Overlap in the spectrum of non-specific inflammatory bowel disease--'colitis indeterminate'

Development and validation of diagnosis model for inflammatory bowel diseases based on a serologic biomarker panel: A decision tree model study

BACKGROUND AND STUDY AIMS

Currently, an increasing amount of experimental data is available on newly discovered biomarkers in inflammatory bowel diseases (IBD), but the role of these biomarkers is often questionable due to their limited sensitivity. Therefore, this study aimed to build a diagnostic tool incorporating a panel of serum biomarkers into a computational algorithm to identify patients with IBD and differentiate those with Crohn's disease (CD) from those with ulcerative colitis (UC).

PATIENTS AND METHODS

We studied sera from 192 CD patients, 118 UC patients, 60 non-IBD controls and 60 healthy controls. Indirect immunofluorescence (IIF) assays were utilized to determine several serum biomarkers previously associated with IBD, and the decision tree algorithm was used to construct the diagnosis model. Performances of models were evaluated by prediction accuracy, precision, AUC and Matthews's correlation coefficient (MCC). The "Inflammatory Bowel Disease Multi-omics Database (IBDMDB)" cohorts were used to validate the model as external validation set.

RESULTS

The prediction rates were determined and compared for decision tree models after each data was developed using C5.0, C&RT, QUEST and CHAID. The C5.0 and CHAID algorithms, which ranked top for the prediction rate in the IBD vs. non-IBD model and the CD vs. UC model, respectively, were utilized for final pattern analysis. The final decision tree model achieved higher classification accuracy than the approach based on conservative marker combinations (sensitivity 75.0% vs. 79.5%, specificity 93.8% vs. 78.3% for differentiating IBD from non-IBD; and sensitivity 84.3% vs. 73.4%, specificity 92.5% vs. 54.9% for differentiating CD from UC, respectively). The model prediction consistency was 93% (28/30) in the external validation set.

CONCLUSION

The decision-tree-based approach used in this study, based on serum biomarkers, has shown to be a valid and useful approach to identifying IBD and differentiating CD from UC.

Clinical features of inflammatory bowel disease unclassified: a case-control study

BACKGROUND

Approximately 10-15% of inflammatory bowel disease (IBD) patients with overlapping features of ulcerative colitis (UC) and Crohn's disease (CD) are termed as inflammatory bowel disease unclassified (IBDU). This study aimed to describe the clinical features of IBDU and evaluate the potential associated factors of reclassification.

METHODS

The clinical data of 37 IBDU patients were retrospectively analyzed from November 2012 to November 2020. 74 UC and 74 CD patients were randomly selected and age- and sex-matched with the 37 IBDU patients. Clinical characteristics were compared between the three patient groups. Potential factors associated with the IBDU reclassification were evaluated.

RESULTS

60% of IBDU patients displayed rectal-sparing disease, and 70% of them displayed segmental disease. In comparison to UC and CD, the IBDU group demonstrated higher rates of gastrointestinal bleeding (32.4%), intestinal perforation (13.5%), spontaneous blood on endoscopy (51.4%), and progression (56.8%). The inflammation proceeded relatively slowly, manifesting as chronic alterations like pseudopolyps (78.4%) and haustra blunt or disappearance (56.8%). 60% of IBDU patients exhibited crypt abscess, and 16.7% of them exhibited fissuring ulcers or transmural lymphoid inflammation. The proportions of IBDU patients receiving immunosuppressants, surgery, and infliximab were basically the same as those of CD patients. During the 79 (66, 91) months of follow-up, 24.3% of IBDU patients were reclassified as UC, while 21.6% were reclassified as CD. The presence of intestinal hemorrhaging was associated with CD reclassification, while hypoalbuminemia was associated with UC reclassification.

CONCLUSIONS

IBDU may evolve into UC or CD during follow-up, and hemorrhage was associated with CD reclassification. Different from the other two groups, IBDU exhibited a more acute onset and a gradual progression. When an IBD patient presents with transmural inflammation or crypt abscess but lacks transmural lymphoid aggregates or fissuring ulcers, the diagnosis of IBDU should be considered.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Ubiquitous Colonic Ileal Metaplasia Consistent with the Diagnosis of Crohn's Colitis among Indeterminate Colitis Cohorts

Background

Inadequate differentiated diagnostic features of predominantly colonic inflammatory bowel diseases i.e., ulcerative colitis and Crohn's colitis, may lead to inexact diagnosis of "indeterminate colitis". About 15% of indeterminate colitis patients are diagnosed at colonoscopy, in colonic biopsies, and/or at colectomy. Managing outcomes of indeterminate colitis, given its unpredictable clinical presentation, depends on future diagnosis of colitis, Crohn's colitis or ulcerative colitis.

Objective

Overview the diagnostic efficacy of ectopic colonic ileal metaplasia and human α-defens 5 (DEFA5 alias HD5) for accurate delineation of indeterminate colitis into authentic Crohn's colitis and/ or ulcerative colitis.

Design

We describe a targeted protein for potentially differentiating indeterminate colitis into an accurate clinical subtype diagnosis of inflammatory bowel diseases i.e., ulcerative colitis and Crohn's colitis.

Patients

Twenty-one patients with the clinically inexact diagnosis of indeterminate colitis were followed, reassessed and data analyzed.

Main outcome measures

We observed that (i) some patients had their original diagnosis changed from indeterminate colitis to either ulcerative colitis or Crohn's colitis; and (ii) human α-defensin 5 is aberrantly overexpressed in Crohn's colitis.

Results

Fifteen of the twenty-one (71.4%) patients with indeterminate colitis had their inconclusive diagnosis changed; nine patients changed to ulcerative colitis and six to Crohn's colitis. In human colon surgical samples, Human α-defensin-5 was significantly upregulated in Crohn's colitis. In addition, Human α-defensin 5 processing enzyme, matrix metalloptotease-7 was inversely expressed compared to Human α- Defensin 5.

Limitation

Due to the sequence homology of the α-defensin class of proteins, preceding efforts to raise antibodies (Abs) against DEFA5 have limitations to produce adequate specificity. The Abs used in previous assays recognizes the α-defensins, active α-defensins 5 and inactive pro- α-defensins 5. Monoclonal antibodies (mAbs) to determine specificity and sensitivity of α-defensins 5, which is diagnostic of CC disease, and NOT other α-defensins is the limitation to overcome.

Conclusion

It is feasible to differentiate ulcerative colitis from Crohn's colitis among patients with inexact diagnosis of indeterminate colitis using Human α-defensin 5 as a molecular biosignature delineator.

Inflammatory Bowel Disease-Associated Colorectal Cancer: Translational and Transformational Risks Posed by Exogenous Free Hemoglobin Alpha Chain, A By-Product of Extravasated Erythrocyte Macrophage Erythrophagocytosis

Colonic inflammatory bowel disease (IBD) encompasses ulcerative colitis (UC) and Crohn's colitis (CC). Patients with IBD are at increased risk for colitis-associated colorectal cancer (CACRC) compared to the general population. CACRC is preceded by IBD, characterized by highly heterogenous, pharmacologically incurable, pertinacious, worsening, and immune-mediated inflammatory pathologies of the colon and rectum. The molecular and immunological basis of CACRC is highly correlated with the duration and severity of inflammation, which is influenced by the exogenous free hemoglobin alpha chain (HbαC), a byproduct of infiltrating immune cells; extravasated erythrocytes; and macrophage erythrophagocytosis. The exogenous free HbαC prompts oxygen free radical-arbitrated DNA damage (DNAD) through increased cellular reactive oxygen species (ROS), which is exacerbated by decreased tissue antioxidant defenses. Mitigation of the Fenton Reaction via pharmaceutical therapy would attenuate ROS, promote apoptosis and DNAD repair, and subsequently prevent the incidence of CACRC. Three pharmaceutical options that attenuate hemoglobin toxicity include haptoglobin, deferoxamine, and flavonoids (vitamins C/E). Haptoglobin's clearance rate from plasma is inversely correlated with its size; the smaller the size, the faster the clearance. Thus, the administration of Hp1-1 may prove to be beneficial. Further, deferoxamine's hydrophilic structure limits its ability to cross cell membranes. Finally, the effectiveness of flavonoids, natural herb antioxidants, is associated with the high reactivity of hydroxyl substituents. Multiple analyses are currently underway to assess the clinical context of CACRC and outline the molecular basis of HbαC-induced ROS pathogenesis by exposing colonocytes and/or colonoids to HbαC. The molecular immunopathogenesis pathways of CACRC herein reviewed are broadly still not well understood. Therefore, this timely review outlines the molecular and immunological basis of disease pathogenesis and pharmaceutical intervention as a protective measure for CACRC.

Histologic Diagnosis of Inflammatory Bowel Diseases

Inflammatory bowel disease, including ulcerative colitis and Crohn disease, is an idiopathic chronic inflammatory condition of the gastrointestinal tract. Since neither the clinical manifestations nor the morphologic features of inflammatory bowel disease are pathognomonic alone, the differential diagnosis to consider is relatively broad, and it relies on the synthesis of clinical, endoscopic, and microscopic features. Long-held histologic diagnostic principles include recognizing structural and inflammatory features of chronicity, that is, architectural distortion, basal plasmacytosis, and expansion of the lamina propria lymphoplasmacytic infiltrate. In addition, evaluation of the neutrophilic inflammation and related crypt and epithelial destruction is essential to gauge the activity of the disease. Nevertheless, these features can be difficult to confirm in special settings, including at the inception of the disease or in partially treated cases. This review will explore the classic morphologic features of ulcerative colitis and Crohn disease, followed by a detailed discussion of atypical and diagnostically challenging presentations and a brief review of the clinical aspects necessary for the daily practice of pathologists.

Intestinal Ultrasonography as a Tool for Monitoring Disease Activity in Patients with Ulcerative Colitis

BACKGROUND

Ultrasonography is a noninvasive, inexpensive, and widely available diagnostic tool. In the last two decades, the development of ultrasound techniques and equipment has significantly increased the usage of intestine ultrasound (US) in the assessment of the gastrointestinal tract in patients with inflammatory bowel disease (IBD). Although current guidelines suggest routine utilization of US in patients with Crohn's disease, data regarding US usage in ulcerative colitis are still scarce. We aimed to assess the reliability of intestinal ultrasonography in the assessment of disease activity and extension of patients with ulcerative colitis.

METHODS

Fifty-five patients with a histologically confirmed diagnosis of ulcerative colitis, treated at University Clinical Center of Serbia in the period from 2019 to 2022 were included in this retrospective observational study. The data were obtained from the patient's medical records including history, laboratory, US, and endoscopy findings. US examined parameters were as following: bowel wall thickness (BWT), presence of fat wrapping, wall layer stratification, mesenteric hypertrophy, presence of enlarged mesenteric lymph nodes, and absence or presence of ascites.

RESULTS

Our results suggest that there is a strong correlation of BWT and colonoscopy findings regarding disease extension (r = 0.524, p=0.01, p < 0.05). Furthermore, our results have shown a statistically significant correlation of BWT with the Mayo endoscopic score (r = 0.434, p=0.01, p < 0.05), disease activity score (r = 0.369,p=0.01, p < 0.05), degree of ulcerative colitis burden of luminal inflammation (r = 0.366, p=0.01, p < 0.05), and Geboes index (r = 0.298, p=0.027, p < 0.05). Overall accuracy of US for disease extension and activity was statistically significant (p < 0.05).

CONCLUSIONS

Our results suggest that US is a moderately accurate method for the assessment of disease activity and localization in patients with UC.

Staged Approaches to Restorative Proctocolectomy with Ileoanal Pouch-When and Why?

Restorative proctocolectomy (RPC) with ileal pouch anal-anastomosis (IPAA) is commonly performed for patients with ulcerative colitis, familial adenomatous polyposis, and selected phenotypes of Crohn's disease (CD). Due to concerns about the effects of surgical complications on pouch functional outcomes, debate remains surrounding when and whether RPC with IPAA should be performed in a staged manner. Particularly debated are the timings of the IPAA, whether it is constructed at time of the proctocolectomy and whether to utilize temporary fecal diversion with a loop ileostomy. RPC with IPAA can be performed in one, two, or three stages, with each stage typically separated by 3-6 months. Proponents of a staged approach argue that poor pouch function, which is often a result of IPAA complications, including leak and infection, can be difficult to overcome and mandate additional, major surgeries, and that staging pouch creation and pairing with a protective ileostomy reduce those complications. However, subjecting patients to multiple surgeries and prolonging their time with an ileostomy present unique risks as well. Surgeons' experience and preference and patient characteristics need to be considered when determining operative planning. Highly selected patients with CD can be considered for RPC with IPAA, although with an acknowledgment of inherently higher pouch failure rates. Understanding the short- and long-term consequences of RPC with IPAA construction can help surgeons determine the appropriate approach.

Postoperative diagnostic revision for Crohn disease after subtotal colectomy for inflammatory bowel disease

PURPOSE

Subtotal colectomy (STC) is performed for severe acute and refractory colitis. The diagnosis can be difficult even after the surgery when colectomy specimen has overlapping features of ulcerative colitis (UC) and Crohn's disease (CD). The aim of this study was to evaluate the rate of postoperative diagnostic revision to CD after surgery and determine predictor factors.

METHODS

Retrospective study of 110 patients who underwent STC (2005-2018).

RESULTS

Preoperative diagnosis comprised UC = 80 (73%), CD = 11 (10%), and unclassified colitis (IBDU = 19, 17%). Initial diagnosis of IBDU and UC was modified to CD in 6 patients (6%) after STC. The final diagnosis after the follow-up of 10 ± 6 years switched from CD for 8 patients (9%). The multivariate analysis showed that patients with a colitis evolving for less than 10 years and initial diagnosis of IBDU were the two independent factors associated with an increased risk of diagnosis change to CD (p = 0.03; p = 0.016). At the end of the follow-up, 15 patients (14%) had a definitive stoma.

CONCLUSIONS

In patients with IBD, attention must be paid to determine the right restorative strategy to patients with an evolution of the disease less than 10 years or with IBDU who are more at risk to have a diagnosis change to CD after STC.

Indeterminate Colitis - Update on Treatment Options

Indeterminate colitis (IC) is described in approximately 5-15% of patients with inflammatory bowel disease (IBD). It usually reflects a difficulty or lack of clarity in distinguishing between ulcerative colitis (UC) and Crohn's disease (CD) on biopsy or colectomy specimens. The diagnostic difficulty may explain the variability in the reported prevalence and incidence of IC. Clinically, most IC patients tend to evolve over time to a definite diagnosis of either UC or CD. IC has also been interchangeably described as inflammatory bowel disease unclassified (IBDU). This review offers an overview of the available limited literature on the conventional medical and surgical treatments for IC. In contrast to the numerous studies on the medical management of UC and CD, there are very few data from dedicated controlled trials on the treatment of IC. The natural evolution of IC more closely mimics UC. Regarding medical options for treatment, most patients diagnosed with IC are treated similarly to UC, and treatment choices are based on disease severity. Others are managed similarly to CD if there are features suggestive of CD, including fissures, skin tags, or rectal sparing. In medically refractory IC, surgical treatment options are limited and include total proctocolectomy (TPC) and ileal pouch-anal anastomosis (IPAA), with its associated risk factors and complications. Post-surgical complications and pouch failure rates were historically thought to be more common in IC patients, but recent meta-analyses reveal similar rates between UC and IC patients. Future therapies in IBD are focused on known mechanisms in the disease pathways of UC and CD. Owing to the lack of IC-specific studies, clinicians have traditionally and historically extrapolated the data to IC patients based on their symptomatology, clinical course, and endoscopic findings.

Outcome of Ileal Pouch-anal Anastomosis in Patients With Indeterminate Colitis: A Systematic Review and Meta-analysis

BACKGROUND

Indeterminate colitis [IC] is type of inflammatory bowel disease that exhibits features of both ulcerative colitis [UC] and Crohn's disease [CD]. The present meta-analysis aimed to assess the outcomes of ileal pouch-anal anastomosis [IPAA] in patients with IC in comparison with patients with UC.

METHODS

A PRISMA-compliant systematic review of the outcome of IPAA in patients with IC was conducted. Electronic databases were searched, and full-text articles were reviewed to extract essential data. Main outcome measures were pouch failure and pouch-related complications.

RESULTS

A total of 17 studies were included in this meta-analysis. There were 1057 patients with IC and 6511 patients with UC. The weighted mean pouch failure rate in patients with IC was 7.5 (95% confidence interval [CI]: 4.8-10.2) and the weighted mean complication rate was 67 [95% CI: 53.5-80.5]. As compared with patients with UC, patients with IC had significantly higher odds of developing complications after IPAA (odds ratio [OR]: 2.6, p <0.001): pouch fistula [OR:4.98, p <0.001], pelvic sepsis [OR:3.98, p =0.002], pelvic or cuff abscess [OR: 4.5, p <0.001], perineal complications [OR: 5.13, p <0.001], and ultimate diagnosis of CD [OR: 2.57, p <0.001]. Patients with IC and UC had similar odds of pouch failure, pouchitis, anastomotic leak, stricture, and small bowel obstruction.

CONCLUSIONS

Patients with IC had similar pouch failure rates, yet higher overall complication rates than patients with UC. Complications that tend to be higher after IPAA for patients with IC include pouch fistula, pelvic sepsis, abscess, perineal complications, and ultimate diagnosis of Crohn's disease.

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.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

An Overview of Inflammatory Bowel Disease Unclassified in Children

Background

The inflammatory bowel diseases cover a diverse range of conditions generally grouped into Crohn's disease (CD) or ulcerative colitis (UC) based on clinical, laboratory, radiological, endoscopic, and histological criteria. However, inflammatory bowel disease unclassified (IBDU) is used when there are clinical and endoscopic signs of chronic colitis without specific features of UC or CD but features of both. Conjecture exists regarding IBDU, especially in children, as to whether it represents a unique childhood phenotype or whether it reflects the difficulties in assigning an IBD subtype at an early age.

Summary

This review examines the current understanding of pediatric IBDU and assesses the evidence supporting IBDU as a distinctive disease entity on the spectrum of inflammatory bowel disease.

Key Messages

Pediatric-onset IBDU is more common than adult-onset IBDU. Therefore, an understanding of IBDU in this age group assumes more importance. However, there remains a paucity of information and a lack of exclusive longitudinal studies on pediatric IBDU. Subsequently there is significant disparity in the reported prevalence, clinical course, reclassification trends, and treatment responses around pediatric IBDU. Therefore, it remains challenging to chart the natural history of pediatric IBDU and consequently form an accurate understanding of where pediatric IBDU sits on the spectrum of disease.

The Human Mesenteric Lymph Node Microbiome Differentiates Between Crohn's Disease and Ulcerative Colitis

BACKGROUND AND AIMS

Mesenteric lymph nodes are sites in which translocated bacteria incite and progress immunological responses. For this reason, understanding the microbiome of mesenteric lymph nodes in inflammatory bowel disease is important. The bacterial profile of Crohn's disease mesenteric lymph nodes has been analysed using culture-independent methods in only one previous study. This study aimed to investigate the mesenteric lymph node microbiota from both Crohn's disease and ulcerative colitis patients.

METHODS

Mesenteric lymph nodes were collected from Crohn's disease and ulcerative colitis patients undergoing resection. Total DNA was extracted from mesenteric lymph nodes and assessed for the presence of bacterial DNA [16S]. All work was completed in a sterile environment using aseptic techniques. Samples positive for 16S DNA underwent next-generation sequencing, and the identity of bacterial phyla and species were determined.

RESULTS

Crohn's disease mesenteric lymph nodes had a distinctly different microbial profile to that observed in ulcerative colitis. The relative abundance of Firmicutes was greater in nodes from ulcerative colitis patients, whereas Proteobacteria were more abundant in Crohn's disease. Although species diversity was reduced in the mesenteric lymph nodes of patients with Crohn's disease, these lymph nodes contained greater numbers of less dominant phyla, mainly Fusobacteria.

CONCLUSION

This study confirms that there are distinct differences between the Crohn's disease and ulcerative colitis mesenteric lymph node microbiomes. Such microbial differences could aid in the diagnosis of Crohn's disease or ulcerative colitis, particularly in cases of indeterminate colitis at time of resection, or help explain their mechanisms of development and progression.

Colonic Crohn's Disease Is Associated with Less Aggressive Disease Course Than Ileal or Ileocolonic Disease

BACKGROUND

The literature on disease characteristics of colonic Crohn's disease (CD) is sparse, especially from Asia, where the burden of inflammatory bowel disease is on the rise. The present study aims to describe the disease characteristics of colonic CD, and compare it with that of ileal/ileocolonic disease.

METHODS

This retrospective study included adult patients of CD (diagnosed by standard criteria, follow-up duration > 6 months) on follow-up between August 2004 and January 2016. The disease location was classified by Montreal classification. The data were recorded on demographic characteristics, smoking status, disease phenotype, disease course, treatment received, hospitalization and surgeries.

RESULTS

Of 406 CD patients, 123 had colonic [mean age (at onset) 30.4 ± 13.2 years, 59.3% males] and 265 had ileal/ileocolonic disease [mean age (at onset) 32.9 ± 13.8 years, 61.5% males] while 18 patients had isolated upper GI disease. The frequency of inflammatory behavior (B1 phenotype; 61.8 vs. 46.4%, p = 0.003), perianal disease (23.6 vs. 4.5%, p < 0.001), and extra-intestinal manifestation (42.3 vs. 30.2%, p = 0.019) was higher in colonic than ileal/ileocolonic CD. Though not statistically significant, requirement of atleast one course of steroid was lower in colonic CD (72.7 vs. 84.2%, p = 0.098). Although there was no difference in the frequency of hospitalization (30.1 vs. 27.1%, p = 0.45), the overall requirement for surgery was significantly lower in colonic CD (17.1 vs. 26.1%, p = 0.032) and patients with colonic disease had a lower cumulative probability of first surgery in the first 10 years of follow-up [Hazard ratio 0.556 (95% CI 0.313-0.985), p = 0.045].

CONCLUSION

Colonic CD was associated with less aggressive disease behavior and lower requirement of surgery as compared to ileal/ileocolonic CD.

How Secure Is the Diagnosis of Ulcerative Colitis in Children, Even After Colectomy?

OBJECTIVES

We reviewed all children who have undergone a colectomy for ulcerative colitis (UC) in our tertiary referral centre in a 12-year period to assess the rate of reclassification as Crohn disease (CD). In contrast to CD, a colectomy is considered to be definitive treatment for patients with UC. Distinguishing between the 2 can be challenging when disease is manifest only within the colon-even histological examination of a colectomy specimen may be inconclusive. Historically, the recognised "rediagnosis" rate (post-colectomy) was reported at approximately 3% to 7%. A recent study suggested that a higher rate of 13% should be expected in children. This has implications in terms of pre-operative counselling and surgical decision making.

METHODS

A retrospective case-note review of all patients who underwent a colectomy for UC between 2003 and 2014 in a single paediatric tertiary referral centre was performed.

RESULTS

Of the 570 children diagnosed with inflammatory bowel disease in this period, 190 were diagnosed as UC. Of these 190 cases, 29 underwent a colectomy. None of these was re-classified following histological examination of the colectomy sample. Seven out of the 29 patients (24%) were subsequently diagnosed with CD (median follow-up 7.6 years). This is significantly higher than previously reported rates (P = 0.003).

CONCLUSIONS

Our data suggest that later manifestation of CD is more common than previously thought (24%). Therefore, a diagnosis of UC in children should be regarded as provisional and a potential later diagnosis of CD taken into account when considering colectomy and J-pouch formation.

[Differential indications for ileoanal pouch anastomosis : Ulcerative colitis, familial adenomatous polyposis, synchronous colorectal cancer - Crohn's disease, constipation]

Ileoanal pouch anastomosis is the procedure of choice for patients with drug refractory ulcerative colitis, indeterminate colitis and familial adenomatous polyposis (FAP). In selected patient groups this procedure is a treatment option for patients with Crohn's disease, hereditary nonpolyposis colorectal cancer (HNPCC), synchronous colorectal cancer and for severe colorectal constipation refractory to conservative drug treatment. The pouch procedure provides the opportunity to avoid a permanent ileostomy. The majority of surgeons prefer the ileal J‑pouch as the construction is the easiest to perform and complications and dysfunction rates are low. Due to functional reasons most pouch surgeons favor a circular stapled ileoanal pouch anastomosis. The more radical proctocolectomy can produce sensory defects in the anal canal with subsequent soiling and incontinence. Studies have shown that even after proctocolectomy residual rectal mucosa was found in the anal canal. Therefore, the functionally important anorectal transitional zone should be preserved if possible. Ulcerative colitis can be "healed" with proctocolectomy; however, pouchitis can still occur in one third of the patients. Patients must be informed about the risk of pouchitis and a multidisciplinary monitoring and treatment strategy must be available. In Crohn's disease the ileoanal pouch survival rate of 80% in the long-term follow-up is surprisingly good despite an increased postoperative complication rate. The anal pouch anastomosis is the standard operation in patients with drug refractory ulcerative colitis, indeterminate colitis and FAP. Synchronous colorectal cancer, HNPCC and severe therapy refractive constipation represent rare indications for proctocolectomy where decisions must be made on an individual basis.

Recent advances in clinical practice: a systematic review of isolated colonic Crohn's disease: the third IBD?

The genetics of isolated colonic Crohn's disease place it approximately midway between Crohn's disease with small intestinal involvement and UC, making a case for considering it as a separate condition. We have therefore systematically reviewed its epidemiology, pathophysiology and treatment. Key findings include a higher incidence in females (65%) and older average age at presentation than Crohn's disease at other sites, a mucosa-associated microbiota between that found in ileal Crohn's disease and UC, no response to mesalazine, but possibly better response to antitumour necrosis factor than Crohn's disease at other sites. Diagnostic distinction from UC is often difficult and also needs to exclude other conditions including ischaemic colitis, segmental colitis associated with diverticular disease and tuberculosis. Future studies, particularly clinical trials, but also historical cohorts, should assess isolated colonic Crohn's disease separately.

Essential role of small bowel capsule endoscopy in reclassification of colonic inflammatory bowel disease type unclassified

AIM

To evaluate the role of small bowel capsule endoscopy (SBCE) on the reclassification of colonic inflammatory bowel disease type unclassified (IBDU).

METHODS

We performed a multicenter, retrospective study including patients with IBDU undergoing SBCE, between 2002 and 2014. SBCE studies were reviewed and the inflammatory activity was evaluated by determining the Lewis score (LS). Inflammatory activity was considered significant and consistent with Crohn’s disease (CD) when the LS ≥ 135. The definitive diagnosis during follow-up (minimum 12 mo following SBCE) was based on the combination of clinical, analytical, imaging, endoscopic and histological elements.

RESULTS

Thirty-six patients were included, 21 females (58%) with mean age at diagnosis of 33 ± 13 (15-64) years. The mean follow-up time after the SBCE was 52 ± 41 (12-156) mo. The SBCE revealed findings consistent with significant inflammatory activity in the small bowel (LS ≥ 135) in 9 patients (25%); in all of them the diagnosis of CD was confirmed during follow-up. In 27 patients (75%), the SBCE revealed no significant inflammatory activity (LS < 135); among these patients, the diagnosis of Ulcerative Colitis (UC) was established in 16 cases (59.3%), CD in 1 case (3.7%) and 10 patients (37%) maintained a diagnosis of IBDU during follow-up. A LS ≥ 135 at SBCE had a sensitivity = 90%, specificity = 100%, positive predictive value = 100% and negative predictive value = 94% for the diagnosis of CD.

CONCLUSION

SBCE proved to be fundamental in the reclassification of patients with IBDU. Absence of significant inflammatory activity in the small intestine allowed exclusion of CD in 94% of cases.

Long-Term Outcomes in Indeterminate Colitis Patients Undergoing Ileal Pouch-Anal Anastomosis: Function, Quality of Life, and Complications

INTRODUCTION

It is uncertain whether the outcomes of patients with indeterminate colitis (IC) undergoing ileal pouch-anal anastomosis (IPAA) deteriorate over time. The aim of this study was to determine the long-term pouch function, quality of life, complications, and incidence of Crohn's disease after IPAA for patients with IC compared to ulcerative colitis (UC).

METHODS

A case matched analysis was performed on patients undergoing IPAA for pathologically confirmed IC or UC, between 1985 and 2014. Patients were case matched for age ± 5 years, gender, date of surgery ± 3 years, type of anastomosis and presence of a diverting loop ileostomy. All patients were followed up for greater than six months.

RESULTS

448 patients were case matched, the average age was 36.8 year old and 52.7 % of patients were male. Mean follow-up was 122.06 months (+/- 80.77 months). There were statistically and clinically comparable number of daytime bowel movements (5.7 v 5.5, p = 0.45), rates of incontinence (26.1 % v 18.3 %, p = 0.09) and nighttime seepage in patients (23.1 % v 28.4 %, p = 0.28) with IC and UC. Quality of life markers and patient restrictions were comparable between the two groups. Rates of pelvic sepsis (IC 8.5 %, UC 8.5 %, p = 0.99) and anastomotic leak (IC 3.1 %, UC 4.0 %, p = 0.61) were similar but fistula formation (IC 15.6 %, UC 8.0 %, p = 0.01) and IPAA Crohn's disease rates (IC 6.7 %, UC 2.7 %, p = 0.04) were significantly increased in IC patients. There was no statistically significant difference in pouch failure rates for IC and UC (5.8 % vs.4.9 %, p = 0.58).

CONCLUSION

Patients undergoing IPAA for IC have a higher risk of post-operative fistulae and development of Crohn's disease, but comparable morbidity, functional outcomes, quality of life scores and pouch failure rates when compared to UC patients. Long-term data confirms that IPAA is a good surgical option in patients with IC.

Human alpha defensin 5 is a candidate biomarker to delineate inflammatory bowel disease

Inability to distinguish Crohn's colitis from ulcerative colitis leads to the diagnosis of indeterminate colitis. This greatly effects medical and surgical care of the patient because treatments for the two diseases vary. Approximately 30 percent of inflammatory bowel disease patients cannot be accurately diagnosed, increasing their risk of inappropriate treatment. We sought to determine whether transcriptomic patterns could be used to develop diagnostic biomarker(s) to delineate inflammatory bowel disease more accurately. Four patients groups were assessed via whole-transcriptome microarray, qPCR, Western blot, and immunohistochemistry for differential expression of Human α-Defensin-5. In addition, immunohistochemistry for Paneth cells and Lysozyme, a Paneth cell marker, was also performed. Aberrant expression of Human α-Defensin-5 levels using transcript, Western blot, and immunohistochemistry staining levels was significantly upregulated in Crohn's colitis, p< 0.0001. Among patients with indeterminate colitis, Human α-Defensin-5 is a reliable differentiator with a positive predictive value of 96 percent. We also observed abundant ectopic crypt Paneth cells in all colectomy tissue samples of Crohn's colitis patients. In a retrospective study, we show that Human α-Defensin-5 could be used in indeterminate colitis patients to determine if they have either ulcerative colitis (low levels of Human α-Defensin-5) or Crohn's colitis (high levels of Human α-Defensin-5). Twenty of 67 patients (30 percent) who underwent restorative proctocolectomy for definitive ulcerative colitis were clinically changed to de novo Crohn's disease. These patients were profiled by Human α-Defensin-5 immunohistochemistry. All patients tested strongly positive. In addition, we observed by both hematoxylin and eosin and Lysozyme staining, a large number of ectopic Paneth cells in the colonic crypt of Crohn's colitis patient samples. Our experiments are the first to show that Human α-Defensin-5 is a potential candidate biomarker to molecularly differentiate Crohn's colitis from ulcerative colitis, to our knowledge. These data give us both a potential diagnostic marker in Human α-Defensin-5 and insight to develop future mechanistic studies to better understand crypt biology in Crohn's colitis.

Emerging Biomarkers for the Diagnosis and Monitoring of Inflammatory Bowel Diseases

There is currently no single test available to confidently diagnose cases of inflammatory bowel disease (IBD). Physicians rely on a number of diagnostic tools, including clinical evaluation, serum testing, and imaging, which are used on conjunction with endoscopic evaluation. It is often difficult to determine whether patients with abdominal pain and change in bowel habit have functional bowel symptoms or whether they have a true diagnosis of IBD. Even once a diagnosis of IBD has been made, a significant proportion of patients are labeled with the term "indeterminate colitis" where histological sampling cannot confidently subclassify patients as either Crohn's or ulcerative colitis. Colonoscopy is an inconvenient and uncomfortable test for most patients. In addition, it is not without serious risks of perforation, as well as risks which can be associated with sedation and analgesia given during the procedure. The use of biomarkers to aid in the diagnosis, subclassification, and monitoring of IBD is an ever expanding area. In this review, we have concentrated on noninvasive biomarkers of IBD, because these are more acceptable to patients and easier to perform in everyday clinical practice. We will first touch on those biomarkers currently well established and in wide clinical use, such as C-reactive protein, erythrocyte sedimentation rate. Faecal calprotectin and their use in the diagnosis of IBD. Following on, we will review more novel biomarkers and their use in subclassification and monitoring of IBD, including a variety of antibodies, genetics, and microRNAs, as well as touching on metabolomics.

The role of small bowel capsule endoscopy and ileocolonoscopy in patients with nonspecific but suggestive symptoms of Crohn's disease

OBJECTIVES

Ileocolonoscopy (IC) and small bowel capsule endoscopy (SBCE) are essential tools in the investigation of suspected small bowel Crohn's disease (CD). Overutilization of SBCE should be avoided as it leads to unwanted healthcare expenses; thus, it is recommended when IC is normal and CD is still highly suspected. Our aim was to compare the role of SBCE and IC in the investigation of suspected CD irrespective of its location and assess the additional diagnostic benefit of SBCE over IC.

METHODS

This was a retrospective study of 91 patients with chronic abdominal pain and/or diarrhea. All patients were evaluated with both colonoscopy (with terminal ileum intubation where possible) and SBCE. The severity of inflammation on SBCE was assessed using the Lewis Score. Endoscopic findings were analyzed toward CD diagnosis.

RESULTS

The sensitivity of IC and SBCE in the diagnosis of either small bowel or colonic CD was 81.82 and 63.64%, whereas the specificity was 77.50 and 92.50%, respectively. Positive and negative predictive value was 33.33 and 96.88% for IC, as well as 53.85 and 94.87% for SBCE. Area under receiver operating characteristic curve was 0.797 for IC and 0.781 for SBCE. IC was superior to SBCE in diagnosing small and large bowel CD. SBCE showed the true extent of CD in one patient missed by IC. It identified lesions suggestive of CD in three patients with normal IC, one of whom was finally diagnosed with CD.

CONCLUSION

IC should be the initial diagnostic test in patients with nonspecific, but suggestive symptoms of CD. SBCE offers additional information on small bowel mucosa and disease extent.

Particularities of Crohn's disease in pediatric patients: current status and perspectives regarding imaging modalities

A consensus on the best imaging modality evaluating inflammatory bowel disease in the pediatric population is lacking and it is often unclear which modality to choose in specific clinical circumstances. Children with inflammatory bowel disease are exposed to ionizing radiation from multiple imaging studies performed at initial diagnosis, throughout treatment and during the follow-up period. This paper discusses the value of different imaging techniques in pediatric patients with inflammatory bowel disease and gives a review of the literature. In addition, particular features of inflammatory bowel disease in children including the predilection of affected segments in the gastrointestinal tract are highlighted. Based on current literature knowledge, we encourage an integrative approach to the interpretation of clinical and imaging data for diagnosis and follow-up in daily clinical settings.

Crohn's Disease of the Ileoanal Pouch

Crohn's disease (CD) of the pouch is an increasingly recognized diagnosis after ileal pouch-anal anastomosis. This post-ileal pouch-anal anastomosis diagnosis in conjunction with pouchitis remains the leading reason for pouch excision. Unfortunately, CD of the pouch remains a difficult diagnosis with lack of a uniform definition largely because of its similarity to common postoperative pouch complications, including pouchitis, abscess formation, or stricture at the anastomosis. Once diagnosed, treatment algorithms largely include multimodal therapy including biologics. This review focuses on the definition, etiology, diagnosis, and treatment for CD of the pouch, a postoperative de novo diagnosis of CD.

Outpatient management of inflammatory bowel disease

Inflammatory bowel disease is a conglomeration of disorders of unclear etiology and pathogenesis. Confirming the diagnosis of active disease may be difficult but is critical to judicious therapy. Sulfasalazine (Azulfidine) and its newer derivatives mesalamine (Asacol, Rowasa) and olsalazine sodium (Dipentum) are used for treatment of mild disease and maintenance. Corticosteroid therapy controls moderate disease in most patients, but withdrawal may be difficult. Immunosuppression or surgery may be necessary in severe or refractory cases. The risk of cancer as a complication of inflammatory bowel disease is often exaggerated but cannot be ignored.

Current application of proteomics in biomarker discovery for inflammatory bowel disease

Recently, the field of proteomics has rapidly expanded in its application towards clinical research with objectives ranging from elucidating disease pathogenesis to discovering clinical biomarkers. As proteins govern and/or reflect underlying cellular processes, the study of proteomics provides an attractive avenue for research as it allows for the rapid identification of protein profiles in a biological sample. Inflammatory bowel disease (IBD) encompasses several heterogeneous and chronic conditions of the gastrointestinal tract. Proteomic technology provides a powerful means of addressing major challenges in IBD today, especially for identifying biomarkers to improve its diagnosis and management. This review will examine the current state of IBD proteomics research and its use in biomarker research. Furthermore, we also discuss the challenges of translating proteomic research into clinically relevant tools. The potential application of this growing field is enormous and is likely to provide significant insights towards improving our future understanding and management of IBD.

Pregnancy and inflammatory bowel diseases: Current perspectives, risks and patient management

Inflammatory bowel diseases (IBD) are chronic idiopathic inflammatory conditions characterized by relapsing and remitting episodes of inflammation which can affect several different regions of the gastrointestinal tract, but also shows extra-intestinal manifestations. IBD is most frequently diagnosed during peak female reproductive years, with 25% of women with IBD conceiving after their diagnosis. While IBD therapy has improved dramatically with enhanced surveillance and more abundant and powerful treatment options, IBD disease can have important effects on pregnancy and presents several challenges for maintaining optimal outcomes for mothers with IBD and the developing fetus/neonate. Women with IBD, the medical team treating them (both gastroenterologists and obstetricians/gynecologists) must often make highly complicated choices regarding conception, pregnancy, and post-natal care (particularly breastfeeding) related to their choice of treatment options at different phases of pregnancy as well as post-partum. This current review discusses current concerns and recommendations for pregnancy during IBD and is intended for gastroenterologists, general practitioners and IBD patients intending to become, (or already) pregnant, and their families. We have addressed patterns of IBD inheritance, effects of IBD on fertility and conception (in both men and women), the effects of IBD disease activity on maintenance of pregnancy and outcomes, risks of diagnostic procedures during pregnancy and potential risks and complications associated with different classes of IBD therapeutics. We also have evaluated the clinical experience using "top-down" care with biologics, which is currently the standard care at our institution. Post-partum care and breastfeeding recommendations are also addressed.

Gastrointestinal endoscopy biopsy derived proteomic patterns predict indeterminate colitis into ulcerative colitis and Crohn’s colitis

Patients with indeterminate colitis (IC) are significantly younger at diagnosis with onset of symptoms before the age of 18 years with significant morbidity in the interim. The successful care of IC is based on microscopic visual predict precision of eventual ulcerative colitis (UC) or Crohn’s colitis (CC) which is not offered in 15%-30% of inflammatory bowel disease (IBD) patients even after a combined state-of-the-art classification system of clinical, visual endoscopic, radiologic and histologic examination. These figures have not changed over the past 3 decades despite the introduction of newer diagnostic modalities. The patient outcomes after restorative proctocolectomy and ileal pouch-anal anastomosis may be painstaking if IC turns into CC. Our approach is aiming at developing a single sensitive and absolute accurate diagnostic test tool during the first clinic visit through endoscopic biopsy derived proteomic patterns. Matrix-assisted-laser desorption/ionization mass spectrometry (MS) and/or imaging MS technologies permit a histology-directed cellular test of endoscopy biopsy which identifies phenotype specific proteins, as biomarker that would assist clinicians more accurately delineate IC as being either a UC or CC or a non-IBD condition. These novel studies are underway on larger cohorts and are highly innovative with significances in differentiating a UC from CC in patients with IC and could lend mechanistic insights into IBD pathogenesis.

A contemporary and critical appraisal of 'indeterminate colitis'

Distinguishing ulcerative colitis (UC) from Crohn's disease (CD) is normally based on evaluation of a variety of clinical, radiologic, serologic and pathologic findings, the latter in biopsy and/or resection specimens. Unfortunately, some patients with IBD show overlapping pathologic features of UC and CD, which makes definite distinction between these two disorders difficult or even impossible. In most instances of uncertainty, the patient shows clinical and pathologic features of UC, but in addition, the patient's colon resection specimen reveals one or more CD-like features. In this setting, a diagnosis of indeterminate colitis (IC) is often rendered. IC is not a distinct disease entity, and, thus, it has no diagnostic criteria. The most common causes of uncertainty in IBD pathology that may lead to a diagnosis of IC in a colon resection specimen includes the presence of fulminant (severe and toxic) colitis, insufficient radiologic, endoscopic, or pathologic information (including analysis of prior biopsies) on the patient, failure to utilize major diagnostic criteria as hard evidence in favor of CD, failure to recognize unusual variants of UC and CD that may mimic each other, failure to recognize non-IBD mimics and other superimposed diseases that cause unusual pathologic features in a resection specimen, an attempt to distinguish UC from CD in mucosal biopsies of the colon and ileum, or an attempt to change the patients diagnosis (of UC or CD) based on pouch or diversion-related complications. Details of each of these causes of uncertainty are discussed, in detail, in this review article. A diagnosis of IC should never be made clinically or by pathologists based on evaluation of pre-resection colonic mucosal biopsies. Ultimately, the majority of indeterminate cases represent UC, and, thus, most of these patient can be treated safely with a colectomy combined with an ileal pouch anal anastomosis procedure.

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.

Identification of pathologic features associated with “ulcerative colitis-like” Crohn’s disease

AIM: To identify pathologic features associated with this “ulcerative colitis (UC)-like” subgroup of Crohn’s disease (CD).

METHODS: Seventeen subjects diagnosed as having UC who underwent proctocolectomy (RPC) from 2003-2007 and subsequently developed CD of the ileal pouch were identified. UC was diagnosed based on pre-operative clinical, endoscopic, and pathologic studies. Eighteen patients who underwent RPC for UC within the same time period without subsequently developing CD were randomly selected and used as controls. Pathology reports and histological slides were reviewed for a wide range of gross and microscopic pathological features, as well as extent of disease. The demographics, gross description and histopathology of the resection specimens were reviewed and compared between the two groups.

RESULTS: Patients with “UC-like” CD were on average 13 years younger than those with “true” UC (P < 0.01). More severe disease in the proximal involved region and active ileitis with/without architectural distortion were observed in 6 of 17 (35%) and 7 of 17 (41%) “UC-like” CD cases, respectively, but in none of the “true” UC cases (P < 0.05). Active appendicitis occurred in 8 of 16 (50%) “UC-like” CD cases but in only two (11%) “true” UC cases (P < 0.05). Conspicuous lamina propria neutrophils were more specific for “UC-like” CD (76% vs 22%, P < 0.05). In addition, prominent lymphoid aggregates tended to be more common in “UC-like” CD (P = 0.07). The “true” UC group contained a greater number of cases with severe activity (78% vs 47%). Therefore, the features more commonly seen in “UC-like” CD were not due to a more severe disease process. Crohn’s granulomas and transmural inflammation in non-ulcerated areas were absent in both groups.

CONCLUSION: More severe disease in the proximal involved region, terminal ileum involvement, active appendicitis, and prominent lamina propria neutrophils may be morphological factors associated with “UC-like” CD.

A novel gas chromatography mass spectrometry-based serum diagnostic and assessment approach to ulcerative colitis

BACKGROUND & AIMS

To improve the clinical course of ulcerative colitis (UC), more accurate serum diagnostic and assessment methods are required. We used serum metabolomics to develop diagnostic and assessment methods for UC.

METHODS

Sera from UC patients, Crohn's disease (CD) patients, and healthy volunteers (HV) were collected at multiple institutions. The UC and HV were randomly allocated to the training or validation set, and their serum metabolites were analyzed by gas chromatography mass spectrometry (GC/MS). Using the training set, diagnostic and assessment models for UC were established by multiple logistic regression analysis. Then, the models were assessed using the validation set. Additionally, to establish a diagnostic model for discriminating UC from CD, the CD patients' data were used.

RESULTS

The diagnostic model for discriminating UC from HV demonstrated an AUC of 0.988, 93.33% sensitivity, and 95.00% specificity in the training set and 95.00% sensitivity and 98.33% specificity in the validation set. Another model for discriminating UC from CD exhibited an AUC of 0.965, 85.00% sensitivity, and 97.44% specificity in the training set and 83.33% sensitivity in the validation set. The model for assessing UC showed an AUC of 0.967, 84.62% sensitivity, and 88.23% specificity in the training set and 84.62% sensitivity, 91.18% specificity, and a significant correlation with the clinical activity index (rs=0.7371, P<0.0001) in the validation set.

CONCLUSIONS

Our models demonstrated high performance and might lead to the development of a novel treatment selection method based on UC condition.

Histological evaluation in ulcerative colitis

This review summarizes diagnostic problems, challenges and advances in ulcerative colitis (UC). It emphasizes that, although histopathological examination plays a major role in the diagnosis and management of UC, it should always be interpreted in the context of clinical, endoscopic, and radiological findings. Accurate diagnosis requires knowledge of the classic morphological features of UC, as well as a number of atypical pathological presentations that may cause mis-classification of the disease process, either in resection or biopsy specimens. These atypical pathological presentations include rectal sparing and patchiness of disease at initial presentation of UC in pediatric patients or in the setting of medically treated UC, cecal or ascending colon inflammation in left-sided UC, and backwash ileitis in patients with severe ulcerative pancolitis. Loosely formed microgranulomas, with pale foamy histiocytes adjacent to a damaged crypt or eroded surface, should not be interpreted as evidence of Crohn's disease. Indeterminate colitis should only be used in colectomy specimens as a provisional pathological diagnosis. Patients with UC are at risk for the development of dysplasia and carcinoma; optimal outcomes in UC surveillance programs require familiarity with the diagnostic criteria and challenges relating to UC-associated dysplasia and malignancy. Colon biopsy from UC patients should always be evaluated for dysplasia based on cytological and architectural abnormalities. Accurate interpretation and classification of dysplasia in colon biopsy from UC patients as sporadic adenoma or UC-related dysplasia [flat, adenoma-like, or dysplasia-associated lesion or mass (DALM)] requires clinical and endoscopic correlation. Isolated polypoid dysplastic lesions are considered to be sporadic adenoma if occurring outside areas of histologically proven colitis, or adenoma-like dysplasia if occurring in the diseased segment. Recent data suggest that such lesions may be treated adequately by polypectomy in the absence of flat dysplasia in the patient. UC patients with DALM or flat high-grade dysplasia should be treated by colectomy because of the high probability of adenocarcinoma. The natural history of low-grade dysplasia (LGD) is more controversial: while multifocal LGD, particularly if detected at the time of initial endoscopic examination, is treated with colectomy, unifocal flat LGD detected during surveillance may be managed by close follow-up with increased surveillance. The surveillance interval and treatment options for UC patients with dysplasia are reviewed in detail.

Elastic scattering spectroscopy as an optical marker of inflammatory bowel disease activity and subtypes

BACKGROUND

In 10% to 15% of individuals, inflammatory bowel disease (IBD) is difficult to classify as ulcerative colitis (UC) or Crohn's disease (CD). Previous work has demonstrated that probe-based elastic scattering spectroscopy (ESS) can produce spectra, informed by parameters like tissue ultrastructure and hemoglobin content, capable of differentiating pathologies. This study investigates whether ESS is an in vivo optical biomarker for the presence, activity, and type of IBD in the colon.

METHODS

Pilot study, a retrospective data analysis. ESS spectra of endoscopically normal and inflamed colon were obtained from 48 patients with IBD and 46 non-IBD controls. Measurements from patients with IBD were categorized as CD or UC based on clinical diagnosis. Spectra were analyzed using high-dimensional methods. Leave-one-patient-out cross-validation was used to obtain diagnostic performance estimates.

RESULTS

Patients with IBD were distinguishable from non-IBD controls with a sensitivity of 0.93 and specificity of 0.91 based on readings from endoscopically normal mucosa, and 0.94 and 0.93 from inflamed mucosa. In patients with IBD, histologically normal and inflamed colon were distinguishable with per-class accuracies of 0.83 and 0.89, respectively; histologically normal from inactive inflammation with accuracies of 0.73 and 0.89, respectively; and inactive from active colitis with accuracies of 0.87 and 0.84, respectively. The diagnosis of CD versus UC was made with per-class accuracies of 0.92 and 0.87 in normal and 0.87 and 0.85 in inflamed mucosa, respectively.

CONCLUSIONS

ESS, a simple, low-cost clinically friendly optical biopsy modality, has the potential to enhance the endoscopic assessment of IBD and its activity in real time and may help to distinguish CD from UC.

Characteristics of inflammatory bowel disease serology in patients with indeterminate colitis

GOALS AND BACKGROUND

Inflammatory bowel disease (IBD) serology testing is often used in patients with indeterminate colitis (IC) to help distinguish between ulcerative colitis (UC) and Crohn's disease (CD). We investigated the performance of serology testing in predicting future diagnosis in this setting.

STUDY

This was an observational study of individuals with IC at a single center who underwent IBD serology testing [anti-Saccharomyces cerevisiae antibody (ASCA), perinuclear anti-neutrophil cytoplasmic antibody (pANCA), and anti-outer membrane porin C antibody (anti-OmpC)] and had at least 12 months follow-up from the time of serology test results.

RESULTS

A total of 117 individuals with IC and with 1-year follow-up data were enrolled. All IC patients had endoscopic and histologic evidence of colitis at enrollment. One year after serology testing, 58 (50%) individuals with IC were diagnosed with UC, 49 (42%) with CD, and 10 (9%) remained labeled with IC. The sensitivity/specificity of an initial positive pANCA for a subsequent diagnosis of UC was 78%/44%. For ASCA and anti-OmpC, the results were 18%/84% and 27%/75%, respectively, for a subsequent diagnosis of CD. A positive pANCA test was associated with a likelihood ratio (LR) of 1.4 [95% confidence interval (CI), 1.1-1.8] for a subsequent diagnosis of UC at 1 year. Neither positive ASCA (LR 1.1; 95% CI, 0.5-2.5) nor anti-OmpC (LR 1.1; 95% CI, 0.6-2.0) was associated with a subsequent diagnosis of CD in patients with IC.

CONCLUSIONS

The disease phenotype in the majority of individuals initially labeled with IC evolved to be more consistent with either UC or CD on follow-up. pANCA, ASCA, and anti-OmpC, individually, were of limited utility in predicting a patient's subsequent disease phenotype.

Ulcerative colitis or Crohn's disease? Pitfalls and problems

The interpretation of colorectal biopsies taken for the initial diagnosis of chronic idiopathic inflammatory bowel disease (IBD) is challenging. Subclassification of IBD as ulcerative colitis (UC) or Crohn's disease, which may be particularly difficult, is the subject of this review. Biopsies taken at first presentation are emphasised, partly because their features have not been modified by time or treatment. Aspects of longstanding disease and of resections are also mentioned. The first part of the review comprises background considerations and a summary of histological features that are discriminant, according to published evidence, between UC and Crohn's disease in initial biopsies. Pitfalls and problems associated with making the distinction between UC and Crohn's disease are then discussed. These include: mimics of IBD; inadequate clinical details; unreliable microscopic features; absence of histological changes in early IBD; discontinuity in UC; cryptolytic granulomas; differences between paediatric and adult UC; reliance on ileal and oesophagogastroduodenal histology; and atypical features in IBD resections. Avoidance by pathologists of known pitfalls should increase the likelihood of accurate and confident subclassification of IBD, which is important for optimum medical and surgical management.

European consensus on the histopathology of inflammatory bowel disease

The histologic examination of endoscopic biopsies or resection specimens remains a key step in the work-up of affected inflammatory bowel disease (IBD) patients and can be used for diagnosis and differential diagnosis, particularly in the differentiation of UC from CD and other non-IBD related colitides. The introduction of new treatment strategies in inflammatory bowel disease (IBD) interfering with the patients' immune system may result in mucosal healing, making the pathologists aware of the impact of treatment upon diagnostic features. The European Crohn's and Colitis Organisation (ECCO) and the European Society of Pathology (ESP) jointly elaborated a consensus to establish standards for histopathology diagnosis in IBD. The consensus endeavors to address: (i) procedures required for a proper diagnosis, (ii) features which can be used for the analysis of endoscopic biopsies, (iii) features which can be used for the analysis of surgical samples, (iv) criteria for diagnosis and differential diagnosis, and (v) special situations including those inherent to therapy. Questions that were addressed include: how many features should be present for a firm diagnosis? What is the role of histology in patient management, including search for dysplasia? Which features if any, can be used for assessment of disease activity? The statements and general recommendations of this consensus are based on the highest level of evidence available, but significant gaps remain in certain areas.

Inflammatory bowel disease biopsies: updated British Society of Gastroenterology reporting guidelines

Accurate histopathological assessment of biopsies is important for the diagnosis, subclassification, and management of chronic idiopathic inflammatory bowel disease (IBD). British Society of Gastroenterology (BSG) guidelines for the initial histopathological diagnosis of IBD were published in 1997. Changes since then include: more widespread use of full colonoscopy; greater recognition of the effects of time and treatment; improved documentation of variations in anatomical distribution; better understanding of the mimics of IBD; significant progress in clinical management; and modifications of terminology. Accordingly, an update is required. These revised guidelines aim to optimise the quality and consistency of reporting of biopsies taken for the initial diagnosis of IBD by summarising the literature and making recommendations based on the available evidence. Advice from existing clinical guidelines is also taken into account. Among the subjects discussed are: distinguishing IBD from other colitides, particularly infective colitis; subclassification of IBD (as ulcerative colitis, Crohn's disease, or IBD unclassified); the discriminant value of granulomas; aspects of disease distribution, including discontinuity in ulcerative colitis; time-related changes; differences between paediatric and adult IBD; the role of ileal and upper gastrointestinal biopsies; differential diagnoses such as diverticular colitis and diversion proctocolitis; and dysplasia. The need to correlate the histological features with clinical and endoscopic findings is emphasised. An approach to the conclusion of an IBD biopsy report based on the acronym Pattern, Activity, Interpretation, Dysplasia (PAID) is suggested. The key recommendations are listed at the end of the document.

Urinary NMR metabolomic profiles discriminate inflammatory bowel disease from healthy

BACKGROUND AND AIMS

Inflammatory bowel disease, a chronic inflammation of the intestinal tract, presents in two variations, Ulcerative Colitis (UC) and Crohn's disease (CD). Given that treatment of CD differs from UC, a single test that provided strong diagnostic ability would offer great clinical value. Two previous studies have indicated that CD can be distinguished from UC, and that both can be distinguished from non-IBD-type gastrointestinal disease, based on urinary and faecal metabolite profiling.

METHODS

Analysis of healthy as well as CD and UC patients attending an IBD clinic was performed. IBD patients were classified into two groups (CD or UC) based on chart review of clinical, endoscopic, and histological assessment. Urine samples were obtained and analyzed using nuclear magnetic resonance (NMR) spectroscopy combined with targeted profiling techniques, followed by univariate and multivariate statistical analysis.

RESULTS

Based on urinary metabolomics, individuals with IBD could be differentiated from healthy. Major differences between IBD and healthy included TCA cycle intermediates, amino acids, and gut microflora metabolites. Comparison of CD and UC patients revealed discrimination, but removal of patients with the surgical intervention confounder revealed that CD could not be discriminated from UC.

CONCLUSIONS

This study highlights the potential for metabolomics to distinguish IBD from the healthy state but shows that careful consideration must be given to establishing disease-representative cohorts that are free of confounding factors.