Anti-TNF, infliximab, and adalimumab can be effective in eosinophilic bowel disease

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

BACKGROUND/OBJECTIVES

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

METHODS

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

RESULTS

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

Eosinophilic gastritis and gluten-sensitive enteropathy manifested as hypoproteinemia and treated with omalizumab: a case report

BACKGROUND

Eosinophilic gastritis (EoG) has rarely been reported in conjunction with gluten-sensitive enteropathy (GSE). When this does occur, patients typically present with gastrointestinal symptoms. To our knowledge, hypoproteinemia has not been reported as the primary manifestation. Anti-IgE therapy, such as omalizumab, lowers eosinophil counts in the blood, lungs, and gut. Its efficiency in treating active EoG remain unknown.

CASE PRESENTATION

We report a 33-month-old boy with a history of food allergy and atopic dermatitis who developed recurrent edema, hypoproteinemia, and eosinophilia at the age of 14 months. The diagnoses of EoG and GSE were confirmed based on the clinical presentation and results of gastrointestinal biopsies and serological testing. Although prednisone and dietary intervention were initially effective, the boy developed prednisone-related facial swelling. After stopping prednisone, his symptoms relapsed. Subsequent treatment with omalizumab, combined with dietary intervention, showed good efficacy and safety.

CONCLUSIONS

To our knowledge, this is the first case of concurrent EoG and GSE that presented primarily with hypoproteinemia. We highlight the rare manifestations of these two diseases to raise clinical suspicion and prevent missed and delayed diagnoses. The pathogenesis of EoG is heterogeneous and complex. Omalizumab showed good efficacy, indicating that IgE-mediated processes may be involved in the pathogenesis of this patient's diseases.

Successful Treatment of Eosinophilic Enterocolitis in an Adult Patient With Adalimumab

Eosinophilic gastrointestinal diseases are increasing in prevalence, but understanding of their causes and effective treatments remain elusive, especially in adults. We present a case of eosinophilic gastroenteritis and colitis with extraintestinal manifestations that was successfully treated with a tumor necrosis factor α inhibitor, adalimumab.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders Beyond Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs.

METHODS

The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment.

RESULTS

The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed.

CONCLUSION

Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

Eosinophilic Gastritis/Gastroenteritis

PURPOSE OF REVIEW

Eosinophilic gastritis/gastroenteritis (EG/EGE) are rare eosinophilic infiltrative disorders in children and adults that fall under the umbrella term eosinophilic gastrointestinal disorders (EGIDs). EGIDs also include eosinophilic esophagitis (EoE) and eosinophilic colitis. In this article, we present the current literature regarding the clinical presentation, diagnostic criteria, and management of EG/EGE.

RECENT FINDINGS

The underlying complex pathophysiology remains unknown, yet hypersensitivity response is a central component. Unlike EoE, standardized diagnostic criteria are lacking but, promising research employing tissue-based and blood-based methods of diagnosis have been reported. Non-EoE EGIDs are more challenging to treat than EoE. More than a third of patients may achieve spontaneous remission. Still, most will require dietary elimination and/or pharmaceutical interventions, mainly corticosteroids, but also biologics (monoclonal antibodies against IL-4, IL-5, TNFα, integrin α4β7, and IgE), mast-cell stabilizers, leukotriene (LT)-receptor antagonists, and antihistamines. Promising research suggests the role of AK002, an anti-siglec antibody, in clinical and histological improvement. Given the rarity and underdiagnosis of EG/EGE, different natural progression compared to EoE, heterogeneous clinical manifestations, and probable normal endoscopic appearance, it is vital to maintain a high suspicion index in atopic patients, obtain at least 5-6 random biopsies from each site for gastro/duodenal eosinophilic infiltrate with the subsequent exclusion of inflammatory, allergic and infectious differential diagnoses to increase the yield of an accurate diagnosis. Corticosteroids remain the mainstay of treatment, often requiring long-term use. Steroid-sparing agents remain experimental. Goals of therapy move beyond clinical remission but lack evidence to support histological remission.

Comorbid Diagnosis of Eosinophilic Esophagitis and Inflammatory Bowel Disease in the Pediatric Population

BACKGROUND AND AIMS

The incidence and prevalence of eosinophilic esophagitis (EoE) and inflammatory bowel disease (IBD) are rising with similar patterns. Co-occurrence of both diseases in the same patient has been increasingly reported. We sought to examine the pediatric population with both EoE and IBD to better understand the epidemiology and clinical implications of this overlap.

METHODS

We conducted a retrospective case-control study at 2 tertiary care children's hospitals. Subjects with both EoE and IBD were identified and compared with randomly selected controls with EoE and IBD alone in terms of: demographics, atopic conditions, IBD classification, location and phenotype of Crohn disease (CD), IBD medications, endoscopic findings, and histopathology. Descriptive statistics summarized the data.

RESULTS

Sixty-seven subjects with dual-diagnosis were identified across both institutions. The prevalence of IBD in the EoE population was 2.2% and EoE in IBD was 1.5%. Subjects with both diseases were more likely to have IgE-mediated food allergy compared with IBD alone (36% vs 7%, P < 0.001). Subjects with CD-EoE were less likely to have perianal disease than CD alone (2% vs 20%, P = 0.004). There was no difference in fibrostenotic EoE between the dual-diagnosis group and EoE alone. Treatment with a TNF-alpha inhibitor (anti-TNF) for management of preexisting IBD was protective against development of EoE with a relative risk of 0.314 [95% confidence interval [CI] 0.159-0.619].

CONCLUSIONS

This is a unique population in whom the underlying pathway leading to dual-diagnosis is unclear. Concomitant atopic conditions, especially IgE-mediated food allergy, and medication exposures, particularly anti-TNFs, may help predict likelihood of developing dual-diagnosis.

Eosinophilic colitis in adults

Eosinophilic colitis (EoC) is a pathological entity associated with abnormal infiltration of colonic mucosa by eosinophilic polynuclear cells (Eo). This is a relatively common pathology in infants and children under 2 years old, but is more rare and has been less studied in adults. EoC can be classified as primary or secondary. Primary EoC is, in the majority of cases, related to an allergic reaction, either IgE-mediated and capable of causing an anaphylactic-type food allergy, or not mediated by IgE and capable of giving rise to food enteropathy. The symptoms for adults with EoC are variable and non-specific, diarrhoea and abdominal pain being the most common signs. There is no histological consensus for the diagnosis of EoC. The presence of over 40 Eo per high-power field (×400) in at least two different colonic segments could be suggested as the criterion for the diagnosis. In adults with primary EoC, skin tests are of limited value and the response to a restrictive diet is less effective than in young children, given that IgE or non-IgE-mediated allergic reactions are rarely identified and EoC generally require medical treatment. There is no consensus on the treatment of EoC, but the potential efficacy of corticosteroids and budesonide has been demonstrated in the vast majority of cases studied.

Daily Dilemmas in Pediatric Gastrointestinal Pathology

The evaluation of gastrointestinal pathology in children often requires a different approach from that in adults. In this concise review, the authors outline 3 diagnostic challenges that are often encountered in daily practice; these include eosinophilic diseases, duodenal intraepithelial lymphocytosis with preserved villous architecture, and terminal ileal inflammation in the setting of idiopathic inflammatory bowel disease.

Eosinophilic Gastrointestinal Diseases in Children: A Practical Review

Primary eosinophilic gastrointestinal diseases (EGIDs) represent a heterogeneous group of disorders characterized by eosinophilic inflammation in the absence of known causes for eosinophilia, selectively affecting different segments of the gastrointestinal tract. While pediatric eosinophilic esophagitis (EoE) is a well-defined disease with established guidelines, Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC) remain a clinical enigma with evidence based on limited anecdotal case reports. Large cross-sectional studies in the US defined a prevalence of EoG and EoGE ranging from 1,5 to 6,4/100.000 and from 2,7 to 8,3/100.000 subjects respectively, while the prevalence of EoC ranges from 1,7 to 3,5/100.000 subjects. Regarding the pathogenesis, it is hypothesized that EGIDs result from the interplay between genetic predisposition, intestinal dysbiosis and environmental triggers. Clinically, EGIDs might present with different and nonspecific gastrointestinal symptoms depending on the involved intestinal tract and the extension of eosinophilic inflammatory infiltrate. The diagnosis of EGIDs requires: 1. recurrent gastrointestinal symptoms, 2. increased eosinophils for high power field in biopsy specimens, 3. absence of secondary causes of gastrointestinal eosinophilia. No validated guidelines are available on the clinical management of patients with EGIDs. Evidence from case reports and small uncontrolled case series suggests the use of dietary and corticosteroids as the first-line treatments. Considering the clinical follow-up of EGIDs, three different patterns of disease course are identified: single flare, recurring course-disease and chronic course-disease. This review will focus on pediatric EGIDs distal to esophagus, including Eosinophilic Gastritis (EoG), Eosinophilic Gastroenteritis (EoGE) and Eosinophilic Colitis (EoC).

Eosinophilic Gastroenteritis: Clinical Manifestation, Natural Course, and Evaluation of Treatment with Corticosteroids and Vedolizumab

BACKGROUND

Eosinophilic gastroenteritis (EGE) is a rare, chronic inflammatory condition of the gastrointestinal tract. Little is known about its natural history and treatment outcomes. The aims of our analysis were to describe clinical presentation, response to current medical treatments, and to evaluate the response of refractory EGE to anti-integrin therapy.

METHODS

Patients with confirmed diagnosis of EGE fulfilling the diagnostic criteria: (1) the presence of gastrointestinal symptoms, (2) dense eosinophilic infiltration of the gastrointestinal mucosa, and (3) exclusion of other conditions leading to gastrointestinal eosinophilia were included in this analysis. In patients non-responding to corticosteroids and/or anti-TNF treatment the integrin blocker vedolizumab was used.

RESULTS

EGE patients (n = 22) were predominantly female (63%) with a median age at diagnosis of 41.5 years. The most frequent symptoms were abdominal pain (100%), diarrhea (59%), nausea/vomiting (36%), and bloating (27%). No pathognomonic endoscopic alterations were found. Eosinophilic infiltration was observed in the majority of patients in more than one segment. Patients were treated with systemic steroids, topical, and enteral release steroids in 21/22 (95%) patients, proton pump inhibitors in 7/22 (32%), TNFα inhibitors in 3/22 (14%), and vedolizumab in 4/22 (18%) patients. In 3/4 of steroid-refractory patients vedolizumab induced a clinical and histological improvement.

CONCLUSIONS

The combination of highly variable clinical presentation, subtle endoscopic abnormalities, and involvement of several GI segments undermines the difficulty to diagnose EGE and the need for structured biopsy sampling. Corticosteroids were efficient in the majority of patients to induce remission. Response to the integrin blocker vedolizumab suggests further assessment in refractory cases.

Eosinophilic gastroenteritis: diagnosis and clinical perspectives

Eosinophilic gastroenteritis (EGE) is a digestive disorder in children and adults that is characterized by eosinophilic infiltration in the stomach and intestine. The underlying molecular mechanisms predisposing to this disease are unknown, but it seems that hypersensitivity response plays a major role in its pathogenesis, as many patients have a history of seasonal allergies, food sensitivities, asthma, and eczema. Symptoms and clinical presentations vary, depending on the site and layer of the gastrointestinal wall infiltrated by eosinophils. Laboratory results, radiological findings, and endoscopy can provide important diagnostic evidence for EGE; however, the cornerstone of the diagnosis remains the histological examination of gastric and duodenal specimens for evidence of eosinophilic infiltration (>20 eosinophils per high-power field), and finally clinicians make the diagnosis in correlation with and by exclusion of other disorders associated with eosinophilic infiltration. Although spontaneous remission is reported in around 30%–40% of EGE cases, most patients require ongoing treatment. The management options for this disorder include both dietary and pharmacological approaches, with corticosteroids being the mainstay of therapy and highly effective. The subsequent course is quite variable. Some patients have no recurrences, while a few experience recurrent symptoms during or immediately after corticosteroid interruption. An alternative therapeutic armamentarium includes mast-cell stabilizers, leukotriene antagonists, antihistamines, immunomodulators, and biological agents. In this review, we provide a summary of the different diagnostic tools utilized in practice, as well as the different therapeutic approaches available for EGE management.

Cellular and Molecular Therapeutic Targets in Inflammatory Bowel Disease-Focusing on Intestinal Barrier Function

The human gut relies on several cellular and molecular mechanisms to allow for an intact and dynamical intestinal barrier. Normally, only small amounts of luminal content pass the mucosa, however, if the control is broken it can lead to enhanced passage, which might damage the mucosa, leading to pathological conditions, such as inflammatory bowel disease (IBD). It is well established that genetic, environmental, and immunological factors all contribute in the pathogenesis of IBD, and a disturbed intestinal barrier function has become a hallmark of the disease. Genetical studies support the involvement of intestinal barrier as several susceptibility genes for IBD encode proteins with key functions in gut barrier and homeostasis. IBD patients are associated with loss in bacterial diversity and shifts in the microbiota, with a possible link to local inflammation. Furthermore, alterations of immune cells and several neuro-immune signaling pathways in the lamina propria have been demonstrated. An inappropriate immune activation might lead to mucosal inflammation, with elevated secretion of pro-inflammatory cytokines that can affect the epithelium and promote a leakier barrier. This review will focus on the main cells and molecular mechanisms in IBD and how these can be targeted in order to improve intestinal barrier function and reduce inflammation.

Eosinophilic Gastrointestinal Diseases in Childhood

Eosinophilic gastrointestinal diseases (EGIDs) comprise a group of chronic, inflammatory diseases of the gastrointestinal (GI) tract, that are characterized, clinically, by symptoms related to the dysfunction of the involved segment(s) of the GI tract, and histologically, by dense eosinophilic inflammation, in the absence of an identifiable secondary cause. The group of EGIDs comprises eosinophilic esophagitis (EoE), eosinophilic gastritis (EG), eosinophilic gastroenteritis (EGE), and eosinophilic colitis (EC). EoE is the most common and the best described EGID compared to EG, EGE, and EC. The clinical presentation of the EGIDs differs depending on the location and the extent of the eosinophilic infiltration in the GI tract, as well as its depth through the bowel wall. In the absence of biological markers, the diagnosis is based on the combination of clinical symptoms with the histological features of EGIDs, after the exclusion of secondary causes of eosinophilic inflammation of the GI tract. Treatment is individualized and includes elimination diets (mainly empiric or elemental) and/or drugs, according to the involved GI segment: proton pump inhibitors or local steroids in EoE; local or oral systemic steroids in EG/EGE limited to the duodenum; oral systemic steroids in EGE with lower small intestine and/or colon involvement. In patients with EoE, maintenance treatment with lower doses may be considered following histological remission with the means of drugs. In patients treated with elimination diets, disease food triggers identified during food reintroduction need to be further eliminated. Esophageal stenosis despite medical treatment requires endoscopic dilation, while the use of thiopurines or anti-TNF drugs may be considered in refractory or steroid-dependent EGID (other than EoE). The aim of this review is to provide the available evidence on each of the above disorders, to aid clinicians to interpret the clinical manifestations and the laboratory findings and choose the best available treatment option.

Eosinophilic colitis and colonic eosinophilia

PURPOSE OF REVIEW

Eosinophilic colitis is a rare condition, with a prevalence rate in the USA of 2-3/100 000 persons (0.003%), but diagnosed in 0.1% of biopsies in those colonoscoped for diarrhoea. Secondary colonic eosinophilia is more common and associated with systemic, colonic and infectious diseases. In this review, the latest advances in diagnosis, treatment and prognosis are summarized and discussed.

RECENT FINDINGS

What constitutes a 'normal' count of eosinophils is poorly documented but there are recent studies that establish normal colonic eosinophil ranges as well as distinguishing histological and clinical findings in primary eosinophilic colitis and secondary colonic eosinophilia in children and adults. Primary eosinophilic colitis is rare, relatively straightforward to diagnose, but may be difficult to treat. Colonic eosinophilia may be overt in parasite infection and connective tissue disease. More subtle, secondary colonic eosinophilia is a useful biomarker for gastrointestinal diseases, such as inflammatory bowel disease, colonic spirochaetosis and collagenous colitis, but the eosinophilia may more often be overlooked. A limited number of drugs are also known to cause left sided colonic eosinophilia such as clopidogrel, ibuprofen and oestroprogestinic agents.

SUMMARY

Advances in our understanding of primary eosinophilic colitis and secondary colonic eosinophilia is progressing and if present, colonic eosinophilia should point the clinician and pathologist to a list of differential diagnoses worth considering to direct optimal management.

Diagnosis, Natural History and Treatment of Eosinophilic Enteritis: a Review

PURPOSE OF REVIEW

To review recent findings regarding eosinophilic enteritis, including epidemiology, pathogenesis, natural history, and treatment.

RECENT FINDINGS

A 2017 population-based study using a US healthcare system database identified 1820 patients with a diagnosis of eosinophilic enteritis among 35,826,830 individuals. The majority of patients with eosinophilic enteritis in this study were women (57.7%), Caucasian (77.5%), and adults (> 18 years of age) (83.5%). The overall prevalence of eosinophilic enteritis was estimated at 5.1/100,000 persons. Eosinophilic enteritis, also known as eosinophilic gastroenteritis, is a rare primary eosinophilic gastrointestinal disorder (EGID) of unknown etiology characterized by the presence of an intense eosinophilic infiltrate on histopathological examination of the intestinal mucosa. The etiology of eosinophilic enteritis remains unknown. However, there is evidence to support the role of allergens in the pathogenesis of this disorder, as children and adults with EGIDs often have positive skin testing to food allergens and a family history of allergic diseases. Recent studies unraveling the role of IgE-mediated but also delayed Th2-type responses have provided insight into the pathogenesis of this disease. Eosinophilic enteritis causes a wide array of gastrointestinal symptoms such as abdominal pain, diarrhea, nausea, vomiting, bloating, or ascites, and its diagnosis requires a high degree of clinical likelihood, given the nonspecific clinical presentation and physical examination findings. Oral corticosteroids are considered to be the mainstay of treatment and are generally used for a short period with good response rates. Antihistamine drugs and sodium cromoglycate have also been used to treat patients with eosinophilic enteritis. Preliminary studies have demonstrated the potential benefit of biological therapies targeting the eosinophilic pathway such as mepolizumab, an anti-IL5 antibody, or omalizumab, an anti-IgE monoclonal antibody. Eosinophilic enteritis is generally considered to be a benign disease without relapse, but up to 50% of patients may present a more complex natural history characterized by unpredictable relapses and a chronic course.

Profiles of Lamina Propria T Helper Cell Subsets Discriminate Between Ulcerative Colitis and Crohn's Disease

BACKGROUND

Distinction between 2 forms of inflammatory bowel disease (IBD), ulcerative colitis (UC) and Crohn's disease (CD), can be challenging. Aberrant mucosal immunity suggests that CD is a T helper type 1 cell (Th1)-driven disease, whereas UC as Th2-driven response. However, whether this paradigm truly distinguishes CD from UC is controversial. We aimed to clarify the discriminating potential of lamina propria Th subsets in patients with IBD.

METHODS

Biopsies from 79 patients with IBD and 20 healthy controls were collected for Th subsets analysis (Th1:interferon γ [IFN-γ], T-bet; Th2:interleukin 13 [IL-13], Gata3; Th17:IL-17, RORγt; Treg:FoxP3). The receiver-operating characteristic curves were constructed to assess the discriminating ability by calculating the area under the receiver-operating characteristic curve. The equation with the highest area under the receiver-operating characteristic curve was applied to newly diagnosed patients to evaluate discriminating ability.

RESULTS

Patients with CD showed increased IFN-γ or T-bet cells and decreased IL-13 or Gata3 cells compared with UC. A discriminant equation composed of 4 markers (IFN-γ, T-bet, IL-13, and Gata3) yielded the highest area under the receiver-operating characteristic curve. In 36 established CD or UC, the sensitivity, specificity, positive and negative predictive probabilities were 92.6%, 55.6%, 86.2%, and 71.4% and in 14 newly diagnosed patients were 100.0%, 42.9%, 63.6%, and 100.0%. Furthermore, Gata3 cells were increased in tumor necrosis factor inhibitor therapy nonresponders compared with responders in CD. IFN-γ cells were directly and inversely proportional to disease activity in patients with CD and UC, respectively.

CONCLUSIONS

The Th1/Th2 paradigm can distinguish CD from UC and may be further associated with response to tumor necrosis factor inhibitor in CD and disease activity in patients with IBD.

Efficacy of Dietary Treatment for Inducing Disease Remission in Eosinophilic Gastroenteritis

OBJECTIVES

Various dietary interventions have been used to treat patients with eosinophilic gastroenteritis (EGE). Concrete evidence as to the effectiveness of such treatments in inducing disease remission is, however, lacking. The aim of the study was to systematically review the efficacy of dietary therapies in inducing EGE remission.

METHODS

We performed a systematic search for the MEDLINE, EMBASE, and SCOPUS libraries for studies investigating the efficacy of dietary interventions (in both histological and symptomatic remission) for children and adults with EGE and colitis.

RESULTS

The search yielded 490 references; 30 were included in the review, with most of these references being "low-quality" individual cases or short case series. No significant publication bias was found. Elemental diets in children were linked to 75.8% of clinical improvement, but few of these patients underwent a histological evaluation. Allergy-testing results have been used scarcely in EGE. Empiric elimination of allergy-associated foods was the most commonly used option. The variable results in terms of symptom relief, however, were scarcely accompanied by histological confirmation. Clinical and methodological heterogeneity hindered the performance of quantitative summaries for the efficacy of dietary therapies in inducing disease remission.

CONCLUSIONS

Symptomatic improvements reported for dietary treatment in EGE by most of the available literature are questionable because of the lack of objective evaluation of clinical changes and the very limited assessment of histological remission. Because of the relative lack of well-designed, high-quality studies, the unequivocal use of dietary treatment for patients with EGE and colitis cannot be supported. Further research should be undertaken.

[Eosinophilic gastroenteritis and colitis in pediatric patients: Increasingly frequent diseases]

Eosinophilic gastrointestinal disorders are a heterogeneous group of disorders characterized by no specific digestive symptoms associated with dense eosinophilic inflammation of the gastrointestinal tract in the absence of known causes for such tissue eosinophilia. Among these diseases, eosinophilic gastroenteritis (EGE) and colitis (EC) are less common than esophagitis, but their incidence and prevalence have been increasing over the past decade due in part to increased disease recognition. The exact pathophysiology is not clear: EGE and EC are immune-mediated diseases implicating adaptive T-helper cell type 2 immunity. According to the site of eosinophilic infiltration, there is a wide spectrum of digestive symptoms ranging from food refusal, nausea, vomiting, abdominal pain, weight loss, gastrointestinal bleeding (anemia), protein loosing enteropathy, ascites, bowel obstruction or perforation for EGE and diarrhea ± bleeding for CE. Endoscopic lesions are not specific: friability, erythematous mucosa with superficial erosions, or ulceration is often observed. Histologically, markedly increased numbers of mucosal eosinophils are seen in biopsy specimens. However, no standards for the diagnosis of EGE or CE exist and few findings support the diagnosis: intraepithelial eosinophils, eosinophil crypt abscesses, and eosinophils in muscularis mucosa and/or submucosa. Other organs are not involved. The other causes of tissue eosinophilia (infections, inflammatory bowel diseases) should be excluded. Food allergy appears to play a central role in driving inflammation in EGE and CE, as evidenced by symptomatic improvement with initiation of food exclusion or elemental diets. Dietary treatment should be the first therapeutic option in children. If the elimination diet fails, corticosteroids are currently the best characterized treatment but appropriate duration is unknown and relapses are frequent. In severe forms, immunomodulators or biologic agents (anti-IL5, anti-IgE, or anti-TNFa) can potentially play a role in the treatment of EGE and CE.

The management of eosinophilic gastroenteritis

Eosinophilic gastroenteritis (EG) is a rare disorder characterized by eosinophilic infiltration of the gastrointestinal tract. No medication at present is approved by the Food and drug administration of United States for the treatment of EG. The rarity of the disease limits our experience with the different management options. It also limits the ability to conduct randomized controlled trials that could clearly delineate the efficacy of new therapeutic agents. This review assesses the various management options that have been tried on patients with EG.

Eosinophils and mast cells as therapeutic targets in pediatric functional dyspepsia

There is an increasing appreciation for the importance of inflammation as a pathophysiologic entity that contributes to functional gastrointestinal disorders including functional dyspepsia (FD). Importantly, inflammation may serve as a mediator between psychologic and physiologic functions. This manuscript reviews the literature implicating two inflammatory cell types, mast cells and eosinophils, in the generation of dyspeptic symptoms and explores their potential as targets for the treatment of FD. There are a number of inciting events which may initiate an inflammatory response, and the subsequent recruitment and activation of mast cells and eosinophils. These include internal triggers such as stress and anxiety, as well as external triggers such as microbes and allergens. Previous studies suggest that there may be efficacy in utilizing medications directed at mast cells and eosinophils. Evidence exists to suggest that combining “anti-inflammatory” medications with other treatments targeting stress can improve the rate of symptom resolution in pediatric FD.