estimates between various histological scoring systems and Crohn's disease activity as measured by objective markers of inflammation (including C-reactive protein, erythrocyte sedimentation rate, fecal calprotectin and fecal lactoferrin); endoscopic disease activity scores; clinical disease activity scores; and quality of life questionnaires were reported. Comparisons between histologic scoring indices and endoscopic scoring indices ranged from no correlation to 'substantial' (r = 0.779). The methodological quality of the studies that explored validity ranged form 'poor' to 'good'.Responsiveness data were available in seven studies. After subjects were administered a treatment of known efficacy, statistically significant change in the index score was demonstrated in five studies with respect to six indices. Two studies failed to indicate whether there was statistically significant change in the index score post-treatment. With regard to methodological quality, six of the studies were rated as 'poor' and one of the studies was rated as 'fair'.Feasibility was assessed by one study. The Naini and Cortina Score was shown to be simple to use and feasible for every given case.

AUTHORS' CONCLUSIONS

Currently there is no fully validated histological scoring index for evaluation of Crohn's disease activity. Development of a validated histological scoring index for Crohn's disease is a clinical and research priority.

Disruption of the Hedgehog signaling pathway in inflammatory bowel disease fosters chronic intestinal inflammation

Hedgehog (Hh) signaling is essential for intestinal homeostasis and has been associated with inflammation and tissue repair. We hypothesized that Hh signaling could affect the inflammatory process in inflammatory bowel disease (IBD). For this purpose, colon specimens from the inflamed and non-inflamed mucosa of 15 patients with Crohn's disease (CD), 15 with ulcerative colitis, and 15 controls were analyzed by immunohistochemistry and real-time PCR. The production and modulation of cytokines were measured by ELISA from culture explants. Apoptosis was assessed by TUNEL and caspase-3 activity assays. Chemotaxis was evaluated using a transwell system. Primary human intestinal and skin fibroblasts were used for analyzing migration and BrdU incorporation. Hh proteins were generally expressed at the superficial epithelium, and a marked reduction was observed in CD. In the lamina propria, Gli-1 predominantly co-localized with vimentin- and alpha-smooth muscle actin-positive cells, with lower levels observed in CD. In colon explants, Hh stimulation resulted in reduction, while blockade increased, TNF α, IL-17, and TGF β levels. Apoptotic rates were higher in inflamed samples, and they increased after Hh blockade. Levels of Gli-1 mRNA were negatively correlated with caspase-3 activity. Hh blockade increased chemoattraction of monocytes. Primary fibroblasts incorporated more BrdU, but migrated less after Hh blockade. These results suggest that Hh signaling provides a negative feedback to the lamina propria, down-regulating inflammatory cytokines, and inhibiting leukocyte migration and fibroblast proliferation, while favoring fibroblast migration. Therefore, Hh signaling is strongly implicated in the pathogenesis of intestinal inflammation, and it may represent a novel therapeutic target for IBD.

Epithelial IL-1R2 acts as a homeostatic regulator during remission of ulcerative colitis

Ulcerative colitis (UC) is a chronic intestinal inflammatory disease that may undergo periods of activity followed by remission. We aimed to identify the endogenous regulatory mechanisms that may promote disease remission. Transcriptional and protein analysis of the intestinal mucosa revealed that the IL-1 decoy receptor, interleukin-1 receptor type 2 (IL1R2), was upregulated in remission compared with active UC and controls. We identified epithelial cells as being responsible for increased IL-1R2 production during remission. Expression of IL1R2 was negatively regulated by Wnt/beta-catenin signals in colonic crypts or epithelial stem cell cultures; accordingly, epithelial stem cells upregulated IL-1R2 upon differentiation. Blocking IL-1R2 in isolated colonic crypt cultures of UC patients in remission and T-cell cultures stimulated with biopsy supernatant from UC patients in remission boosted IL-1β-dependent production of inflammation-related cytokines. Finally, IL1R2 transcription was significantly lower in patients that relapsed during a 1-year follow-up period compared with those in endoscopic remission. Collectively, our results reveal that the IL-1/IL-1R2 axis is differentially regulated in the remitting intestinal mucosa of UC patients. We hypothesize that IL-1R2 in the presence of low concentrations of IL-1β may act locally as a regulator of intestinal homeostasis.

Beyond endoscopic mucosal healing in UC: histological remission better predicts corticosteroid use and hospitalisation over 6 years of follow-up

BACKGROUND

Endoscopic mucosal healing is an established treatment target for UC, yet the value of achieving histological remission remains unclear.

AIMS

To evaluate histological remission compared to endoscopic mucosal healing for predicting patient outcomes in UC.

METHODS

Blinded assessment of endoscopic and histological measures of disease activity was performed on patients with established UC at baseline. Concordance and prognostic values of endoscopic mucosal healing (defined by Baron score ≤1) and histological remission (defined by Truelove and Richards' index) for predicting outcomes of corticosteroid use, hospitalisation and colectomy were determined over a median 6 years follow-up, including κ statistics and Cox regression multivariate analysis.

RESULTS

91 patients with UC were followed up for a median 72 months (IQR 54-75 months). Overall, concordance between endoscopic and histological remission was moderate (κ=0.56, 95% CI 0.36 to 0.77); 24% patients had persistent inflammation despite endoscopic remission. Histological remission predicted corticosteroid use and acute severe colitis requiring hospitalisation over the follow-up period (HR 0.42 (0.2 to 0.9), p=0.02; HR 0.21 (0.1 to 0.7), p=0.02; respectively), whereas endoscopic mucosal healing did not (HR 0.86, 95% CI 0.5 to 1.7, p0.65; HR 0.83 95% CI 0.3 to 2.4, p0.74; respectively).

CONCLUSIONS

Histological remission is a target distinct from endoscopic mucosal healing in UC and better predicts lower rates of corticosteroid use and acute severe colitis requiring hospitalisation, over a median of 6 years of follow-up. Our findings support the inclusion of histological indices in both UC clinical trials and practice, towards a target of 'complete remission'.

Investigation of potential early Histologic markers of pediatric inflammatory bowel disease

Background

Early manifestations of pediatric inflammatory bowel disease (IBD) can be relatively nonspecific. Initial mucosal biopsies may not be conclusive, delaying the diagnosis until subsequent biopsies demonstrate typical histologic features of IBD. We hypothesized that certain inflammatory cell types may be utilized as early histologic indicators of IBD in children.

Methods

A retrospective analysis compared histologic findings from initially inconclusive or negative endoscopic studies in 22 patients who were subsequently diagnosed with IBD (after diagnostic endoscopy) to those of 20 comparison patients with functional abdominal pain matched for age, gender, and study type. A pediatric pathologist, blinded to study group, reviewed biopsies for histologic abnormalities. Eosinophil densities were obtained from the stomach, duodenum, and rectosigmoid areas. Immunohistochemistry (IHC) staining for tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-9 (MMP-9) was performed on the stomach and rectosigmoid areas.

Results

Gastritis and colonic crypt distortion were present in the IBD group at a greater rate (61 % vs. 22 %, p = 0.020; 34 % vs. 4 %, p = 0.008, respectively). Peak and mean eosinophil densities in the rectosigmoid area were greater in the IBD group (17.0/hpf vs. 5.0/hpf, p = 0.0063; 12.3/hpf vs. 4.2/hpf, p = 0.0106, respectively). TNF-α and MMP-9 staining did not reveal any significant differences.

Conclusions

Our data suggests that significantly greater inflammation in the stomach, crypt distortion in the colon, and eosinophilia in the rectosigmoid distinguished the IBD group from the comparison group at the time of the initial endoscopic evaluation.

Quantitative assessment of CD30+ lymphocytes and eosinophils for the histopathological differential diagnosis of inflammatory bowel disease

BACKGROUND AND AIMS

The histopathological discrimination of Crohn's disease [CD] and ulcerative colitis [UC] can be challenging. The aim of this study was to evaluate if quantification of CD30(+) lymphocytes and eosinophils in histopathological material improves the accuracy of diagnosis of inflammatory bowel disease.

METHODS

A total of 156 patients were diagnosed with IBD by a gastroenterologist and corroborated by 5 years of follow-up. Patients were treatment naïve at the time of biopsy. Samples were taken from diseased areas of the colon and examined by a gastrointestinal pathologist.

RESULTS

The median number of eosinophils in biopsies from affected segments was 42/high power field [hpf] [25.5-63.5] in CD and 98/hpf [67-123] in UC [p < 0.001]. Biopsies containing ≥ 70 eosinophils/hpf field had a sensitivity of 78.3% and a specificity of 71% for the diagnosis of UC ({area under the receiver operating characteristic (ROC) curve 0.767 (95% confidence interval [CI] 0.696-0.838)}. There was a median of three CD30(+) cells/hpf [range 2-6] in diseased CD biopsies and 33 cells/hpf [24-52] in diseased UC biopsies [p < 0.001]. The cut-off determined by the ROC curve was 15 (sensitivity 97.4%, specificity 97.4%, positive likelihood ratio (PLR) 17.1, Negative likelihood ratio (NLR) 0.03, area under the curve [AUC]: 0.978; 95% CI 0.95310.999).

CONCLUSIONS

Routine histopathological assessment with quantification of CD30+ cells is highly accurate at discriminating CD and UC. All the measured parameters are easy to perform, low-cost, and available in most pathological laboratories.

Systematic review: histological remission in inflammatory bowel disease. Is 'complete' remission the new treatment paradigm? An IOIBD initiative

BACKGROUND AND AIMS

Advances in the medical management of inflammatory bowel disease (IBD) have altered treatment targets. Endoscopic mucosal healing is associated with better outcomes in IBD, though less is known about the significance of achieving histological remission. Our aim was to perform a systematic review to investigate whether histological or 'complete' remission constitutes a further therapeutic target in IBD.

METHODS

A bibliographic search was performed on the 1st of October 2013 and subsequently on the 1st of March 2014 of online databases (OVID SP MEDLINE, OVID EMBASE, National Pubmed Central Medline, Cochrane Library, ISI, conference abstracts), using MeSH terms and key words: ("inflammatory bowel diseases" OR "crohn disease" OR "ulcerative colitis" OR "colitis") AND ("mucosal healing" OR "histological healing" OR "pathological healing" OR "histological scoring" OR "pathological scoring").

RESULTS

The search returned 2951 articles. 120 articles were cited in the final analysis. There is no validated definition of histological remission in IBD. There are 22 different histological scoring systems for IBD, none of which are fully validated. Microscopic inflammation persists in 16-100% of cases of endoscopically quiescent disease. There is evidence that histological remission may predict risk of complications in ulcerative colitis beyond endoscopic mucosal healing, though data are scarce in Crohn's disease.

CONCLUSIONS

Histological remission in IBD represents a target distinct from endoscopic mucosal healing, not yet routinely sought in clinical trials or practice. There remains a need for a standardized and validated histological scoring system and to confirm the prognostic value of histological remission as a treatment target in IBD.

Diagnosis of inflammatory bowel disease: Potential role of molecular biometrics

Accurate diagnosis of predominantly colonic inflammatory bowel disease (IBD) is not possible in 30% of patients. For decades, scientists have worked to find a solution to improve diagnostic accuracy for IBD, encompassing Crohn's colitis and ulcerative colitis. Evaluating protein patterns in surgical pathology colectomy specimens of colonic mucosal and submucosal compartments, individually, has potential for diagnostic medicine by identifying integrally independent, phenotype-specific cellular and molecular characteristics. Mass spectrometry (MS) and imaging (I) MS are analytical technologies that directly measure molecular species in clinical specimens, contributing to the in-depth understanding of biological molecules. The biometric-system complexity and functional diversity is well suited to proteomic and diagnostic studies. The direct analysis of cells and tissues by Matrix-Assisted-Laser Desorption/Ionization (MALDI) MS/IMS has relevant medical diagnostic potential. MALDI-MS/IMS detection generates molecular signatures obtained from specific cell types within tissue sections. Herein discussed is a perspective on the use of MALDI-MS/IMS and bioinformatics technologies for detection of molecular-biometric patterns and identification of differentiating proteins. I also discuss a perspective on the global challenge of transferring technologies to clinical laboratories dealing with IBD issues. The significance of serologic-immunometric advances is also discussed.

Diagnosis of inflammatory bowel disease: Potential role of molecular biometrics

Accurate diagnosis of predominantly colonic inflammatory bowel disease (IBD) is not possible in 30% of patients. For decades, scientists have worked to find a solution to improve diagnostic accuracy for IBD, encompassing Crohn’s colitis and ulcerative colitis. Evaluating protein patterns in surgical pathology colectomy specimens of colonic mucosal and submucosal compartments, individually, has potential for diagnostic medicine by identifying integrally independent, phenotype-specific cellular and molecular characteristics. Mass spectrometry (MS) and imaging (I) MS are analytical technologies that directly measure molecular species in clinical specimens, contributing to the in-depth understanding of biological molecules. The biometric-system complexity and functional diversity is well suited to proteomic and diagnostic studies. The direct analysis of cells and tissues by Matrix-Assisted-Laser Desorption/Ionization (MALDI) MS/IMS has relevant medical diagnostic potential. MALDI-MS/IMS detection generates molecular signatures obtained from specific cell types within tissue sections. Herein discussed is a perspective on the use of MALDI-MS/IMS and bioinformatics technologies for detection of molecular-biometric patterns and identification of differentiating proteins. I also discuss a perspective on the global challenge of transferring technologies to clinical laboratories dealing with IBD issues. The significance of serologic-immunometric advances is also discussed.

Endoscopic biopsy samples of naïve "colitides" patients: role of basal plasmacytosis

BACKGROUND

Although it is usually not difficult to diagnose inflammatory bowel disease (IBD) on surgical resection specimens, difficulties sometimes arise in differentiating these entities from other forms of colitis on endoscopic biopsy specimens. Basal plasmacytosis is considered as an early feature of IBD colitis, but it is rare in non-IBD colitides.

AIMS

We assessed the value of basal plasmacytosis as an individual variable in untreated patients with colitis.

PATIENTS AND METHODS

Archival slides of patients with untreated colitis (66 IBD and 49 non-IBD) and 20 controls with complete (from the terminal ileum to the rectum) endoscopic biopsy sampling were evaluated blindly for the presence of basal plasmacytosis and a possible association with the presence of eosinophils in the same anatomical location.

RESULTS

Overall, basal plasmacytosis was present in at least one anatomical segment in 58% of cases, and it was always present in patients with IBD, whereas it was sparsely found (9%) in patients with other colitides and in controls. Basal plasmacytosis in three or more segments had more than 80% probability for a patient to be classified as IBD, with the segmental distribution being different between ulcerative colitis and Crohn's disease. Additionally, basal plasmacytosis was always accompanied by eosinophils intermingled with plasma cells in the same anatomical position.

CONCLUSION

As an individual feature, basal plasmacytosis (accompanied by eosinophils) is a strong feature suggesting IBD, particularly when present in three or more colonic segments. This fact may be useful in the evaluation of endoscopic biopsies from patients with "colitis".

Colonoscopic evaluation in ulcerative colitis

Colonoscopic evaluation is an important tool in the evaluation of ulcerative colitis (UC). UC is divided by disease extent into proctitis, proctosigmoiditis, left-sided colitis, and pan-colitis. In addition, a cecal or peri-appendiceal patch and backwash ileitis are associated with UC. The extent and behavior of UC has been characterized further using various indices and scoring systems; among these systems is the Mayo Score, which is widely used in current clinical trials for new medications. As these medical therapies for UC have developed, achieving mucosal healing with medications has become an important therapeutic objective.

The histopathological approach to inflammatory bowel disease: a practice guide

Inflammatory bowel diseases (IBDs) are lifelong disorders predominantly present in developed countries. In their pathogenesis, an interaction between genetic and environmental factors is involved. This practice guide, prepared on behalf of the European Society of Pathology and the European Crohn's and Colitis Organisation, intends to provide a thorough basis for the histological evaluation of resection specimens and biopsy samples from patients with ulcerative colitis or Crohn's disease. Histopathologically, these diseases are characterised by the extent and the distribution of mucosal architectural abnormality, the cellularity of the lamina propria and the cell types present, but these features frequently overlap. If a definitive diagnosis is not possible, the term indeterminate colitis is used for resection specimens and the term inflammatory bowel disease unclassified for biopsies. Activity of disease is reflected by neutrophil granulocyte infiltration and epithelial damage. The evolution of the histological features that are useful for diagnosis is time- and disease-activity dependent: early disease and long-standing disease show different microscopic aspects. Likewise, the histopathology of childhood-onset IBD is distinctly different from adult-onset IBD. In the differential diagnosis of severe colitis refractory to immunosuppressive therapy, reactivation of latent cytomegalovirus (CMV) infection should be considered and CMV should be tested for in all patients. Finally, patients with longstanding IBD have an increased risk for the development of adenocarcinoma. Dysplasia is the universally used marker of an increased cancer risk, but inter-observer agreement is poor for the categories low-grade dysplasia and indefinite for dysplasia. A diagnosis of dysplasia should not be made by a single pathologist but needs to be confirmed by a pathologist with expertise in gastrointestinal pathology.

Endoscopic ultrasound of the colon for the differentiation of Crohn's disease and ulcerative colitis in comparison with healthy controls

BACKGROUND

Diagnosis of inflammatory bowel disease (IBD) is based on clinical presentation, colonoscopy and histology. Differentiation of Crohn's disease (CD) and ulcerative colitis (UC) can be difficult in some patients. Endoscopic ultrasound (EUS) provides high resolution images of the gastrointestinal wall (GI) and may be an alternative to differentiate CD/UC.

AIM

EUS of the GI layers in patients with IBD and healthy controls (HC) for the differential diagnosis of UC/CD in a prospective, blinded study.

METHODS

Consecutive patients with CD, UC or HC underwent EUS in the mid sigmoid colon with a forward-viewing radial echoendoscope. Mucosal, submucosal, total wall thickness (TWT) and locoregional lymphnodes (LN) were assessed by EUS in a blinded fashion. TWT was correlated with macroscopic IBD scores and histological inflammation scores.

RESULTS

Total wall thickness of 61 HC was 1.71 ± 0.02 mm, and 3.51 ± 0.15 mm in n = 52 with active IBD. In patients with active UC significant thickening of the mucosa was observed but nearly normal submucosa and m.propria. In active CD significant thickening of the submucosal layer was seen with nearly normal mucosa and m.propria [MucosaUC  = 2.08 ± 0.11 mm, MucosaCD  = 1.32 ± 0.17 mm (P = 0.0001); SubmucosaUC  = 1.01 ± 0.08 mm, SubmucosaCD  = 2.01 ± 0.22 mm (P = 0.0001)]. In 73.7% of patients with active CD, but in none with UC, paracolonic lymph nodes were detected. When mucosal-submucosal and TWT and LNs were combined, the sensitivity was 92.3% for the differentiation of active UC/CD. There was a strong correlation of TWT with histological inflammation scores (UC: r = 0.43; CD: r = 0.69).

CONCLUSIONS

Increased total wall thickness has a high positive predictive value for active IBD. EUS can differentiate active UC from CD and quantify the level of colonic inflammation.