Oral food challenge to wheat: a near-fatal anaphylaxis and review of 93 food challenges in children.

BACKGROUND: Wheat allergy is among the most common food allergy in children, but few publications are available assessing the risk of anaphylaxis due to wheat. METHODS: In this study, we report the case of near-fatal anaphylaxis to wheat in a patient undergoing an oral food challenge (OFC) after the ingestion of a low dose (256 mg) of wheat. Moreover, for the first time, we analyzed the risk of anaphylaxis during an OFC to wheat in 93 children, compared to other more commonly challenged foods such as milk, egg, peanuts, and soy in more than 1000 patients. RESULTS: This study, which includes a large number of OFCs to wheat, shows that wheat is an independent risk factor that is associated with anaphylaxis requiring epinephrine administration (Odds Ratio [OR] = 2.4) and anaphylaxis requiring epinephrine administration to low dose antigen (OR = 8.02). Other risk factors for anaphylaxis, anaphylaxis requiring epinephrine administration, and anaphylaxis to low dose antigen was a history of a prior reaction not involving only the skin (OR = 1.8, 1.9 and 1.8 respectively). None of the clinical variables available prior to performing the OFC could predict which children among those undergoing OFCs to wheat would develop anaphylaxis or anaphylaxis for low dose antigen. CONCLUSION: This study shows that wheat is an independent risk factor that is associated with anaphylaxis requiring epinephrine administration and anaphylaxis requiring epinephrine administration to low dose antigen.

Biphasic reactions in children undergoing oral food challenges.

Literature regarding biphasic reactions in the pediatric population is sparse. We aimed to determine the prevalence of biphasic reactions in children with food allergies undergoing oral food challenges (OFCs) and examine whether any clinical or treatment factors are associated with biphasic reactions. A retrospective chart review of OFCs conducted between July 2007 and March 2011 was performed. Charts were reviewed from time of challenge to 48 hours after challenge to capture data on any biphasic reactions. Uniphasic and biphasic reactions were compared in terms of specific clinical features and treatments. Of 614 positive challenges, 9 resulted in a biphasic reaction (1.5%). Six of the biphasic reactions occurred in challenges where the initial reaction met anaphylaxis criteria. The biphasic reactions were to eggs (4), peanuts (3), and milk (2). The symptom-free interval ranged from 2 to 24 hours. There were no statistically significant differences in clinical features between uniphasic and biphasic reactions, but there appeared to be a higher percentage of initial reactions with multiple organ involvement and meeting anaphylaxis criteria in the biphasic group. Biphasic reactors were significantly more likely to have received steroids for their initial reaction. A higher percentage of biphasic reactors also appeared to have received epinephrine, multiple doses of epinephrine, and antihistamines for their initial reactions. Biphasic reactions are rare in children undergoing OFCs and may be associated with more severe allergic reactions. Children with severe reactions may benefit from a 24-hour period of observation.

Asthma and frequency of wheeze: risk factors for the persistence of atopic dermatitis in children.

BACKGROUND: Studies have examined the development of asthma in children with atopic dermatitis (AD); however, none have looked at the association of asthma or the frequency of wheeze with respect to persistence or difficulty in achieving AD clinical improvement in children. OBJECTIVE: To determine whether children with AD who have asthma and increasing frequency of wheezing have more persistent AD. METHODS: This is a cohort study using the Pediatric Eczema Elective Registry (PEER) database, which includes data obtained at enrollment and 3 years later. The AD outcome was the persistence of skin symptoms. Our covariates of interest were asthma diagnosis and wheezing symptoms, which were measured at enrollment and again at year 3 of the study. Multivariate logistic regression models assessed the magnitude of associations among AD symptoms, asthma diagnosis, and the frequency of wheeze. All models were adjusted for sex, age, and ethnicity. RESULTS: A total of 2104 children were enrolled in the PEER study and had at least 3 years of follow-up at the time of this study. At enrollment, an asthma diagnosis decreased the likelihood of being rash free in the preceding 6 months by 30% (odds ratio, 0.70; 95% confidence interval, 0.59-0.84). At year 3, having asthma decreased the likelihood by 40% (odds ratio, 0.60; 95% confidence interval, 0.49-0.72). Increasing frequency of wheezing also decreased the likelihood that a child was rash free (P < .001). CONCLUSION: For children with AD, a history of asthma and an increasing frequency of wheezing correlate strongly with more persistent AD.

Do bugs control our fate? The influence of the microbiome on autoimmunity.

Autoimmune disease has traditionally been thought to be due to the impact of environmental factors on genetically susceptible individuals causing immune dysregulation and loss of tolerance. However, recent literature has highlighted the importance of the microbiome, (a collective genome of microorganisms in a given niche) in immune homeostasis. Increasingly, it has been recognized that disruptions in the commensal microflora may lead to immune dysfunction and autoimmunity. This review summarizes recent studies investigating the interplay between the microbiome and immune-mediated organ-specific diseases. In particular, we review new findings on the role of the microbiome in inflammatory bowel disease, celiac disease, psoriasis, rheumatoid arthritis, type I diabetes, and multiple sclerosis.

Predictive values for food challenge-induced severe reactions: development of a simple food challenge score.

BACKGROUND: Skin-prick tests (SPT), food-specific immunoglobulin E level (sIgE) and clinical history have limited value individually in predicting the severity of outcome of the oral food challenge (OFC). OBJECTIVES: To develop a score that accounts for SPT, sIgE and clinical history to predict the risk of severe reaction to the OFC. METHODS: A 5 year retrospective chart review was performed on 983 children who underwent OFC to egg, milk and peanut. RESULTS: Using multilogistic regression, four major indicators were found to be independently associated with failed OFC: sIgE (odds ratio = 1.04, P < 0.0001), wheal size of the SPT (OR = 1.23, P < 0.0001), a history of any prior reaction to the food (OR = 1.13, P < 0.01), and a history of a prior non-cutaneous reaction (OR = 1.99, P < 0.01); and three were independently associated with anaphylaxis: wheal size (OR = 1.16, P < 0.001), a history of a prior non-cutaneous reaction (OR = 4.24, P < 0.01), and age (OR = 1.07, P < 0.03). A Food Challenge Score (0-4) was developed which accounted for SPT wheal, sIgE, a history of a prior non-cutaneous reaction, and age. A score of 0-1 had a negative predictive value for multisystem reaction to the OFC: 95% for milk, 91% for egg and 93% for peanut. A score of 3-4 had a positive predictive value for anaphylaxis: 62% for milk, 92% for egg and 86% for peanut. CONCLUSIONS: Severe reaction to milk, egg and peanut OFC can be predicted using a simple score that takes into account clinical data that are commonly available prior to the challenges.

Presentation of hemophagocytic lymphohistiocytosis due to a novel MUNC 13-4 mutation masked by partial therapeutic immunosuppression.

Hemophagocytic lymphohistiocytosis is a potentially fatal disease characterized by excessive macrophage and lymphocyte activity. Patients can be affected following immune activation after an oncologic, autoimmune or infectious trigger. An associated gene mutation may be found which impairs cytolytic lymphocyte function. We describe a pediatric case of hemophagocytic lymphohistiocytosis with a novel mutation of MUNC 13-4 whose diagnosis was confounded by concurrent immunosuppression. Clinical reassessment for hemophagocytic lymphohistiocytosis is necessary in persistently febrile patients with laboratory derangements in the setting of immunosuppressive agent exposure.