Prevalence and risk factors for milk allergy overdiagnosis in the BEEP trial cohort.

BACKGROUND: Cow's milk allergy (CMA) overdiagnosis in young children appears to be increasing and has not been well characterised. We used a clinical trial population to characterise CMA overdiagnosis and identify individual-level and primary care practice-level risk factors. METHODS: We analysed data from 1394 children born in England in 2014-2016 (BEEP trial, ISRCTN21528841). Participants underwent formal CMA diagnosis at ≤2 years. CMA overdiagnosis was defined in three separate ways: parent-reported milk reaction; primary care record of milk hypersensitivity symptoms; and primary care record of low-allergy formula prescription. RESULTS: CMA was formally diagnosed in 19 (1.4%) participants. CMA overdiagnosis was common: 16.1% had parent-reported cow's milk hypersensitivity, 11.3% primary care recorded milk hypersensitivity and 8.7% had low-allergy formula prescription. Symptoms attributed to cow's milk hypersensitivity in participants without CMA were commonly gastrointestinal and reported from a median age of 49 days. Low-allergy formula prescriptions in participants without CMA lasted a median of 10 months (interquartile range 1, 16); the estimated volume consumed was a median of 272 litres (26, 448). Risk factors for CMA overdiagnosis were high practice-based low-allergy formula prescribing in the previous year and maternal report of antibiotic prescription during pregnancy. Exclusive formula feeding from birth was associated with increased low-allergy formula prescription. There was no evidence that practice prescribing of paediatric adrenaline auto-injectors or anti-reflux medications, or maternal features such as anxiety, age, parity and socioeconomic status were associated with CMA overdiagnosis. CONCLUSION: CMA overdiagnosis is common in early infancy. Risk factors include high primary care practice-based low-allergy formula prescribing and maternal report of antibiotic prescription during pregnancy.

Integrated gut metabolome and microbiome fingerprinting reveals that dysbiosis precedes allergic inflammation in IgE-mediated pediatric cow's milk allergy.

BACKGROUND: IgE-mediated cow's milk allergy (IgE-CMA) is one of the first allergies to arise in early childhood and may result from exposure to various milk allergens, of which ß-lactoglobulin (BLG) and casein are the most important. Understanding the underlying mechanisms behind IgE-CMA is imperative for the discovery of novel biomarkers and the design of innovative treatment and prevention strategies. METHODS: We report a longitudinal in vivo murine model, in which two mice strains (BALB/c and C57Bl/6) were sensitized to BLG using either cholera toxin or an oil emulsion (n = 6 per group). After sensitization, mice were challenged orally, their clinical signs monitored, antibody (IgE and IgG1) and cytokine levels (IL-4 and IFN-γ) measured, and fecal samples subjected to metabolomics. The results of the murine models were further extrapolated to fecal microbiome-metabolome data from our population of IgE-CMA (n = 22) and healthy (n = 23) children (Trial: NCT04249973), on which polar metabolomics, lipidomics and 16S rRNA metasequencing were performed. In vitro gastrointestinal digestions and multi-omics corroborated the microbial origin of proposed metabolic changes. RESULTS: During mice sensitization, we observed multiple microbially derived metabolic alterations, most importantly bile acid, energy and tryptophan metabolites, that preceded allergic inflammation. We confirmed microbial dysbiosis, and its associated effect on metabolic alterations in our patient cohort, through in vitro digestions and multi-omics, which was accompanied by metabolic signatures of low-grade inflammation. CONCLUSION: Our results indicate that gut dysbiosis precedes allergic inflammation and nurtures a chronic low-grade inflammation in children on elimination diets, opening important new opportunities for future prevention and treatment strategies.

Allergen-specific B cell responses in oral immunotherapy-induced desensitization, remission, and natural outgrowth in cow's milk allergy.

BACKGROUND: Antigen-specific memory B cells play a key role in the induction of desensitization and remission to food allergens in oral immunotherapy and in the development of natural tolerance (NT). Here, we characterized milk allergen Bos d 9-specific B cells in oral allergen-specific immunotherapy (OIT) and in children spontaneously outgrowing cow's milk allergy (CMA) due to NT. METHODS: Samples from children with CMA who received oral OIT (before, during, and after), children who naturally outgrew CMA (NT), and healthy individuals were received from Stanford biobank. Bos d 9-specific B cells were isolated by flow cytometry and RNA-sequencing was performed. Protein profile of Bos d 9-specific B cells was analyzed by proximity extension assay. RESULTS: Increased frequencies of circulating milk allergen Bos d 9-specific B cells were observed after OIT and NT. Milk-desensitized subjects showed the partial acquisition of phenotypic features of remission, suggesting that desensitization is an earlier stage of remission. Within these most significantly expressed genes, IL10RA and TGFB3 were highly expressed in desensitized OIT patients. In both the remission and desensitized groups, B cell activation-, Breg cells-, BCR-signaling-, and differentiation-related genes were upregulated. In NT, pathways associated with innate immunity characteristics, development of marginal zone B cells, and a more established suppressor function of B cells prevail that may play a role in long-term tolerance. The analyses of immunoglobulin heavy chain genes in specific B cells demonstrated that IgG2 in desensitization, IgG1, IgA1, IgA2, IgG4, and IgD in remission, and IgD in NT were predominating. Secreted proteins from allergen-specific B cells revealed higher levels of regulatory cytokines, IL-10, and TGF-ß after OIT and NT. CONCLUSION: Allergen-specific B cells are essential elements in regulating food allergy towards remission in OIT-received and naturally resolved individuals.

Longitudinal Growth Trajectories in Children with Cow's Milk Allergy: Effects of Elimination Diet and Post-Termination Period.

INTRODUCTION: The primary dietary approach for managing cow's milk allergy (CMA) is the elimination diet. We aimed to compare the growth patterns of children with CMA during and after the elimination diet with healthy peers and identify influencing factors. METHODS: We compared 74 CMA children with age-matched healthy peers. Anthropometric data were collected during the third month of cow's milk elimination (CME) diet (T1), 3 months after diet cessation (T2), and after ≥3 months of normal diet (T3). Control group measurements coincided. Nutrient intake was assessed by a 3-day record, and patient laboratory results were noted at T3. RESULTS: CMA children had consistently lower weight-for-age (WFA) and height-for-age (HFA) z-scores than controls. WtHt z-score of patients was lower than those of the healthy group at T2. HC z-scores of patients were lower than those of the healthy group at T0, T2, and T3. At T3, the HFA z-score of the CME group demonstrated a negative correlation with the duration of the elimination diet (p = 0.045). Inadequate intake of energy, vitamins A, E, B1, B6, C, folic acid, magnesium, and iron was significantly higher in CMA children (p < 0.05). T3 WFA z-score correlated positively with fiber, vitamin B1, magnesium, and iron intake (p < 0.05). T3 WtHt showed a positive moderate correlation with energy, protein, vitamin E, vitamin B1, vitamin B2, vitamin B6, calcium, magnesium, phosphor, iron intake (p < 0.05). CONCLUSIONS: Post-elimination diet, children with CMA need sustained monitoring and potentially micronutrient supplementation to match healthy peers' growth.

The contribution of milk substitutes to the nutritional status of children with cow's milk allergy.

BACKGROUND: The impact of alternative milk substitutes on the nutritional status of children with cow's milk allergy (CMA), the prevailing cause of food allergies, is unresolved. METHODS: A cross-sectional study was performed in children older than 2 years with IgE-mediated CMA. Patients' clinical characteristics, anthropometric measurements, dietary intake (by 3-day food diary), and biochemical markers of nutritional status were assessed. RESULTS: One hundred two children with CMA (68.6% boys; median age, 3.7 years; 51% multiple food allergies) were evaluated. 44.1% of the children consumed plant-based beverages (PBB), 19.6% therapeutic formula and 36.3% did not consume any milk substitutes. In all age groups, dietary calcium, riboflavin, and vitamin D intake of those who did not use milk substitutes were lower than those who consumed formula or PBB (p < .01). Also in the 2-3 years old age group, dietary zinc (p = .011) and iron intake (p = .004) of the formula-fed group was higher. Formula-fed patients had higher levels of 25-OH vitamin D (µg/L) and serum vitamin B12 (ng/L) than PBB-fed patients (respectively; p < .001, p = .005) and those who did not consume any milk substitute (p < .001). Patients of all ages who did not utilize a milk substitute failed to obtain an adequate amount of dietary calcium. CONCLUSION: The use of milk substitutes positively affects dietary calcium, riboflavin, and vitamin D intake in CMA, but their contribution is variable. Those who do not use milk substitutes are at greater risk inadequate of dietary calcium intake. Personalized nutritional advice, given the clinical diversity and the impact of individual differences, is required.

A retrospective comparison of IgE-mediated cow's milk protein allergy management strategies in pediatric cohorts.

BACKGROUND: Complete avoidance of milk is the usual management for IgE-mediated cow's milk protein allergy (CMPA). A baked milk ladder is a method of dietary advancement therapy in IgE-mediated CMPA in Ireland, while in Spain, avoidance of milk awaiting natural tolerance acquisition through an oral food challenge (OFC) is employed. The aim of this study was to evaluate the use of dietary advancement therapy using a milk ladder compared with complete avoidance of milk for managing IgE-mediated CMPA. METHODS: This is a retrospective chart review of 371 pediatric patients from the population who have been treated for IgE-mediated CMPA between 2011 and 2020, with the milk ladder (Ireland) or complete avoidance followed by an OFC (Spain). The main outcome was the introduction of cow's milk. RESULTS: Milk ladder patients were 3.67 times more likely to succeed in comparison with milk avoidance (p < .001). Anaphylaxis during the treatment period occurred in 34 patients in the milk avoidance groups, while three patients in the milk ladder group experienced anaphylaxis due to accidental exposure to milk (p < .001). Failure to complete treatment was associated with a higher skin prick test in the milk avoidance group and a raised specific IgE in the milk ladder group. CONCLUSION: This is the first study that compares outcomes of dietary advancement therapy to complete avoidance for CMPA management, demonstrating that cow's milk can be successfully and safely reintroduced using dietary advancement therapy using a milk ladder.

Current insights into cow's milk allergy in children: Microbiome, metabolome, and immune response-A systematic review.

The increasing prevalence of IgE-mediated cow's milk allergy (CMA) in childhood is a worldwide health concern. There is a growing awareness that the gut microbiome (GM) might play an important role in CMA development. Therefore, treatment with probiotics and prebiotics has gained popularity. This systematic review provides an overview of the alterations of the GM, metabolome, and immune response in CMA children and animal models, including post-treatment modifications. MEDLINE, PubMed, Scopus, and Web of Science were searched for studies on GM in CMA-diagnosed children, published before 1 March 2023. A total of 21 articles (13 on children and 8 on animal models) were included. The studies suggest that the GM, characterized by an enrichment of the Clostridia class and reductions in the Lactobacillales order and Bifidobacterium genus, is associated with CMA in early life. Additionally, reduced levels of short-chain fatty acids (SCFAs) and altered amino acid metabolism were reported in CMA children. Commonly used probiotic strains belong to the Bifidobacterium and Lactobacillus genera. However, only Bifidobacterium levels were consistently upregulated after the intervention, while alterations of other bacteria taxa remain inconclusive. These interventions appear to contribute to the restoration of SCFAs and amino acid metabolism balance. Mouse models indicate that these interventions tend to restore the Th 2/Th 1 balance, increase the Treg response, and/or silence the overall pro- and anti-inflammatory cytokine response. Overall, this systematic review highlights the need for multi-omics-related research in CMA children to gain a mechanistic understanding of this disease and to develop effective treatments and preventive strategies.

Development of a low allergenic product for patients with milk allergy and assessment of its specific IgE reactivity.

BACKGROUND: Milk oral immunotherapy is the riskiest and most unpredictable form of oral immunotherapy. We aimed to produce a low allergenic product than conventional once baked-cake/muffin, to develop indirect in-house ELISA to check the tolerance status with milk products and evaluate IgE reactivity of patients' sera via western blotting (WB) and indirect in-house ELISA. METHOD: A low allergenic product named biscotti-twice baked-cake was developed, and the total protein concentration was determined. The protein content was studied by SDS-PAGE and proteomics. Milk-specific IgE (sIgE) binding assays were performed by WB and indirect in-house ELISA by using patients' sera. RESULTS: Casein band intensity was observed to be lower in the biscotti-twice baked-cake than in the once baked-cake (p = .014). Proteomics analysis and αS1-casein measurement showed that the lowest intensity of casein was found in biscotti. The low binding capacity of milk sIgE to biscotti compared with once baked-cake was shown by WB (p = .0012) and by indirect in-house ELISA (p = .0001). In the ROC analysis, the area under the curve (AUC) of the in-house ELISA IgE was comparable with Uni-CAP milk and casein sIgE. The AUC of the in-house ELISA IgE for cake (0.96) and biscotti (1) was slightly better than Uni-CAP milk sIgE (0.94; 0.97) and casein sIgE (0.96; 0.97), respectively. CONCLUSION: The low allergenicity of the newly developed low allergenic product "biscotti-twice baked-cake" has been demonstrated by in vitro experiments. Biscotti could be a safe treatment option than once baked-cake/muffin in patients who are reactive to once baked-milk products.

Diagnosis and management of food allergy-induced constipation in young children-An EAACI position paper.

The recognition of constipation as a possible non-Immunoglobulin E (IgE)-mediated allergic condition is challenging because functional constipation (unrelated to food allergies) is a common health problem with a reported worldwide prevalence rate of up to 32.2% in children. However, many studies in children report challenge proven cow's milk allergy and constipation as a primary symptom and have found that between 28% and 78% of children improve on a cow's milk elimination diet. Due to the paucity of data and a focus on IgE-mediated allergy, not all food allergy guidelines list constipation as a symptom of food allergy. Yet, it is included in all cow's milk allergy guidelines available in English language. The Exploring Non-IgE-Mediated Allergy (ENIGMA) Task Force (TF) of the European Academy for Allergy and Clinical Immunology (EAACI) considers in this paper constipation in the context of failure of standard treatment and discuss the role of food allergens as culprit in constipation in children. This position paper used the Delphi approach in reaching consensus on both diagnosis and management, as currently published data are insufficient to support a systematic review.

Epigenomic and epigenetic investigations of food allergy.

As a potential link between genetic predisposition, environmental exposures, and food allergy outcomes, epigenetics has been a molecular variable of interest in ongoing efforts to understand food allergy mechanisms and outcomes. Here we review population-based investigations of epigenetic loci associated with food allergy, focusing on established clinical food allergy. We first provide an overview of epigenetic mechanisms that have been studied in cohorts with food allergy, predominantly DNA methylation but also microRNA. We then discuss investigations that have implemented epigenome-wide approaches aimed at genome-wide profiling and discovery. Such epigenome-wide studies have collectively identified differentially methylated and differentially regulated loci associated with T cell development, antigen presentation, reaction severity, and causal mediation in food allergy. We then discuss candidate-gene investigations that have honed in on Th1, Th2, T regulatory, and innate genes of a priori interest in food allergy. These studies have highlighted methylation changes in specific candidate genes as associated with T regulatory cell activity as well as differential methylation of Type 1 and Type 2 cytokine genes associated with various food allergies. Intriguingly, epigenetic loci associated with food allergy have also been explored as potential biomarkers for the clinical management of food allergy. We conclude by highlighting several priority directions for advancing population-based epigenomic and epigenetic understandings of food allergy.

The Natural History and Risk Factors for the Development of Food Allergies in Children and Adults.

PURPOSE OF REVIEW: This narrative review explores food allergy prevalence and natural history stratified by life stages, especially in context of evolving knowledge over the last few decades. RECENT FINDINGS: The prevalence of food allergy remains highest in early childhood with common food triggers being cow's milk, soy, hen's egg, wheat, peanut, tree nuts, sesame, fish, and shellfish. This correlates with certain risk factors especially pertinent in the postnatal period which appear to predispose an individual to developing a food allergy. Some allergies (such as milk and egg) were previously thought to be easily outgrown in early life; however, recent studies suggest increasing rates of persistence of these allergies into young adulthood; the reason behind this is unknown. Despite this, there is also evidence demonstrating that food allergies can be outgrown in adolescents and adults. An understanding of the paradigm shifts in the natural history of food allergy allows clinicians to provide updated, age-appropriate, and tailored advice for patients on the management and prognosis of food allergy.

Tolerance development in cow's milk-allergic children receiving amino acid-based formula with synbiotics: 36-Months follow-up of a randomized controlled trial (PRESTO Study).

The objective of the present study is to assess the rates of acquired tolerance to cow's milk (CM) after 36 months in subjects who consumed amino acid-based formula with synbiotics (AAF-S) or amino acid-based formula without synbiotics (AAF) during a 1-year intervention period in early life as part of the PRESTO study (Netherlands Trial Register number NTR3725). Differences in CM tolerance development between groups were analysed using a logistic regression model. Results show that the proportion of subjects (mean [±SD] age, 3.8 ± 0.27 years) who developed CM tolerance after 36 months was similar in the group receiving AAF-S (47/60 [78%]) and in the group receiving AAF (49/66 [74%]) (p = 0.253), that is, figures comparable to natural outgrowth of CM allergy. Our data suggest that the consumption of AAF and absence of exposure to CM peptides do not slow down CM tolerance acquisition.

The evolution of Cow's Milk-related Symptom Score (CoMiSS™) in presumed healthy infants.

The Cow's Milk-related Symptom Score (CoMiSS™) is a scoring system that reflects the appearance and intensity of symptoms possibly related to consumption of cow's milk. The original tool was recently updated by changing the cut-off, and the stool scale and by adding angioedema. There is no data available regarding the natural evolution of CoMiSS in infants with no cow's milk allergy (no-CMA) or a comparison between original and updated CoMiSS values. We determined the original and the updated CoMiSS in infants not diagnosed with cow's milk allergy. The evolution of CoMiSS during the first year of life was assessed repetitively during predefined check-ups at 1.5, 3, 4, 6, 8, 10, and 12 months. The original and updated scores were compared with the Wilcoxon Signed-Rank Test. We also tested the impact of feeding type, age, gender, and order in the family on the CoMiSS. One hundred and twenty-two infants were included. CoMiSS values during the first year of life showed an inverse relation to age. The difference in CoMiSS between the original and updated versions was significant at 6,8,10, and 12 months (p < 0.001), related to the switch from the Bristol Stool Form Scale to the Brussels Infants and Toddlers Stool Scale (BITSS). The difference between both versions of CoMiSS was not significantly different in infants < 6 months (p = 0.999 at 1.5 and 4 months, and p = 0.586 at 3 months, respectively).Conclusion: CoMiSS decreases with age during the first year of life. While there is no difference between the two CoMiSS versions in healthy infants under 6 months of age, the CoMiSS value in the updated version is lower than the original 1 in infants aged 6 to 12 months. What is known? • The Cow's Milk-related Symptom Score (CoMiSS) is a validated awareness tool for cow's milk allergy (CMA). • A CoMiSS of ≥ 10 indicates a risk for cow's milk allergy. What is new? • The natural evolution of CoMiSS in infants not diagnosed with CMA (no-CMA) shows an inverse relation to age. • There is no difference between the original and the updated CoMiSS versions in no-CMA-infants under six months of age, but the updated CoMiSS is lower in infants 6-12 months than the original one.

Micronutrients in infants suffering from cow's milk allergy fed with dietary formulas and breast milk.

INTRODUCTION: Cow's milk allergy (CMA) is the most common food allergy in infants. As this food allergy indicates a wide range of clinical syndromes due to immunological reactions to cow's milk proteins, we aimed to evaluate the status of micronutrients in infants suffering from cow's milk allergy. METHODS: In this historical cohort study, infants with CMA were divided into two equal groups: breastfeeding and diet formula feeding. Data were gathered by a form, including the micronutrients such as iron, selenium, calcium, phosphorus, zinc, and vitamin D. Groups were compared and data were analyzed by the IBM SPSS version 21. RESULTS: This study involved 60 six-month-old infants, and the findings revealed no significant difference between the two groups concerning magnesium, phosphorus, zinc, and vitamin D. However, infants in the formula-feeding group exhibited significantly elevated mean serum levels of iron and selenium, whereas breastfed infants displayed higher levels of calcium. CONCLUSION: The findings of this research revealed a significant difference in calcium, selenium, and iron levels between formula-fed and breastfed infants, even though all variables were within the normal range for both groups. In light of these results, conducting further studies with a larger sample size and extended follow-up periods becomes imperative.

Targeting Food Allergy with Probiotics.

The globally dramatic increase in food allergy prevalence and severity is demanding effective preventive and therapeutic strategies. Food allergy derives from a defect of immune tolerance mechanisms. Immune tolerance is modulated by gut microbiome composition and function, and gut microbiome dysbiosis has been associated with the development of food allergy. Selected probiotic strains could regulate immune tolerance mechanisms. The mechanisms are multiple and are still not completely defined. Increasing evidence is providing useful information on the choice of optimal bacterial species/strains, dosage, and timing for intervention. The increased knowledge on the crucial role played by postbiotic gut microbiome-derived metabolites, such as butyrate, is also opening the way to a post- biotic approach in the stimulation of immune tolerance.

Effect of lactic acid bacteria fermentation on cow milk allergenicity and antigenicity: A review.

Cow milk is a major allergenic food. The potential prevention and treatment effects of lactic acid bacteria (LAB)-fermented dairy products on allergic symptoms have garnered considerable attention. Cow milk allergy (CMA) is mainly attributed to extracellular and/or cell envelope proteolytic enzymes with hydrolysis specificity. Numerous studies have demonstrated that LAB prevents the risk of allergies by modulating the development and regulation of the host immune system. Specifically, LAB and its effectors can enhance intestinal barrier function and affect immune cells by interfering with humoral and cellular immunity. Fermentation hydrolysis of allergenic epitopes is considered the main mechanism of reducing CMA. This article reviews the linear epitopes of allergens in cow milk and the effect of LAB on these allergens and provides insight into the means of predicting allergenic epitopes by conventional laboratory analysis methods combined with molecular simulation. Although LAB can reduce CMA in several ways, the mechanism of action remains partially clarified. Therefore, this review additionally attempts to summarize the main mechanism of LAB fermentation to provide guidance for establishing an effective preventive and treatment method for CMA and serve as a reference for the screening, research, and application of LAB-based intervention.

Gut microbiota and fecal metabolites in sustained unresponsiveness by oral immunotherapy in school-age children with cow's milk allergy.

BACKGROUND: Oral immunotherapy (OIT) can ameliorate cow's milk allergy (CMA); however, the achievement of sustained unresponsiveness (SU) is challenging. Regarding the pathogenesis of CMA, recent studies have shown the importance of gut microbiota (Mb) and fecal water-soluble metabolites (WSMs), which prompted us to determine the change in clinical and gut environmental factors important for acquiring SU after OIT for CMA. METHODS: We conducted an ancillary cohort study of a multicenter randomized, parallel-group, delayed-start design study on 32 school-age children with IgE-mediated CMA who underwent OIT for 13 months. We defined SU as the ability to consume cow's milk exceeding the target dose in a double-blind placebo-controlled food challenge after OIT followed by a 2-week-avoidance. We longitudinally collected 175 fecal specimens and clustered the microbiome and metabolome data into 29 Mb- and 12 WSM-modules. RESULTS: During OIT, immunological factors improved in all participants. However, of the 32 participants, 4 withdrew because of adverse events, and only 7 were judged SU. Gut environmental factors shifted during OIT, but only in the beginning, and returned to the baseline at the end. Of these factors, milk- and casein-specific IgE and the Bifidobacterium-dominant module were associated with SU (milk- and casein-specific IgE; OR for 10 kUA/L increments, 0.67 and 0.66; 95%CI, 0.41-0.93 and 0.42-0.90; Bifidobacterium-dominant module; OR for 0.01 increments, 1.40; 95%CI, 1.10-2.03), and these associations were observed until the end of OIT. CONCLUSIONS: In this study, we identified the clinical and gut environmental factors associated with SU acquisition in CM-OIT.

Natural history of cow's milk allergy in children aged 6-12 years.

BACKGROUND: Approximately 50%-90% of children with immediate-type cow's milk allergy (CMA) acquire tolerance by pre-school age. We aimed to investigate the acquisition rate of CMA tolerance in children aged 6-12 years. METHODS: We included children with CMA who persisted until the age of 6. Tolerance was defined as passing an oral food challenge with 200 mL of unheated cow's milk (CM) or consuming 200 mL of CM without symptoms, whereas persistent CMA was defined as fulfilling neither of these criteria by 12 years old. Children receiving oral immunotherapy (OIT) were excluded from the primary analysis. Risk factors associated with persistent CMA were assessed using Cox regression analysis. RESULTS: Of 80 included children, 30 (38%) had previous CM anaphylaxis, and 40 (50%) had eliminated CM completely from their diet. The median CM-specific immunoglobulin E (sIgE) level at 6 years old was 12.0 kUA /L. Tolerance was acquired by 25 (31%) and 46 (58%) children by the age of 9 and 12 years, respectively. At baseline, persistent CMA was associated with higher CM-sIgE levels (hazard ratio 2.29, 95% confidence interval 1.41-3.73, optimal cutoff level 12.7 kUA /L), previous CM anaphylaxis (2.07, 1.06-4.02), and complete CM elimination (3.12, 1.46-6.67). No children with CMA who had all three risk factors (n = 14) acquired tolerance. CONCLUSION: Except for OIT patients, more than half of children with CMA at 6 years old acquired tolerance by 12 years old. Children with CMA who have the risk factors are less likely to acquire tolerance.

Consumption of cow's milk formula in the nursery and the development of milk allergy.

BACKGROUND: The effect of the amount of transient cow's milk formula (CMF) consumed during the first days of life on IgE-cow's milk allergy (IgE-CMA) is unknown. METHODS: A cohort of 58 patients with IgE-CMA was identified from a large scale population-based study of 13,019 infants followed from birth. A group of 116 infants matched for sex and breastfeeding only duration (beyond the nursery period), and another random group of 259 healthy infants were used as controls. Parents were interviewed and the infants' medical records were searched to assess CMF consumption in the nursery. RESULTS: While 96% of the mothers of the 174 infants (58 with Cow's milk allergy and 116 controls) reported on exclusive breastfeeding during the stay in the nursery, CMF consumption was documented in 96 (55%) of the infants. Of those, most (57; 59%) received one to three feedings, 20 (21%) received four to nine feedings, and 19 (20%) received ≥10 feedings. Fewer formula feeds (1-3) were significantly more common in the allergic group than ≥4 feeds (p = 0.0003) and no feeds at all (p = 0.02) compared to controls (n = 116). Of those exclusively breastfed in the nursery, 13/23 allergic infants (57%) introduced CMF at age 105-194 days (the period with highest-risk for IgE-CMA) compared to 33/98 (34%) from the random control group (n = 259) (p = 0.04). CONCLUSIONS: Most infants end up receiving few CMF feeds in the nursery. Transient CMF in the nursery is associated with increased risk of IgE-CMA.