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This review provides general information to serve as a primer for those embarking on understanding food allergy and also details advances and updates in epidemiology, pathogenesis, diagnosis, and treatment that have occurred over the 4 years since our last comprehensive review. Although firm prevalence data are lacking, there is a strong impression that food allergy has increased, and rates as high as approximately 10% have been documented. Genetic, epigenetic, and environmental risk factors are being elucidated increasingly, creating potential for improved prevention and treatment strategies targeted to those at risk. Insights on pathophysiology reveal a complex interplay of the epithelial barrier, mucosal and systemic immune response, route of exposure, and microbiome among other influences resulting in allergy or tolerance. The diagnosis of food allergy is largely reliant on medical history, tests for sensitization, and oral food challenges, but emerging use of component-resolved diagnostics is improving diagnostic accuracy. Additional novel diagnostics, such as basophil activation tests, determination of epitope binding, DNA methylation signatures, and bioinformatics approaches, will further change the landscape. A number of prevention strategies are under investigation, but early introduction of peanut has been advised as a public health measure based on existing data. Management remains largely based on allergen avoidance, but a panoply of promising treatment strategies are in phase 2 and 3 studies, providing immense hope that better treatment will be imminently and widely available, whereas numerous additional promising treatments are in the preclinical and clinical pipeline.

FPIES affects estimated 0.5% of US children and 0.2% of adults (approximately 900,000 people). These data suggest that comprehensive epidemiologic studies are needed to better characterize the public health burden of FPIES.

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated gastrointestinal allergic disorder. Large population-based FPIES studies are lacking.We sought to determine the incidence and clinical characteristics of FPIES in Australian infants.An Australia-wide survey (2012-2014) was undertaken through the Australian Paediatric Surveillance Unit, with monthly notification of new cases of acute FPIES in infants aged less than 24 months by 1400 participating pediatricians.Two hundred thirty infants with FPIES were identified. The incidence of FPIES in Australian infants (24 months) was 15.4/100,000/y. Median age of first episode, diagnosis, and notification were 5, 7, and 10 months, respectively. There was no sex predilection. Seven percent of infants had siblings with a history of FPIES, and 5% reacted during exclusive breast-feeding. Sixty-eight had a single food trigger (20% had 2 and 12% had ≥3 food triggers). The most common FPIES triggers were rice (45%), cow's milk (33%), and egg (12%). Fifty-one percent of infants reacted on their first known exposure. Infants with FPIES to multiple versus single food groups were younger at the initial episode (4.6 vs 5.8 months [mean], P = .001) and more frequently had FPIES to fruits, vegetables, or both (66% vs 21%, P .0001). Infants exclusively breast-fed for more than 4 months had a trend toward lower rates of FPIES to multiple food groups (23% vs 36%, P = .06). Sixty-four percent of infants with FPIES to multiple foods, which included cow's milk, had coassociated FPIES to solid foods. Forty-two percent of infants with FPIES to fish reacted to other food groups.FPIES is not rare, with an estimated incidence of 15.4/100,000/y. Rice is the most common food trigger in Australia. Factors associated with FPIES to multiple foods included early-onset disease and FPIES to fruits, vegetables, or both.

Previous research has produced conflicting evidence on the preventive effects of early introduction of cow's milk protein on cow's milk allergy (CMA).Through a randomized controlled trial, we sought to determine whether the early introduction of cow's milk formula (CMF) could serve as an effective strategy in the primary prevention of CMA in a general population.We recruited newborns from 4 hospitals in Okinawa, Japan. Participants were randomly allocated to ingest at least10 mL of CMF daily (ingestion group) or avoid CMF (avoidance group) between 1 and 2 months of age. In the avoidance group breast-feeding was supplemented with soy formula as needed. Oral food challenge was performed at 6 months of age to assess CMA development. Continuous breast-feeding was recommended for both groups until 6 months of age.We identified 504 infants for randomization into the 2 groups. In all, the parents of 12 participants declined to receive the intervention, and the study sample comprised 491 participants (242 in the ingestion group and 249 in the avoidance group) for a modified intention-to-treat analysis. There were 2 CMA cases (0.8%) among the 242 members of the ingestion group and 17 CMA cases (6.8%) among the 249 participants in the avoidance group (risk ratio = 0.12; 95% CI = 0.01-0.50; P .001). The risk difference was 6.0% (95% CI = 2.7-9.3). Approximately 70% of the participants in both groups were still being breast-fed at 6 months of age.Daily ingestion of CMF between 1 and 2 months of age prevents CMA development. This strategy does not compete with breast-feeding.

Background Food protein–induced enterocolitis syndrome (FPIES) is a form of non–IgE-mediated gastrointestinal food allergy. Insufficient data exist in regard to gastrointestinal history and outcome, particularly comorbidity, family history, food aversion, and poor body weight gain. Objective We sought to identify the gastrointestinal outcomes and related risk factors in FPIES. Methods We analyzed the clinical features and gastrointestinal outcomes of patients with FPIES retrospectively at 4 hospitals in Boston. Results Two hundred three patients with FPIES were identified, including 180 only with acute FPIES, 8 with chronic FPIES, and 15 with both. Oat (34.5%), rice (29.6%), and cow’s milk (19.2%) were the most common food triggers. The prevalence rates of personal history with allergic proctocolitis (23.2%) and family history with inflammatory bowel diseases (9.4%) and celiac disease (7.3%) were higher than those in the general population. Compared with patients with FPIES with 1 or 2 food triggers, the risk of developing food aversion increased in cases triggered by 3 or more foods (adjusted odds ratio, 3.07; 95% CI, 1.38-6.82; P = .006). The risk of poor body weight gain increased in FPIES triggered by cow’s milk (adjusted odds ratio, 3.41; 95% CI, 1.21-9.63; P = .02) and banana (adjusted odds ratio, 7.63; 95% CI, 2.10-27.80; P = .002). Conclusions Gastrointestinal comorbidities and family history were common in patients with FPIES. Patients with FPIES with 3 or more triggers were at risk of food aversion. Patients with FPIES with cow’s milk and banana as triggers were at risk of poor body weight gain.

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.

In this rostrum we aim to increase awareness of anaphylaxis in infancy in order to improve clinical diagnosis, management, and prevention of recurrences. Anaphylaxis is increasingly reported in this age group. Foods are the most common triggers. Presentation typically involves the skin (generalized urticaria), the respiratory tract (cough, wheeze, stridor, and dyspnea), and/or the gastrointestinal tract (persistent vomiting). Tryptase levels are seldom increased because of infant anaphylaxis, although baseline tryptase levels can be increased in the first few months of life, reflecting mast cell burden in the developing immune system. The differential diagnosis of infant anaphylaxis includes consideration of age-unique entities, such as food protein-induced enterocolitis syndrome with acute presentation. Epinephrine (adrenaline) treatment is underused in health care and community settings. No epinephrine autoinjectors contain an optimal dose for infants weighing 10 kg or less. After treatment of an anaphylactic episode, follow-up with a physician, preferably an allergy/immunology specialist, is important for confirmation of anaphylaxis triggers and prevention of recurrences through avoidance of confirmed specific triggers. Natural desensitization to milk and egg can occur. Future research should include validation of the clinical criteria for anaphylaxis diagnosis in infants, prospective longitudinal monitoring of baseline serum tryptase levels in healthy and atopic infants during the first year of life, studies of infant comorbidities and cofactors that increase the risk of severe anaphylaxis, development of autoinjectors containing a 0.1-mg epinephrine dose suitable for infants, and inclusion of infants in prospective studies of immune modulation to prevent anaphylaxis recurrences.

Background Hen's egg is the most common cause of food allergy in early childhood. Objective We investigated the efficacy and safety of early hen's egg introduction at age 4 to 6 months to prevent hen's egg allergy in the general population. Methods This randomized, placebo-controlled trial included 4- to 6-month-old infants who were not sensitized against hen's egg, as determined based on specific serum antibodies (IgE). These infants were randomized to receive either verum (egg white powder) or placebo (rice powder) added to the first weaning food 3 times a week under a concurrent egg-free diet from age 4 to 6 until 12 months. The primary outcome was sensitization to hen's egg (increased specific serum IgE levels) by age 12 months. Hen's egg allergy (secondary outcome) was confirmed by double-blind, placebo-controlled food challenges. Results Among 406 screened infants, 23 (5.7%) had hen's egg–specific IgE before randomization. Seventeen of 23 underwent subsequent double-blind, placebo-controlled food challenges, and 16 were confirmed as allergic, including 11 with anaphylactic reactions. Of the 383 nonsensitized infants (56.7% male), 184 were randomized to verum and 199 to placebo. At 12 months of age, 5.6% of the children in the verum group were hen's egg sensitized versus 2.6% in the placebo group (primary outcome; relative risk, 2.20; 95% CI, 0.68-7.14; P = .24), and 2.1% were confirmed to have hen's egg allergy versus 0.6% in the placebo group (relative risk, 3.30; 95% CI, 0.35-31.32; P = .35). Conclusion We found no evidence that consumption of hen's egg starting at 4 to 6 months of age prevents hen's egg sensitization or allergy. In contrast, it might result in frequent allergic reactions in the community considering that many 4- to 6-month-old infants were already allergic to hen's egg.

Background: Epidemiological evidence suggests delayed introduction of egg may not protect against egg allergy in infants at risk of allergic disease. Objective: To assess whether dietary introduction of egg between 4-6 months in infants at risk of allergy would reduce sensitization to egg. Methods: We conducted a randomized controlled trial in infants with at least one first-degree relative with allergic disease. Infants with a skin prick test to egg white (EW-SPT)

T U E S D A Y 908 A New Valid and Reliable Parent Proxy Questionnaire to Measure the Impact of Food Protein Enterocolitis Syndrome on Children: The Fpies Quality of Life Questionnaire, Parent Form Jonathan O. Hourihane, MD, FAAAAI, Matthew J. Greenhawt, MD, MBA, MSc, Audrey Dunn Galvin; University College Cork, Cork, Ireland, Department of Internal Medicine, The University of Michigan Medical School, Division of Allergy and Clinical Immunology, Ann Arbor, MI, University College Cork, Ireland. RATIONALE: No tool currently exists to measure health related quality of life (HRQL) in Food Protein Enterocolitis Syndrome (FPIES). We investigated the ability of the Parent Form of Food Allergy Quality of Life Questionnaire (FAQLQ-PF) to accurately assess the impact of FPIES on the HRQL of children, aged 0-12 years. METHODS: 148 European caregivers of children with FPIES completed on-line versions of the FAQLQ-PF and the Food Allergy Independent Measure (FAIM). FAQLQ-PF items were rated for relevance and importance. Participants were asked if any other questions should be included and/or if any of the questions should be reworded. The questions underwent further psychometric analysis including factor analysis and clinical impact methods to modify the items, and scale and item analysis to assess reliability and construct validity. RESULTS: Caregivers of 148 children (62% male) aged between 6 months and 9 years completed the questionnaires. 19 of the 30 items were identified as relevant (Overall Importance Mean 5 2.0). An additional 5 rated as Somewhat Relevant to Relevant (Overall ImportanceMean> 1.5). These were reworded as suggested by participants. Analyses demonstrated high reliability (a5 .92). Bartlett’s test of sphericity, x(45)5 257.3, p

Background Food protein–induced enterocolitis syndrome (FPIES) is a non–IgE-mediated food allergy. FPIES diagnosis is frequently delayed because of the absence of classic allergic symptoms and lack of biomarkers. Objective We sought to characterize the clinical features and resolution of FPIES in patients evaluated in our practice. Methods Subjects 6 months to 45 years of age with FPIES were prospectively recruited for oral food challenges (OFCs). Medical records were searched to identify the subjects who did not participate in OFCs. Results Among 160 subjects, 54% were male; median age at diagnosis was 15 months. We performed 180 OFCs to 15 foods in 82 subjects; 30% of the study population had FPIES confirmed based on OFC results. The most common foods were cow's milk (44%), soy (41%), rice (22.5%), and oat (16%). The majority (65%) reacted to 1 food, 26% reacted to 2 foods, and 9% reacted to 3 or more foods. The majority were atopic, and 39% had IgE sensitization to another food. Thirty-nine (24%) subjects had positive specific IgE levels to the food inducing FPIES. Among children with specific IgE to cow's milk, 41% changed from a milk FPIES to an IgE-mediated phenotype over time. The median age when tolerance was established was 4.7 years for rice, 4 years for oat, and 6.7 years for soy. Median age when milk tolerance was established for subjects with undetectable milk-specific IgE levels was 5.1 years, whereas none of the subjects with detectable milk-specific IgE became tolerant to milk during the study ( P = .003). Conclusion FPIES typically resolves by age 5 years. Milk FPIES, especially with detectable food-specific IgE, can have a protracted course and eventually transition to acute reactions.

Background The prevalence and natural history for food protein–induced enterocolitis syndrome (FPIES) have not been determined. Objective We sought to determine the prevalence, clinical manifestations, and rate of recovery for FPIES in a large-scale, population-based prospective study. Methods In a prospective study the feeding history of 13,019 infants was obtained. Infants with probable adverse reactions to cow's milk protein (CMP) were clinically examined, skin prick tested, and challenged orally. Diagnostic criteria for CMP-induced FPIES included age less than 9 months, delayed recurrent vomiting (usually with nausea), and lethargy after exposure to CMP in the absence of other IgE-mediated symptoms, such as rash, urticaria, and respiratory symptoms. In addition, a positive challenge response to milk resulted in the above-mentioned gastrointestinal symptoms, removal of milk from the diet resulted in the resolution of those symptoms, or both. Results Ninety-eight percent of the cohort participated in the study. The cumulative incidence for FPIES was 0.34% (44/13,019 patients). The most common symptoms were recurrent vomiting (100%), lethargy (77%) diarrhea (25%), pallor (14%), and bloody diarrhea (4.5%). All patients had FPIES within the first 6 months of life. By the age of 3 years, 90% of the patients had recovered. We did not detect any concomitant reaction to soy. Eight patients with FPIES had IgE-mediated cow's milk allergy (IgE-CMA). Conclusions The prevalence of FPIES is significant, and its clinical presentation is distinct from that of IgE-CMA. Most patients with FPIES recover, although a proportion might convert to IgE-CMA. The likelihood for a cross-reactivity to soy in this population was less than previously estimated.

The diversity in the perceived prevalence, recovery, and risk factors for cow's milk allergy (CMA) necessitated a large-scale, population-based prospective study.We sought to determine the prevalence, cross-reactivity with soy allergy, and risk factors for the development of CMA.In a prospective study the feeding history of 13,019 infants was obtained by means of telephone interview (95.8%) or questionnaire (4.2%). Infants with probable adverse reactions to milk were examined, skin prick tested, and challenged orally.Ninety-eight percent of the cohort participated in the study. The cumulative incidence for IgE-mediated CMA was 0.5% (66/13,019 patients). The mean age of cow's milk protein (CMP) introduction was significantly different (P.001) between the healthy infants (61.6 +/- 92.5 days) and those with IgE-mediated CMA (116.1 +/- 64.9 days). Only 0.05% of the infants who were started on regular CMP formula within the first 14 days versus 1.75% who were started on formula between the ages of 105 and 194 days had IgE-mediated CMA (P.001). The odds ratio was 19.3 (95% CI, 6.0-62.1) for development of IgE-mediated CMA among infants with exposure to CMP at the age of 15 days or more (P.001). Sixty-four patients with IgE-mediated CMA tolerated soy, and none had a proved allergy to soy.IgE-mediated CMA is much less common than generally reported. Early exposure to CMP as a supplement to breast-feeding might promote tolerance. Finally, soy is a reasonable feeding alternative in patients with IgE-mediated CMA.