Inflammatory bowel disease

Causal association of blood cell traits with inflammatory bowel diseases: a Mendelian randomization study

Background

Observational studies have found associations between blood cell traits and inflammatory bowel diseases (IBDs), whereas the causality and dose-effect relationships are still undetermined.

Methods

Two-sample Mendelian randomization (MR) analyses using linear regression approaches, as well as Bayesian model averaging (MR-BMA), were conducted to identify and prioritize the causal blood cell traits for Crohn's disease (CD) and ulcerative colitis (UC). An observational study was also performed using restricted cubic spline (RCS) to explore the relationship between important blood cell traits and IBDs.

Results

Our uvMR analysis using the random effects inverse variance weighted (IVW) method identified eosinophil (EOS) as a causal factor for UC (OR = 1.36; 95% CI: 1.13, 1.63). Our MR-BMA analysis further prioritized that high level of lymphocyte (LYM) decreased CD risk (MIP = 0.307; θ ^ MACE = -0.059; PP = 0.189; θ ^ λ = -0.173), whereas high level of EOS increased UC risk (MIP = 0.824; θ ^ MACE = 0.198; PP = 0.627; θ ^ λ = 0.239). Furthermore, the observational study clearly depicts the nonlinear relationship between important blood cell traits and the risk of IBDs.

Conclusion

Using MR approaches, several blood cell traits were identified as risk factors of CD and UC, which could be used as potential targets for the management of IBDs. Stratified genome-wide association studies (GWASs) based on the concentration of traits would be helpful owing to the nonlinear relationships between blood cell traits and IBDs, as demonstrated in our clinical observational study. Together, these findings could shed light on the clinical strategies applied to the management of CD and UC.

Role of Hydrogen Sulfide in Inflammatory Bowel Disease

Hydrogen sulfide (H2S), originally known as toxic gas, has now attracted attention as one of the gasotransmitters involved in many reactions in the human body. H2S has been assumed to play a role in the pathogenesis of many chronic diseases, of which the exact pathogenesis remains unknown. One of them is inflammatory bowel disease (IBD), a chronic intestinal disease subclassified as Crohn's disease (CD) and ulcerative colitis (UC). Any change in the amount of H2S seems to be linked to inflammation in this illness. These changes can be brought about by alterations in the microbiota, in the endogenous metabolism of H2S and in the diet. As both too little and too much H2S drive inflammation, a balanced level is needed for intestinal health. The aim of this review is to summarize the available literature published until June 2023 in order to provide an overview of the current knowledge of the connection between H2S and IBD.

Possible Impact of Vitamin D Status and Supplementation on SARS-CoV-2 Infection Risk and COVID-19 Symptoms in a Cohort of Patients with Inflammatory Bowel Disease

The coronavirus disease (COVID-19) pandemic represents a global health challenge, particularly considering concomitant diseases. Patients with inflammatory bowel diseases (IBD) can be considered a population at risk. On the other hand, the risk of developing IBD and COVID-19 have both been described as modulated by vitamin D (VD) levels. In this work, a cohort of 106 adult patients affected by IBD was prospectively enrolled, during the second wave of the pandemic in Italy. In these patients, VD plasma levels, demographic, and clinical characteristics were tested for a correlation/an association with the risk of infection with SARS-CoV-2 in the study period (anti-spike IgG positivity) and the severity of COVID-19 symptoms. By multivariate logistic regression analysis, VD supplementation (Odds Ratio; OR 0.116, p = 0.002), therapy with monoclonal antibodies (OR 0.227, p = 0.007), and the use of mesalazine (OR 2.968, p = 0.046) were found to be independent predictors of SARS-CoV-2 positivity. Moreover, hypertension was associated with severe disease (p = 0.019), while a VD level higher than 30 ng/mL (p = 0.031, OR 0.078) was associated with asymptomatic infection. No interplay between IBD activity and COVID-19 risk of infection or symptoms was observed. These results confirm the importance of VD levels in defining the risk of COVID-19 and give encouraging data about the safety of maintaining immunomodulatory treatments for IBD during the COVID-19 pandemic.

Gut Microbiota, Probiotic Interventions, and Cognitive Function in the Elderly: A Review of Current Knowledge

Changes in the composition and proportions of the gut microbiota may be associated with numerous diseases, including cognitive impairment. Over the recent years, the growing interest in this relation is observed, but there are still many unknowns, especially in the elderly. To the best of our knowledge, this is the first work that synthesizes and critically evaluates existing evidence on the possible association between human gut microbiota and cognitive function in the elderly. For this purpose, comprehensive literature searches were conducted using the electronic databases PubMed, Google Scholar, and ScienceDirect. The gut microbiota of cognitively healthy and impaired elderly people may differ in the diversity and abundance of individual taxes, but specific taxes cannot be identified. However, some tendencies to changing the Firmicutes/Bacteroidetes ratio can be identified. Currently, clinical trials involving probiotics, prebiotics, and synbiotics supplementation have shown that there are premises for the claim that these factors can improve cognitive functions, however there is no single intervention beneficial to the elderly population. More reliable evidence from large-scale, long-period RCT is needed. Despite proposing several potential mechanisms of the gut microbiota's influence on the cognitive function impairment, prospective research on this topic is extremely difficult to conduct due to numerous confounding factors that may affect the gut microbiota. Heterogeneity of research outcomes impairs insight into these relations.

The Role of Cyclophilins in Inflammatory Bowel Disease and Colorectal Cancer

Cyclophilins (Cyps) is a kind of ubiquitous protein family in organisms, which has biological functions such as promoting intracellular protein folding and participating in the pathological processes of inflammation and tumor. Inflammatory bowel disease (IBD) and colorectal cancer (CRC) are two common intestinal diseases, but the etiology and pathogenesis of these two diseases are still unclear. IBD and CRC are closely associated, IBD has always been considered as one of the main risks of CRC. However, the role of Cyps in these two related intestinal diseases is rarely studied and reported. In this review, the expression of CypA, CypB and CypD in IBD, especially ulcerative colitis (UC), and CRC, their relationship with the development of these two intestinal diseases, as well as the possible pathogenesis, were briefly summarized, so as to provide modest reference for clinical researches and treatments in future.

Disease-associated reference intervals for twenty laboratory tests in patients with rheumatoid arthritis, Crohn's disease or ulcerative colitis

BACKGROUND

Population based reference intervals are fundamental for interpreting results for quantitative laboratory tests. In patients with a specific chronic disorder, however, results of various tests may regularly be different than in healthy individuals. Health-associated reference intervals may therefore have limited value in such patients. Instead, disease-associated reference intervals may be useful, as they describe the results distribution in populations resembling the specific patients. Few disease-associated reference intervals are available in the literature. The aim of this study was to estimate reference intervals for common laboratory tests for patient populations with rheumatoid arthritis, Crohn's disease or ulcerative colitis without significant comorbidity, using a novel algorithm.

MATERIAL AND METHODS

Laboratory test results and hospital discharge diagnoses were collected for relevant patients. An algorithm was developed to identify discharge diagnoses significantly associated with high or low results for specific tests. After excluding patients with such diagnoses, reference intervals were estimated, representing results distributions in patients with each of the specific chronic disorders, but without significant comorbidity.

RESULTS

Disease-associated reference intervals were estimated for 20 common laboratory tests. Most of the estimated reference limits were significantly different from corresponding health-associated reference limits. Thirty percent of the estimated reference intervals were different from estimates based on crude patient populations, indicating that the algorithm applied managed to exclude patients with relevant comorbidity.

CONCLUSION

Disease-associated reference intervals could be estimated for a number of tests in patients with rheumatoid arthritis, ulcerative colitis or Crohn's disease using a highly automated algorithm based on routinely recorded patient data.

Inflammatory bowel disease: tri-directional relationship between microbiota, immune system and intestinal epithelium

Human gut microbiota contributes to host nutrition and metabolism, sustains intestinal cell proliferation and differentiation, and modulates host immune system. The alterations in their composition lead to severe gut disorders, including inflammatory bowel disease (IBD) or inflammatory bowel syndrome (IBS). IBD including ulcerative colitis (UC) and Crohn's disease (CD) are gamut of chronic inflammatory disorders of gut, mediated by complex interrelations among genetic, environmental, and internal factors. IBD has debateable aetiology, however in recent years, exploring the central role of a tri-directional relationship between gut microbiota, mucosal immune system, and intestinal epithelium in pathogenesis is getting the most attention. Increasing incidences and early onset explains the exponential rise in IBD burden on health-care systems. Industrialization, hypersensitivity to allergens, lifestyle, hygiene hypothesis, loss of intestinal worms, and gut microbial composition, explains this shifted rise. Hitherto, the interventions modulating gut microbiota composition, microfluidics-based in vitro gastrointestinal models, non-allergic functional foods, nutraceuticals, and faecal microbiota transplantation (FMT) from healthy donors are some of the futuristic approaches for the disease management.

IL-1 and CD40/CD40L platelet complex: elements of induction of Crohn's disease and new therapeutic targets

Ulcerative colitis (UC) and Crohn's disease (CD) are chronic and multifactorial diseases that affect the intestinal tract, both characterized by recurrent inflammation of the intestinal mucosa, resulting in abdominal pain, diarrhea, vomiting and, rectal bleeding. Inflammatory bowel diseases (IBD) regroup these two disorders. The exact pathological mechanism of IBD remains ambiguous and poorly known. In genetically predisposed patients, defects in intestinal mucosal barrier are due to an uncontrolled inflammatory response to normal flora. In addition to the genetic predisposition, these defects could be triggered by environmental factors or by a specific lifestyle which is widely accepted as etiological hypothesis. The involvement of the CD40/CD40L platelet complex in the development of IBD has been overwhelmingly demonstrated. CD40L is climacteric in cell signalling in innate and adaptive immunity, the CD40L expression on the platelet cell surface gives them an immunological competence. The IL-1, a major inflammation mediator could be involved in different ways in the development of IBD. Here, we provide a comprehensive review regarding the role of platelet CD40/CD40L in the pathophysiological effect of IL-1 in the development of Crohn's disease (CD). This review could potentially help future approaches aiming to target these two pathways for therapeutic purposes and elucidate the immunological mechanisms driving gut inflammation.

Clinical diagnosis and endoscopic analysis of 10 cases of intestinal tuberculosis

To analyze the clinical characteristics of intestinal tuberculosis (ITB), pay attention to the diagnostic value of endoscopy and mucosal biopsy, improve the recognition of atypical manifestations of ITB under endoscopy, and reduce misdiagnosis and missed diagnosis.The clinical data of 10 patients who were hospitalized in Changzhou second people's Hospital and finally diagnosed as ITB from January 1, 2015 to present were analyzed retrospectively. The basic information, medical history, clinical manifestations and computed tomography (CT), endoscopy of the patients was analyzed retrospectively. The results of pathological examination were analyzed and sorted out.Among the 10 patients, the ratio of male to female was 7:3, 10 (100%) had abdominal pain, 3 (30%) had diarrhea and 2 (20%) had bloody stool. The positive rate of tuberculosis T cell test was 75% (6/8), the diagnostic rate of chest high resolution CT was 60%, and the abnormal rate of abdominal high-resolution CT was 66.7% (6/9). Colonoscopy showed that the lesions mainly involved ileocecum (70%) and ascending colon (60%). Most of the lesions were intestinal stenosis (60%) and circular ulcer (50%). In a few cases, cold abscess (20%) and scar diverticulum (10%). Most of the pathological manifestations were granuloma formation and multinucleated giant cells (60%). The detection rate of caseous granuloma was 20%.The general condition and clinical manifestations of patients with ITB are not specific. Endoscopy and mucosal biopsy are of great significance for its diagnosis. The clinical manifestations and endoscopy of some patients showed atypical signs. Therefore, the combination of multi-disciplinary team models and the enhancement of clinician's recognition of the characteristics of endoscopic examination of ITB can improve us the diagnosis level of ITB.

Inflammatory Bowel Disease Presentation and Diagnosis

A full understanding of the presentation and work-up of inflammatory bowel disease is necessary to ensure appropriate treatment of this complex disease. Crohn's disease and ulcerative colitis share many common clinical features but are treated very differently. This article covers the factors which contribute to IBD pathogenesis and presentation as well as the methods of diagnosis and work-up to ensure that the appropriate diagnosis is reached. This article also serves as a basis of understanding for the more complex aspects of the disease to be discussed in subsequent articles.

Analysis of Phenotypic Variables and Differentiation Between Untypical Crohn's Disease and Untypical Intestinal Tuberculosis

BACKGROUND

The differentiation between untypical intestinal tuberculosis (UITB) and untypical Crohn's disease (UCD) is a challenge.

AIMS

To analyze phenotypic variables and propose a novel prediction model for differential diagnosis of two conditions.

METHODS

A total of 192 patients were prospectively enrolled. The clinical, laboratory, endoscopic, and radiological features were investigated and subjected to univariable and multivariable analyses. The final prediction model for differentiation between UCD and UITB was developed by logistic regression analysis and Fisher discriminant analysis on the training set. The same discriminant function was tested on the validation set.

RESULTS

Twenty-five candidates were selected from 52 phenotypic variables of typical Crohn's disease (TCD), UCD, and UITB patients. UCD's variables overlapped with both TCD and UITB. The percentages of tuberculosis history, positive PPD, and positive T-SPOT result in UCD were all significantly higher than that in TCD (11.6% vs. 0.0%, 27.9% vs. 0.0%, 25.6% vs. 4.5%, respectively, P < 0.05). The regression equations and Fisher discriminant function for discrimination between UCD and UITB were developed. In the training data, the area under the receiver operating characteristic of equations was 0.834, 0.69, and 0.648 in the clinical-laboratory, endoscopic, and radiological model, respectively. The accuracy of Fisher discriminant function for discrimination was 86% in UCD and 73% in UITB in the validation data.

CONCLUSIONS

Phenotypes of UCD patients in TB-endemic countries may be associated with TB infection history. Fisher discriminant analysis is a good choice to differentiate UCD from UITB, which is worthy of verification in clinical practice.

Docosapentaenoic acid (DPA, 22:5n-3) ameliorates inflammation in an ulcerative colitis model

DPA showed an anti-inflammatory profile by competing with AA to decrease the synthesis of pro-inflammatory eicosanoids (LTB₄ and PGE₂).

Diagnostic Markers for Nonspecific Inflammatory Bowel Diseases

The nonspecific inflammatory bowel diseases (IBD) represent a heterogeneous group of chronic inflammatory disorders of the gastrointestinal tract, and Leśniowski-Crohn's disease (CD) and ulcerative colitis (UC) are among the two major clinical forms. Despite the great progress in understanding the pathogenesis of these diseases, their etiology remains unclear. Genetic, immune, and environmental factors are thought to play a key role. The correct diagnosis of nonspecific inflammatory bowel diseases as well as the determination of disease activity, risk stratification, and prediction of response to therapy still relies on a multidisciplinary approach based on clinical, laboratory, endoscopic, and histologic examination. However, considerable effort has been devoted to the development of an accurate panel of noninvasive biomarkers that have increased diagnostic sensitivity and specificity. Laboratory biomarkers useful in differentiating IBD with functional disorders and in evaluating disease activity, prognosis, and treatment selection for IBD are presented in this study.

Inflammatory Bowel Diseases: Review of Known Environmental Protective and Risk Factors Involved

Inflammatory bowel diseases consisting of Crohn's disease and ulcerative colitis are chronic inflammatory diseases of the gastrointestinal tract. In addition to genetic susceptibility and disturbances of the microbiome, environmental exposures forming the exposome play an important role. Starting at birth, the cumulative effect of different environmental exposures combined with a predetermined genetic susceptibility is thought to cause inflammatory bowel disease. All these environmental factors are part of a Western lifestyle, suiting the high incidence rates in Europe and the United States. Whereas receiving breastfeeding, evidence of a Helicobacter pylori infection and vitamin D are important protective factors in Crohn's disease as well as ulcerative colitis, increased hygiene, experiencing a bacterial gastroenteritis in the past, urban living surroundings, air pollution, the use of antibiotics, nonsteroidal anti-inflammatory drugs, and oral contraceptives are likely to be the most important risk factors for both diseases. Current cigarette smoking yields a divergent effect by protecting against ulcerative colitis but increasing risk of Crohn's disease, whereas former smoking increases chances of both diseases. This review gives a clear overview of the current state of knowledge concerning the exposome. Future studies should focus on measuring this exposome yielding the possibility of combining all involved factors to one exposome risk score and our knowledge on genetic susceptibility.

Preoperative Nutritional Conditioning of Crohn's Patients-Systematic Review of Current Evidence and Practice

Crohn’s disease is an incurable and frequently progressive entity with major impact on affected patients. Up to half of patients require surgery in the first 10 years after diagnosis and over 75% of operated patients require at least one further surgery within lifetime. In order to minimize surgical risk, modifiable risk factors such as nutritional status need to be optimized. This systematic review on preoperative nutritional support in adult Crohn’s patients between 1997 and 2017 aimed to provide an overview on target populations, screening modalities, routes of administration, and expected benefits. Pertinent study characteristics (prospective vs. retrospective, sample size, control group, limitations) were defined a priori. Twenty-nine studies were retained, of which 14 original studies (9 retrospective, 4 prospective, and 1 randomized controlled trial) and 15 reviews. Study heterogeneity was high regarding nutritional regimens and outcome, and meta-analysis could not be performed. Most studies were conducted without matched control group and thus provide modest level of evidence. Consistently, malnutrition was found to be a major risk factor for postoperative complications, and both enteral and parenteral routes were efficient in decreasing postoperative morbidity. Current guidelines for nutrition in general surgery apply also to Crohn’s patients. The route of administration should be chosen according to disease presentation and patients’ condition. Further studies are needed to strengthen the evidence.

A Fixed Stricture on Routine Cross-sectional Imaging Predicts Disease-Related Complications and Adverse Outcomes in Patients with Crohn's Disease

BACKGROUND

Patients with Crohn's disease (CD) typically undergo multiple cross-sectional imaging exams including computed tomography and magnetic resonance enterography during the course of their disease. The aim was to identify imaging findings that predict future disease-related poor outcomes.

METHODS

This was a retrospective, case control study at a single tertiary center. Cases were CD patients diagnosed with complications (bowel obstruction, perforation, internal fistula, or abscess); controls were CD patients without complications. Two radiologists blinded to clinical outcomes, independently scored cross-sectional imaging examinations obtained before the complication.

RESULTS

One hundred eight patients (67 F; 41 M) with CD (51 cases; 57 controls) were included. For the cases, 21 had internal fistulae, 15 had bowel obstructions, 13 had abdominal abscesses, and 2 developed bowel perforations. Patients with complications were more likely to have a fixed small bowel stricture on cross-sectional imaging (P = 0.01). A patient with a stricture and upstream dilatation was 3.4 times more likely to develop a complication in the next 2 years. When present in the setting of hypervascularity and/or evidence of active inflammation, the risk increased further to 15-fold. Cases were more likely to be active smokers (29% versus 12%, P = 0.033). Cases had more evidence of inflammation based on higher Harvey Bradshaw Index values and inflammatory biomarkers and lower hemoglobin values.

CONCLUSIONS

Information from radiologic studies, especially the presence of fixed strictures, can predict future CD complications. These findings, along with smoking and ongoing inflammation, should alert the clinician to the possibility of future complications.

Tolerance Limits, Self-understanding, and Stress Resilience in Integrative Recovery of Inflammatory Bowel Disease

People living with chronic inflammatory bowel disease (IBD) experienced that knowledge about their embodied tolerance limits, diet, mental problem solving, and change in lifestyle together with integrative health care could promote recovery from their diagnosed disease in calmer periods of suffering. A hermeneutic approach was used to analyze interviews with patients living with IBD outside hospitals. Thirteen young adults between 18 and 45 years of age in calmer phases of IBD participated in the study. Three main themes emerged from the analysis of the interviews: (1) Understanding limits in embodied tolerance, (2) Restoring balance is creating a new equilibrium, and (3) Creating resilience through integrative care. Anxiety, depression, stress, insomnia, and fatigue are known consequences of IBD and create a lower degree of well-being for the patients. The digestive system is very important in establishing the interface between the body and the external world. Properly functioning digestion, psychosocial stress reduction, and sleep quality are important to rebuild a balanced immune system. Stress resilience during a patient's recovery from IBD requires self-understanding, self-recognition, and psychosocial support from health care professionals at hospital outpatient clinics.

Increasing Incidence of Crohn's Disease with Familial Clustering in the Kingdom of Bahrain: A 25-Year Population-based Study

BACKGROUND

The incidence of Crohn's disease has been increasing in developed countries; whether this trend has extended to countries in Middle East, especially in the Arab world, remains unclear. Our aim was to study the epidemiology, incidence, time trends and clustering of Crohn's disease within the population of the Kingdom of Bahrain.

METHODS

A retrospective case-cohort study was conducted on patients diagnosed with Crohn's disease at Bahrain Specialist Hospital between 1990 and 2015. The diagnosis was based on clinical, radiological, endoscopic, and histological examinations.

RESULTS

Five hundred twenty-two cases were eligible for analysis; 14.5% were below the age of 19 with a male-to-female ratio of 1.1:1. The overall incidence was 4.8/100,000 person-years and significantly increased from 5.5/100,000 person-years during the 1990's to 8.0/100,000 person-years during the last study period [incidence rate ratio (IRR) 0.32, 95% CI = 0.26-0.42]. This trend was persistent for adults, children, men and women. There were 129 patients with at least one family member diagnosed with Crohn's disease consisting of 40 families. Three clusters were identified based on first or second degree relationship of the family member. The mean interval for diagnosis between family members was significantly shorter between siblings than second degree relatives; (2.0 ± 1.2 years) versus (5.0 ± 2.8 years), respectively; (P = 0.04).

CONCLUSIONS

The incidence rate of Crohn's disease in Bahrain is comparable to the U.S.A and has increased for men and women in all age groups. Crohn's disease clusters were common among families and included up to 3 generations consistent with presence of a common source or common genetic factors.