Mucosal immunology, eosinophilic esophagitis, and other intestinal inflammatory diseases

An efficient computational framework for gastrointestinal disorder prediction using attention-based transfer learning

Diagnosing gastrointestinal (GI) disorders, which affect parts of the digestive system such as the stomach and intestines, can be difficult even for experienced gastroenterologists due to the variety of ways these conditions present. Early diagnosis is critical for successful treatment, but the review process is time-consuming and labor-intensive. Computer-aided diagnostic (CAD) methods provide a solution by automating diagnosis, saving time, reducing workload, and lowering the likelihood of missing critical signs. In recent years, machine learning and deep learning approaches have been used to develop many CAD systems to address this issue. However, existing systems need to be improved for better safety and reliability on larger datasets before they can be used in medical diagnostics. In our study, we developed an effective CAD system for classifying eight types of GI images by combining transfer learning with an attention mechanism. Our experimental results show that ConvNeXt is an effective pre-trained network for feature extraction, and ConvNeXt+Attention (our proposed method) is a robust CAD system that outperforms other cutting-edge approaches. Our proposed method had an area under the receiver operating characteristic curve of 0.9997 and an area under the precision-recall curve of 0.9973, indicating excellent performance. The conclusion regarding the effectiveness of the system was also supported by the values of other evaluation metrics.

The Clinical Characteristics and Treatment Outcomes of Concomitant Eosinophilic Esophagitis and Inflammatory Bowel Disease

Background

The clinical characteristics and treatment outcomes in patients with eosinophilic esophagitis (EoE) and inflammatory bowel disease (IBD) have not been extensively investigated.

Methods

We determined treatment outcomes and frequencies of disease-related complications in patients with EoE and IBD.

Results

Among 69 patients who met inclusion criteria, 39 (56.5%) had a diagnosis of Crohn disease. Clinical and histologic response rates to proton pump inhibitors and topical steroids were 25.9% and 24.4%, respectively.

Conclusions

Lower than expected clinical and histologic response rates for EoE suggest the combination of EoE and IBD is a medically refractory phenotype with more difficult to treat EoE.

Outer Membrane Vesicles Derived from Klebsiella pneumoniae Influence the miRNA Expression Profile in Human Bronchial Epithelial BEAS-2B Cells

Klebsiella pneumoniae is an opportunistic pathogen that causes nosocomial and community-acquired infections. The spread of resistant strains of K. pneumoniae represents a growing threat to human health, due to the exhaustion of effective treatments. K. pneumoniae releases outer membrane vesicles (OMVs). OMVs are a vehicle for the transport of virulence factors to host cells, causing cell injury. Previous studies have shown changes of gene expression in human bronchial epithelial cells after treatment with K. pneumoniae OMVs. These variations in gene expression could be regulated through microRNAs (miRNAs), which participate in several biological mechanisms. Thereafter, miRNA expression profiles in human bronchial epithelial cells were evaluated during infection with standard and clinical K. pneumoniae strains. Microarray analysis and RT-qPCR identified the dysregulation of miR-223, hsa-miR-21, hsa-miR-25 and hsa-let-7g miRNA sequences. Target gene prediction revealed the essential role of these miRNAs in the regulation of host immune responses involving NF-ĸB (miR-223), TLR4 (hsa-miR-21), cytokine (hsa-miR-25) and IL-6 (hsa-let-7g miRNA) signalling pathways. The current study provides the first large scale expression profile of miRNAs from lung cells and predicted gene targets, following exposure to K. pneumoniae OMVs. Our results suggest the importance of OMVs in the inflammatory response.

Recent insights on the use of topical steroids in eosinophilic esophagitis

INTRODUCTION

Eosinophilic Esophagitis (EoE) is an immune-mediated, chronic inflammatory disorder of the esophagus. Topical steroids have been used in the management of EoE for over 15 years. However, there are no Food and Drug Administration (FDA) approved drug therapies for EoE.

AREAS COVERED

This review discusses the current understanding of EoE and the role of topical steroids in the induction and maintenance of remission in patients with EoE. We performed a comprehensive review of the literature, summarized randomized control trials from 2006 to 2020, and provided a simplified management algorithm for EoE.

EXPERT OPINION

In patients with EoE, topical steroids are effective in inducing clinical and histologic remission. Formulations of topical steroids that maximize the exposure to esophageal mucosa have the highest efficacy. A majority of patients who achieve remission with topical steroids develop clinical and histologic relapse off therapy within a year. Current evidence suggests that maintenance therapy with long-term topical steroids decreases the risk of relapse and progression to fibrostenotic disease. While uncertainty over the dose and duration of maintenance topical steroids and their potential side effects exists, long-term maintenance therapy with topical steroids appears to be the way forward to improve long-term outcomes in patients with EoE.

Biologic Therapy in Crohn's Disease-What We Have Learnt So Far

Crohn's disease (CD) is an autoimmune disorder from the group of inflammatory bowel diseases. The etiology of CD is not clear; currently, the interaction between the genetic, immunological and environmental factors is assumed as the cause of the disease. Partial knowledge of those factors has led to the development of drugs, which control the clinical symptoms and improve the overall condition of the infected; the main objective of the modern therapeutic strategies is the induction and maintenance of remission. Among the wide range of available treatments, older generation molecules: mesalazine, corticosteroids and thiopurine derivatives as well as biological drugs and biosimilars can be distinguished. Moreover, some novel biologics and small molecule drugs have shown potential in CD clinical trials, providing safe and effective results. This article provides an overview of the achievements in the field of biologic therapy, its efficacy and safety with an indication of future directions in CD treatment.

Serum eosinophilic cationic protein is correlated with food impaction and endoscopic severity in eosinophilic esophagitis

BACKGROUND/AIMS

The aim of the present study was to analyze the diagnostic accuracy of serum eosinophilic cationic protein (ECP) for eosinophilic esophagitis (EoE) and the correlation of ECP with clinical, histopathological, laboratory, and endoscopic features of EoE.

MATERIALS AND METHODS

Fifteen patients with EoE and 14 healthy controls were included in the study. Demographic parameters were recorded. EoE Endoscopic Reference Score (EREFS) was calculated according to endoscopic features, and esophageal biopsies were obtained by a single experienced endoscopist in a patient group. Serum ECP levels (μg/mL), absolute eosinophil count (U/mm3), and maximum peak of eosinophils/high-power field in esophageal biopsies were analyzed.

RESULTS

The median age of all participants was 33.0 (min-max: 18-46) years. There were 27 (93.1%) male patients. Serum ECP level was significantly higher in patients with EoE than in healthy volunteers (20.4 vs. 8.8, p<0.0001). According to the receiver operating characteristic (ROC) curve analysis, ECP had 80% sensitivity and 92.8% specificity to diagnose EoE with a cut-off value of 13.9 µg/mL (area under the ROC curve 0.895; p<0.0001; 95% CI: 0.725-0.978). EREFS (p<0.0001) and the presence of food impaction (p=0.04) were significantly correlated with ECP.

CONCLUSION

Serum ECP is an accurate non-invasive biomarker for EoE with high specificity and sensitivity. In addition, ECP is strongly correlated with EREFS and the symptom of food impaction.

[Food Allergy and Intolerance : Distinction, Definitions and Delimitation]

Immunologically mediated hypersensitivity to foods is defined as food allergy, mainly due to immunglobulins of class E (IgE) triggering immediate reactions (type I hypersensitivity) with possible involvement of mucosa, skin, airways, intestinal tract, and the vascular system. Primary food allergy is based on (early) IgE sensitization against animal (e. g., cow's milk, hen's eggs) or plant proteins (e. g. peanut, hazelnut or wheat). In the case of secondary food allergies, IgE against pollen proteins (e. g., birch) reacts to structurally related food proteins (with cross-reactions to stone and pit fruits). Non-immunological food intolerance reactions are mostly based on carbohydrate malassimilation (e. g., lactose intolerance, fructose malabsorption) and are rarely due to pseudo-allergies (e. g., flavors, dyes, preservatives) primarily in patients with chronic urticaria. Common intestinal symptoms are mainly due to functional disorders (e. g., irritable bowel disease), rarely because of inflammatory intestinal diseases (e. g., celiac disease). Histamine intolerance, gluten hypersensitivity, and so-called food type III hypersensitivities are controversial diagnoses. The aforementioned disease entities/models are of variable importance for the affected individuals, the public health system, and society in general.

Intraepithelial lymphocytes, scores, mimickers and challenges in diagnosing gluten-sensitive enteropathy (celiac disease)

The upper digestive tract is routinely scoped for several causes of malabsorption, and the number of duodenal biopsy specimens has increased notably in the last 10 years. Gluten-sensitive enteropathy (GSE) is an autoimmune disease, which shows an increasing prevalence worldwide and requires a joint clinico-pathological approach. The classical histopathology of GSE with partial or total villous blunting is well recognized, but the classification of GSE is not straightforward. Moreover, several mimickers of GSE with intraepithelial lymphocytosis have been identified in the last 20 years, with drug interactions and medical comorbidities adding to the conundrum. In this review, we report on the normal duodenal mucosa, the clinical presentation and laboratory diagnosis of GSE, the duodenal intraepithelial lymphocytes and immunophenotype of GSE-associated lymphocytes, the GSE mimickers, the differences "across oceans" among guidelines in diagnosing GSE, and the use of a synoptic report for reporting duodenal biopsies in both children and adults in the 21st century.

Co-occurrence of eosinophilic esophagitis and potential/probable celiac disease in an adult cohort: a possible association with implications for clinical practice

We describe an adult cohort with eosinophilic esophagitis (EoE) and evidence of celiac disease (CD), propose a change in diagnostic practice to better characterize these conditions, and hypothesize new directions for research. Pediatric studies postulate association between gluten sensitivity and EoE. However, few publications describe the prevalence, detection, or therapeutic and pathophysiologic implications of such association in adults. Retrospective chart review was done on patients diagnosed with EoE from 2009 to 2010 at University of Utah Hospitals and Clinics. Data included sex, age, presentation, duodenal pathology, tissue transglutaminase immunoglobulin A antibody (TTG) positivity, human leukocyte antigen (HLA) type (when indicated), and gross and microscopic Esophagogastroduodenoscopy (EGD) findings. Duodenal biopsy, TTG results, and HLA type were correlated. Endoscopy was repeated after gluten-free diet. Forty-four of 75 patients were followed in EoE specialty clinic with duodenal biopsy and TTG testing per protocol. Six EoE patients had potential or probable CD. No sex or age differences were noted between those with findings of CD and EoE and those with EoE alone. Six patients with findings of CD and EoE followed gluten-free diet. Five underwent repeat endoscopy. Three had resolution of esophageal eosinophilia. Potential or probable CD was commonly found in adults with EoE. Diagnosis of CD may be challenging due to nonspecific symptoms and insufficient duodenal biopsy and serologic testing. Furthermore, gluten-free diet resolved EoE findings in some patients, suggesting possible shared pathophysiology in some cases of EoE and CD. TTG testing and adequate duodenal biopsy may further direct clinical care for EoE patients, and studies are needed to elucidate mechanisms linking EoE and CD.

Eosinophilic gastroenteritis in a patient with Bruton's tyrosine kinase deficiency

Eosinophilic gastrointestinal diseases (EGID) are relatively rare diseases characterized by eosinophilic infiltration of the gastrointestinal tract resulting in various gastrointestinal symptoms. EGID are often caused by allergic reactions or systemic eosinophilic disorders, but their comorbidity with Bruton's tyrosine kinase (BTK) deficiency has not been previously documented. Here, we report a case of eosinophilic gastroenteritis (EG) in a patient with BTK deficiency. Despite adequate replacement immunoglobulin (Ig) therapy, trough serum IgG was not maintained. To identify the underlying cause of the low trough level and chronic diarrhea, the intestine was investigated on endoscopy. We also screened for the variable number of tandem repeat polymorphism in FCGRT. Genetic analysis could not explain the low trough IgG, but endoscopy indicated eosinophilic enterocolitis. EG may be an important differential diagnosis when primary immunodeficiency patients have chronic diarrhea or continued low serum IgG.

Recent advances in understanding/managing eosinophilic esophagitis in adults

It is an exciting time for research in eosinophilic esophagitis (EoE). As a new and increasingly prevalent disease, it is receiving considerable attention in the medical world, resulting in a flood of new insights. Clearly, a genetic predisposition seems likely with the identification of abnormalities in thymic stromal lymphopoietin (TSLP), calpain14, and eotaxin-3 genes. There are also well-defined abnormalities described in esophageal epithelial barrier function in these patients. The relationship between gastroesophageal reflux disease (GERD) and EoE remains unclear, but emerging data suggest that the concept of proton pump inhibitor responsive esophageal eosinophilia (PPIREE) may retain less importance, as this subset of patients becomes a likely subset of EoE in general. Finally, we approach the looming issue of long-term maintenance therapy. Although we lack adequate specific data on how to provide long-term pharmacologic treatment, studies clearly show that for most patients, this is a progressive disease that warrants such consideration.

Histological findings in infants with Gastrointestinal food allergy are associated with specific gastrointestinal symptoms; retrospective review from a tertiary centre

BACKGROUND

Gastrointestinal food allergy (GIFA) occurs in 2 to 4 % of children, the majority of whom are infants (<1 year of age). Although endoscopy is considered the gold standard for diagnosing GIFA, it is invasive and requires general anaesthesia. Therefore, we aimed to investigate whether in infants with GIFA, gastrointestinal symptoms predict histological findings in order to help optimise the care pathway for such patients.

METHODS

All infants <1 year of age over a 20 year period who underwent an endoscopic procedure gastroscopy or colonoscopy for GIFA were evaluated for the study. Symptoms at presentation were reviewed and compared with mucosal biopsy histological findings, which were initially broadly classified for study purposes as "Normal" or "Abnormal" (defined as the presence of any mucosal inflammation by the reporting pathologist at the time of biopsy).

RESULTS

Of a total of 1319 cases, 544 fitted the inclusion criteria. 62 % of mucosal biopsy series in this group were reported as abnormal. Infants presenting with diarrhoea, rectal (PR) bleeding, irritability and urticaria in any combination had a probability >85 % (OR > 5.67) of having abnormal histological findings compared to those without. Those with isolated PR bleeding or diarrhoea were associated with 74 % and 68 % probability (OR: 2.85 and 2.13) of an abnormal biopsy, respectively. Conversely, children presenting with faltering growth or reflux/vomiting showed any abnormal mucosal histology in only 50.8 % and 45.3 % (OR: 1.04 and 0.82) respectively.

CONCLUSIONS

Food allergy may occur in very young children and is difficult to diagnose. Since endoscopy in infants has significant risks, stratification of decision-making may be aided by symptoms. At least one mucosal biopsy demonstrated an abnormal finding in around half of cases in this selected population. Infants presenting with diarrhoea, PR bleeding, urticaria and irritability are most likely to demonstrate abnormal histological findings.

Demographic, clinical and allergological characteristics of Eosinophilic Esophagitis in a Spanish central region

BACKGROUND

Eosinophilic esophagitis (EoE) is a chronic inflammatory emerging disease of the oesophagus with immunoallergic aetiology. The allergens involved have not been clearly defined and may depend on the exposure of the population to aeroallergens or food antigens.

MATERIALS AND METHODS

Patients diagnosed with EoE between 2006 and 2011 were referred to our Allergy Section. Patch and skin prick tests (SPT) with aeroallergens and foods were performed, and total and specific IgE levels, eosinophil cationic protein levels and eosinophil count were determined.

RESULTS

43 patients were included. 36 (83.7%) were atopic. 29 patients presented choking, 19 dysphagia, 9 food impaction with urgent endoscopy, 4 chest pain, 1 isolated vomiting and 1 epigastric pain. 22 had two or more symptoms. The mean duration of symptoms was 3.73 years. Concomitant allergic diseases included rhinoconjunctivitis and/or asthma (31 patients), IgE food allergy (21 patients) and atopic dermatitis (3 patients). 32 (74%) were sensitized to aeroallergens, of which 90% were sensitized to pollens; 23 (54%) showed positive tests to foods and 12 of them (52%) to lipid transfer proteins (LTP). Of the 29 pollen-allergic patients, 15 (52%) were sensitized to plant foods and 10 (34.4%) to LTP.

CONCLUSIONS

Our findings support those reported in the literature: the disease is more common in men aged 30-40 years with at least a three-year history of symptoms of esophageal dysfunction, sensitized to pollens, the predominant aeroallergen in our area, but also to plant foods or panallergens. These results increase the evidence for an immunoallergic aetiology and can help us in the early diagnosis of EoE.