Tolerance to extensively heated milk in children with cow's milk allergy

Powder milk: a user-friendly and safe product for heated-milk food challenge?

Background

Previous studies have reported that up to 75 % of milk allergic subjects tolerate heated milk products. However, the food used for heated milk challenge is often prepared in a non-standardized manner by the parents at home, which may prove inconvenient and even sometimes raise concerns with regards to test validity. Instant skim milk powder is made by a food process that involves heating skim milk to up to 250 °C (390 °F) for up to 30 min which ought to be sufficient to denature thermo-labile proteins.

Objective

To appraise the use of instant skim milk for the purpose of heated milk food challenge.

Methods

We reviewed all oral food challenges to instant skim milk powder performed at Sainte-Justine University Hospital Center in Montreal, Canada between November 2008 and January 2013 (cumulative dose of 4 g proteins).

Results

During the study period, 39 children underwent an open food challenge to instant skim milk powder. Thirty patients (76.9 %) passed the challenge without clinical reaction, of which 26 successfully introduced heated milk products at home. The remaining four children reported intermittent mild reactions to specific forms of heated milk goods while they tolerated others. Subjects’ clinical and paraclinical characteristics were comparable to previous cohorts evaluating baked milk challenge, which reported similar rates of heated milk positive challenges, ranging from 17 to 28 %.

Conclusion

Challenge with instant skim milk powder could be a safe, convenient and easily standardizable alternative to home baked food for heated milk challenge. Further controlled studies are needed before this can be implemented to practice.

Clinical Management of Food Allergy

Food allergies have become a growing public health concern. At present the standard of care focuses on avoidance of trigger foods, education, and treatment of symptoms following accidental ingestions. This article provides a framework for primary care physicians and allergists for the diagnosis, management, and treatment of pediatric food allergy.

Allergen Component Testing in the Diagnosis of Food Allergy

IgE-mediated food allergies are an important public health problem, affecting 5 % of adults and 8 % of children, with numerous studies indicating that the prevalence is increasing. Food allergic reactions can range in severity from mild to severe and life threatening. Accurate diagnosis of food allergy is necessary not only to provide appropriate and potentially life-saving preventive measures but also to prevent unwarranted dietary restrictions. The diagnosis of food allergy has traditionally been based on clinical history and food specific IgE (sIgE) testing, including skin prick testing (SPT), serum tests, or both. These tests tend to be extremely sensitive, but positive test results to foods that are tolerated are common. Studies of allergen component-resolved diagnostics (CRD) show that adjuvant use of this modality may provide a more accurate assessment in the diagnosis of food allergy, though the reported benefits are questionable for a number of major allergens. Furthermore, diagnostic cutoff values have been difficult to determine for allergens where component testing has been demonstrated to be beneficial.

Food Allergy: Common Causes, Diagnosis, and Treatment

Food allergy is a growing concern, and recognition of symptoms, knowledge of common food allergens, and management of reactions are important for patients and practitioners. Symptoms of a classic IgE-mediated food allergy vary in severity and can include any combination of laryngeal edema, wheezing, nausea, vomiting, diarrhea, urticaria, angioedema, and hypotension. Many foods can induce an allergic reaction, but the most commonly implicated foods include cow's milk, egg, peanut, tree nut, soy, wheat, fish, and shellfish. Milk and egg allergy generally develop and are outgrown in childhood. Peanut and tree nut allergy can occur during childhood or adulthood, are less likely to be outgrown, and tend to cause more fatal reactions. Given the possibility of life-threatening reactions, it is important to recognize the potential for cross-reactivity among food groups. Diagnosis of food allergy includes skin prick testing, specific serum IgE testing, and oral food challenges. Management is centered on avoidance of allergenic and cross-reacting foods and early recognition and immediate treatment of reactions. Treatment protocols to desensitize patients to food are currently under investigation.

Oral immunotherapy for food allergy: mechanisms and role in management

With the emergence of food allergy as an important public health problem, it has become clear that there is an unmet need in regard to treatment. In particular, IgE-mediated food allergy that is associated with risk of fatal anaphylaxis has been the subject of multiple studies in the past decade. The growing body of evidence derived from multiple centres and various study designs indicates that for IgE-mediated food allergy, immunomodulation through food immunotherapy is possible; however, the extent of protection afforded by such treatment is highly variable. At this time, the capacity for food immunotherapy to restore permanent tolerance to food has not been demonstrated conclusively. This review will discuss these topics as they apply to the most important studies of food oral immunotherapy.

Insoluble and soluble roasted walnut proteins retain antibody reactivity

Thermal processing techniques commonly used during food production have the potential to impact food allergens by inducing physical and/or chemical changes to the proteins. English walnuts (Juglans regia) are among the most commonly allergenic tree nuts, but little information is available regarding how walnut allergens respond to thermal processing. This study evaluated the effects of dry roasting (132 or 180°C for 5, 10, or 20min) on the solubility and immunoreactivity of walnut proteins. A dramatic decrease in walnut protein solubility was observed following dry roasting at 180°C for 20min. However, both the soluble and insoluble protein fractions from roasted walnuts maintained substantial amounts of IgG immunoreactivity (using anti-raw and anti-roasted walnut antisera), with similar patterns of reactivity observed for human IgE from walnut-allergic individuals. Thus, walnut proteins are relatively stable under certain thermal processing conditions, and IgE reactivity remains present even when insoluble aggregates are formed.

Component-resolved allergen testing: The new frontier

The discovery that allergen specific IgE (sIgE) identified individuals who were allergic to specific allergens, revolutionized allergy and immunology. Recently, component-resolved allergen testing (CRD) has shown promise in improving the field yet again. Prior to development of CRD immunoassays, whole allergen extracts were used to detect IgE mediated allergic disease either by oral, cutaneous, or conjunctival provocation. The most widely used immunoassays detect sIgE to either whole allergen sources or individual allergic components. The use of CRD micro-assay technology (not Food and Drug Administration approved in the United States) has been used to evaluate multiple allergens in parallel. This technique allows for determination of primary vs secondary sensitizations from either close sequence homology or cross-reactive carbohydrate determinants. Published studies have shown beneficial uses in hymenoptera venom immunotherapy, anaphylaxis, and food allergy. The use of component testing for aeroallergen immunotherapy has been studied, however clinical use is hampered by lack of allergen components approved for injection. Therefore, although promising in many respects, the frontier of CRD testing requires more data before it can be widely used in clinical practice.

High IgE levels to α-lactalbumin, β-lactoglobulin and casein predict less successful cow's milk oral immunotherapy

BACKGROUND

A new treatment option for persistent cow's milk allergy (CMA) is oral immunotherapy (OIT). Not all patients develop tolerance during therapy, and markers to identify those who will benefit from it are needed. The objective was to study the IgE and IgG4 antibody profiles to milk and milk proteins before and after OIT in relation to clinical outcome.

METHODS

Seventy-six children (5-17 years) with challenge-verified CMA were subjected to a 6-month OIT protocol. The treatment aimed at reaching a maintenance dose of 200 ml CM (high dose = HD). Those who did not reach target were analysed as a low-dose (LD) group. Sera were characterized before and after OIT regarding serum levels of IgE and IgG4 to milk and five milk allergen components evaluated together with clinical CMA symptoms and outcome of OIT.

RESULTS

Fifty-five (72%) patients reached the maintenance dose (HD) during therapy. High specific IgE levels towards the milk allergens α-lactalbumin (P = 0.048), β-lactoglobulin (P = 0.006) and casein (P = 0.015) before OIT start were associated with lower maintenance dose reached. Patients who developed desensitization had a larger increase in IgG4 levels to α-lactalbumin (P = 0.034), β-lactoglobulin (P = 0.010), casein (P = 0.047) and lactoferrin (P = 0.030) during treatment than those who failed.

CONCLUSIONS

Component-resolved diagnostics before OIT can help to identify children with lower probability of a successful OIT outcome, as high IgE levels to α-lactalbumin, β-lactoglobulin and casein are associated with lower maintenance dose reached. An increase in the IgG4 concentration to milk components during treatment indicated effective desensitization.

Non-IgE-mediated gastrointestinal food allergy

Non-IgE-mediated gastrointestinal food-induced allergic disorders (non-IgE-GI-FAs) account for an unknown proportion of food allergies and include food protein-induced enterocolitis syndrome (FPIES), food protein-induced allergic proctocolitis (FPIAP), and food protein-induced enteropathy (FPE). Non-IgE-GI-FAs are separate clinical entities but have many overlapping clinical and histologic features among themselves and with eosinophilic gastroenteropathies. Over the past decade, FPIES has emerged as the most actively studied non-IgE-GI-FA, potentially because of acute and distinct clinical features. FPIAP remains among the common causes of rectal bleeding in infants, while classic infantile FPE is rarely diagnosed. The overall most common allergens are cow's milk and soy; in patients with FPIES, rice and oat are also common. The most prominent clinical features of FPIES are repetitive emesis, pallor, and lethargy; chronic FPIES can lead to failure to thrive. FPIAP manifests with bloody stools in well-appearing young breast-fed or formula-fed infants. Features of FPE are nonbloody diarrhea, malabsorption, protein-losing enteropathy, hypoalbuminemia, and failure to thrive. Non-IgE-GI-FAs have a favorable prognosis; the majority resolve by 1 year in patients with FPIAP, 1 to 3 years in patients with FPE, and 1 to 5 years in patients with FPIES, with significant differences regarding specific foods. There is an urgent need to better define the natural history of FPIES and the pathophysiology of non-IgE-GI-FAs to develop biomarkers and novel therapies.

Efficacy of baked milk oral immunotherapy in baked milk-reactive allergic patients

BACKGROUND

Patients with IgE-mediated cow's milk allergy who are nonreactive to baked milk (BM) can be desensitized with BM to promote tolerance to unheated milk (UM).

OBJECTIVE

We sought to test whether patients who are BM reactive can progress in BM oral immunotherapy (OIT) and become desensitized to UM as well.

METHODS

Fifteen patients (>4 years) who previously failed to complete our milk OIT program were enrolled into the BM OIT protocol. A dose of BM (180 °C for 30 minutes) which was less than the eliciting dose was increased 50% monthly while under medical supervision until the primary outcome dose of 1.3 g/d BM protein was achieved. Basophil reactivity and milk protein-specific IgE binding were analyzed at the first round of BM OIT therapy (T0) and at 12 months of BM treatment.

RESULTS

In terms of the primary outcome, only 3 (21%) of 14 patients tolerated the 1.3 g/d BM dose. Although some patients initially progressed in BM OIT, 8 of 11 failed because of IgE-mediated reactions. Three did not complete the program because of non-IgE-mediated factors. An increase in challenge threshold to UM was noted in patients continuing until 12 months (P = .003), including those among whom reactions precluded continuation in the program. Patients (n = 3) who successfully reached maintenance had decreased milk-specific IgE reactivity. Furthermore, the mean difference at T0 between induced HM and UM percentages of CD203c expression was significantly lower in patients who successfully completed BM OIT than in those who did not (-11% vs 4.4%, P = .0002), which is consistent with their decreased clinical reactivity to BM.

CONCLUSIONS

Although use of hypoallergenic BM in OIT is a promising therapy, care must be taken before its administration in BM-reactive patients because of the risk for anaphylaxis and only limited increase in challenge threshold attained.

Better management of cow's milk allergy using a very low dose food challenge test: a retrospective study

BACKGROUND

Low dose reactive cow's milk (CM) allergic children are at high risk of persistent CM allergy and a positive oral food challenge (OFC). The present study aimed to evaluate if the results of a very low dose (VL) OFC with these children contributes to better management of CM allergy.

METHODS

We retrospectively reviewed subjects with CM allergy who underwent a VL OFC with 3 mL heated CM and had a previous allergic reaction to <25 mL heated CM in the 2 years before the OFC. Subjects who passed the OFC were defined as VL tolerant, and subjects who failed were defined as VL reactive. VL tolerant subjects increased the dose to 25 mL heated CM either during an OFC in our hospital or gradually at home.

RESULTS

Of the 83 subjects (median age, 4.3 years; range, 1.0-12.9 years) who were included, 41 (49.4%) were VL tolerant, and 42 (51.6%) were VL reactive. Thirty-nine VL reactive subjects had skin and/or respiratory symptoms during the OFC. Most reactions could be treated with an antihistamine and/or a nebulized β2 agonist. The VL tolerant subjects consumed 3 mL heated CM or 10 g butter. Within the year following the OFC, 18 VL tolerant subjects (45.0%), but none of the VL reactive subjects, were able to consume 25 mL heated CM (p < 0.001).

CONCLUSIONS

A VL OFC allows the management of some low dose reactive CM allergic children to change from complete avoidance to partial intake of CM.

Detection of relevant amounts of cow's milk protein in non-pre-packed bakery products sold as cow's milk-free

BACKGROUND

Currently, there is no mandatory labelling of allergens for non-pre-packed foods in the EU. Therefore, consumers with food allergy rely on voluntary information provided by the staff. The aim of this study was to characterize allergic reactions to non-pre-packed foods and to investigate whether staff in bakery shops were able to give advice regarding a safe product choice.

METHODS

Questionnaires were sent to 200 parents of children with a food allergy. Staff of 50 bakery shops were interviewed regarding selling non-pre-packed foods to food-allergic customers. Bakery products being recommended as 'cow's milk-free' were bought, and cow's milk protein levels were measured using ELISA.

RESULTS

A total of 104 of 200 questionnaires were returned. 25% of the children experienced an allergic reaction due to a non-pre-packed food from bakery shops and 20% from ice cream parlours. Sixty percent of the bakery staff reported serving food-allergic customers at least once a month, 24% once a week. Eighty four percent of the staff felt able to advise food-allergic consumers regarding a safe product choice. Seventy three 'cow's milk-free' products were sold in 44 bakery shops. Cow's milk could be detected in 43% of the bakery products, 21% contained >3 mg cow's milk protein per serving.

CONCLUSION

Staff in bakery shops felt confident about advising customers with food allergy. However, cow's milk was detectable in almost half of bakery products being sold as 'cow's milk-free'. Every fifth product contained quantities of cow's milk exceeding an amount where approximately 10% of cow's milk-allergic children will show clinical relevant symptoms.

Diagnosis, management, and investigational therapies for food allergies

Food allergies have increased in prevalence over the past 20 years, now becoming an important public health concern. Although there are no therapies currently available for routine clinical care, recent reports have indicated that immunotherapies targeting the mucosal immune system may be effective. Oral immunotherapy is conducted by administering small, increasing amounts of food allergen; it has shown promise for desensitizing individuals with peanut, egg, or milk allergies. Sublingual immunotherapy also desensitizes allergic patients to foods-2 major studies have examined the effects of sublingual immunotherapy in subjects with peanut allergies. We review the complex nature of IgE-mediated food allergies and the therapies being evaluated in clinical trials. We focus on the diagnosis and management of food allergies and investigational therapies.

Immunopathophysiology of food protein-induced enterocolitis syndrome

There is increasing recognition of the non-IgE-mediated gastrointestinal food allergy known as food protein-induced enterocolitis syndrome (FPIES), with several recent publications summarizing the clinical experience with FPIES in the United States, the United Kingdom, Europe, and Australia. Our understanding of the mechanisms linking food exposure to typical symptoms of vomiting, hypotension, and diarrhea has lagged far behind our understanding of the immune mechanisms of IgE-mediated food allergy. The goal of this overview is to summarize and critique the current state of knowledge of the immunology of FPIES and to identify major gaps in our knowledge that need to be addressed to make significant gains in developing therapies and prevention strategies for FPIES.

Anaphylaxis to food

This article provides a clinically focused review of food-induced anaphylaxis that includes epidemiology, risk factors, allergens, diagnosis, and management. Currently, there is no treatment for food allergy. Dietary avoidance and emergency preparedness are the cornerstones of management. Effective and safe therapies to reduce the risk of serious food-induced reactions are urgently needed, as are reliable biomarkers to predict severity.

The development of a standardised diet history tool to support the diagnosis of food allergy

The disparity between reported and diagnosed food allergy makes robust diagnosis imperative. The allergy-focussed history is an important starting point, but published literature on its efficacy is sparse. Using a structured approach to connect symptoms, suspected foods and dietary intake, a multi-disciplinary task force of the European Academy of Allergy and Clinical Immunology developed paediatric and adult diet history tools. Both tools are divided into stages using traffic light labelling (red, amber and green). The red stage requires the practitioner to gather relevant information on symptoms, atopic history, food triggers, foods eaten and nutritional issues. The amber stage facilitates interpretation of the responses to the red-stage questions, thus enabling the practitioner to prepare to move forward. The final green stage provides a summary template and test algorithm to support continuation down the diagnostic pathway. These tools will provide a standardised, practical approach to support food allergy diagnosis, ensuring that all relevant information is captured and interpreted in a robust manner. Future work is required to validate their use in diverse age groups, disease entities and in different countries, in order to account for differences in health care systems, food availability and dietary norms.

Diagnosis and treatment of pediatric food allergy: an update

The prevalence of pediatric food allergy and anaphylaxis has increased in the last decades, especially in westernized countries where this emerging phenomenon was marked as a "second wave" of the allergic epidemic. Over recent years great advances have been achieved in the field of in vitro allergy testing and component-resolved diagnosis has increasingly entered clinical practice. Testing for allergen components can contribute to a more precise diagnosis by discriminating primary from cross-reactive sensitizations and assessing the risk of severe allergic reactions.The basic concept of the management of food allergy in children is also changing. Avoidance of the offending food is still the mainstay for disease management, especially in primary health care settings, but it severely affects the patients' quality of life without reducing the risk of accidental allergic reactions. There is a growing body of evidence to show that specific oral tolerance induction can represent a promising treatment option for food allergic patients. In parallel, education of food allergic patients and their caregivers as well as physicians about anaphylaxis and its treatment is becoming recognized a fundamental need. International guidelines have recently integrated these new evidences and their broad application all over Europe represents the new challenge for food allergy specialists.

Food allergy: epidemiology and natural history

The prevalence of food allergy is rising for unclear reasons, with prevalence estimates in the developed world approaching 10%. Knowledge regarding the natural course of food allergies is important because it can aid the clinician in diagnosing food allergies and in determining when to consider evaluation for food allergy resolution. Many food allergies with onset in early childhood are outgrown later in childhood, although a minority of food allergy persists into adolescence and even adulthood. More research is needed to improve food allergy diagnosis, treatment, and prevention.

Chronic food protein-induced enterocolitis syndrome caused by cow's milk proteins passed through breast milk

We describe 2 cases of food protein-induced enterocolitis syndrome (FPIES) caused by cow's milk (CM) passed through breast milk. The onset in both cases was characterized by chronic symptoms (regurgitation, colic, diarrhea, failure to thrive); in one patient, two acute episodes due to the direct consumption of CM formula by the infant were also reported. The diagnosis of FPIES through breast milk can be easily overlooked, especially in milder cases. We also discuss some important issues concerning the general management of the disease. In conclusion, (1) the diagnosis of chronic FPIES should be taken into account even in exclusively breast-fed infants who present suggestive symptoms such as persistent regurgitation, small amounts of vomiting, lethargy, failure to thrive, dehydration, diarrhea (sometimes bloody) and abdominal distention. A 2-week maternal elimination diet should be considered even in apparently mild cases. (2) CM seems to be the most frequently reported culprit food. (3) In those cases in which acute FPIES is elicited by the direct consumption of the culprit food in breast-fed infants, maternal diet may be unrestricted.

Fifty years of allergy: 1965-2015

The last 50 years in allergy could almost be considered the first 50 years. Over this time period, we have witnessed the emergence of allergy as a subspecialty, have seen and continue to observe a tremendous change in prevalence of allergic disease and have gained insight into the mechanisms that underlie allergic predisposition and disease manifestation. We have improved the care of children with many forms of allergic disease and now sit poised to be able to alter the natural history of allergic disease with the use of specific immunotherapy. There is much left to do in the next 50 years including understanding what underlies both the predisposition to atopic disease and its natural resolution and identifying the environmental cofactors involved in the 'allergic epidemic' and therefore targets for effective primary prevention.

Novel approaches to food allergy

Food allergies have increased in recent decades. However, they cannot be effectively treated by the current management, which is limited to the identification and avoidance of foods that induce allergies and to the use of medicines for symptoms relief. To meet the medical need of prevention and cure of food allergies, several therapeutic strategies are under investigation. Some newly developed biologics such as anti-IgE antibody and anti-interleukin (IL)-5 antibody directed against significant molecules in the allergic process have shown their potential for the treatment of food allergies. Allergen-specific immunotherapy is the therapy that induces immune tolerance and may reduce the need for conventional medication, severity of allergic symptoms and eliminate hypersensitivity. In this article, clinical studies of immunotherapy via subcutaneous, oral, sublingual, and epicutaneous routes are extensively reviewed for their safety and effectiveness on various food allergies. In addition, to reduce the risk of anaphylaxis and increase toleragenic immunity, many studies are focusing on the modification of traditional allergens used for immunotherapy. Moreover, a Chinese herbal formulation with potential anti-allergic effects is being evaluated for its efficacy in patients with peanut allergy. Although more studies are needed, accumulated data of current studies represent compelling evidence of curative effects of some strategies and give a hope that food allergies are likely to be successfully treated in the future.

BSACI guideline for the diagnosis and management of cow's milk allergy

This guideline advises on the management of patients with cow's milk allergy. Cow's milk allergy presents in the first year of life with estimated population prevalence between 2% and 3%. The clinical manifestations of cow's milk allergy are very variable in type and severity making it the most difficult food allergy to diagnose. A careful age- and disease-specific history with relevant allergy tests including detection of milk-specific IgE (by skin prick test or serum assay), diagnostic elimination diet, and oral challenge will aid in diagnosis in most cases. Treatment is advice on cow's milk avoidance and suitable substitute milks. Cow's milk allergy often resolves. Reintroduction can be achieved by the graded exposure, either at home or supervised in hospital depending on severity, using a milk ladder. Where cow's milk allergy persists, novel treatment options may include oral tolerance induction, although most authors do not currently recommend it for routine clinical practice. Cow's milk allergy must be distinguished from primary lactose intolerance. 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 clinicians in secondary and tertiary care. The recommendations are evidence based, but where evidence is lacking the panel of experts in the committee reached consensus. Grades of recommendation are shown throughout. The document encompasses epidemiology, natural history, clinical presentations, diagnosis, and treatment.

Effect of heat treatment on milk and egg proteins allergenicity

BACKGROUND

Heating destroys many conformational epitopes and reduces allergenicity of some foods. IgE-epitope binding has been shown to be different among patients who outgrew their cow's milk or hen's egg allergy and those who did not. A significant proportion of milk- or egg-allergic children are tolerant to these foods in their baked forms. We sought to explore the effects of heating on milk and egg proteins and to evaluate for differences in immunolabeling among children with regard to reactivity to heated milk or egg.

METHODS

Sera from participants in clinical dietary intervention trials were utilized. Milk and egg samples were variably heated and prepared (at times within a wheat matrix). Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), protein transfer, and Western blot were completed.

RESULTS

Sera from 20 milk-allergic and 24 egg-allergic children were utilized. Gel electrophoresis showed strongly staining casein bands that persisted for up to 60 min of heating. In contrast, β-lactoglobulin and α-lactalbumin bands became progressively weaker with increasing heating times, with no detectable β-lactoglobulin after 15-20 min of heating. The ovalbumin band became progressively weaker, whereas ovomucoid remained stable after 25 min of heating. Immunolabeling revealed that all heated milk-reactive children possessed IgE antibodies that bound the casein fraction regardless of heating time. Presence of wheat during heating resulted in decreased IgE antibody binding to milk and egg white proteins.

CONCLUSION

Heating has a different effect on whey and caseins in cow's milk and ovalbumin and ovomucoid in hen's egg white. The effect of heat on protein allergenicity is affected by the temperature and duration, along with the presence of wheat.

Optimizing the diagnosis of food allergy

Accurately diagnosing a patient with a possible food allergy is important to avoid unnecessary dietary restrictions and prevent life-threatening reactions. Routine testing modalities have limited accuracy, and an oral food challenge is often required to make a definitive diagnosis. Given that they are labor intensive and risk inducing an allergic reaction, several alternative diagnostic modalities have been investigated. Testing for IgE antibodies to particular protein components in foods has shown promise to improve diagnostics and has entered clinical practice. Additional modalities show potential, including epitope binding, T-cell studies, and basophil activation.

Butter Tolerance in Children Allergic to Cow's Milk

We performed an oral food challenge (OFC) with 10 g of butter (equivalent of 2.9 mL cow's milk) and 25-mL heated cow's milk for 68 children with cow's milk-allergy. Thirty-eight children reacted only to heated cow's milk. Twenty-four children reacted to neither heated milk nor butter. Thirty-eight (86.4%) of 44 patients with positive results to the OFC for heated milk could safely tolerate butter. It is highly likely that even children with cow's milk-allergy who show positive results to an OFC for heated milk can consume butter. The milk-specific IgE value indicative of a negative predictive value of over 95% was 17.8 kUA/L, and patients with low milk-specific IgE values may be able to safely consume butter. Including butter in the diets of patients with milk-allergy after a butter challenge may improve quality of life.

The role of casein-specific IgA and TGF-β in children with food protein-induced enterocolitis syndrome to milk

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a gastrointestinal hypersensitivity disorder with a poorly understood pathophysiology and no biomarkers to aid in diagnosis.

OBJECTIVE

To investigate humoral and cellular responses to casein in children with milk-FPIES, including the role of casein-specific (cs) IgA and T-cell mediated TGF-β responses.

PATIENTS AND METHODS

Thirty-one children previously diagnosed with milk-FPIES were challenged with milk. Twelve age-matched children with FPIES to other foods and 6 milk-tolerant children without a history of FPIES were used as controls. Casein-specific IgE, IgG, IgG4, and IgA were measured in serum and TGF-β levels in supernatants of casein-stimulated PBMCs.

RESULT

Twenty-six children with milk-FPIES reacted (active milk-FPIES) and five tolerated milk (milk-FPIES resolved) during food challenge. All of them had significantly lower levels of csIgG, csIgG4, and csIgA than control children (p-value<0.001). There were no TGF-β responses in supernatants of active milk-FPIES children.

CONCLUSION

Children with milk-FPIES have low levels of csIgG, csIgG4, and csIgA. In particular, children with active FPIES to cow's milk have deficient T-cell mediated TGF-β responses to casein, rendering TGF-β a promising biomarker in identifying children who are likely to experience FPIES reactions to this allergen. Prospective studies are needed to validate these findings, elucidate their role in FPIES pathophysiology, and establish the diagnostic utility of TGF-β in milk-induced FPIES.

Food allergy: a practice parameter update-2014

This parameter was developed by the Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma & Immunology (JCAAI). The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Food Allergy: A practice parameter update-2014." This is a complete and comprehensive document at the current time. The medical environment is a changing one, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, ACAAI, and JCAAI. These parameters are not designed for use by pharmaceutical companies in drug promotion.

Safety and clinical predictors of reacting to extensively heated cow's milk challenge in cow's milk-allergic children

BACKGROUND

Many children with IgE-mediated allergy to cow's milk (CM) can tolerate CM in baked foods.

OBJECTIVE

To define the clinical characteristics and severity of reactions to baked CM in children with CM allergy (CMA) at an oral food challenge (OFC).

METHODS

Children with CMA presenting to a tertiary clinic from 2010 through 2013 with complete dietary CM avoidance were offered a baked CM OFC. Challenges were performed with incremental dosages to a total of 1 baked muffin.

RESULTS

Seventy children with CMA underwent a baked CM OFC. Fifty-one children (73%) passed the OFC and successfully incorporated baked CM into their diet. Nineteen children (27%) reacted to their challenge. Of reactors, 4 (21%) developed anaphylaxis and required intramuscular adrenalin. Predictors of clinical reactivity to baked CM were asthma, asthma requiring preventer therapy, IgE-mediated clinical reactions to more than 3 food groups, and those with a history of CM anaphylaxis.

CONCLUSION

This study identified factors that were predictors of clinical reactivity to baked CM in this cohort of children with CMA. These risk factors do not represent contradictions to a baked CM challenge but may allow for risk stratification of challenges. Given the potential for anaphylaxis, an OFC to baked CM should be done under medical supervision in those children with CMA who have been strictly avoiding all CM.

Effect of raw milk on allergic responses in a murine model of gastrointestinal allergy

Epidemiological studies have shown an association between the consumption of raw farm milk and reduced incidence of allergy. In the present study, we fed untreated raw milk, gamma-sterilised milk, heat-treated milk or water to mice and compared their responses to allergen exposure and challenge treatment in a mouse model of gastrointestinal allergy. From weaning (3 weeks old), groups of BALB/c female mice (n 8) received raw milk, gamma-sterilised milk, heated milk or water via drink bottles, with the control group receiving water. All mice were fed a standard (dairy protein-free) rodent diet. At 6 and 8 weeks, groups were given intra-peritoneal injections with ovalbumin (OVA)/alum to sensitise them to the antigen. Controls were sham immunised. At week 10, mice were fasted and challenged four times on alternate days by intra-gastric administration with 50 mg OVA or saline. Levels of bacteria and milk proteins were assessed in milk samples. Mouse serum levels of specific IgE, IgG1 and IgG2a antibodies and mouse mast cell protease-1 (MMCP-1) were determined. Cytokine responses to 48 h activation with OVA were measured in cultured splenocytes from mice. Sterilised and heated milks contained no viable bacteria and reduced detectable levels of many milk proteins, in contrast to raw milk. Mice drinking raw milk had highest serum MMCP-1 and specific-OVA IgE responses. Cultured splenocytes from OVA-primed mice produced similar levels of IL-4 in response to the antigen; however, IL-10 levels were highest from mice drinking raw milk. Overall, the present study adds to the evidence that consuming different types of milk can affect allergic responses to a non-related dietary antigen.

Oral immunotherapy for food allergy, ready for prime time? Heated egg and milk

Cow's milk and hen's egg allergies are two of the most common food allergies that affect children, with an estimated prevalence of 2-3 % each. Persistence of food allergy into late teen years and adulthood is being increasingly recognized, possibly due to strict avoidance practices. Heating has been known to alter food allergenicity, and the majority of milk- and egg-allergic patients tolerate heated forms of those foods. Heated milk and heated egg have been increasingly studied as oral immunotherapy (OIT) for treatment of milk and egg allergy. While heated milk and heated egg have been shown to be safe in selected milk- and egg-allergic cohorts, larger studies are needed to predict which patients are optimal candidates for this strategy and to further clarify whether ingestion of heated milk or heated egg truly accelerates the onset of clinical tolerance to unheated forms of these foods.

State of the art on food allergen immunotherapy: oral, sublingual, and epicutaneous

IgE-mediated food allergy is a global health problem that affects millions of persons and affects every aspect of life for the patient. Developing effective treatment strategies to augment current practice standards of strict dietary avoidance of antigens and availability of self-injectable epinephrine has been a major focus of research teams, advocacy groups, funding agencies, and patients and their families. Significant progress has been made through the development of allergen-specific immunotherapy encompassing 3 major forms of treatment: oral, sublingual, and epicutaneous immunotherapy. These therapies are in various stages of clinical investigation, with some successes noted in clinical outcomes and modulation of immune mechanisms toward effective therapy. Here we review recent progress and areas of concern for the role of these forms of immunotherapy as an emerging treatment for food allergy.

Future Therapies for IgE-Mediated Food Allergy

Food allergy is prevalent, affecting approximately 4-8% of children. There is no currently approved treatment for food allergy, and while strict allergen avoidance is recommended it is difficult to achieve and therefore accidental exposures and reactions are common. There is an urgent need for the development of therapeutic approaches that will improve the health and quality of life of children with food allergy. The majority of current clinical research focus is on specific food allergen immunotherapy through oral, sublingual, or epicutaneous routes. Pre-clinical research has focused on making improvements to the safety and efficacy of allergen immunotherapy through modifications of allergen structure and addition of immuno-modulatory factors. The number of novel therapeutics for food allergy reaching the level of clinical trials remains disappointingly low, and there is a need for an expansion of pre-clinical research to provide safe, practical and novel approaches to the treatment of food allergy.

Allergenic properties and differential response of walnut subjected to processing treatments

The aim of this study was to investigate changes in walnut allergenicity after processing treatments by in vitro techniques and physiologically relevant assays. The allergenicity of walnuts subjected to high hydrostatic pressure and thermal/pressure treatments was evaluated by IgE-immunoblot and antibodies against walnut major allergen Jug r 4. The ability of processed walnut to cross-link IgE on effector cells was evaluated using a rat basophil leukaemia cell line and by skin prick testing. Susceptibility to gastric and duodenal digestion was also evaluated. The results showed that walnuts subjected to pressure treatment at 256 kPa, 138 °C, were able to diminish the IgE cross-linking capacity on effector cells more efficiently than high pressure treated walnuts. IgE immunoblot confirmed these results. Moreover, higher susceptibility to digestion of pressure treated walnut proteins was observed. The use of processed walnuts with decreased IgE binding capacity could be a potential strategy for walnut tolerance induction.