Faculty Bibliography

Food protein-induced enterocolitis syndrome (FPIES) is a non IgE-mediated gastrointestinal food allergy that presents with delayed vomiting after ingestion primarily in infants. While the pathophysiology of FPIES is poorly understood, the clinical presentation of acute FPEIS reactions has been well characterized. The first International Consensus Guidelines for the Diagnosis and Management of Food Protein-induced Enterocolitis Syndrome were published in 2017 and reviewed epidemiology, clinical presentation, and prognosis of acute and chronic FPIES. The workgroup outlined clinical phenotypes, proposed diagnostic criteria, and made recommendations on management. This article summarizes the guidelines and adds recent updates. FPIES is gaining recognition, however there continues to be delays in diagnosis and misdiagnosis due to overlap of symptoms with over conditions, lack of a diagnostic test, and because some of the common trigger foods are not thought of as allergenic. More research into disease mechanisms and factors influencing differences between populations is needed.

Background/UNASSIGNED:Naturally occurring botulism is rare, but a large number of cases could result from unintentional or intentional contamination of a commercial food. Despeciated, equine-derived, heptavalent botulinum antitoxin (HBAT) is licensed in the United States. Timely treatment reduces morbidity and mortality, but concerns that botulinum antitoxin can induce anaphylaxis exist. We sought to quantify the allergy risk of botulinum antitoxin treatment and the usefulness of skin testing to assess this risk. Methods/UNASSIGNED:We conducted a systematic review of (1) allergic reactions to botulinum antitoxin and (2) the predictive value of skin testing (ST) before botulinum antitoxin administration. We searched 5 scientific literature databases, reviewed articles' references, and obtained data from the HBAT manufacturer and from the Centers for Disease Control and Prevention. Anaphylaxis incidence was determined for HBAT and previously employed botulinum antitoxins. We calculated the positive predictive value (PPV) and negative predictive value (NPV) of ST for anaphylaxis related to HBAT and other botulinum antitoxins. Results/UNASSIGNED:Seven articles were included. Anaphylaxis incidence was 1.64% (5/305 patients) for HBAT and 1.16% (8/687 patients) for all other botulinum antitoxins (relative risk, 1.41 [95% confidence interval, .47-4.27]; P = .5). Observed values for both PPV and NPV for HBAT-ST (33 patients) were 100%. Observed PPVs and NPVs of ST for other botulinum antitoxins (302 patients) were 0-56% and 50%-100%, respectively. There were no reports of fatal anaphylaxis. Conclusions/UNASSIGNED:Considering the <2 % rate of anaphylaxis, fatal outcomes, modest predictive value of ST, resource requirements for ST, and the benefits of early treatment, data do not support delaying HBAT administration to perform ST in a mass botulinum toxin exposure. Anaphylactic reactions may occur among 1%-2% of botulinum antitoxin recipients and will require epinephrine and antihistamine treatment and, possibly, intensive care.

PURPOSE OF REVIEW/OBJECTIVE:We focus on recent advances regarding the epidemiology, physiopathology, diagnosis and managements of non-IgE-mediated gastrointestinal food allergies (non-IgE-GI-FAs), particularly food protein-induced enterocolitis syndrome (FPIES). RECENT FINDINGS/RESULTS:The first international FPIES diagnostic and management guidelines have been recently published. Although FPIES largely remains a diagnosis of exclusion, it may be more prevalent than previously thought. Ondansetron has emerged as a major tool for the treatment of FPIES acute reactions. Recent data also suggest an important role for innate immune cells in FPIES pathogenesis. SUMMARY/CONCLUSIONS:Despite major advances in the diagnosis and management of non-IgE-GI-FAs, particularly FPIES, the lack of specific diagnostic tests and biomarkers to guide clinical management remains challenging.

Food allergy develops as a consequence of a failure in oral tolerance, which is a default immune response by the gut-associated lymphoid tissues to ingested antigens that is modified by the gut microbiota. Food allergy is classified on the basis of the involvement of IgE antibodies in allergic pathophysiology, either as classic IgE, mixed pathophysiology or non-IgE-mediated food allergy. Gastrointestinal manifestations of food allergy include emesis, nausea, diarrhoea, abdominal pain, dysphagia, food impaction, protein-losing enteropathy and failure to thrive. Childhood food allergy has a generally favourable prognosis, whereas natural history in adults is not as well known. Elimination of the offending foods from the diet is the current standard of care; however, future therapies focus on gradual reintroduction of foods via oral, sublingual or epicutaneous food immunotherapy. Vaccines, modified hypoallergenic foods and modification of the gut microbiota represent additional approaches to treatment of food allergy.

Results from the Learning Early About Peanut trial and its follow-up study suggest that early peanut introduction in the diets of high-risk infants may prevent the development of peanut allergy. Allergy organizations around the world released a unified statement, the Consensus Communication on Early Peanut Introduction and the Prevention of Peanut Allergy in High Risk Infants, in response to results from the Learning Early About Peanut trial, which recommends early introduction of peanut into the diet of those children at greatest risk of development of peanut allergy. As a result, it is expected that practicing allergists will experience an increased demand to perform an oral food challenge (OFC) in infants. Allergists often perform OFCs; however, conducting an OFC in an infant creates unique circumstances that have not been considered in previously published OFC guideline documents. The purpose of this workgroup report is to provide guidance to practitioners regarding the proper approach for conducting a peanut challenge in an infant.