Interdisciplinary Significance of Food-Related Adverse Reactions in Adulthood

[Differential diagnosis in food allergy]

It is important to establish the differential diagnosis of food allergy with other disorders, for example: toxic reactions that occur in any person exposed to a sufficient amount of some allergen, and non-toxic reactions that depend on individual susceptibility (food allergy or intolerance). The differential diagnosis is decisive to establish the appropriate treatment. Food intolerance involves adverse reactions to foods without any immunological response involved, and commonly manifests with gastrointestinal symptoms (malaise, abdominal pain or diarrhea). Food allergy is an exaggerated reaction of the immune system, often mediated by IgE, that can trigger serious symptoms (hives, inflammation, respiratory distress, even anaphylaxis). The complex thing is because the symptoms sometimes overlap. To establish an accurate diagnosis, exhaustive clinical evaluation, laboratory tests and, in some cases, controlled provocation tests are required. It is important to understand these distinctions, because treatment and management vary significantly. Food intolerance involves the elimination or reduction of the food that triggers the allergic reaction and requires rigorous measures (complete avoidance of the allergen and availability of epinephrine in cases of severe reactions).

Outcomes of oral food challenges in a real-world setting, with predictors of outcomes

BACKGROUND

Oral food challenge (OFC) remains the reference standard for food allergy (FA) diagnosis.

OBJECTIVE

This study reports a single-center observational experience with all OFCs conducted over 3 years.

METHODS

All OFCs performed at an outpatient office were tracked. The OFCs were conducted without strict prespecified inclusion or exclusion criteria. Demographic information along with results of diagnostic testing and results of the OFCs were recorded.

RESULTS

A total of 1132 OFCs were performed, with a median age of 4 years (interquartile range = 2.0-10.0). Of the 1132 OFCs, 862 (76.1%) tolerated the food, whereas 232 (20.5%) experienced a reaction, and 38 (3.4%) did not complete the OFC because of food refusal. The highest percentage of tolerated food was shellfish (91.1%), with the lowest percentage of tolerated food being baked egg (66.1%). There were 66 (5.8%) OFCs that were deemed to be high risk, of which 35 (53.0%) tolerated the food. More than 50% of reactions occurred on the first or second dose, with the most common clinical symptom being urticaria or angioedema, with 29.2% of reactions treated with epinephrine. There were several factors that predicted tolerating an OFC, including the food challenge, the reason for food avoidance, older age at the time of OFC and less reactive skin prick testing, and lower food-specific immunoglobulin E levels.

CONCLUSION

Certain factors can predict tolerating an OFC, and even those considered to be high risk can be safely completed in an outpatient setting, with most tolerating the food, and most reactions not requiring treatment with epinephrine.

Hypersensitivity reactions amongst Hungarian Patients with Hereditary Angioedema due to C1-Inhibitor Deficiency

Background

In hereditary angioedema (HAE) due to C1-inhibitor deficiency (C1-INH-HAE), bradykinin-mediated submucosal and/or subcutaneous angioedema dominates the clinical picture. The deficiency of C1-inhibitor can lead to the over-activation of the complement system. Complement plays an important role in all types of hypersensitivity reactions. On the other hand, during the degranulation of mast cells, heparin is also released amongst other substances. Heparin can activate the plasma kinin-kallikrein system, leading to bradykinin generation. These observations suggest a possible connection between C1-INH-HAE and mast cell-mediated hypersensitivity reactions.

Objective

To assess the occurrence of hypersensitivity reactions in the Hungarian C1-INH-HAE population.

Methods

Patients filled out a questionnaire of 112 questions, either online or on paper. The questions were about hypersensitivity and C1-INH-HAE symptoms, the relation between these 2, general health, and demographic data. The study protocol was approved by the institutional review board of Semmelweis University, Budapest, and informed consent was obtained from the participants.

Results

One hundred and six patients (64 female, 42 male, median age 46 years) responded, with 63.2% having hypersensitivity. Hypersensitivity was provoked by pollen in 25.5% of patients, by contact sensitivity in 22.6%, by food in 21.7%, by insect sting in 19.8%, by pet in 15.1%, by drug in 14.2%, by dust mite in 5.7%, and by mold in 1.9%. In 11 patients, hypersensitivity symptoms appeared after the diagnosis of C1-INH-HAE. Six hypersensitive patients experienced improvement in their symptoms; 42 remained the same, but none experienced worsening after the diagnosis of C1-INH-HAE. In 7.8% of the hypersensitive patients, a C1-INH-HAE attack worsened the hypersensitivity symptoms, while 15.7% of the hypersensitive patients experienced a C1-INH-HAE attack provoked by contact with the provoking factor.

Conclusion

While 63.2% of our C1-INH-HAE patients have reported hypersensitivity symptoms, Eurostat's latest data puts the prevalence of self-reported allergies in Hungary at 19.3%. Since in our experience most Hungarian patients report hypersensitivity reactions as allergies, this may support a possible connection between the 2 diseases, but further molecular studies are needed.

The effect of beetroot juice on airway inflammation in a murine model of asthma

The effects of beetroot juice on airways inflammation, cytokine levels, and oxidative stress biomarkers were evaluated using an allergen-induced murine model of asthma. Ovalbumin (OVA)-sensitized and challenged BALB/c mice were used as an asthma model. BALB/c mice were randomly assigned into four groups: control (Ova sensitization and normal saline challenge), control and beetroot (Ova sensitization and normal saline challenge plus beetroot juice), Ova S/C [Ova sensitization and challenge (Ova S/C)], Ova S/C and beetroot juice (Ova S/C plus beetroot juice). The bronchoalveolar lavage fluid (BALF) was analyzed for total and differential inflammatory cells count. The levels of cytokines [interleukin (IL)-10, IL-13, and IL-18], and oxidative stress biomarkers [glutathione peroxidase (GPx), catalase, and thiobarbituric acid reactive substances (TBARS)] were analyzed in the lung tissue. Simultaneous administration of beetroot juice and Ova S/C significantly increased the total inflammatory cells compared to the control (p = .0001) and Ova S/C (p = .013) groups and significantly increased the number of eosinophils (p ˂ .0001) and macrophages (p ˂ .0001) compared to the control. Moreover, the simultaneous administration of beetroot juice and Ova S/C did not affect the level of IL-10, IL-13, IL-18, GPx, or TBARS compared to the control (p > .05), but it significantly increased the level of catalase (p = .002). Results suggest that beetroot juice aggravates asthma by enhancing airway inflammation. However, it does not affect airway inflammation in healthy mice. PRACTICAL APPLICATIONS: Asthma is a chronic airway inflammatory disease that is characterized by variable degrees of airways inflammation and obstruction. Paradox data are reported in the literature regarding beetroot and asthma. The present study revealed that beetroot juice exacerbates asthma by enhancing airway inflammation. However, it is safe and has no effects on airway inflammation in healthy mice. Patients having asthma or a history of asthma are advised to avoid the consumption of beetroot.

Allergen Tests of Fruit Sensitization Involving Children with Allergic Diseases

Fruit is a kind of plant food which is rich in nutrients and immune-regulating ingredients. A meta-analysis has demonstrated that fruits have a protective effects against asthma. On the other hand, clinical syndromes of allergic reactions to fruits manifest as an oral allergy syndrome. We aimed to investigate the patterns and associated factors of fruit allergen-specific IgE (sIgE) sensitization among patients with suspected clinical symptoms. Data were extracted from the Chang Gung Research Database. Fruit sensitization in Taiwan was evaluated using the presence of IgE antibodies against specific fruits. The overall prevalence of positive sIgE responses to fruit allergens in Taiwan, in order of decreasing importance, was pineapple, kiwi, banana, and papaya. Children aged 0–18 had a higher positive rate of allergic responses to pineapple, kiwi, banana, and papaya than adults over the age of 18. Positive specific IgE for kiwi, banana, or papaya was more frequent in younger than in older children and children with a higher total IgE of both logarithmic (log) and arithmetic values. The analysis of log IgE for pineapple positive vs. negative children determined an optimal cutoff value, log IgE 2.2, with both sensitivity (0.9) and specificity (0.5). Dermatitis was significantly more prevalent in children with positive IgE for pineapple, kiwi, banana, and papaya than negative specific IgE. The highest positive rate of sIgE against fruits was pineapple among children. Even in older children, the positive rate of pineapple allergens was high. IgE discriminates with and without sIgE for pineapple, with an optimal cutoff of 158.5 U/mL.

Histamine Intolerance Originates in the Gut

Histamine intolerance (HIT) is assumed to be due to a deficiency of the gastrointestinal (GI) enzyme diamine oxidase (DAO) and, therefore, the food component histamine not being degraded and/or absorbed properly within the GI tract. Involvement of the GI mucosa in various disorders and diseases, several with unknown origin, and the effects of some medications seem to reduce gastrointestinal DAO activity. HIT causes variable, functional, nonspecific, non-allergic GI and extra-intestinal complaints. Usually, evaluation for HIT is not included in differential diagnoses of patients with unexplained, functional GI complaints or in the here-listed disorders and diseases. The clinical diagnosis of HIT is challenging, and the thorough anamnesis of all HIT-linked complaints, using a standardized questionnaire, is the mainstay of HIT diagnosis. So far, DAO values in serum have not been established to correlate with DAO activity in the gut, but the diagnosis of HIT may be supported with determination of a low serum DAO value. A targeted dietary intervention, consisting of a histamine-reduced diet and/or supplementation with oral DAO capsules, is helpful to reduce HIT-related symptoms. This manuscript will present why histamine should also be taken into account in the differential diagnoses of patients with various diseases and disorders of unknown origin, but with association to functional gastrointestinal complaints. In this review, we discuss currently increasing evidence that HIT is primarily a gastrointestinal disorder and that it originates in the gut.