Food-dependent NSAID-induced hypersensitivity (FDNIH) reactions: Unraveling the clinical features and risk factors

Food-triggered anaphylaxis in adults

PURPOSE OF REVIEW

Adult food allergy, either unresolved from childhood, or new-onset in adult-life, is known to be increasingly prevalent. Although much of the reported anaphylaxis in adults is due to drug reactions, foods are becoming an increasingly important trigger, affecting adults of all ages, with a wide variation in food triggers which are often quite different to those reported in children.

RECENT FINDINGS

Peanuts are well known to cause anaphylaxis in some adult populations, but other legumes such as soy may be more relevant in others. Reactions to natto, fermented soybeans, are currently mainly reported in Japan, but changing dietary practices and an increase in plant-based eating mean natto, other forms of soy and other legumes are increasingly linked to anaphylaxis in Western countries. Anaphylaxis to red meat, caused by sensitization to galactose-α-1,3-galactose and first reported in North America, is now a more world-wide concern. Co-factor induced anaphylaxis is increasingly associated with both wheat allergy and lipid transfer protein allergy.

SUMMARY

More research is urgently needed to characterize adult food allergy, its triggers and symptom severity. Unusual food triggers and potential co-factors should be considered, so that anaphylaxis in adults can be correctly managed, not merely labelled as idiopathic.

The management of exercise-induced anaphylaxis in a Chinese child with biologics: a case report

Exercise-induced anaphylaxis (EIA) is a rare and potentially life-threatening disorder. In difficult to control and refractory cases of EIA, biologics such as omalizumab and dupilumab have shown promise, with documented successful outcomes. Here, we present a case of EIA with lipid transfer protein (LTP) sensitization successfully treated with omalizumab with long-term follow-up. A 12-year-old girl presented to our allergy department because of recurrent episodes of EIA, with no specific food ingestion before exercise. Allergen testing revealed sensitization to weed pollens, particularly mugwort (76.1 kUA/L) and Alternaria alternata (10.8 kUA/L). Allergen component testing indicated sensitization to LTP components from mugwort Art v 3 (49.9 kUA/L), wheat Tri a 14 (2.03 kUA/L), and peach Pru p 3 (11.5 kUA/L), with a negative result for omega-5 gliadin. Despite initial prophylactic treatment with budesonide-formoterol (80/4.5 μg) and cetirizine (10 mg) before exercise, the patient still experienced EIA; she was then recommended for dupilumab therapy (an initial dose of 600 mg, followed by 300 mg every 2 weeks for six doses). However, even while undergoing dupilumab therapy, she suffered two anaphylactic episodes after running 800-1,000 m. With the patient's consent, a trial of omalizumab was initiated (injections of 300 mg every 4 weeks). After 2 months of omalizumab therapy, the patient showed significant improvement. She had been engaging in physical exercise three times a week and experienced a mild episode of urticaria. There were no further episodes of anaphylaxis or emergency room visits. By the fourth month of omalizumab treatment, she was able to consume food normally even just before exercising and had returned to her full activity level without any restrictions. This case presents the first successful off-label use of omalizumab in the prevention of EIA in the Chinese population. It is concluded that omalizumab may be helpful in resolving EIA symptoms, as evidenced by this case of successful long-term use.

Food-dependent exercise-induced anaphylaxis (FDEIA) suspected triggered by lipid transfer protein in a Chinese child: A case report

Lipid transfer protein (LTP) has been documented as the dominant protein involved in food-induced anaphylaxis and food-dependent exercise-induced anaphylaxis (FDEIA) patients from Mediterranean European countries. To date, there is no report of FDEIA triggering by LTP in China. A 12-year-old Chinese boy experienced recurrent anaphylaxis during intense exercise for 3 months. Specific immunoglobulin E was performed using ImmunoCAP (Thermo Fisher Scientific, Sweden) and Euroline (EUROIMMUN, Germany). He was sensitized to several pollens, mainly mugwort (62 KUA/L), and was found to have detectable immunoglobulin E in multiple foods: cereal (wheat, barley, oat maize, rice, buckwheat, and common millet), fruits (peach, apple, grape, cherry, and orange), vegetables (lettuce, cabbage, broccoli, cauliflower, tomato, and celery), and legumes and nuts (soybean, peanut, and walnut). He also showed sensitization to LTP components from mugwort Art v3 (79.7 KUA/L) and wheat Tri a14 (12.4 KUA/L), but negative to gluten, gliadin, and omega-5 gliadin. We advised our patient to carry an epinephrine auto-injector, not to exercise alone, and to avoid wheat and fruit/vegetable ingestion for at least 4 hours before exercise or when taking non-steroidal anti-inflammatory drugs. After a 6-month follow-up, the patient has experienced no episode of anaphylaxis. We reported the first documented FDEIA case suspected triggered by LTP in a Chinese child. Clinicians should be aware of LTP sensitization when anaphylaxis occurs during exercise in individuals with multiple pollen and food sensitization.

Blueberry (Vaccinium myrtillus) Induced Anaphylaxis in a Chinese Child with Lipid Transfer Protein Sensitization

Purpose

Fruits have been identified as the primary triggers of anaphylaxis in older children in the Chinese population, especially among individuals with pollen sensitization. To date, no allergies have been reported after blueberry ingestion in the Chinese population.

Case Report

A 12-year-old girl experienced one episode of anaphylaxis within 30 minutes of having breakfast (including milk, egg, wheat bread, and blueberry) while walking to school. She menstruated during this episode. Prompt treatment with epinephrine and fluid therapy led to full recovery within 24 h. Specific IgE was conducted using ImmunoCAP, and the patient exhibited sensitization to several pollens, mainly Japanese hop (74.3 kUa/L) and mugwort (26.5 kUa/L). Regarding specific IgE to allergen components, the patient showed sensitization primarily to lipid transfer protein (LTP) components from mugwort Art v 3 (79.7 kUa/L), wheat Tri a 14 (12.4 kUa/L) and peach Pru p 3 (2.15 kUa/L), but tested negative for omega-5 gliadin. The prick test results were positive for blueberries (wheal size 9.5 mm), cherries (wheal size 6.5 mm), kiwifruits (wheal size 6 mm), and pears (wheal size 4.5 mm). Our patient was provided with an epi-pen and was advised to avoid consuming relevant fruits. After four months of follow-up, the patient had not experienced any episodes of anaphylaxis since these recommendations were implemented.

Conclusion

We report for the first time a Chinese child with severe IgE-mediated immediate-type anaphylactic reaction to blueberries, in whom we identified LTP as the suspected allergen component.

Factors and co-factors influencing clinical manifestations in nsLTPs allergy: between the good and the bad

Non-specific lipid transfer proteins (nsLTPs) are a family of plant pan-allergens that represent the primary cause of food allergies in the Mediterranean area, characterized by a wide range of clinical manifestations, ranging from the total absence of symptoms up to anaphylaxis. This wide variety of symptoms is related to the intrinsic capacity of nsLTPs to cause an allergic reaction in a specific subject, but also to the presence of co-factors exacerbating (i.e., exercise, NSAIDs, PPIs, alcohol, cannabis, prolonged fasting, menstruation, acute infections, sleep deprivation, chronic urticaria) or protecting from (i.e., co-sensitization to PR10, profilin or polcalcin) severe reactions. In this picture, recognizing some nsLTPs-related peculiarities (i.e., route, type and number of sensitizations, concentration of the allergen, cross-reactions) and eventual co-factors may help the allergist to define the risk profile of the single patient, in order to promote the appropriate management of the allergy from dietary advices up to the prescription of life-saving epinephrine autoinjector.

Evaluation and Updated Classification of Acute Hypersensitivity Reactions to Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): NSAID-Exacerbated or -Induced Food Allergy

BACKGROUND

There are hypersensitivity reactions (HRs) to foods in which nonsteroidal anti-inflammatory drugs (NSAIDs) act as aggravating factors (NSAID-exacerbated food allergy [NEFA]) or cofactors (NSAID-induced food allergy [NIFA]), often misdiagnosed as HRs to NSAIDs. Urticarial/angioedematous and/or anaphylactic reactions to two or more chemically unrelated NSAIDs do not meet current classification criteria. However, they may be considered part of a cross-reactive type of acute HR, which is NSAID-induced urticaria/angioedema with or without respiratory or systemic symptoms of anaphylaxis.

OBJECTIVE

To evaluate patients reporting acute HRs to NSAIDs and classify them according to updated criteria.

METHODS

We prospectively studied 414 patients with suspected HRs to NSAIDs. For all whom met these criteria, NEFA/NIFA was diagnosed: (1) mild reactions to (NEFA) or tolerance of (NIFA) the suspected foods without taking NSAIDs; (2) cutaneous and/or anaphylactic reactions to the combination foods plus NSAIDs; (3) positive allergy tests to the suspected foods; and (4) negative drug challenges (DCs) with the NSAIDs involved.

RESULTS

A total of 252 patients were given the diagnosis of NSAID hypersensitivity (60.9%), 108 of whom had NSAID-induced urticaria/angioedema with or without respiratory or systemic symptoms of anaphylaxis. We excluded NSAID hypersensitivity in 162 patients (39.1%) who tolerated DCs with the suspected NSAIDs, nine of whom received a diagnosis of NEFA, and 66 of NIFA. Pru p 3 was implicated in 67 of those 75 patients who received a diagnosis of NEFA or NIFA.

CONCLUSIONS

NEFA and NIFA account for about 18% of patients reporting HRs to NSAIDs, in which Pru p 3 is the main responsible food allergen. Therefore, patients with cutaneous and/or anaphylactic reactions to NSAIDs should be carefully questioned about all foods ingested within 4 hours before or after NSAID exposure, and targeted food allergy tests should be considered in the diagnostic workup of these patients. If testing is positive, DCs with the suspected NSAIDs should also be considered.

Cofactors in food anaphylaxis in adults

Around 25% to 50% of food-induced allergic reactions in adults cause anaphylaxis, and epidemiologic evidence suggests that food is the most common cause of anaphylaxis. Reaction severity is unpredictable, and patients will often experience reactions of variable severity, even to an identical exposure (both dose and allergen). A common explanation for this phenomenon has been the impact of "cofactors"-factors that might contribute to reaction severity independent of the allergen exposure. Cofactors can influence reaction severity in 2 ways: either by reducing the reaction threshold (ie, the dose needed to trigger any symptoms) so that patients have no symptoms in the absence of the cofactor and only react with the cofactor present, or by increasing reaction severity such that individuals have only mild symptoms in the absence of the cofactor, but a more severe reaction when the cofactor is present. Indeed, the same patient may have reactions with different cofactors or even need more than one cofactor to develop a severe reaction. Cofactors reportedly play a role in approximately 30% of anaphylaxis reactions in adults. Exercise, nonsteroidal, anti-inflammatory drugs, alcohol, and sleep deprivation are the most frequent cofactors reported. Routine evaluation of the possible involvement of cofactors is essential in managing patients with food anaphylaxis: in patients with a suggestive history but a negative oral food challenge, cofactors should be taken into account to provide appropriate advice to reduce the risk of future anaphylaxis.

Hidden and Rare Food Allergens in Pediatric Age

In food allergy management, the avoidance of the allergen that caused the reaction plays a fundamental role. Nevertheless, that can be thwarted in case of accidental exposure to a rare or hidden allergen, causing the adoption of a monotonous diet and a consequent reduction in the quality of life of the patient and their family. The identification of a rare and hidden allergen is an important diagnostic challenge, taking into account that a significant proportion of all food reactions is in reality due to them. The aim of the present review is to provide the pediatric allergist an overview of the possible sources of rare and hidden food allergens, taking into consideration the routes of exposure to these potential allergens with the main examples published in the scientific literature and the distinction between types of direct or cross-contamination. The identification of the allergen responsible for the reaction and the provision of a dietary advice customized for the specific individual’s dietary habits is essential to improve quality of life of the familiar nucleus and to reduce the risk of further allergic reactions.

Anaphylaxis across Europe: are pollen food syndrome and lipid transfer protein allergy so far apart?

PURPOSE OF REVIEW

Traditionally pollen-food syndrome (PFS) is considered to be a mild cross-reacting food allergy affecting only Northern Europe, with lipid transfer protein (LTP) allergy being more severe and mainly occurring in Southern Europe. This review seeks to update the reader on both types of plant food allergy and to determine whether the stereotypical presentations of these plant food allergies remain the same, with a particular focus on reaction severity.

RECENT FINDINGS

Recent findings suggest that both these types of plant food allergy occur in children and adults. Although it is true that PFS allergy is more prevalent in Northern Europe and LTP allergy is more well known in Southern Europe, these conditions are not hidebound by geography, and the increasing spread and allergenicity of pollen due to global warming continues to change their presentation. Both conditions have a spectrum of symptom severity, with PFS sometimes presenting with more severe symptoms, including anaphylaxis and LTP allergy with milder reactions.

SUMMARY

It is important to consider that in many parts of Europe, reactions to plant foods, especially fruits or vegetables, could be mediated either by pollen cross-reactivity or primary sensitization to LTP allergens. All those presenting with symptoms to plant foods will benefit from a detailed clinical history and appropriate tests so that an accurate diagnosis can be made, and correct management implemented.

NSAID Hypersensitivity in the Pediatric Population: Classification and Diagnostic Strategies

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently administered drugs, mainly for their anti-pyretic, but also for pain-relieving and anti-inflammatory effects in children. NSAIDs are composed of structurally divergent subgroups of drugs with similar pharmacological and adverse effects. Aspirin originates from salicin and was the first synthesized analgesic. As a prototype of NSAIDs; aspirin-induced hypersensitivity reactions were first reported, but subsequently, other phenotypes of hypersensitivity reactions were also described with aspirin and other NSAIDs. There are certain challenging aspects of NSAID-hypersensitivity in the pediatric population that need to be further investigated. These include the effect of age on drug metabolism and the natural history of the various phenotypes of NSAID-hypersensitivity, the effect of certain co-factors (infections, exercise) on NSAID-hypersensitivity, and diagnostic clinical and laboratory biomarkers clarifying the endotypes. In recent years, a non-negligible number of case series, studies and expert panel reports have been published in this field with some novel features and diagnostic modalities in the pediatric population. With the current review; the clinical phenotypes and diagnostic and management modalities of suspected NSAID-induced hypersensitivity reactions in childhood and adolescence were explained and updated by examining past and current publications.

Advances and highlights in biomarkers of allergic diseases

During the past years, there has been a global outbreak of allergic diseases, presenting a considerable medical and socioeconomical burden. A large fraction of allergic diseases is characterized by a type 2 immune response involving Th2 cells, type 2 innate lymphoid cells, eosinophils, mast cells, and M2 macrophages. Biomarkers are valuable parameters for precision medicine as they provide information on the disease endotypes, clusters, precision diagnoses, identification of therapeutic targets, and monitoring of treatment efficacies. The availability of powerful omics technologies, together with integrated data analysis and network‐based approaches can help the identification of clinically useful biomarkers. These biomarkers need to be accurately quantified using robust and reproducible methods, such as reliable and point‐of‐care systems. Ideally, samples should be collected using quick, cost‐efficient and noninvasive methods. In recent years, a plethora of research has been directed toward finding novel biomarkers of allergic diseases. Promising biomarkers of type 2 allergic diseases include sputum eosinophils, serum periostin and exhaled nitric oxide. Several other biomarkers, such as pro‐inflammatory mediators, miRNAs, eicosanoid molecules, epithelial barrier integrity, and microbiota changes are useful for diagnosis and monitoring of allergic diseases and can be quantified in serum, body fluids and exhaled air. Herein, we review recent studies on biomarkers for the diagnosis and treatment of asthma, chronic urticaria, atopic dermatitis, allergic rhinitis, chronic rhinosinusitis, food allergies, anaphylaxis, drug hypersensitivity and allergen immunotherapy. In addition, we discuss COVID‐19 and allergic diseases within the perspective of biomarkers and recommendations on the management of allergic and asthmatic patients during the COVID‐19 pandemic.

Lipid transfer protein allergy: A review of current controversies

Sensitization to lipid transfer protein (LTP), the most frequent cause of food allergy in southern Europe, still shows several controversial, but also intriguing, aspects. Some of these include the degree of cross-reactivity between LTPs from botanically distant sources, the definition of risk factors, the role of some cofactors, clinical outcomes, geographical differences and the identification of the primary sensitizer in different areas. This review article tries to analyse and comment on these aspects point by point suggesting some explanatory hypotheses with the final scope to stimulate critical thoughts and elicit the scientific discussion about this issue in the readership.

Mechanisms of human drug-induced anaphylaxis

Drug-induced anaphylaxis is a hyperacute reaction affecting multiple organs that can be of fatal consequence. Its incidence is increasing, consistent with a global increased sensitization to various allergens and drugs in the population. Few risk factors and mechanisms have been identified from human studies due to the rarity of anaphylactic events and their unpredictability. This systemic reaction is caused by the rapid release of a large range of functionally diverse mediators, including histamine and platelet-activating factor as the main drivers identified. Mechanisms defined from models of experimental anaphylaxis identify drug-specific antibodies of the IgE and IgG class that link the drug to antibody receptors on multiple cell types, causing their activation and mediator release. In the case of drugs with peculiar chemical structures, antibodies may not be necessary because drug-binding receptors, such as Mas-related G protein-coupled receptor member X2, have been identified. This review describes the complex reaction leading to drug-induced anaphylaxis that can involve various antibody classes, various cell types-including mast cells, neutrophils, platelets, basophils, macrophages, and monocytes-and their mediators and receptors that, importantly, can be activated alone or in association to participate in the severity of the reaction.