Position document: IgE-mediated cow's milk allergy

Dairy, Plant, and Novel Proteins: Scientific and Technological Aspects

Alternative proteins have gained popularity as consumers look for foods that are healthy, nutritious, and sustainable. Plant proteins, precision fermentation-derived proteins, cell-cultured proteins, algal proteins, and mycoproteins are the major types of alternative proteins that have emerged in recent years. This review addresses the major alternative-protein categories and reviews their definitions, current market statuses, production methods, and regulations in different countries, safety assessments, nutrition statuses, functionalities and applications, and, finally, sensory properties and consumer perception. Knowledge relative to traditional dairy proteins is also addressed. Opportunities and challenges associated with these proteins are also discussed. Future research directions are proposed to better understand these technologies and to develop consumer-acceptable final products.

Higher Potential Sensitization of Cow αS1-Casein over Goat αS1-Casein in a Mouse Model due to Enhanced Dendritic Cell Uptake and Activation

Cow's milk allergy is a common food allergy, with the milk protein αS1-casein being a major allergen. This study aimed to investigate differences in sensitization between cow and goat αS1-CN. Cow and goat αS1-CN were labeled with fluorescent dyes and given to mice sensitized with cholera toxin adjuvant. Both proteins reached immune organs, suggesting no major difference in digestion. However, compared with goat αS1-CN, cow αS1-CN is more readily taken up by dendritic cells, inducing dendritic cell maturation. Furthermore, cow αS1-CN can more effectively induce the generation of Th2 cells, leading to a higher production of specific IgE. In a Caco-2/RBL-2H3 cell model, cow αS1-CN caused more mast cell degranulation and loss of epithelial barrier integrity than goat αS1-CN. In summary, this study found differences in immune responses between cow and goat milk αS1-CN. Cow αS1-CN elicited stronger dendritic cell and Th2 responses, leading to increased mast cell degranulation.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) guidelines update - X - Breastfeeding a baby with cow's milk allergy

Cow's milk allergy is rare in exclusively breastfed infants. To support the continuation of breastfeeding an infant after diagnosis with a cow's milk allergy, it is critical to examine the evidence for and against any form of cow's milk elimination diet for lactating mothers. In this narrative review, we highlight the lack of high-quality evidence, hence subsequent controversy, regarding whether the minuscule quantities of cow's milk proteins detectable in human milk cause infant cow's milk allergy symptoms. Current clinical practice recommendations advise a 2-4 week trial of maternal cow's milk dietary elimination for: a) IgE-mediated cow's milk allergy only if the infant is symptomatic on breastfeeding alone; b) non-IgE-mediated associated symptoms only if the history and examination strongly suggest cow's milk allergy; and c) infants with moderate to severe eczema/atopic dermatitis, unresponsive to topical steroids and sensitized to cow's milk protein. There should be a clear plan for home reintroduction of cow's milk into the maternal diet for a period of 1 week to determine that the cow's milk elimination is responsible for resolution of symptoms, and then subsequent reoccurrence of infant symptoms upon maternal cow's milk reintroduction. The evidence base to support the use of maternal cow's milk avoidance for the treatment of a breastfed infant with cow's milk allergy is of limited strength due to a lack of high-quality, adequately powered, randomised controlled trials. It is important to consider the consequences of maternal cow's milk avoidance on reducing immune enhancing factors in breast milk, as well as the potential nutritional and quality of life impacts on the mother. Referral to a dietitian is advised for dietary education, along with calcium and vitamin D supplementation according to local recommendations, and a maternal substitute milk should be advised. However, for most breastfed infants with cow's milk allergy maternal cow's milk dietary elimination will not be required, and active support of the mother to continue breastfeeding is essential.

Update on In Vitro Diagnostic Tools and Treatments for Food Allergies

Food allergy (FA) is an adverse immunological reaction to a specific food that can trigger a wide range of symptoms from mild to life-threatening. This adverse reaction is caused by different immunological mechanisms, such as IgE-mediated, non-IgE-mediated and mixed IgE-mediated reactions. Its epidemiology has had a significant increase in the last decade, more so in developed countries. It is estimated that approximately 2 to 10% of the world's population has FA and this number appears to be increasing and also affecting more children. The diagnosis can be complex and requires the combination of different tests to establish an accurate diagnosis. However, the treatment of FA is based on avoiding the intake of the specific allergenic food, thus being very difficult at times and also controlling the symptoms in case of accidental exposure. Currently, there are other immunomodulatory treatments such as specific allergen immunotherapy or more innovative treatments that can induce a tolerance response. It is important to mention that research in this field is ongoing and clinical trials are underway to assess the safety and efficacy of these different immunotherapy approaches, new treatment pathways are being used to target and promote the tolerance response. In this review, we describe the new in vitro diagnostic tools and therapeutic treatments to show the latest advances in FA management. We conclude that although significant advances have been made to improve therapies and diagnostic tools for FA, there is an urgent need to standardize both so that, in their totality, they help to improve the management of FA.

Recent advances in selective allergies to mammalian milk proteins not associated with Cow's Milk Proteins Allergy

Cow's milk proteins allergy (CMA) is an atypical immune system response to cow's milk and dairy products. It's one of the most common food allergies in children affecting 8% of the total pediatric population pediatric population. This comprehensive review examines recent studies in CMA, especially regarding mammalian milk allergies such as goat's, sheep's, buffalo's, camel's, mare's and donkey's milk allergies in order to increase awareness of these selective allergies and to reduce allergy risks for those who have them. The consumption of other mammalian milk types is not recommended because of the significant homology between milk proteins from cow, sheep, goat and buffalo resulting in clinical cross-reactivity. However, camel's, mare's or donkey's milk may be tolerated by some allergic patients. Selective mammalian milk allergies are unusual and rare disorders characterized by severe symptoms including angio-oedema, urticaria, respiratory manifestations and anaphylaxis. Based on the reported allergic cases, cheese products including Ricotta, Romano, Pecorino and Mozzarella, are considered as the most common source of allergens especially in goat's, sheep's and buffalo's milk allergies, while the major allergens in donkey's and mare's milk seems to be whey proteins including lysozyme, α-lactalbumin and β-lactogloblin due to the low casein/whey proteins ratio in equine's milk.

Preparation of Hypoallergenic Whey Protein Hydrolysate by a Mixture of Alcalase and Prozyme and Evaluation of Its Digestibility and Immunoregulatory Properties

Whey protein (WP) has nutritional value, but the presence of β-lactoglobulin (β-LG) and α-lactalbumin (α-LA) cause allergic reactions. In this study, hypoallergenic whey protein hydrolyate (HWPH) was prepared by decomposing β-LG and α-LA of WP using exo- and endo-type proteases. The enzyme mixing ratio and reaction conditions were optimized using response surface methodology (RSM). Degradation of α-LA and β-LG was confirmed through gel electrophoresis, and digestion, and absorption rate, and immunostimulatory response were measured using in vitro and in vivo systems. Through RSM analysis, the optimal hydrolysis conditions for degradation of α-LA and β-LG included a 1:1 mixture of Alcalase and Prozyme reacted for 10 h at a 1.0% enzyme concentration relative to substrate. The molecular weight of HWPH was <5 kDa, and leucine was the prominent free amino acid. Both in vitro and in vivo tests showed that digestibility and intestinal permeability were higher in HWPH than in WP. In BALB/c mice, as compared to WP, HWPH reduced allergic reactions by inducing elevated Type 1/Type 2 helper T cell ratio in the blood, splenocytes, and small intestine. Thus, HWPH may be utilized in a variety of low allergenicity products intended for infants, adults, and the elderly.

One-food versus six-food elimination diet therapy for the treatment of eosinophilic oesophagitis: a multicentre, randomised, open-label trial

BACKGROUND

Empirical elimination diets are effective for achieving histological remission in eosinophilic oesophagitis, but randomised trials comparing diet therapies are lacking. We aimed to compare a six-food elimination diet (6FED) with a one-food elimination diet (1FED) for the treatment of adults with eosinophilic oesophagitis.

METHODS

We conducted a multicentre, randomised, open-label trial across ten sites of the Consortium of Eosinophilic Gastrointestinal Disease Researchers in the USA. Adults aged 18-60 years with active, symptomatic eosinophilic oesophagitis were centrally randomly allocated (1:1; block size of four) to 1FED (animal milk) or 6FED (animal milk, wheat, egg, soy, fish and shellfish, and peanut and tree nuts) for 6 weeks. Randomisation was stratified by age, enrolling site, and gender. The primary endpoint was the proportion of patients with histological remission (peak oesophageal count <15 eosinophils per high-power field [eos/hpf]). Key secondary endpoints were the proportions with complete histological remission (peak count ≤1 eos/hpf) and partial remission (peak counts ≤10 and ≤6 eos/hpf) and changes from baseline in peak eosinophil count and scores on the Eosinophilic Esophagitis Histology Scoring System (EoEHSS), Eosinophilic Esophagitis Endoscopic Reference Score (EREFS), Eosinophilic Esophagitis Activity Index (EEsAI), and quality of life (Adult Eosinophilic Esophagitis Quality-of-Life and Patient Reported Outcome Measurement Information System Global Health questionnaires). Individuals without histological response to 1FED could proceed to 6FED, and those without histological response to 6FED could proceed to swallowed topical fluticasone propionate 880 μg twice per day (with unrestricted diet), for 6 weeks. Histological remission after switching therapy was assessed as a secondary endpoint. Efficacy and safety analyses were done in the intention-to-treat (ITT) population. This trial is registered on ClinicalTrials.gov, NCT02778867, and is completed.

FINDINGS

Between May 23, 2016, and March 6, 2019, 129 patients (70 [54%] men and 59 [46%] women; mean age 37·0 years [SD 10·3]) were enrolled, randomly assigned to 1FED (n=67) or 6FED (n=62), and included in the ITT population. At 6 weeks, 25 (40%) of 62 patients in the 6FED group had histological remission compared with 23 (34%) of 67 in the 1FED group (difference 6% [95% CI -11 to 23]; p=0·58). We found no significant difference between the groups at stricter thresholds for partial remission (≤10 eos/hpf, difference 7% [-9 to 24], p=0·46; ≤6 eos/hpf, 14% [-0 to 29], p=0·069); the proportion with complete remission was significantly higher in the 6FED group than in the 1FED group (difference 13% [2 to 25]; p=0·031). Peak eosinophil counts decreased in both groups (geometric mean ratio 0·72 [0·43 to 1·20]; p=0·21). For 6FED versus 1FED, mean changes from baseline in EoEHSS (-0·23 vs -0·15; difference -0·08 [-0·21 to 0·05]; p=0·23), EREFS (-1·0 vs -0·6; difference -0·4 [-1·1 to 0·3]; p=0·28), and EEsAI (-8·2 vs -3·0; difference -5·2 [-11·2 to 0·8]; p=0·091) were not significantly different. Changes in quality-of-life scores were small and similar between the groups. No adverse event was observed in more than 5% of patients in either diet group. For patients without histological response to 1FED who proceeded to 6FED, nine (43%) of 21 reached histological remission; for patients without histological response to 6FED who proceeded to fluticasone propionate, nine (82%) of 11 reached histological remission.

INTERPRETATION

Histological remission rates and improvements in histological and endoscopic features were similar after 1FED and 6FED in adults with eosinophilic oesophagitis. 6FED had efficacy in just less than half of 1FED non-responders and steroids had efficacy in most 6FED non-responders. Our findings indicate that eliminating animal milk alone is an acceptable initial dietary therapy for eosinophilic oesophagitis.

FUNDING

US National Institutes of Health.

Probiotic Bacteria from Human Milk Can Alleviate Oral Bovine Casein Sensitization in Juvenile Wistar Rats

This study aims to see if probiotic bacteria from human milk could ameliorate oral cow's milk sensitization. The probiotic potential of the SL42 strain isolated from the milk of a healthy young mother was first determined. Rats were then randomly gavaged with cow's milk casein without an adjuvant or assigned to the control group. Each group was further subdivided into three groups, with each receiving only Limosilactobacillus reuteri DSM 17938, SL42, or a phosphate-buffered saline solution. Body weight, temperature, eosinophils, serum milk casein-specific IgE (CAS-IgE), histamine, and serum S100A8/A9 and inflammatory cytokine concentrations were measured. The animals were sacrificed after 59 days; histological sections were prepared, and the spleen or thymus weights, as well as the diversity of the gut microbiota, were measured. On days 1 and 59, SL42 abridged systemic allergic responses to casein by dropping histamine levels (25.7%), CAS-specific IgE levels (53.6%), eosinophil numbers (17%), S100A8/9 (18.7%), and cytokine concentrations (25.4-48.5%). Analyses of histological sections of the jejunum confirmed the protective effect of probiotic bacteria in the CAS-challenged groups. Lactic acid bacteria and Clostridia species were also increased in all probiotic-treated groups. These findings suggest that probiotics derived from human milk could be used to alleviate cow's milk casein allergy.

[Prevalence of cow´s milk allergy and lactose intolerance among Mexican late adolescents]

OBJECTIVE

To determine the prevalence of cow´s milk allergy and lactose intolerance in a sample of late adolescents.

METHODS

Through a population-based study, data corresponding to students with aged 15 to 18 years were analyzed.

RESULTS

A total of 1992 adolescents was analized. The prevalence of cow´s milk allergy was 1.4% (95% CI: 0.2% to 0.8%) and the prevalence of lactose intolerance was 0.5% (95% CI: 0.2% to 0.8%). Adolescents with cow´s milk allergy had fewer gastrointestinal symptoms (p = 0.036), but more skin (p < 0.001) and respiratory (p = 0.028) ailments than adolescents with lactose intolerance.

CONCLUSIONS

The manifestations associated with cow's milk consumption in late adolescents seem to correspond mainly to cow´s milk allergy than to lactose intolerance.

The use of amino acid formulas in pediatric patients with allergy to cow's milk proteins: Recommendations from a group of experts

One of the most common food allergies in children is cow's milk allergy (CMA). In breast-fed infants with CMA, the mother is encouraged to avoid dairy products. If this is not possible, or in formula fed infants, use of hypoallergenic replacement formulas such as extensively hydrolyzed formulas (EHF) is recommended. However, in ∼5% of patients EHFs are not tolerated and/or allergy symptoms can persist. When EHFs are ineffective and in severe forms of CMA, amino acid-based formulas (AAF) should be considered. Six pediatric gastroenterologists with extensive experience in food allergy management reviewed scientific publications and international clinical practice guidelines to provide practical recommendations on AAF. The guidelines reviewed had discrepancies and ambiguities around the specific indications for using formulas as a milk substitute. The panel recommends AAFs as the first therapeutic option in anaphylaxis due to CMA, in acute and chronic severe food protein-induced enterocolitis syndrome, in CMA associated with multiple food allergy, and in cases of eosinophilic esophagitis not responding to an extended exclusion diet or not eating solids. The main benefit of AAF is its absence of residual allergenicity, making it a safe treatment option in severe CMA patients who do not tolerate or respond to an EHF.

Hydrolyzed rice formula for dietary management of infants with cow's milk allergy

Background

Allergic diseases are increasing globally and are a significant public health challenge, especially in children. Cow's milk allergy (CMA) is one of the most common food allergies in early childhood. When CMA is diagnosed and exclusive breastfeeding is not possible, current guidelines recommend extensively hydrolyzed formulas (eHF) or amino acid-based formulas (AAF), depending on the diagnosis and severity of symptoms. Hydrolyzed rice formulas (HRF) are considered an alternative to eHF and AAF where available.

Objectives & methods

We aimed to understand how HRF are being used and their position in the management of CMA, and to generate consensus on indications for use. Two virtual roundtables of international healthcare experts in pediatric food allergy focused on HRF were convened in May and October 2021. Experts provided multiple perspectives due to different specialties, locations, healthcare settings, and availability of HRF. Following discussion of international CMA guidelines and HRF use, identification of challenges along the diagnosis and treatment pathway, and translation of guidelines into clinical practice, an expert consensus on the use of HRF for CMA was developed. This involved repeated voting followed by statement amendment to reach 100% agreement. This publication summarizes insights from these meetings.

Results

There was 100% agreement on all 8 statements: (1) While breastmilk is the best source of nutrition for infants with CMA, when breastfeeding is not possible, a hypoallergenic formula can be used; (2) Per definition, a HRF is cow's milk protein-free; (3) A minority of infants with immunoglobulin (Ig)E-mediated CMA react to eHF due to residual cow's milk protein; (4) More infants with non-IgE-mediated CMA than IgE-mediated CMA react to eHF likely due to residual cow's milk protein; (5) When a diagnostic elimination diet is indicated, HRF can be used; (6) A HRF can be recommended as a first-line option for CMA, where available, as outlined in the Diagnosis and Rationale for Action against Cow's Milk Allergy guidelines; (7) HRFs have proven hypoallergenicity and are suitable for the dietary management of CMA; (8) HRFs have been shown to support growth in infants with CMA, similar to other hypoallergenic formulas. Participants recommend healthcare professionals take these statements as guidance to use HRF in clinical practice. Based on efficacy and growth evidence, the experts found HRF a suitable option for the dietary management of CMA.

Conclusion

HRF can be recommended as a first-line alternative to cow's milk-based eHF or AAF, where available, in the dietary management of CMA.

Alteration of the allergenicity of cow's milk proteins using different food processing modifications

Milk is an essential source of protein for infants and young children. At the same time, cow's milk is also one of the most common allergenic foods causing food allergies in children. Recently, cow's milk allergy (CMA) has become a common public health issue worldwide. Modern food processing technologies have been developed to reduce the allergenicity of milk proteins and improve the quality of life of patients with CMA. In this review, we summarize the main allergens in cow's milk, and introduce the recent findings on CMA responses. Moreover, the reduced effects and underlying mechanisms of different food processing techniques (such as heating, high pressure, γ-ray irradiation, ultrasound irradiation, hydrolysis, glycosylation, etc.) on the allergenicity of cow's milk proteins, and the application of processed cow's milk in clinical studies, are discussed. In addition, we describe the changes of nutritional value in cow's milk treated by different food processing technologies. This review provides an in-depth understanding of the allergenicity reduction of cow's milk proteins by various food processing techniques.

Consensus document on the primary prevention of cow's milk protein allergy in infants aged less than 7 days

INTRODUCTION

Cow's milk protein allergy (CMPA) is the most frequent food allergy in the first year of life. There is no clear consensus regarding its prevention. A recommendation to avoid CMP in the first week of life as a preventive measure in all infants, regardless of their atopic risk, has recently been published. The purpose of this document is to issue a recommendation on the use of extensively hydrolyzed CMP formulas in the first week of life for the primary prevention of CMPA.

METHODS

A group of experts was formed with members proposed by the Spanish Association of Pediatrics (AEP), the Spanish Society of Clinical Immunology and Allergology and Pediatric Asthma (SEICAAP), the Spanish Society of Pediatric Gastroenterology, Hepatology and Nutrition (SEGHNP) and the Spanish Society of Neonatology (SENEO). The group conducted a critical review of the evidence on the subject published in the last 10 years.

RESULTS

The search yielded 72 studies, of which 66 were rejected for not meeting the inclusion criteria. The final review included 6 documents: 3 clinical trials and 3 systematic reviews, 2 of them with meta-analysis. There was no evidence of a statistically significant reduction in the incidence of CMPA in the infants who received hypoallergenic formulae or exclusive breastfeeding.

CONCLUSION

Based on the current evidence, it is not possible to draw clear conclusions about the effect of avoiding CMP in the first week of life for prevention of CMPA. Although there are data that suggest a certain beneficial effect of avoiding CMPA in atopic risk infants, these results are not conclusive enough to extend the recommendation to the general population.

Disparities in Patient- and Family-Centered Care Among Children With Health Conditions

The objective of this study was to estimate and compare the prevalence of patient- and family-centered cae (PFCC) received by children in the United States (US) with chronic and developmental health conditions and determine associations between the presence of the conditions and parents’ perceptions of PFCC after controlling for covariates. Linked data from the 2012–2016 National Health Interview Survey (NHIS) and 2013–2017 Medical Expenditure Panel Survey (MEPS) (n = 7,835) were tested using crude and adjusted logistic regression procedures. Parents of children with developmental delays had 32% lower odds (95% CI = 0.51–0.90) of reporting their healthcare provider always exhibited all PFCC qualities. Parents of children with allergies and developmental delays had 26% (95% CI = 0.58–0.95) and 42% (95% CI = 0.42–0.80) lower odds of reporting their provider always listened carefully compared to parents whose children did not. Findings demonstrate the importance of continuous training for providers to tailor communication for families who have children with health conditions.

Consensus on the diagnosis and treatment of cow's milk protein allergy of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition

Cow's milk protein allergy (CMPA) is the most frequent cause of food allergy in the first months of life. Despite the fact that there are different guidelines and recommendations on the management of children with CMPA, there continues to be great variability in diagnostic and therapeutic criteria in Latin America. The Food Allergy Working Group of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition summoned a group of Latin American experts to reach a consensus and formulate a document to unify diagnostic and therapeutic criteria for CMPA. Three teams were formed, each with a coordinator, and the members of each team developed a series of statements for their corresponding module: a) clinical manifestations and diagnosis; b) diagnostic tools, and c) treatment. A search of the medical literature was carried out to support the information presented in each module and 28 statements were then selected. The statements were discussed, after which they were evaluated by all the experts, utilizing the Delphi method. Their opinions on statement agreement or disagreement were anonymously issued. The final statements selected were those with above 75% agreement and their corresponding recommendations were formulated, resulting in the document presented herein.

Maillard Reaction Induced Changes in Allergenicity of Food

Food allergy is increasing in prevalence, posing aheavier social and financial burden. At present, there is still no widely accepted treatment for it. Methods to reduce or eliminate the allergenicity of trigger foods are urgently needed. Technological processing contributes to producing some hypoallergenic foods. Among the processing methods, the Maillard reaction (MR) is popular because neither special chemical materials nor sophisticated equipment is needed. MR may affect the allergenicity of proteins by disrupting the conformational epitope, disclosing the hidden epitope, masking the linear epitope, and/or forming a new epitope. Changes in the allergenicity of foods after processing are affected by various factors, such as the characteristics of the allergen, the processing parameters, and the processing matrix, and they are therefore variable and difficult to predict. This paper reviews the effects of MR on the allergenicity of each allergen group from common allergenic foods.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow’s Milk Allergy (DRACMA) Guidelines update – IV – A quality appraisal with the AGREE II instrument

Background

Since the publication of The World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guidelines in 2010, a number of other guidelines, expert opinions, and position papers relating to the management of cow's milk allergy (CMA) have been published. We aimed to systematically review the quality of the guidelines on CMA diagnosis and management in children and/or adults published between 2010 and 2020.

Methods

The MEDLINE, EMBASE, ISI Web of Science, World Health Organization Global Index Medicus, and Turning Research into Practice databases as well as website guideline repositories were searched from January 2010 until May 2020. Any clinical practice recommendations and/or guidelines focusing on the diagnosis and management of CMA in children and/or adults developed or endorsed by professional scientific societies or organizations were included. The guidelines were evaluated using the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool, a 23-item tool organized within 6 domains and 2 global rating items.

Results

We included 12 guidelines; 8 were developed by national and 4 by international organizations. The quality scores for each domain varied: of all domains, the clarity of presentation domain had the highest median score (92%; Q1-Q3 81–100%), whereas rigor of development had the lowest median score (30%; Q1-Q3 15–67%). The median scores (Q1-Q3) for individual domains were as follows: scope and purpose 82% (70–99%), stakeholder involvement 63% (21–79%), rigor of development 30% (15–67%), clarity of presentation 92% (81–100%), applicability 68% (57–75%), and editorial independence 75% (69–100%). The median overall score was 70% (58–89%). Only 1 guideline (from the National Institute for Health and Care Excellence [NICE]) achieved top ratings (100%) in five domains and the overall score. Three guidelines (from the NICE, the British Society for Allergy & Clinical Immunology [BSACI] and WAO) achieved the highest ratings (100%) in at least 3 domains and the overall score.

Conclusion

The majority of identified guidelines were of good or very good quality. However, the weakest point was the rigor of development domain, mostly due to unclear description of strengths and limitations of the body of evidence and the procedure for updating the guidelines.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guidelines update – I – Plan and definitions

Since the World Allergy Organization (WAO) Diagnosis and Rationale against Cow's Milk Allergy (DRACMA) Guidelines were published 10 years ago, new evidence has accumulated about the diagnosis, therapy, and specific immunotherapy for cow's milk allergy (CMA). For this reason, WAO has felt the need to update the guidelines.

We introduce here this update. The new DRACMA guidelines aim to comprehensively address the guidance on diagnosis and therapy of both IgE non-IgE-mediated forms of cow's milk allergy in children and adults. They will be divided into 18 chapters, each of which will be dedicated to an aspect. The focus will be on the meta-analyzes and recommendations that will be expressed for the 3 most relevant clinical aspects: (a) the diagnostic identification of the condition; (b) the choice of the replacement formula in case of CMA in infancy when the mother is not able to breastfeed, and (c) the use of specific immunotherapy for cow's milk protein allergy.

Effects of Cow's Milk Components, Goat's Milk and Sheep's Milk Sensitivities on Clinical Findings, and Tolerance Development in Cow's Milk Allergy

Objective:

Cow’s milk (CM) contains some proteins capable of causing an allergic reaction in a sensitized individual and one of the most common causes of food allergy in childhood. Most of the patients will develop tolerance by the age of 3. In this study, we aimed to evaluate sensitivity to CM allergen components as well as goat’s milk (GM) and sheep’s milk cross reactions in cow’s milk allergic (CMA) patients and to figure out the risk factors for tolerance non-development.

Methods:

This is a retrospective cross-sectional study including 66 patients for IgE-mediated CMA with mean age of 38 months. We evaluated the patients in two groups: Group 1 (n=50): Patients who have no tolerance in oral food challenge test; Group 2 (n= 16): Patients who were found tolerant to CM after elimination diet. Cow’s milk-spesific IgE(sIgE), α-lactalbumin(ALA)-sIgE, β-Lactoglobulin(BLG)-sIgE, casein-sIgE, goat’s milk-sIgE, sheep’s milk-sIgE, skin prick tests(SPTs) with CM and GM, eosinophils in peripheral blood were all compared between two groups.

Results:

In the whole group, goat’s milk-sIgE and sheep’s milk-sIgE were positive in 84.8% and ALA-sIgE, BLG-sIgE, casein-sIgE were positive in 69.7%, 62.7%, 77.3% of the patients, respectively. Two groups were similar in terms of age at onset and diagnosis, gender, median elimination period, total IgE levels, cow’s milk-sIgE and eosinophilia (p>0.05). Mean wheal diameters of CM and GM in SPT (p<0.001), goat’s milk-sIgE (p=0.03), sheep’s milk-sIgE (p=0.01) were significantly higher in Group 1. Cow’s milk-sIgE showed a positive correlation with total IgE (p=0.001), eosinophilia percentage (p=0.04), CM wheal diameter in SPT (p=0.001), casein-sIgE (p<0.001), goat’s milk-sIgE (p<0.001), sheep’s milk-sIgE (p<0.001) in Group 1. Patients with respiratory symptoms and history of anaphylaxis had higher cow’s milk-SPT, cow’s milk-sIgE, casein-sIgE, goat’s milk-sIgE, sheep’s milk-sIgE levels(p<0.05). Gastrointestinal and skin symptoms showed no relation with laboratory findings. Any patient with a history of anaphylaxis did not develop tolerance.

Conclusions:

As with cow’s milk-sIgE levels and high induration diameters in SPT; high casein-sIgE, sheep’s milk-sIgE and goat’s milk-sIgE levels are also risk factors for persistence of CMA. Anaphylaxis, as a first reaction, may also be a risk factor. High cow’s milk-sIgE, casein-sIgE, sheep’s milk-sIgE, goat’s milk-sIgE levels are associated with respiratory symptoms.

Reducing the Allergenicity of α-Lactalbumin after Lipid Peroxidation

This study analyzed the effect of lipid peroxidation using 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) and acrolein on the in vitro and in vivo allergenicity of α-lactalbumin (α-La). The structure of oxidized α-La was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, fluorescence spectroscopy, and circular dichroism, whereas the changes in the allergenic properties were evaluated. Lipid peroxidation induced changes to the structural properties that might destroy and/or mask α-La epitopes. In comparison to native α-La, oxidation complexes caused a decrease in the immunoglobulin E (IgE) binding capacity, as observed via immunoblotting. Moreover, the capacity to release mediators and cytokines from KU812 cells was also greatly reduced. In vivo, oxidation with AAPH and acrolein caused a significant reduction in IgE, IgG, IgG1, mast cell protease 1, and plasma histamine, along with the reduction of mast surface c-Kit⁺ and FcεRI⁺ expression. Therefore, these results indicate that oxidation via AAPH and acrolein can potentially reduce the allergenicity of α-La, which can help with the better understanding of the changes in allergenicity of milk allergen by lipid peroxidation.

Enhanced Uptake of Processed Bovine β-Lactoglobulin by Antigen Presenting Cells: Identification of Receptors and Implications for Allergenicity

SCOPE

β-lactoglobulin (BLG) is a major cow milk allergen encountered by the immune system of infants fed with milk-based formulas. To determine the effect of processing on immunogenicity of BLG, this article characterized how heated and glycated BLG are recognized and internalized by APCs. Also, the effect of heat-induced structural changes as well as gastrointestinal digestion on immunogenicity of BLG is evaluated.

METHODS AND RESULTS

The binding and uptake of BLG from raw cow milk and heated either alone (BLG-H) or with lactose/glucose (BLG-Lac and BLG-Glu) to the receptors present on APCs are analyzed by ELISA and cell-binding assays. Heated and glycated BLG is internalized via galectin-3 (Gal-3)and scavenger receptors (CD36 and SR-AI) while binding to the receptor for advanced glycation end products (R AGE) does not cause internalization. Receptor affinity of BLG is dependent on increased hydrophobicity, β-sheet exposure and aggregation. Digested glycated BLG maintained binding to sRAGE and Gal-3 but not to CD36 and SR-AI, and is detected on the surface of APCs. This suggests a mechanism via which digested glycated BLG may trigger innate (via RAGE) and adaptive immunity (via Gal-3).

CONCLUSIONS

This study defines structural characteristics of heated and glycated BLG determining its interaction with APCs via specific receptors thus revealing enhanced immunogenicity of glycated versus heated BLG.

Predictors of a positive oral food challenge to cow's milk in children sensitized to cow's milk

INTRODUCTION AND OBJECTIVES

The diagnosis of IgE-mediated cow's milk allergy (CMA) is often based on clinical history and on specific IgE levels and/or skin-prick tests (SPT), both of which are sensitive but not specific. The gold standard, oral food challenge (OFC), is expensive and time-consuming and involves a risk of severe allergic reactions. This study aimed to determine the value of specific IgEs, ratios of specific IgEs for cow's milk and its components to total IgE, and wheal size on SPT for predicting a positive OFC for CMA.

MATERIAL AND METHODS

We retrospectively studied 72 patients [median age, four years; age range 0.75-15 years] sensitized to cow's milk who underwent OFCs to milk. predictive variables between patients with positive and negative OFCs were compared. Receiver operator characteristic (ROC) curves were uses to assess variables' discriminatory capacity and Youden's index to determine the best cut-offs for predicting CMA.

RESULTS

The OFC was positive in 39 (54%) patients. Wheal size on SPT and all specific IgEs and specific-to-total IgE ratios were significantly different between patients with positive OFCs and those with negative OFCs (p<0.001). The variable with the greatest area under the ROC curve was casein-specific IgE (0.98), followed by β-lactoglobulin-specific IgE (0.923), casein-specific-to-total-IgE ratio (0.919), and α-lactalbumin-specific IgE (0.908). Casein-specific IgE ≥0.95kU/L yielded 88.9% sensitivity and 90.9% specificity.

CONCLUSIONS

In our center, casein-specific IgE >0.95kU/L can obviate an OFC to cow's milk for the diagnosis of CMA in patients sensitized to cow's milk with a compatible history.

A Latin American and Spanish pediatric gastroenterology group's understanding of cow's milk protein allergy diagnosis and treatment: Results of a survey by the Food Allergy Working Group of the Sociedad Latinoamericana de Gastroenterología, Hepatología y Nutrición Pediátrica

INTRODUCTION

There are discrepancies in the diagnosis and management of cow's milk protein allergy (CMPA) in Spain and Latin America. The aim of the present study was to find out how Spanish and Latin American pediatric gastroenterologists diagnose and treat CMPA.

MATERIAL AND METHODS

Pediatric gastroenterologists, members of the Sociedad Latinoamericana de Gastroenterología, Hepatología y Nutrición, were invited to fill out a structured survey, the results of which were then compared with the 2012 and 2014 diagnosis and treatment guidelines, respectively.

RESULTS

The survey results showed that 17% of the participants follow the diagnostic recommendations based on the published consensus and guidelines. To diagnose non-IgE-mediated CMPA, 15% of the participants utilize IgE-specific skin prick tests, 22% use IgE-specific blood tests, and 45% employ oral food challenges. To diagnose IgE-mediated CMPA the percentages for the same diagnostic methods were 57, 83 and 22%, respectively. Once diagnosis is confirmed, 98% of the participants provide dietary recommendations. In children that are not breastfed, 89% of the participants prescribe an initial extensively hydrolyzed formula, 9% an amino acid formula, 1% a soy formula, and 1% a hydrolyzed rice formula. In patients with IgE-mediated CMPA, 34% of the participants carry out an oral challenge once treatment is completed, 39% according to symptom severity, and 27% in relation to IgE-specific testing.

CONCLUSION

CMPA management is diverse and there is poor adherence to the clinical practice guidelines.

Binding of CML-Modified as Well as Heat-Glycated β-lactoglobulin to Receptors for AGEs Is Determined by Charge and Hydrophobicity

Intake of dietary advanced glycation end products (AGEs) is associated with inflammation-related health problems. Nε-carboxymethyl lysine (CML) is one of the best characterised AGEs in processed food. AGEs have been described as ligands for receptors present on antigen presenting cells. However, changes in protein secondary and tertiary structure also induce binding to AGE receptors. We aimed to discriminate the role of different protein modifications in binding to AGE receptors. Therefore, β-lactoglobulin was chemically modified with glyoxylic acid to produce CML and compared to β-lactoglobulin glycated with lactose. Secondary structure was monitored with circular dichroism, while hydrophobicity and formation of β-sheet structures was measured with ANS-assay and ThT-assay, respectively. Aggregation was monitored using native-PAGE. Binding to sRAGE, CD36, and galectin-3 was measured using inhibition ELISA. Even though no changes in secondary structure were observed in all tested samples, binding to AGE receptors increased with CML concentration of CML-modified β-lactoglobulin. The negative charge of CML was a crucial determinant for the binding of protein bound CML, while binding of glycated BLG was determined by increasing hydrophobicity. This shows that sRAGE, galectin-3, and CD36 bind to protein bound CML and points out the role of negatively charged AGEs in binding to AGE receptors.

Component-Resolved Diagnosis in Food Allergies

Component-resolved diagnostics (CRD) in food allergies is an approach utilized to characterize the molecular components of each allergen involved in a specific IgE (sIgE)-mediated response. In the clinical practice, CRD can improve diagnostic accuracy and assist the physician in many aspects of the allergy work-up. CRD allows for discriminatory co-sensitization versus cross-sensitization phenomena and can be useful to stratify the clinical risk associated with a specific sensitization pattern, in addition to the oral food challenge (OFC). Despite this, there are still some unmet needs, such as the risk of over-prescribing unnecessary elimination diets and adrenaline auto-injectors. Moreover, up until now, none of the identified sIgE cutoff have shown a specificity and sensitivity profile as accurate as the OFC, which is the gold standard in diagnosing food allergies. In light of this, the aim of this review is to summarize the most relevant concepts in the field of CRD in food allergy and to provide a practical approach useful in clinical practice.

Cow's Milk Substitutes for Children: Nutritional Aspects of Milk from Different Mammalian Species, Special Formula and Plant-Based Beverages

Cow’s milk and dairy are commonly consumed foods in the human diet and contribute to maintaining a healthy nutritional state, providing unique sources of energy, calcium, protein, and vitamins, especially during early childhood. Milk formula is usually made from cow’s milk and represents the first food introduced into an infant’s diet when breastfeeding is either not possible or insufficient to cover nutritional needs. Very recently, increased awareness of cow’s milk protein allergy and intolerance, and higher preference to vegan dietary habits have influenced parents towards frequently choosing cows’ milk substitutes for children, comprising other mammalian milk types and plant-based milk beverages. However, many of these milk alternatives do not necessarily address the nutritional requirements of infants and children. There is a strong need to promote awareness about qualitative and quantitative nutritional compositions of different milk formulas, in order to guide parents and medical providers selecting the best option for children. In this article, we sought to review the different compositions in terms of macronutrients and micronutrients of milk from different mammalian species, including special milk formulas indicated for cow’s milk allergy, and of plant-based milk alternatives.

A quercetin-based flavanoid (rutin) reverses amyloid fibrillation in β-lactoglobulin at pH 2.0 and 358 K

β-lactoglobulin (BLG) is a well characterized milk protein and a model for folding and aggregation studies. Rutin is a quercetin based-flavanoid and a famous dietary supplement. It is a potential protector from coronary heart disease, cancers, and inflammatory bowel disease. In this study, amyloid fibrillation is reported in BLG at pH 2.0 and temperature 358 K. It is inhibited to some extent by rutin with a rate of 99.3 h^-1 M^-1. Amyloid fibrillation started taking place after 10 h of incubation and completed near 40 h at a rate of 16.6 × 10^-3 h^-1, with a plateau during 40-108 h. Disruption of tertiary structure of BLG and increased solvent accessibility of hydrophobic core seem to trigger intermolecular assembly. Increase in 7% β-sheet structure at the cost of 10% α-helical structures and the electron micrograph of BLG fibrils at 108 h further support the formation of amyloid. Although it could not block amyloidosis completely, and even the time required to reach plateau remains the same, a decrease of growth rate from 16.6 × 10^-3 to 13.5 × 10^-3 h^-1 was observed in the presence of 30.0 μM rutin. Rutin seems to block solvent accessibility of the hydrophobic core of BLG. A decrease in the fibril population was observed in electron micrographs, with the increase in rutin concentration. All evidences indicate reversal of fibrillation in BLG in the presence of rutin.

[Non-IgE-mediated cow's milk allergy: Consensus document of the Spanish Society of Paediatric Gastroenterology, Hepatology, and Nutrition (SEGHNP), the Spanish Association of Paediatric Primary Care (AEPAP), the Spanish Society of Extra-hospital Paediatrics and Primary Health Care (SEPEAP), and the Spanish Society of Paediatric ClinicaL Immunology, Allergy, and Asthma (SEICAP)]

Non-IgE-mediated cow's milk allergy is a frequent disorder in paediatrics. As patients might be seen by professionals from different specialties and levels of expertise, a great variability in diagnostic procedures and disease monitoring is commonly observed. Therefore, four scientific societies involved in its management have developed a consensus document providing specific recommendations related to its prevention, diagnosis, treatment and follow up.

Current Trends in Tolerance Induction in Cow's Milk Allergy: From Passive to Proactive Strategies

This review addresses the current strategies of inducing tolerance development in infant and childhood cow's milk protein allergy (CMPA). The change in prevention strategies for CMPA has been emphasized based on the lack of evidence to support the efficacy of food allergen avoidance in infancy and the concept of the dual-allergen-exposure hypothesis, which suggests that allergen exposure through the skin leads to sensitization, whereas early oral consumption of allergenic food protein induces oral tolerance. The new approach is based on the likelihood of early introduction of allergenic foods to the infant's diet to reduce the development of food allergies through oral tolerance induction. The latest treatment guidelines recommend the continuation of breast feeding and the elimination of cow's milk and products from the maternal diet in exclusively breast-fed infants with CMPA, the use of an extensively hydrolyzed infant formula (eHF) with proven efficacy in CMPA as the first elimination diet in formula-fed infants with CMPA and the use of amino acid-based formula (AAF) in severe cases, such as anaphylaxis, enteropathy, eosinophilic esophagitis, and food protein-induced enterocolitis syndrome (FPIES), as well as cases of multiple system involvement, multiple food allergies, and intolerance to extensively hydrolyzed formula (eHF). In conclusion, this paper presents the current knowledge on tolerance development in infants and children with CMPA to increase the awareness of the clinicians concerning the new approaches in CMPA treatment Tolerance development is considered a relatively new concept in CMPA, inducing a shift in interventions in CMPA from a passive (avoidance of responsible allergen) toward a proactive (tolerance induction) strategy.

Interleukin-6 and Tumor Growth Factor-β are Risk Factors for Idiopathic Epistaxis

Objective

To evaluate the serum levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, tumor growth factor (TGF)-β, endothelin, and immunoglobulin (Ig)E in patients with idiopathic epistaxis, compared with healthy control individuals.

Methods

Serum levels of IL-6, IL-8, TNF-α, TGF-β, endothelin, and IgE were evaluated in 110 patients with idiopathic epistaxis and 100 healthy controls using the enzyme-linked immunosorbent assay (ELISA) technique.

Results

Serum levels of IL-6 (P <.001) and TGF-β (P = .001) were significantly increased in patients with idiopathic epistaxis, compared with controls. TNF-α serum levels were significantly increased in male patients, compared with female patients (P = .053). We observed decreased antihistamine levels and increased expression of TGF-β (P = .02) and TNF-α (P = .02), respectively.

Conclusions

IL-6 and TGF-β appear to participate in the pathogenesis of idiopathic epistaxis. TNF-α may be considered a risk factor for male patients in developing epistaxis. Antihistamines may inhibit angiogenesis by decreasing expression of TGF-β and increasing expression of TNF-α.

The role of regulatory T cells in the acquisition of tolerance to food allergens in children

Food allergy is a pathological immune reaction that identifies certain harmless food proteins, usually tolerated by the majority of the people, as a threat. The prevalence of these food allergies is increasing worldwide and currently affects 8% of children. Exacerbated reactions to milk, egg and peanut are the most frequent in the pediatric population. It is well known that allergic diseases are a type 2 T-helper (Th2) immune response, characterized by the elevated production of IgE antibodies. However, little is known about the immune mechanisms responsible for the development of clinical tolerance toward food allergens. Recent studies have suggested the key role of regulatory T cells (Tregs) in controlling allergic inflammation. In this review, we discuss the importance of Tregs in the pathogenesis of food allergy and the acquisition of oral tolerance in children. Further investigation in this area will be crucial for the identification of predictive markers and the development of new therapies, which will represent a clinical and social benefit for these allergic diseases.

Iberian consensus on cow's milk allergy: The CIBAL Study

BACKGROUND

The present study explores the professional opinion of a wide range of experts from the Iberian Peninsula (Spain and Portugal) and their degree of consensus about CMPA's prevention, diagnosis, treatment and progression.

MATERIAL AND METHODS

A 57-item survey divided in four blocks: Prevention (14 items), Diagnosis (10 items), Treatment (19 items) and Progression (14 items) was completed by 160 panellists, experts in CPMA management (116 Spain, 44 Portugal). Each one answered the questionnaire, formulated in Portuguese and Spanish, by individually accessing an online platform in two consecutive rounds. Five possible answers were possible: "completely agree", "agree", "neither agree nor disagree", "disagree" and "completely disagree". A modified Delphi method was used.

RESULTS

Consensus (more than 66% agree) was reached in 39 items (68.4%) and Discrepancy (less than 50% agree) in nine items (15.7%). Block separated analysis offers valuable differences regarding consensus. The Prevention block only reached 50%; the Diagnosis block 90%; the Treatment block 73.68%, showing a high degree of agreement on dietary treatment (15/16 items), and discrepancy or less agreement on immunotherapy treatments. The Progression block reached 71.4% consensus with discrepancy with regard to the time to perform oral food challenge and negatives prognosis consequences of accidental milk ingestion.

CONCLUSIONS

This study displays the current opinions of a wide group of experts on CMPA from the Iberian Peninsula and evidence discussion lines in CMPA management. The questions on which there were situations of discrepancy, provide us with very useful information for promoting new, rigorous research enabling us to draw conclusions on these controversial aspects.

The effect of baked milk on accelerating unheated cow's milk tolerance: A control randomized clinical trial

BACKGROUND

Assessing the effect of adding baked milk products to the diet of patients with cow's milk allergy on accelerating the formation of tolerance.

METHOD

A randomized clinical trial was carried out with 84 patients (6 months-3 years old) diagnosed with allergy to cow's milk who tolerated baked milk in form of muffin in oral food challenge (OFC). The subjects were divided randomly into case and control groups matched for age and sex. Patients in the case group were asked to consume baked milk in the form of muffin for 6 months and then to consume baked cheese in the form of pizza for another 6 months. The control group were instructed to strictly avoid any milk products for 1 year. Skin prick test (SPT) and serum-specific immunoglobulin E (sIgE) levels (ImmunoCAP) of milk, casein, and beta-lactoglobulin were measured before and after the study. In addition, those in the case group who had satisfactorily tolerated baked products during the study as well as all the subjects in the control group underwent an OFC to evaluate unheated milk tolerance at the end of the study.

RESULTS

It was shown that by the end of the 1-year study period, 88.1% (37/42) of the patients in the case group and 66.7% (28/42) of those in control group had developed tolerance to unheated milk (P-value: 0.018). The results of milk-specific SPT and sIgE levels showed a significant decrease in the case group. Initial sIgE levels could not predict unheated milk tolerance in case and control groups.

CONCLUSION

Introducing baked milk products into the diet of patients with milk allergy can accelerate the tolerance of unheated milk in these patients. sIgE levels of milk, casein, and beta-lactoglobulin did not predict the tolerance of unheated milk.