Eosinophilic esophagitis improved by the discontinuation of sublingual immunotherapy for aeroallergens: a case report

Introduction

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated inflammation of the esophagus, characterized by symptoms related to esophageal dysfunction, resulting from severe eosinophilic infiltration of the esophageal mucosa. It is common in atopic subjects and food antigens have been identified as the most common triggers. However, a seasonal variation in EoE prevalence, correlated with air pollen levels, is reported, suggesting that also aeroallergens may play a role. Little is known about the interplay between EoE and concomitant atopy treatment for aeroallergens.

Case presentation

We describe the case of an 11-year-old boy who presented dysphagia, vomiting, drooling, and chest pain while eating meat, developed 15 months after receiving sublingual immunotherapy (SLIT) for Alternaria (SUBLIVAC®). He underwent esophagogastroduodenoscopy (EGD) revealing severe eosinophilic predominant inflammation (100 eos/HPF), consistent with the diagnosis of EoE, not improving at the EGDs performed after both omeprazole and topical corticosteroids treatment, despite symptom improvement. Afterward, immunotherapy was switched from sublingual to injective form. At the EGD performed 1 month later, macroscopic examination of the esophageal mucosa was normal and eosinophilic infiltration was significantly decreased (5-10 eos/HPF).

Conclusions

SLIT may induce EoE by chronic antigenic exposure of oral mucosa in patients with a robust allergic susceptibility: while attenuating the IgE-mediated immune reactions, the progressive contact with the causative allergen might induce a chronic stimulation of the immune system with the consequent activation of tissue eosinophils. Our data suggest monitoring patients receiving SLIT for EoE symptoms and to discontinue SLIT on their earlier appearance, possibly as a first-line treatment.

Oral Immunotherapy in Children: Clinical Considerations and Practical Management

Oral immunotherapy (OIT) in pediatric patients provides an alternative option to the current standard of care in food allergy, which is allergen avoidance and reactive treatment. Because patients are exposed to one or more food allergens during treatment, OIT is associated with adverse events and can be a cumbersome process for children, their caregivers, and clinicians. However, there have been an overwhelming number of studies that show high efficacy in both single- and multi-allergen OIT, and that quality of life is greatly improved for both patients and their families after undergoing immunotherapy. This review discusses clinical considerations for OIT in pediatrics, including efficacy and safety, practical management, and future directions of treatment.

Oral Immunotherapy for Food-Allergic Children: A Pro-Con Debate

The prevalence of food allergy has increased in recent years, especially in children. Allergen avoidance, and drugs in case of an allergic reaction, remains the standard of care in food allergy. Nevertheless, increasing attention has been given to the possibility to treat food allergy, through immunotherapy, particularly oral immunotherapy (OIT). Several OIT protocols and clinical trials have been published. Most of them focus on children allergic to milk, egg, or peanut, although recent studies developed protocols for other foods, such as wheat and different nuts. OIT efficacy in randomized controlled trials is usually evaluated as the possibility for patients to achieve desensitization through the consumption of an increasing amount of a food allergen, while the issue of a possible long-term sustained unresponsiveness has not been completely addressed. Here, we evaluated current pediatric OIT knowledge, focusing on the results of clinical trials and current guidelines. Specifically, we wanted to highlight what is known in terms of OIT efficacy and effectiveness, safety, and impact on quality of life. For each aspect, we reported the pros and the cons, inferable from published literature. In conclusion, even though many protocols, reviews and meta-analysis have been published on this topic, pediatric OIT remains a controversial therapy and no definitive generalized conclusion may be drawn so far. It should be an option provided by specialized teams, when both patients and their families are prone to adhere to the proposed protocol. Efficacy, long-term effectiveness, possible role of adjuvant therapies, risk of severe reactions including anaphylaxis or eosinophilic esophagitis, and impact on the quality of life of both children and caregivers are all aspects that should be discussed before starting OIT. Future studies are needed to provide firm clinical and scientific evidence, which should also consider patient reported outcomes.

BSACI 2021 guideline for the management of egg allergy

This guideline advises on the management of patients with egg allergy. Most commonly egg allergy presents in infancy, with a prevalence of approximately 2% in children and 0.1% in adults. A clear clinical history will confirm the diagnosis in most cases. Investigation by measuring egg-specific IgE (by skin prick testing or specific IgE assay) is useful in moderate-severe cases or where there is diagnostic uncertainty. Following an acute allergic reaction, egg avoidance advice should be provided. Egg allergy usually resolves, and reintroduction can be achieved at home if reactions have been mild and there is no asthma. Patients with a history of severe reactions or asthma should have reintroduction guided by a specialist. All children with egg allergy should receive the MMR vaccine. Most adults and children with egg allergy can receive the influenza vaccine in primary care, unless they have had anaphylaxis to egg requiring intensive care support. Yellow Fever vaccines should only be considered in egg-allergic patients under the guidance of an allergy specialist. This guideline was prepared by the Standards of Care Committee (SOCC) of the British Society for Allergy and Clinical Immunology (BSACI) and is intended for allergists and others with a special interest in allergy. The recommendations are evidence based. Where evidence was lacking, consensus was reached by the panel of specialists on the committee. The document encompasses epidemiology, risk factors, diagnosis, treatment, prognosis and co-morbid associations.

Eosinophilic gastrointestinal disorders and allergen immunotherapy: Lights and shadows

Allergic diseases, such as IgE-mediated food allergy, asthma, and allergic rhinitis, are relevant health problems worldwide and show an increasing prevalence. Therapies for food allergies are food avoidance and the prompt administration of intramuscular epinephrine in anaphylaxis occurring after accidental exposure. However, allergen immunotherapy (AIT) is being investigated as a new potential tool for treating severe food allergies. Effective oral immunotherapy (OIT) and epicutaneous immunotherapy (EPIT) induce desensitization and restore immune tolerance to the causal allergen. While immediate side effects are well known, the long-term effects of food AIT are still underestimated. In this regard, eosinophilic gastrointestinal disorders (EGIDs), mainly eosinophilic esophagitis, have been reported as putative complications of OIT for food allergy and sublingual immunotherapy (SLIT) for allergic asthma and rhinitis. Fortunately, these complications are usually reversible and the patient recovers after AIT discontinuation. This review summarizes current knowledge on the possible causative link between eosinophilic gastrointestinal disorders and AIT, highlighting recent evidence and controversies.

Pancreaticoduodenectomy for stricturing primary eosinophilic duodenitis

A 59-year-old woman was referred to a specialist gastroenterologist following a year of intermittent abdominal bloating and worsening reflux. In the month prior to referral, the patient developed intermittent large volume vomiting consisting of bile-stained undigested food. This was accompanied by a 10 kg weight loss. Imaging and endoscopic investigations showed a circumferential thickening of the second part of the duodenum. Biopsy showed non-specific inflammatory changes with marked eosinophilic infiltrates. A pancreaticoduodenectomy was performed. Histopathological analysis of the resection sample showed primary eosinophilic duodenitis with no evidence of malignancy. Immunological testing was only positive for coeliac disease and an infectious cause was never identified. The patient's symptoms resolved following the surgery and she was discharged from surgical follow-up after 8 years of no further symptoms.

Oral immunotherapy in food allergies: A practical update for pediatricians

Food oral immunotherapy (OIT) is a promising treatment for persistent and severe food allergies (FAs) in children, but also for accelerating tolerance to cow's milk and cooked egg in young children. In the near future, pediatricians will increasingly encounter severely allergic children undergoing FA-OIT. FA-OIT consists in daily ingestion of increasing doses of the allergen during the up-dosing phase, and ingestion of a constant dose during the maintenance phase. The global aim is to increase the reactive threshold of allergic patients, and finally enable them to ingest a target quantity of allergen without any reaction throughout the treatment (desensitization). Many studies showed the efficacy of FA-OIT in desensitization, and some of them in sustained unresponsiveness. This corresponds to tolerance after FA-OIT discontinuation, especially for cow's milk and hen's egg allergy. However, there is an ongoing debate about the safety of the treatment. Side effects are frequent, notably aversion to the allergen and oral syndromes as well as systemic allergic symptoms. These reactions occur mainly during the up-dosing phase and become less frequent with time, but they are common causes of FA-OIT discontinuation. Patients and their families must be trained to manage these reactions at home. Long-term side effects can also occur, such as eosinophilic esophagitis. Pediatricians play an important role in maintaining patient motivation; they also provide knowledge on possible allergic reactions and the reactogenic cofactors (mainly fever and viral infection, anti-inflammatory intake, physical activity), and refer the patient to the relevant specialists in the case of long-term care. Other routes of administration for food immunotherapy (epicutaneous and sublingual) and different adjuvant treatments (probiotics, anti-IgE molecule) are currently under study. This will allow us to improve the efficacy of immunotherapy and reduce the risk of any side effects, in order to provide a more favorable risk-benefit ratio.

Interdisciplinary Significance of Food-Related Adverse Reactions in Adulthood

Background: Adults frequently interpret food-associated adverse reactions as indicators of a food allergy. However, the public perception of food allergy may differ from a clinician's point of view. The prevalence of patient-reported food allergy tends to be higher than physician-confirmed cases. Dermatological manifestations (urticaria, pruritus, dermatitis, and edema) are frequently reported by patients. Objective: The aim of this study was to describe patient-reported symptoms related to suspected food allergies and particularly to characterize and highlight the volume of patients who visit Budapest allergy clinics with suspected food allergies. Methods: In this prospective study, adult (≥18 years) patients were examined at the Allergology Outpatient Unit of the Dept. of Dermatology, Venereology, and Dermatooncology, Semmelweis University, Budapest. The examination included a detailed medical history; physical examination; and when necessary the measurement of allergen-specific serum immunoglobulin E (IgE) levels. Results: Data from 501 patients (393 women, 108 men) were analyzed. Intolerance to dietary biogenic amines occurred in 250 cases (250/501, 50%). Oral allergy syndrome was confirmed in 71 patients (71/501, 14%). Allergy to food preservatives was diagnosed in 14 (14/501, 3%) cases by a dermatologist-allergist specialist. Five individuals (5/501, 1%) were diagnosed with IgE-mediated food allergy. In some cases (28/501, 6%), edema-inducing/enhancing side effects of drugs were observed which patients had misattributed to various foods. Among the food groups considered to be provoking factors, the most frequently mentioned were fruits (198/501, 40%), milk/dairy products (174/501, 35%), and nuts/oilseeds (144/501, 29%). Overwhelmingly, urticaria (47%) was the most common dermatological diagnosis, followed by dermatitis (20%) and allergic contact dermatitis (8%). Conclusion: Improvement is needed in food allergy, food intolerance, and general nutritional knowledge among the general public. According to our data, perceived/self-reported food allergies were overestimated by adults when compared against physician-confirmed food allergies; however, other diseases potentially responsible for food-related problems were underestimated. The prevalence of oral allergy syndrome was high in the cohort. Intolerance to dietary biogenic amines was common, and although the role of dietary histamine and biogenic amine is not entirely understood in eliciting patients' symptoms, improvements in complaints were reported during the control visits.

Recent Advances in Clinical Allergy and Immunology 2019

The immune system has vital functions for homeostasis and host defense. Thus, imbalances of the immune system whether associated with allergy, hypersensitivity, or autoimmunity are of great importance, as is manifest from common diseases such as atopic diseases, urticaria, and angioedema, and drug hypersensitivity reactions. These can affect patients' quality of life and can generate high costs for health care. Epidemiological studies have provided evidence for changing patterns of allergic diseases caused by lifestyle and climate changes which have consequences for medical care. Deeper insights into the pathogenesis of allergic/immunologic diseases, combined with novel technologies, provide improved diagnostic options and treatment measures. This review will summarize novel aspects of the epidemiology, pathogenic mechanisms, as well as disease management in the fields of allergy and clinical immunology.

Epicutaneous immunotherapy in rhino-conjunctivitis and food allergies: a review of the literature

Background

Epicutaneous immunotherapy (EPIT) is a new way of allergen administration that has a high rate of adherence and safety. The aim of this manuscript is to review clinical trials on EPIT for respiratory and food allergies published in the last 10 years, taking into account how different variables (i.e., dose, patch application duration, skin preparation, and efficacy and safety evaluation) have influenced study results.

Main body

From a review of the literature, we identified eight placebo-controlled, double-blind trials conducted on children and adults, including four studies on grass pollen rhino-conjunctivitis, one on cow’s milk allergy and three on peanut allergy. Different methods for skin pre-treatment, such as skin abrasion and tape stripping or stratum corneous hydration by an occlusive system, different endpoints and cumulative allergen doses, and different durations of patch application and tape stripping, were used in the rhino-conjunctivitis studies. A visual analogue system was used for the efficacy evaluation. Several local skin reactions (eczema) and some systemic adverse reactions were reported at higher rates in the active group compared to placebo in one study, but this was not shown by other authors. Local eczema reactions were correlated to the times for applying the tape stripping, while systemic side effects were correlated to the deepness of scraping. In the food allergy trials, differences in the food challenge thresholds, endpoints and allergen sites of the cutaneous patch application influenced the study results. A slight dose-dependent efficacy was found in the peanut allergy studies, which was confirmed by a more significant increase in the following progressive open study. Few adverse events and high adherence in all of the food allergen trials were reported.

Conclusions

Overall, the EPIT study results, even if they were affected by great heterogeneity among the methodologies applied, have shown not only the high safety and adherence with this kind of immunotherapy but also suggested the possibility for obtaining definitive evidence of the efficacy of EPIT, especially for food allergies.

Recent Advances in Clinical Allergy and Immunology

Allergic diseases are of great concern because of their high prevalence, which is still rising in several regions, their impact on patients' physical and psychological health, the huge burden they place on patients' quality of life, as well as the socioeconomic consequences that they cause. Recent research has provided new data on both genetic and environmental risk factors of atopic/allergic diseases. The application of new technologies such as "omics" has allowed a better understanding of the pathogenesis and has helped with the identification of therapeutic targets. Immense progress has been made in developing and applying novel, targeted therapies, for example for asthma and urticaria. Intensive efforts are being made to find biomarkers that help to classify patients, to identify their potential responsiveness to specific therapies, and to monitor the disease severity. Based on recent insights in the pathogenesis of food allergy and drug hypersensitivity, novel strategies for diagnostics, allergen avoidance, and induction of tolerance have been developed. Here, we summarize important findings in the field of clinical allergy and immunology with a special focus on asthma, allergic rhinitis, atopic dermatitis, food allergy, urticaria, angioedema, and drug hypersensitivity.

Pathophysiology of Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus associated with an atopic predisposition which appears to be increasing in prevalence over the last few decades. Symptoms stem from fibrosis, swelling, and smooth muscle dysfunction. In the past two decades, the etiology of EoE has been and is continuing to be revealed. This review provides an overview of the effects of genetics, environment, and immune function including discussions that touch on microbiome, the role of diet, food allergy, and aeroallergy. The review further concentrates on the pathophysiology of the disease with particular focus on the important concepts of the molecular etiology of EoE including barrier dysfunction and allergic hypersensitivity.

Safety and efficacy of epicutaneous immunotherapy for food allergy

Food allergy is increasingly common in children, affecting about 4%-8%. The mainstays of management remain allergen avoidance and emergency preparedness to treat allergic reactions with emergency medications. Unfortunately, these approaches are unsatisfactory for many patients and their families as the restrictions, constant vigilance, and unpredictable severity of allergic reactions negatively impact quality of life. In recent decades, there has been significant interest in developing treatments for food allergy that lead to desensitization to increase thresholds for triggering allergic reactions and decrease the risk of reacting to allergen-contaminated food products. Epicutaneous immunotherapy (EPIT) is a novel therapy that is currently under investigation, delivering allergen via repeated applications to the skin and targeting antigen-presenting cells in the superficial skin layers. Murine models have demonstrated that allergen uptake is an active process by skin dendritic cells with subsequent migration to draining lymph nodes. Allergen exposure to the non-vascularized epidermis limits systemic absorption, contributing to the high-safety profile. Results from murine experiments showed that EPIT has comparable efficacy as subcutaneous immunotherapy in terms of challenge outcomes, airway hyper-responsiveness, and immunologic parameters. Several clinical trials of EPIT have recently been completed or are ongoing. Results support the high safety and tolerability of this approach. Efficacy data suggest that the change in threshold eliciting dose following 1 year of therapy is less than that seen compared to high-dose (2-4 g peanut protein) oral immunotherapy, but more prolonged treatment with EPIT appears to lead to increasing desensitization. Additional data from larger-scale studies should provide a more robust assessment of safety and efficacy of EPIT.

Peanut gastrointestinal delivery oral immunotherapy in adolescents: Results of the build-up phase of a randomized, double-blind, placebo-controlled trial (PITA study)

BACKGROUND

Oral immunotherapy to peanut is effective in desensitizing patients but has significant side effects including anaphylaxis and gastrointestinal symptoms. In most protocols, peanut is administered in a vehicle food.

OBJECTIVE

In an exclusively adolescent population, we tested a new approach using sealed capsules of peanut (gastrointestinal delivery oral immunotherapy or GIDOIT) to bypass the upper gastrointestinal tract. The primary aim was to assess the efficacy of the oral build-up phase of GIDOIT and the secondary aim to analyse its safety.

METHODS

Adolescents with a history of a clinical allergic reaction after peanut ingestion were included in a 2-armed, parallel-design, individually randomized, double-blind, placebo-controlled, multicentre trial after a positive double-blind placebo-controlled oral food challenge (DBPCFC1). A central randomization centre used computer-generated tables to allocate treatments. Peanut (or placebo) capsules were ingested daily over a period of 24 weeks with increments every 2 weeks from 2 to 400 mg of peanut protein (pp). Primary outcome was tolerance of 400 mg of pp at DBPCFC2.

RESULTS

Thirty patients were included between September 2013 and May 2014. At DBPCFC2, unresponsiveness to 400 mg of pp was achieved in 17/21 peanut group patients (2 withdrawn patients) and 1/9 in the placebo group (Intention-to-treat analysis, P < .001, absolute difference = 0.7, 95%IC 0.43 0.96). Oropharyngeal symptoms were equally frequent in both groups. No dysphagia or other signs of eosinophilic oesophagitis occurred. Digestive adverse events (AE) were more frequent in the treated group (P = .02), but mild and without compliance issues. Only one severe advent event led to withdrawal in a patient who ingested twice the investigated treatment. Peanut-specific humoral immune responses were modulated.

CONCLUSION

The GIDOIT protocol demonstrated clinical and immunological efficacy and had an acceptable level of safety with weak oropharyngeal symptoms, no dysphagia, mild digestive events and few severe systemic AE.

Impact of allergen immunotherapy in allergic asthma

Although traditional pharmacological approaches improve outcomes in disease management for allergic asthma, these fail to modify the underlying immune responses. Allergen immunotherapy remains the only etiological therapy for the treatment of respiratory allergies for which clinical efficacy has been demonstrated through several well-controlled studies. In this review, we examine evidence from the past 5 years regarding the impact of allergen immunotherapy on allergic asthma to inform practitioners and stimulate further discussion and research.

Clinical aspects of oral immunotherapy for the treatment of allergies

Studies on oral immunotherapy (OIT) have been increasing worldwide. Nevertheless, some concerns exist with this treatment. The rate of long-term sustained unresponsiveness is quite low; moreover, the desensitization or sustained unresponsiveness does not equate to tolerance. Furthermore, adverse reactions are frequent. Therefore, safe and feasible methods for long-term therapies are needed. Novel therapies such as low-dose OIT, hypoallergenic products, and OIT in combination with omalizumab are reported as effective for inducing sustained unresponsiveness and may lead to fewer adverse reactions than standard OIT. Increased safety will contribute to feasibility of OIT. Currently, oral food challenge (OFC) with the low target dose has been reported. We may reduce the need for OIT by implementing low-dose OFC. More effective, safe, and feasible OIT strategies are needed.