Stephanie A. Leonard

Dietary baked egg accelerates resolution of egg allergy in children

BACKGROUNDnBaked egg is tolerated by a majority of egg-allergic children.nnnOBJECTIVEnTo characterize immunologic changes associated with ingestion of baked egg and evaluate the role that baked egg diets play in the development of tolerance to regular egg.nnnMETHODSnEgg-allergic subjects who tolerated baked egg challenge incorporated baked egg into their diet. Immunologic parameters were measured at follow-up visits. A comparison group strictly avoiding egg was used to evaluate the natural history of the development of tolerance.nnnRESULTSnOf the 79 subjects in the intent-to-treat group followed for a median of 37.8 months, 89% now tolerate baked egg and 53% now tolerate regular egg. Of 23 initially baked egg-reactive subjects, 14 (61%) subsequently tolerated baked egg and 6 (26%) now tolerate regular egg. Within the initially baked egg-reactive group, subjects with persistent reactivity to baked egg had higher median baseline egg white (EW)-specific IgE levels (13.5 kU(A)/L) than those who subsequently tolerated baked egg (4.4 kU(A)/L; P= .04) and regular egg (3.1 kU(A)/L; P= .05). In subjects ingesting baked egg, EW-induced skin prick test wheal diameter and EW-, ovalbumin-, and ovomucoid-specific IgE levels decreased significantly, while ovalbumin- and ovomucoid-specific IgG(4) levels increased significantly. Subjects in the per-protocol group were 14.6 times more likely than subjects in the comparison group (P< .0001) to develop regular egg tolerance, and they developed tolerance earlier (median 50.0 vs 78.7 months; P< .0001).nnnCONCLUSIONnInitiation of a baked egg diet accelerates the development of regular egg tolerance compared with strict avoidance. Higher serum EW-specific IgE level is associated with persistent baked and regular egg reactivity, while initial baked egg reactivity is not.

Oral immunotherapy induces local protective mechanisms in the gastrointestinal mucosa

BACKGROUNDnOral immunotherapy (OIT) is a promising treatment for food allergy. Studies are needed to elucidate mechanisms of clinical protection and to identify safer and potentially more efficacious methods for desensitizing patients to food allergens.nnnOBJECTIVEnWe established a mouse model of OIT to determine how the dose or form of antigen may affect desensitization and to identify mechanisms of desensitization.nnnMETHODSnIncreasing doses of egg white or ovomucoid as OIT were administered orally to sensitized mice. The impact of OIT on anaphylaxis elicited by oral allergen challenge was determined. Allergen-specific antibody and cytokine responses and mast cell and basophil activation in response to OIT were measured. Gene expression in the small intestine was studied by microarray and real-time PCR.nnnRESULTSnOIT resulted in desensitization but not tolerance of mice to the allergen. OIT did not result in desensitization of systemic effector cells, and protection was localized to the gastrointestinal tract. OIT was associated with significant changes in gene expression in the jejunum, including genes expressed by intestinal epithelial cells. Extensively heated ovomucoid that does not trigger anaphylaxis when given orally to sensitized mice was as efficacious as native ovomucoid in desensitizing mice.nnnCONCLUSIONSnOIT results in clinical protection against food-induced anaphylaxis through a novel mechanism that is localized to the intestinal mucosa and is associated with significant changes in small intestinal gene expression. Extensively heating egg allergen decreases allergenicity and increases safety while still retaining the ability to induce effective desensitization.

Food protein-induced enterocolitis syndrome: an update on natural history and review of management.

OBJECTIVESnTo review the clinical features, pathophysiology, and management of food protein-induced enterocolitis syndrome (FPIES) and to discuss new observations in epidemiology and natural history.nnnDATA SOURCESnPubMed searches were performed for articles published between 1978 and May 2011 using the keywords food-induced enterocolitis and FPIES.nnnSTUDY SELECTIONnArticles were selected based on their relevance to the topic of this review. The newest developments in FPIES were defined by articles published in the past 3 years.nnnRESULTSnFPIES is a non-IgE-mediated gastrointestinal food hypersensitivity thought to be cell-mediated, although the exact pathophysiologic mechanism requires further study. In a recent birth cohort, the incidence of cows milk FPIES was 0.34% in the first year of life compared with 0.5% for IgE-mediated cows milk allergy. FPIES typically presents before 6 months of age in formula-fed infants with repetitive emesis, diarrhea, dehydration, and lethargy 1 to 5 hours after ingesting the offending food. Four cases of FPIES in breastfed infants have recently been reported. The most common offending foods are cows milk, soy, and rice. Diagnosis is based primarily on clinical history and, when unclear, physician-supervised oral food challenges. FPIES is usually outgrown by school age. Although management remains avoidance of the offending food, observations that natural history varies for different foods has redefined the timing of reintroduction.nnnCONCLUSIONnEarly recognition of FPIES and removal of the offending food are imperative to prevent misdiagnosis and mismanagement of symptoms that may mimic other causes. Close follow-up is required to determine when foods may be added back into the diet.

International consensus guidelines for the diagnosis and management of food protein-induced enterocolitis syndrome: Executive summary-Workgroup Report of the Adverse Reactions to Foods Committee, American Academy of Allergy, Asthma & Immunology.

&NA; Food protein–induced enterocolitis (FPIES) is a non‐IgE cell‐ mediated food allergy that can be severe and lead to shock. Despite the potential seriousness of reactions, awareness of FPIES is low; high‐quality studies providing insight into the pathophysiology, diagnosis, and management are lacking; and clinical outcomes are poorly established. This consensus document is the result of work done by an international workgroup convened through the Adverse Reactions to Foods Committee of the American Academy of Allergy, Asthma & Immunology and the International FPIES Association advocacy group. These are the first international evidence‐based guidelines to improve the diagnosis and management of patients with FPIES. Research on prevalence, pathophysiology, diagnostic markers, and future treatments is necessary to improve the care of patients with FPIES. These guidelines will be updated periodically as more evidence becomes available.

Clinical diagnosis and management of food protein-induced enterocolitis syndrome.

Purpose of review To provide an overview of clinical manifestations, diagnosis and pathophysiology of food protein-induced enterocolitis syndrome (FPIES), an under-recognized and often misdiagnosed nonimmunoglobulin E-mediated food hypersensitivity. This review will highlight updates on natural history and clinical management. Recent findings The main developments in FPIES involve epidemiology, common presentation and variants thereof, and natural history. Improved understanding and recognition of FPIES have influenced changes in clinical management. Summary A large prospective population-based study reported cows milk-FPIES cumulative incidence to be 0.34% by 1 year of age; immunoglobulin E-mediated cows milk allergy was 0.5%. A case report has suggested that FPIES pathophysiology involves Th2 activation, and a shift away from Th2 signalling may be associated with resolution. Appreciation of the frequent incidence of multiple food-FPIES has influenced anticipatory guidance. Two case reports have described FPIES to food proteins in maternal breast milk. The threshold dose for FPIES reactivity may decrease with successive episodes. Reports from different populations indicate that children may outgrow FPIES sooner than previously thought.

Manifestations, Diagnosis, and Management of Food Protein-Induced Enterocolitis Syndrome

CME EDUCATIONAL OBJECTIVES 1. Recognize manifestations, diagnosis, and management of food protein-induced enterocolitis syndrome (FPIES) in an outpatient setting. 2. Assess nutritional needs and provide anticipatory guidance for dietary management. 3. Recognize the indications of when to refer for assessment of resolution of FPIES using physician-supervised food challenges. Food protein-induced enterocolitis syndrome (FPIES) is an under-recognized non-immunoglobulin E (IgE)-mediated gastrointestinal food allergy affecting primarily infants and toddlers. An abnormal response to food antigen resulting in local inflammation is thought to lead to increased intestinal permeability and fluid shift. The primary features of acute FPIES are repetitive, projectile vomiting, lethargy, pallor, diarrhea, and dehydration. Chronic FPIES is typically seen in young infants with continued exposure to cows milk or soy-based formula. Biomarkers are lacking and patients may undergo extensive workups for their symptoms, which often leads to a delay in diagnosis and puts infants at risk for feeding difficulties, nutritional deficiencies, and failure to thrive. This review will provide a guide in how to recognize the clinical features of and manage FPIES.

In vitro assessment of the allergenicity of novel MF59-adjuvanted pandemic H1N1 influenza vaccine produced in dog kidney cells.

A licensed inactivated MF59-adjuvanted seasonal influenza vaccine (Optaflu) produced in canine kidney cells (MDCK 33016-PF) contained no egg proteins and did not trigger degranulation in rat basophilic leukemia (RBL) cells passively sensitized with human anti-dog IgE, supporting its safe use in dog-allergic individuals. The cell-derived pandemic H1N1 influenza vaccine was also adjuvanted with the emulsion adjuvant MF59, and support for its similar safe use was sought. We sought to evaluate in vitro allergenicity of the MF59-adjuvanted cell-derived pandemic H1N1 influenza vaccine in subjects with dog allergy, with a mediator release assay. RBL-2H3 cells transfected with human Fcε receptor type 1 were sensitized with sera from adult dog-allergic subjects and stimulated with serial dilutions of pandemic H1N1 influenza vaccine and dog dander extract. β-N-hexosaminidase release (NHR) was used as a marker of RBL degranulation.. Median dog dander-specific IgE in 30 dog-allergic subjects was 27.7 kUA/L (range 10.1; >100); and in 5 dog non-allergic subjects was

Less Air Pollution Leads to Rapid Reduction of Airway Inflammation and Improved Airway Function in Asthmatic Children

Renzetti G, Silvestre G, DAmario C, et al. Pediatrics. 2009;123(3):1051–1058nnPURPOSE OF THE STUDY. To investigate whether relocating children with asthma from an environment of high pollution to one of low pollution has an effect on short-term airway inflammation.nnSTUDY POPULATION. This was a case study of 37 children, ≥7 years of age, with untreated, mild, persistent asthma who were recruited from an urban asthma clinic in Italy and followed at a rural school camp for 1 week. The children came from homes that had implemented dust mite precautions, and they stayed in a …

Reduced Occurrence of Early Atopic Dermatitis Because of Immunoactive Prebiotics Among Low-Atopy-Risk Infants

C Gruber, M van Stuijvenberg, F Mosca; MIPS 1 Working Group. J Allergy Clin Immunol. 2010;126(4):791–797nnTo determine whether the supplementation of prebiotics and immunoactive oligosaccharides can prevent the development of atopic dermatitis in infants.nnTerm weaned infants younger than 8 weeks without a family history of atopy in a parent or sibling were recruited from several northern European study centers.nnThis was a double-blind, placebo-controlled, randomized, prospective study. Infants were randomly assigned to the prebiotics group (PG), control group (CG), or exclusively breastfed group (BG). Infants in the PG received a nonhydrolyzed cows milk–based formula with a specific mixture of short- and long-chain oligosaccharides (ratio 9:1, 85% of mixture) and pectin-derived acidic oligosaccharides (15% …

Food Protein-Induced Enterocolitis Syndrome: 16-Year Experience

Mehr S, Kakakios A, Frith K, Kemp AS. Pediatrics. 2009;123(3). Available at: www.pediatrics.org/cgi/content/full/123/3/e459nnPURPOSE OF THE STUDY. To investigate possible patterns in demographic features, causative foods, clinical features, treatments at presentation, and outcomes in children diagnosed with food protein-induced enterocolitis syndrome (FPIES).nnSTUDY POPULATION. Retrospective chart review of 35 children who presented with acute FPIES at a tertiary medical center in New South Wales, Australia, between 1992 and 2007.nnMETHODS. Diagnosis was made by pediatric allergists after referral to the allergy clinic (74%) or from the emergency department (ED) (26%), using previously published criteria. Cases were identified by codes signifying allergic and dietetic gastroenteritis and colitis or by …