Non-IgE-mediated gastrointestinal allergies-Do they have a place in a new model of the Allergic March

Postprandial symptoms in disorders of gut-brain interaction and their potential as a treatment target

Postprandial, or meal-related, symptoms, such as abdominal pain, early satiation, fullness or bloating, are often reported by patients with disorders of gut-brain interaction, including functional dyspepsia (FD) or irritable bowel syndrome (IBS). We propose that postprandial symptoms arise via a distinct pathophysiological process. A physiological or psychological insult, for example, acute enteric infection, leads to loss of tolerance to a previously tolerated oral food antigen. This enables interaction of both the microbiota and the food antigen itself with the immune system, causing a localised immunological response, with activation of eosinophils and mast cells, and release of inflammatory mediators, including histamine and cytokines. These have more widespread systemic effects, including triggering nociceptive nerves and altering mood. Dietary interventions, including a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols, elimination of potential food antigens or gluten, IgG food sensitivity diets or salicylate restriction may benefit some patients with IBS or FD. This could be because the restriction of these foods or dietary components modulates this pathophysiological process. Similarly, drugs including proton pump inhibitors, histamine-receptor antagonists, mast cell stabilisers or even tricyclic or tetracyclic antidepressants, which have anti-histaminergic actions, all of which are potential treatments for FD and IBS, act on one or more of these mechanisms. It seems unlikely that food antigens driving intestinal immune activation are the entire explanation for postprandial symptoms in FD and IBS. In others, fermentation of intestinal carbohydrates, with gas release altering reflex responses, adverse reactions to food chemicals, central mechanisms or nocebo effects may dominate. However, if the concept that postprandial symptoms arise from food antigens driving an immune response in the gastrointestinal tract in a subset of patients is correct, it is paradigm-shifting, because if the choice of treatment were based on one or more of these therapeutic targets, patient outcomes may be improved.

A different starting line for allergic march: food protein-induced allergic proctocolitis

OBJECTIVE

The aim of this study is to investigate the long-term prognosis of food protein--induced allergic proctocolitis (FPIAP) patients, the risk of developing both allergic and gastrointestinal diseases, and to evaluate whether it leads to allergic march.

METHODS

A total of 149 children who were diagnosed with FPIAP and developed tolerance at least 5 years prior to the study and 41 children (with no history of food allergy) as a control group were enrolled. Both groups were re-evaluated for allergic diseases as well as gastrointestinal disorders.

RESULTS

The mean age of diagnosis for the FPIAP group was 4.2 ± 3.0 months, while the mean age of tolerance was 13.9 ± 7.7 months. The mean age of both FPIAP and control groups at the last visit was 101.6 ± 24.4 and 96.3 ± 24.1 months, respectively (P = 0.213). At the final evaluation of both groups, the comorbid allergic disease was significantly higher in the FPIAP group (P < 0.001). There was no significant difference between the two groups in terms of functional gastrointestinal disorders (FGIDs), eosinophilic gastrointestinal diseases, and inflammatory bowel disease (P = 0.198, 0.579, and 0.579, respectively).In the FPIAP group, the allergic disease was significantly higher at the final visit in patients with comorbid allergic disease at diagnosis (P < 0.001). In the FPIAP group, FGID was significantly higher in the group that developed allergic diseases in the future, compared to the group that did not develop allergic diseases in the future (P = 0.034). The proportion of both FGID and allergic diseases was significantly higher in subjects that developed tolerance at >18 months, compared to subjects that developed tolerance at >18 months (P < 0.001 and <0.001, respectively).

CONCLUSIONS

Patients with FPIAP may develop allergic diseases as well as FGID in the long term.

Dietary Factors May Delay Tolerance Acquisition in Food Protein-Induced Allergic Proctocolitis

BACKGROUND

Dietary and environmental factors may influence tolerance acquisition in food protein-induced allergic proctocolitis (FPIAP). This retrospective observational study explored the role of maternal diet during pregnancy and breastfeeding in tolerance acquisition in infantile FPIAP.

METHODS

Breastfed infants with FPIAP from six diverse regions in Greece were divided into two groups, based on development of tolerance to the trigger food: Group A (n = 43), before, and Group B (n = 53), after, the 6th month of age. Maternal diet during pregnancy and breastfeeding was elicited using the Mediterranean Diet Score Questionnaire and the Mediterranean Oriented Culture Specific Semi-Quantitative Food Frequency Questionnaire.

RESULTS

Mean age at diagnosis of FPIAP (1.5 months) and weaning (5.5 months) were the same in both groups. The main trigger was cow's milk. Group A received infant milk formula earlier than Group B. Group B had a higher incidence of asthma/wheeze, siblings with milk allergy, maternal smoking and rural residence. On multivariate analysis, earlier resolution of FPIAP was associated with higher maternal education and with salt intake and consumption of goat/sheep cheese during pregnancy and olive oil during breastfeeding. Consumption of multivitamins during pregnancy and meat, winter fruits, green vegetables, butter, salt, "ready-to-eat" meals and pastries during breastfeeding were correlated with longer duration of symptoms.

CONCLUSIONS

Mothers of children with FPIAP to cow's milk protein can be advised to eat more yogurt, cheese and olive oil during subsequent pregnancies, and avoid multivitamins, grilled food, "ready-to-eat" meals, pastries, meat and alcohol during breastfeeding, to reduce the duration of FPIAP presenting in future infants.

Diagnosis and management of food allergy-associated gastroesophageal reflux disease in young children-EAACI position paper

Gastro-oesophageal reflux (GOR) and food allergy (FA) are common conditions, especially during the first 12 months of life. When GOR leads to troublesome symptoms, that affect the daily functioning of the infant and family, it is referred to as GOR disease (GORD). The role of food allergens as a cause of GORD remains controversial. This European Academy of Allergy and Clinical Immunology (EAACI) position paper aims to review the evidence for FA-associated GORD in young children and translate this into clinical practice that guides healthcare professionals through the diagnosis of suspected FA-associated GORD and medical and dietary management. The task force (TF) on non-IgE mediated allergy consists of EAACI experts in paediatric gastroenterology, allergy, dietetics and psychology from Europe, United Kingdom, United States, Turkey and Brazil. Six clinical questions were formulated, amended and approved by the TF to guide this publication. A systematic literature search using PubMed, Cochrane and EMBASE databases (until June 2021) using predefined inclusion criteria based on the 6 questions was used. The TF also gained access to the database from the European Society of Paediatric Gastroenterology and Hepatology working group, who published guidelines on GORD and ensured that all publications used within that position paper were included. For each of the 6 questions, practice points were formulated, followed by a modified Delphi method consisting of anonymous web-based voting that was repeated with modified practice points where required, until at least 80% consensus for each practice point was achieved. This TF position paper shares the process, the discussion and consensus on all practice points on FA-associated GORD.

A comprehensive summary of disease variants implicated in metal allergy

Allergic disease represents one of the most prominent global public health crises of the 21^st century. Although many different substances are known to produce hypersensitivity responses, metals constitute one of the major classes of allergens responsible for a disproportionately large segment of the total burden of disease associated with allergy. Some of the most prevalent forms of metal allergy - including allergic contact dermatitis - are well-recognized; however, to our knowledge, a comprehensive review of the many unique disease variants implicated in human cases of metal allergy is not available within the current scientific literature. Consequently, the main goal in composing this review was to (1) generate an up-to-date reference document containing this information to assist in the efforts of lab researchers, clinicians, regulatory toxicologists, industrial hygienists, and other scientists concerned with metal allergy and (2) identify knowledge gaps related to disease. Accordingly, an extensive review of the scientific literature was performed - from which, hundreds of publications describing cases of metal-specific allergic responses in human patients were identified, collected, and analyzed. The information obtained from these articles was then used to compile an exhaustive list of distinctive dermal/ocular, respiratory, gastrointestinal, and systemic hypersensitivity responses associated with metal allergy. Each of these disease variants is discussed briefly within this review, wherein specific metals implicated in each response type are identified, underlying immunological mechanisms are summarized, and major clinical presentations of each reaction are described.Abbreviations: ACD: allergic contact dermatitis, AHR: airway hyperreactivity, ASIA: autoimmune/ autoinflammatory syndrome induced by adjuvants, BAL: bronchoalveolar lavage, CBD: chronic beryllium disease, CTCL: cutaneous T-cell lymphoma, CTL: cytotoxic T-Lymphocyte, DRESS: drug reaction with eosinophilia and systemic symptoms, GERD: gastro-esophageal reflux disease, GI: gastrointestinal, GIP: giant cell interstitial pneumonia, GM-CSF: granulocyte macrophage-colony stimulating factor, HMLD: hard metal lung disease, HMW: high molecular weight, IBS: irritable bowel syndrome, Ig: immunoglobulin, IL: interleukin, LMW: low molecular weight, PAP: pulmonary alveolar proteinosis, PPE: personal protective equipment, PRR: pathogen recognition receptor, SLE: systemic lupus erythematosus, SNAS: systemic nickel allergy syndrome, Th: helper T-cell, UC: ulcerative colitis, UV: ultraviolet.

Atopic Dermatitis and Food Allergy: A Complex Interplay What We Know and What We Would Like to Learn

Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by intense pruritus, eczematous lesions, and relapsing course. It presents with great clinical heterogeneity, while underlying pathogenetic mechanisms involve a complex interplay between a dysfunctional skin barrier, immune dysregulation, microbiome dysbiosis, genetic and environmental factors. All these interactions are shaping the landscape of AD endotypes and phenotypes. In the “era of allergy epidemic”, the role of food allergy (FA) in the prevention and management of AD is a recently explored “era”. Increasing evidence supports that AD predisposes to FA and not vice versa, while food allergens are presumed as one of the triggers of AD exacerbations. AD management should focus on skin care combined with topical and/or systemic treatments; however, in the presence of suspected food allergy, a thorough allergy evaluation should be performed. Food-elimination diets in food-allergic cases may have a beneficial effect on AD morbidity; however, prolonged, unnecessary diets are highly discouraged since they can lead to loss of tolerance and potentially increase the risk of IgE-mediated food allergy. Preventive AD strategies with the use of topical emollients and anti-inflammatory agents as well as early introduction of food allergens in high-risk infants seem promising in managing and preventing food allergy in AD patients. The current review aims to overview data on the complex AD/FA relationship and provide the most recent developments on whether food allergy interventions change the AD course and vice versa.

The Cow's Milk Related Symptom Score: The 2022 Update

CoMiSS® was developed 7 years ago to increase the awareness of health care professionals towards the possibility that symptoms presented by infants could be related to cow’s milk. While CoMiSS was conceived mostly on theoretical concepts, data is now available from 25 clinical trials. Based on this extensive research using the tool since 2015, we aim to propose an updated CoMiSS. The evidence was reviewed, debated and discussed by 10 experts, of whom seven were part of the original group. The panel concluded that the cut-off previously proposed to indicate the likelihood that symptoms may be cow’s milk related should be lowered from ≥12 to ≥10. Data in healthy infants > 6 months are missing. Since the Brussels Infant and Toddlers Stool Scale (BITSS) was recently developed for non-toilet trained children, the Bristol Stool Scale was changed to the BITSS without changing the impact of stool characteristics on CoMiSS. Overall, CoMiSS raises awareness that symptoms might be cow’s milk related. New studies are needed to determine if the change in cut-off and other small adaptions improve its sensitivity and specificity. Data for CoMiSS is still needed in presumed healthy infants between 6 and 12 months old. There may also be regional differences in CoMiSS, in healthy infants as well as in those with cow’s milk allergy. Finally, we emphasize that CoMiSS is an awareness tool and not a diagnostic test.

Synbiotic containing extensively hydrolyzed formula improves gastrointestinal and atopic symptom severity, growth, caregiver quality of life, and hospital-related healthcare use in infants with cow's milk allergy

Background

Healthy gut microbiota is important for prognosis in cow's milk allergy (CMA). The application of synbiotics (specific pre‐ and probiotics) in extensively hydrolyzed formulae (eHFs) is a relatively new concept.

Aims

To evaluate a synbiotic‐containing, whey‐based eHF (SeHF) with galacto‐oligosaccharides, fructo‐oligosaccharides, and bifidobacterium breve M‐16V in infants with CMA.

Materials and Methods

A 31‐day one‐arm pilot study in 29 infants with CMA (mean age 30.8 weeks [SD 11]) was undertaken, with outcomes including gastrointestinal tolerance, atopic dermatitis symptoms, dietary intake, growth, SeHF acceptability, caregiver quality of life, and hospital‐related healthcare use.

Results

Significant improvements (p < .05) in the severity of abdominal pain (in 57%), burping (in 46%), flatulence (in 79%), constipation (in 14%), rhinitis (41%), and itchy eyes (73%), as well as atopic dermatitis in those with severe baseline symptoms (PO‐SCORAD^© reduction: 34.7–18.2 (p = .003), n = 6) were observed over time. Growth and caregiver quality of life scores significantly increased (+26.7%, p < .05) over time. Hospital visits and medications significantly reduced (−1.61 and −2.23, respectively, p < .005) in the 6 months after SeHF initiation.

Discussion

In this small, single‐arm, pilot study, the use of SeHF enhanced the management of infants with non‐IgE mediated CMA who were already established on eHF. Conclusion: Whilst this study adds to the evidence base for the use of SeHF in CMA, further robust research to explore the longer‐term benefits of synbiotics, specifically the blend used in this study, for the clinical management of infants with CMA is warranted.

Case Report: Food Protein-Induced Protein Losing Enteropathy (FPIPLE) in Infancy

Food-protein induced protein-losing enteropathy (FPIPLE) is a mixed IgE and non-IgE food allergy in infants along with eosinophilic gastrointestinal (GI) diseases (EGID). It is characterized by poor weight gain, edema, due to hypoproteinemia/hypoalbuminemia by enteral loss of proteins, anemia, eosinophilia, raised fecal α1-antitrypsin (α1AT), and specific-IgE and allergy skin prick test (SPT) positive for offending foods. Here, we describe 4 cases with the same clinical pattern (edema due to hypoproteinemia/hypoalbuminemia from enteral loss of proteins, confirmed by high α1AT in the stools and no other pathological findings explaining the hypoproteinemia including normal kidney and liver function parameters), and propose the term “food-protein induced protein-losing enteropathy” (FPIPLE) to define this clinical entity. We also propose diagnostic criteria and an empirical algorithm of a practical approach to the diagnosis and management for children suspected to have FPIPLE. These infants can be managed successfully with dietary modification. In our 4 cases, initially, an empirical elimination diet was applied, comprising the foods that had benn introduced in the infant's diet during the last month and, an extensively hydrolyzed or elemental formula was given. In a second approach, after evaluation by a pediatric allergist, an allergy test-directed dietary elimination alimentation was implemented, for mother and/or infant. It has yet to be demonstrated whether patients with FPIPLE are a subset of patients with EGID, and whether early intervention modifies the natural course.

Food Allergy a Constant Concern to the Medical World and Healthcare Providers: Practical Aspects

Food allergy (FA) is a condition with a growing incidence and is a constant concern for the medical world and healthcare providers. With potential symptoms including anaphylaxis, in the event of an allergic reaction the patient’s life may well be endangered. The diagnosis of FA is a continuous challenge because mild cases tend to be ignored or diagnosed late and young children with allergies are cared for by parents, who are not always able to accurately interpret symptoms. It is very important to be able to differentiate FAs from food intolerance and toxic reactions to food. An accurate diagnosis is required to provide personalized management of an FA. More sophisticated and accurate diagnostic tests, including component diagnosis and epitope reactivity, allow the provision of a directed diagnosis, a more accurate therapeutic approach, and a useful prognostic evaluation. Tests used in current practice include the specific search for serum IgE, elimination diets, oral food challenges, single, blind, and double-blind (DBPCFC) tests, as well as skin tests. The risk of anaphylaxis can be assessed by molecular diagnostics/component-resolved diagnosis (CRD) and by conducting a basophilic activation test (BAT). These tests allow a planned, personalized treatment based on molecular and clinical profiles. CRD can determine the individual profile of allergic molecular reactivity and enable the formulation of a prognostic judgment. Our article highlights the importance of knowing the immune mechanisms, diagnostics, and immunotherapies in FAs. Starting from observing exposure to food allergens, to identifying allergic reactions, analysing the severity of clinical manifestations, noting the possibilities of diagnosis, and illustrating adequate management strategies.

A Prospective Assessment of Clinical Characteristics and Responses to Dietary Elimination in Food Protein-Induced Allergic Proctocolitis

BACKGROUND

Some aspects of diagnostic elimination/challenge diets in food protein-induced allergic proctocolitis (FPIAP) are still poorly defined.

OBJECTIVE

This study investigated the symptom spectrum, time required for resolution of each symptom, triggering foods, and risk factors for multiple food allergies (MFA) in FPIAP.

METHODS

Infants referred with visible blood in stool were enrolled after etiologies other than FPIAP had been excluded. Laboratory evaluation, clinical features, and elimination/challenge steps were performed prospectively during diagnostic management.

RESULTS

Ninety-one of 102 infants (53 boys) were diagnosed with FPIAP. Eleven children did not bleed during challenges. Visible blood in stool began before 2 months of age in 63.6% of the infants not diagnosed with FPIAP, compared with 18.9% of the patients with FPIAP (P = .003). Offending foods were identified as cow's milk (94.5%), egg (37.4%), beef (10.9%), wheat (5.5%), and nuts (3.3%). MFA was determined in 42.9% of patients. Multivariate logistic regression analysis identified atopic dermatitis (AD) (odds ratio [OR]: 2.98, 95% confidence interval [CI]: 1.18-7.55, P = .021) and an eosinophil count ≥300 cells/μL (OR: 2.72, 95% CI: 1.09-6.80, P = .032) as independent risk factors for MFA. Blood and mucus in stool disappeared in a median 3 days (interquartile range [IQR]: 1-14.5 days) and 30 days (IQR: 8-75 days), respectively.

CONCLUSIONS

A tendency to transient bleeding occurs in infants who present with bloody stool before 2 months of age. A 2-week duration of elimination for blood in stool is sufficient to reach a judgment of suspected foods for FPIAP. Mucus in stool is the last symptom to disappear. Concurrent AD suggests a high probability of MFA in FPIAP.

Nutritional Management With a Casein-Based Extensively Hydrolysed Formula in Infants With Clinical Manifestations of Non-IgE-Mediated CMPA Enteropathies and Constipation

Background: The majority of mixed-fed infants with non-IgE-mediated cow's milk protein allergy (CMPA) enteropathies are managed with an extensively hydrolysed cow's milk based infant formula (eHF). Given the high variability in peptide distribution of available eHFs, it is important to understand the suitability of a specific product in the management of distinct phenotypes.

Objective: To assess the symptom resolution of various phenotypes of clinical manifestations of CMPA enteropathies and constipation managed by a casein-based eHF.

Methods: The data of 20 full-term infants (n = 15 with non-IgE-mediated CMPA and n = 5 with constipation) attending a paediatric allergy clinic in Cyprus and managed with a casein-based eHF were retrospectively analysed.

Results: Based on the clinical symptoms and history, infants were classified into the following phenotypes: (a) 11/15 (73.3%) FPIAP, (b) 3/15 (20%) FPIES, and (c) 1/15 (6.7%) severe diarrhoea. Overall, 14 (93.3%) patients were successfully managed with the casein-based eHF and 1 (6.7%) required an AAF. This formula was effective in 91% of patients with FPIAP, in 100% with FPIES and with diarrhoea. Three (60%) patients with constipation responded to the eHF.

Conclusion: This case-series report supports the efficacy of a particular casein-based eHF for the nutritional management of non-IgE mediated CMPA enteropathies.

Advances on the rapid and multiplex detection methods of food allergens

With the gradually increasing prevalence of food allergy in recent years, food allergy has become a major public health problem worldwide. The clinical symptoms caused by food allergy seriously affect people's quality of life; there are unknown allergen components in novel food and hidden allergens caused by cross contamination in food processing, which pose a serious risk to allergy sufferers. Thus, rapid and multiplex detection methods are required to achieve on-site detection or examination of allergic components, so as to identify the risk of allergy in time. This paper reviews the progress of high-efficiency detection of food allergens, including enhanced traditional detection techniques and emerging detection techniques with the ability high-throughput detection or screening potential food allergen, such as xMAP, biosensors, biochips, etc. focusing on their sensitivity, applicability of each method in food, along with their pretreatment, advantages, limitation in the application of food analysis. This paper also introduces the challenges faced by these high-efficiency detection technologies, as well as the potential of customized allergen screening methods and rapid on-site detection technology as future research directions.

Gastrointestinal immunopathology of food protein-induced enterocolitis syndrome and other non-immunoglobulin E-mediated food allergic diseases

OBJECTIVE

To provide a concise summary of the current literature regarding gastrointestinal immunopathology of food protein-induced enterocolitis syndrome (FPIES) and other non-immunoglobulin E (IgE)-mediated food allergic diseases.

DATA SOURCES

Data were extracted from PubMed, MEDLINE, and ScienceDirect databases.

STUDY SELECTIONS

Original articles, review articles, and guidelines published in the past 5 years in peer-reviewed journals were first summarized. The original articles cited were then reviewed and relevant results were extracted.

RESULTS

Patients with FPIES and non-IgE-mediated food allergic diseases developed vomiting, diarrhea, and food aversion expelled food allergen from their bodies. Aside from T helper type 2 (T_H2) immunity, T_H1, T_H17, innate immunity, and epithelial mucosal barrier defect were also found to be important in the pathogenesis. Eosinophils, widely identified in the biopsy samples, were key players or were late-recruited cells for tissue repairs in those diseases. Intestinal dysbiosis and their metabolites stimulated enterochromaffin cells or enteroendocrine cells to produce serotonin, interfering with intestinal motility and subsequently affecting brain function. FPIES and non-IgE-mediated food allergic diseases were likely part of the atopic march. Allergic inflammation in intestinal mucosa might result in subsequent inflammation in the airway mucosa, suggesting the theory of "one mucosa, one disease."

CONCLUSION

The immune responses of FPIES and non-IgE-mediated food allergic diseases were not limited to the gastrointestinal tract, but also trigger wider inflammatory responses beyond it. Further research will be required to determine the systemic effect and intestinal microbiome of those diseases.

Validation of the analytical performance of the NOVEOS™ System, a system which improves upon the third-generation in vitro allergy testing technology

Objectives

Detection of allergen-specific immunoglobulin E (sIgE) is important for the diagnosis of allergy. IgE sensitization is commonly demonstrated in vivo by skin prick testing (SPT), or in vitro utilizing automated systems. Recently, HYCOR® Biomedical launched its new system for allergen sIgE testing called the NOVEOS™ Immunoanalyzer. This study aims to evaluate the analytical performance of the NOVEOS system in a bi-center study at Philipps-University Marburg (Site-1) and Charité Medical University Berlin (Site-2), respectively.

Methods

The analytical performance was evaluated based on the guidelines I/LA20-A3, EP5-A3, EP17-A2, EP6-A, EP7-A3, and EP9-A3 of the Clinical and Laboratory Standards Institute (CLSI).

Results

The conducted repeatability and within-laboratory precision tests provided acceptable performance with 3.0%–11.9% coefficient of variation across both sites. The limit of blank (LoB) and limit of detection (LoD) were <0.1 kU/L at both centers. A within-parameter linearity for all tested allergens was reported at both sites. Of note, no significant interference was observed for high levels of biotin, methylprednisolone, diphenhydramine, omalizumab, or ranitidine. Method comparison between the NOVEOS calibration and the latest World Health Organization (WHO) reference standard showed good agreement at both sites.

Conclusions

The results from the analytical performance of the NOVEOS allergen sIgE assay and instrument testing at both sites were comparable. Overall, a good precision and linearity as well as a detection limit <0.1 kU/L were observed, with minimal impact of common interfering substances on patient recoveries. The NOVEOS is calibrated to the latest WHO reference standard and adds benefits like a small sample size and para-magnetic microparticles that improve upon third-generation allergen sIgE assays’ design and performance.