Anaphylaxis to wheat beer

Detection of Sensitization Profiles with Cellular In Vitro Tests in Wheat Allergy Dependent on Augmentation Factors (WALDA)

Wheat allergy dependent on augmentation factors (WALDA) is the most common gluten allergy in adults. IgE-mediated sensitizations are directed towards ω5-gliadin but also to other wheat allergens. The value of the different in vitro cellular tests, namely the basophil activation test (BAT) and the active (aBHRA) and passive basophil histamine-release assays (pBHRA), in the detection of sensitization profiles beyond ω5-gliadin has not been compared. Therefore, 13 patients with challenge-confirmed, ω5-gliadin-positive WALDA and 11 healthy controls were enrolled. Specific IgE (sIgE), skin prick tests, BATs, aBHRA, and pBHRA were performed with allergen test solutions derived from wheat and other cereals, and results were analyzed and compared. This study reveals a distinct and highly individual reactivity of ω5-gliadin-positive WALDA patients to a range of wheat allergens beyond ω5-gliadin in cellular in vitro tests and SPT. In the BAT, for all tested allergens (gluten, high-molecular-weight glutenin subunits, α-amylase/trypsin inhibitors (ATIs), alcohol-free wheat beer, hydrolyzed wheat proteins (HWPs), rye gluten and secalins), basophil activation in patients was significantly higher than in controls (p = 0.004-p < 0.001). Similarly, significant histamine release was detected in the aBHRA for all test substances, exceeding the cut-off of 10 ng/mL in all tested allergens in 50% of patients. The dependency of tests on sIgE levels against ω5-gliadin differed; in the pBHRA, histamine release to any test substances could only be detected in patients with sIgE against ω5-gliadin ≥ 7.7 kU/L, whereas aBHRA also showed high reactivity in less sensitized patients. In most patients, reactivity to HWPs, ATIs, and rye allergens was observed. Additionally, alcohol-free wheat beer was first described as a promising test substance in ω5-gliadin-positive WALDA. Thus, BAT and aBHRA are valuable tools for the identification of sensitization profiles in WALDA.

Proposal of 0.5 mg of protein/100 g of processed food as threshold for voluntary declaration of food allergen traces in processed food-A first step in an initiative to better inform patients and avoid fatal allergic reactions: A GA²LEN position paper

BACKGROUND

Food anaphylaxis is commonly elicited by unintentional ingestion of foods containing the allergen above the tolerance threshold level of the individual. While labeling the 14 main allergens used as ingredients in food products is mandatory in the EU, there is no legal definition of declaring potential contaminants. Precautionary allergen labeling such as "may contain traces of" is often used. However, this is unsatisfactory for consumers as they get no information if the contamination is below their personal threshold. In discussions with the food industry and technologists, it was suggested to use a voluntary declaration indicating that all declared contaminants are below a threshold of 0.5 mg protein per 100 g of food. This concentration is known to be below the threshold of most patients, and it can be technically guaranteed in most food production. However, it was also important to assess that in case of accidental ingestion of contaminants below this threshold by highly allergic patients, no fatal anaphylactic reaction could occur. Therefore, we performed a systematic review to assess whether a fatal reaction to 5mg of protein or less has been reported, assuming that a maximum portion size of 1kg of a processed food exceeds any meal and thus gives a sufficient safety margin.

METHODS

MEDLINE and EMBASE were searched until 24 January 2021 for provocation studies and case reports in which one of the 14 major food allergens was reported to elicit fatal or life-threatening anaphylactic reactions and assessed if these occurred below the ingestion of 5mg of protein. A Delphi process was performed to obtain an expert consensus on the results.

RESULTS

In the 210 studies included, in our search, no reports of fatal anaphylactic reactions reported below 5 mg protein ingested were identified. However, in provocation studies and case reports, severe reactions below 5 mg were reported for the following allergens: eggs, fish, lupin, milk, nuts, peanuts, soy, and sesame seeds.

CONCLUSION

Based on the literature studied for this review, it can be stated that cross-contamination of the 14 major food allergens below 0.5 mg/100 g is likely not to endanger most food allergic patients when a standard portion of food is consumed. We propose to use the statement "this product contains the named allergens in the list of ingredients, it may contain traces of other contaminations (to be named, e.g. nut) at concentrations less than 0.5 mg per 100 g of this product" for a voluntary declaration on processed food packages. This level of avoidance of cross-contaminations can be achieved technically for most processed foods, and the statement would be a clear and helpful message to the consumers. However, it is clearly acknowledged that a voluntary declaration is only a first step to a legally binding solution. For this, further research on threshold levels is encouraged.

Beer and Allergens

Food allergies are an important global health concern, with many countries following the World Health Organisation’s guidelines with regards to due labelling of foods and, as such, providing forewarning about the presence of potential allergens to potential consumers. While for some produce, the link to specific allergens might be very clear to most consumers, this is not the case for all produce. People with specific food-related allergies usually know what to look out for, but occasionally, unexpected allergens are present in trusted produce. Beer is known to most to contain barley, which will contain gluten-like proteins that can cause allergic reactions in some people. Similarly, beer might contain sulphites and other potential allergens traditionally associated with beers. This review aims to examine a wide range of allergens that have entered the beer production process in recent years. As a result, examples of beers that contain one or more of the 14 EU-UK listed allergens are described, different allergen regulations in different countries are emphasised and their impact explained, and a number of case studies involving allergic reactions following exposure to and the ingestion of beer are highlighted.

Beer: an uncommon cause of anaphylaxis

Beer is one of the most consumed alcoholic beverages worldwide but allergic reactions to this beverage are uncommon. The authors present a case report of a 32-year-old male patient, sent to our Allergy and Immunology Department due to anaphylaxis minutes after Franziskaner beer ingestion. He tolerates all other alcoholic beverages. Prick tests to cereals were positive to wheat, corn and barley, as well as to peach. Prick-to-prick tests were performed with nine beer brands, all positive. Immunoglobulin (Ig)E to Pru p 3 was 14.8 kU/L. Sodium dodecyl sulfate polyacrylamide gel electrophoresis inhibition immunoblotting was performed with the Franziskaner beer extract in solid phase and both cereal extracts (wheat, barley and corn) and Pru p 3 as inhibitors. Extracts from wheat, barley and corn, and Pru p 3 purified protein were able to inhibit almost totally the IgE-binding to the Franziskaner beer extract. It seemed likely that the IgE-binding bands detected in the Franziskaner beer extract could be an LTP from cereals.

Beer anaphylaxis due to coriander as hidden allergen

Beer is one of the most widely consumed alcoholic beverage all over the world. Although the production and consumption of this beverage is diffuse, allergic reactions are very uncommonly reported, mainly due to wheat, yeast or hops allergy. More recently, many foods and drinks have been flavoured with spices, with a reported increase in allergic reactions. We report on a case of a young woman who experienced anaphylaxis due to coriander-flavoured beer. This is the first case of beer anaphylaxis due to coriander, which had been added to the beer as aromatising substance. As the presence of flavours is not always reported, they may be considered hidden allergens, whenever they are the cause of anaphylaxis to foods or beverages, the patient usually tolerated. In conclusion, allergic reactions to spices have to be considered in the patients with 'idiopathic' anaphylaxis induced by common foods, where spices had been hidden.

Case of immediate hypersensitivity to beer

We report here a case of immediate hypersensitivity to beer, in which a female patient developed angioedema of the eyelids shortly after consuming beer. In skin prick tests, the patient showed positive reactions to the base ingredients of beer, particularly malt and barley. The specific serum immunoglobulin E antibodies against barley and malt displayed weakly positive reactivity. To identify the immunoreactive antigens, malt and barley proteins were separated by 2-D polyacrylamide gel electrophoresis and immunoreacted with the patient's serum. The results of mass spectrometric analysis revealed that the main antigen was a protein with similarity to protein z-type serpin. Notably, the identified antigen had a molecular weight of 20-25 kDa, which is markedly smaller than that previously reported for protein Z4 (44 kDa). Taken together, these analyses indicate that a possible new antigen which belongs to the protein Z family elicits immediate hypersensitivity to beer.

Sensitization to beer ingredients in Chinese individuals with beer allergy: a clinical study of 20 cases

BACKGROUND

Rare case reports of allergic reactions to beer have been published, but the nature of the eliciting substances in beer ingredients is often unknown.

OBJECTIVE

It was the aim of this study to identify sensitization patterns against various beer ingredients in Chinese individuals with beer allergy.

METHODS

Twenty-seven Chinese individuals with a clear-cut history of beer allergy were prescreened to answer a specific questionnaire related to the history and symptoms of beer allergy. Twenty individuals underwent allergy diagnostics with different food allergens and extracts of beer ingredients using the skin prick test (SPT) and the open oral provocation test (OPT) with beer.

RESULTS

Fifteen patients (75%) showed positive reactions to one or more beer ingredients. Of these, 9 individuals, reactive to sorghum and/or sorghum malt also showed positive reactions to other ingredients. Seventeen individuals showed variable symptoms after the OPT. Cutaneous erythema and urticaria were the most common symptoms and usually persisted for over 2 h. There were no significant differences in SPT reactivity to beer ingredients between male and female individuals. Single patients reacted to barley, hops or yeast.

CONCLUSIONS

Sensitization to sorghum and/or sorghum malt was the most common finding in Chinese individuals with beer allergy.