Cross-reactive LTP sensitization in food-dependent exercise-induced urticaria/anaphylaxis: a pilot study of a component-resolved and in vitro depletion approach

Abstract

BackgroundChallenge tests for food-dependent exercise-induced anaphylaxis (FDEIA) carry some risk and have a high rate of false negatives. Our aim was to explore the usefulness of an in vitro immunodepletion assay and an allergen microarray test in the identification of IgE-mediated cross-reactive food allergens in patients with suspected FDEIA or food-dependent exercise-induced urticaria and panallergen sensitization.MethodsThree patients with a history of food dependent exercise induced urticaria/anaphylaxis and food panallergen sensitization in whom a food-exercise challenge was not feasible were selected: a 25-year-old man with cholinergic urticaria who experienced generalized urticaria and angioedema during a soccer match after drinking a peach-based soft drink; a 19-year-old woman with allergic rhinitis and controlled asthma who experienced anaphylactic shock while playing soccer, having eaten walnuts in the previous 90 min; and a 57-year-old man with baker’s asthma who experienced four episodes of anaphylaxis during exercise after ingesting wheat-containing food. All individuals underwent a diagnostic work-up with skin prick tests, specific IgE (sIgE) and ImmunoCAP ISAC test. For the in vitro immunodepletion procedure, patients’ serum was pre-incubated with the suspected native allergen (peach, walnut, or wheat) in solid phase (ImmunoCAP). The eluted serum, containing unbound IgE, was collected and samples were re-tested using Immunocap ISAC 112 and compared with baseline results.ResultsAll individuals were sensitized to lipid transfer proteins. The first patient was sensitized to Pru p 3, Cor a 8, Jug r 3, and Ara h 9; after pre-incubation with peach there was 100% depletion of sIgE to all components. The second patient was sensitized to Pru p 3, Cor a 8, Jug r 3, and Ara h 9; immunodepletion with walnut depleted sIgE to Ara h 9 by 67%, Pru p 3 and Pla a 3 (60%), Art v 3 (75%), Jug r 3 (88%), and Cor a 8 (100%). The third patient was sensitized to Pru p 3, Jug r 3, Ara h 9, and Tri a 14; immunodepletion with wheat depleted Tri a 14 only (100%).ConclusionsIn vitro immunodepletion might be a useful diagnostic tool in food dependent exercise induced urticaria/anaphylaxis with panallergen sensitization, particularly for identifying the culprit allergen and guiding dietary elimination recommendations.

Anaphylaxis: A Decade of a Nationwide Allergy Society Registry

“…These results diverge from other European studies,where hazelnut was the most frequent TN [8,24].In a case-series reported from a single center in our country, in Coimbra, TNs were the main cause of FIA in adults, especially walnut and hazelnut [27].By contrast, in arecent study also conducted in our country, involving preschoolers, cashew and walnut were the commonestTNs [26]. LTPsare a common cause of FIA in the Mediterranean area [9,[28][29][30],and have been pointed out as the main elicitor of FDEIA [28,30,31].Food management in these patients is challenging [30][31][32],due to the presence of these panallergens in a great number of plant foods,like fresh fruits, vegetables, TNs and seeds.In studies conducted in Italy [28] and Spain [32], LTPs are reported as the main cause of FIA in adults, especially peach. In this registry, peach is also of particular relevance.…”

“…In a recent study carried out in our country [30],including both children and adults, LTPswerethe third cause of FIA, only preceded by shellfishand CM. In the specific approach to FDEIA, avoidance of the implicated foods for at least 4 hours before exerciseis essential [30,31] and sports should be practiced with a partner capable of administering AAI. DIAwas theleadingcause of anaphylaxis in adults, with NSAIDs predominating over antibiotics, as it has been also reported in studies conducted in Spain [11,33].In this study, a low proportion of DIA was noticed in children, asdescribed by others [8,13,34].NSAIDs were the main cause of DIA, as found in other case-series of nonhospitalized patients [33,35,36];however, in several studies,antibiotics are the first cause of DIA [10, 25,34,37,38],and a high risk of penicillin anaphylaxis is estimated in the general population(0.7 to10%) [38].Among NSAIDs, preferential cyclooxygenase-1 inhibitors were the main implicated, especially ASA, ibuprofen, diclofenac andmetamizole, as found in other case-series [8,17,35,36].Anaphylaxisto selective cyclooxygenase-2 inhibitors NSAIDswas rare, reinforcing these as alternative drugs [17,35,36].…”

Helminth infection induces non-functional sensitization to house dust mites

“…The ImmunoCAP were then centrifuged at 1700g for 2 min and the depleted serum was collected, pooled and immediately tested [11,12].…”

Chronic inducible urticaria: classification and prominent features of physical and non-physical types

“…Patients with cholinergic urticaria that develop hives after exercising or after any other trigger that elevates core body temperature may be at risk of anaphylaxis (18,19). Exercise may trigger urticaria, which may also be an early manifestation of exercise-induced anaphylaxis.…”

“…These increase intestinal permeability and allow increased antigen uptake, thus causing the disease symptoms. Consequently, hives and anaphylaxis occur shortly after patients exercise (19). Prompt treatment is necessary for patients.…”