Food-Pollen Cross-Reactivity and its Molecular Diagnosis in China.

PURPOSE OF REVIEW: Plant-derived foods are one of the most common causative sources of food allergy in China, with a significant relationship to pollinosis. This review aims to provide a comprehensive overview of this food-pollen allergy syndrome and its molecular allergen diagnosis to better understand the cross-reactive basis. RECENT FINDINGS: Food-pollen cross-reactivity has been mainly reported in Northern China, Artemisia pollen is the major related inhalant source, followed by tree pollen (Betula), while grass pollen plays a minor role. Pollen allergy is relatively low in Southern China, with allergies to grass pollen being more important than weed and tree pollens. Rosaceae fruits and legume seeds stand out as major related allergenic foods. Non-specific lipid transfer protein (nsLTP) has been found to be the most clinically relevant cross-reacting allergenic component, able to induce severe reactions. PR-10, profilin, defensin, chitinase, and gibberellin-regulated proteins are other important cross-reactive allergen molecules. Artemisia pollen can induce allergenic cross-reactions with a wide range of plant-derived foods in China, and spring tree pollens (Betula) are also important. nsLTP found in both pollen and plant-derived food is considered the most significant allergen in food pollen cross-reactivity. Component-resolved diagnosis with potential allergenic proteins is recommended to improve diagnostic accuracy and predict the potential risk of causing allergic symptoms.

Neglected but Clinically Relevant Allergens in Korea.

PURPOSE OF REVIEW: Allergy diagnostics and immunotherapeutics in Asia heavily rely on imported products from Western countries, raising concerns about the accuracy and efficacy of these products for the management of Asian allergy patients. RECENT FINDINGS: Recent advancements in allergen research have led to the identification and characterization of novel allergens from indigenous Korean species. While some allergens share homology with well-known allergens, others lack counterparts in imported allergen extracts. Classifying regional allergens in Asia into three categories based on their cross-reactivity with imported allergens offers valuable insights. Highly cross-reactive allergens, such as oak allergens Que m 1 from Quercus mongolica and Que ac 1 from Q. acutissima, can be effectively substituted with the imported allergens. Allergens with partial cross-reactivity, like the Asian needle ant allergen Pac c 3 (Antigen 5), permit limited diagnostic value by the currently available products. Unique allergens, including the Japanese hop allergen Hum j 6 (pectin methylesterase inhibitor) and the silkworm pupa allergen Bomb m 4 (30 kDa hemolymph lipoprotein) lack alternatives in the available product list. Greater attention is needed, particularly for species listed as ecologically invasive in Western regions. Additionally, allergens from domestic fruits and vegetables causing pollen food allergy syndrome require characterization for the development of improved diagnostics.

Outcomes of apple oral immunotherapy in pollen food allergy syndrome.

Oral immunotherapy with apple induces tolerance for an entire apple (128 g) in patients with pollen food allergy syndrome who previously tolerated a median amount of 4 g of apple.

Pollen food allergy syndrome secondary to molds and raw mushroom cross-reactivity: a case report.

BACKGROUND: Pollen food allergy syndrome (PFAS) is an immunoglobulin E (IgE) mediated reaction that causes oropharyngeal pruritus or angioedema due to homologous proteins present in the culprit food as well as a sensitizing aeroallergen. This cross-reactivity has been well established between pollen and fruits/vegetables. Given the evolutionary similarity between all fungi; cross-reactivity between spore forming microfungi and edible macrofungi have been suggested, however only a limited number of case reports have ever been published on this phenomenon. We present a case of a patient who experiences pollen food allergy syndrome-like symptoms following lightly cooked mushroom ingestion who otherwise was able to tolerate cooked mushrooms. We then review the literature to highlight the limited studies of an underrecognized PFAS cross-reactivity between molds and mushrooms. CASE PRESENTATION: A 15-year-old male presents with symptoms of seasonal and perennial allergic rhinitis was found to have multiple environmental sensitizations to molds via skin prick testing (C. gramineum, A. Pullulans and B. cinerea) and ImmunoCAP serum-specific IgE (A. alternata, C. herbarum, and P. notatum). He developed throat pruritus and subjective throat tightness following ingestion of mushroom containing pizza. ImmunoCAP serum specific IgE to whole mushroom was negative but fresh food prick testing to fresh portobello mushroom and cremini mushroom were both positive with a negative test to canned mushroom. The patient then underwent a graded oral challenge and successfully tolerated canned mushrooms. CONCLUSION: This case highlights the potential cross-reactivity between microfungi aeroallergens and edible fungi, leading to PFAS-like reactions in susceptible individuals. The patient's ability to tolerate canned mushrooms suggests a possible heat-labile protein as the cause of the reaction, similar to PFAS patients tolerating cooked but not raw fruits/vegetables. Positive skin prick test to both spore-forming fungi and edible fungi with negative and whole mushroom IgE results further support the hypothesis of cross-reactivity and sensitization. Further research is needed to identify the specific allergenic proteins involved in these cross-reactions and the susceptible species of mold and mushroom. Understanding these components will contribute to improved diagnosis and management of mold and mushroom allergies, and enhance our knowledge of allergenic cross-reactivity in general.

Profiles of apple allergen components and its diagnostic value in Northern China.

Background: Limited is known on the profiles of apple allergy in China. Objective: To explore the clinical significance of apple allergen components in northern China. Methods: This study recruited 40 participants and categorized into apple tolerance (n = 19) and allergy (n = 21) group. The latter was categorized into oral allergy symptoms (OAS, n = 14) and generalized symptoms (GS, n = 7). All participants underwent ImmunoCAP screening to assess sIgE levels of birch, apple, and their components. Results: The sensitization rates were 90% for Bet v 1, 85% for Mal d 1, 35% for Bet v 2, and 20% for Mal d 3. The overall positive rate for apple allergens was 97.5%, with half demonstrating mono-sensitization to Mal d 1. Birch, Bet v 1 and Mal d 1 sIgE levels had consistent areas under the curve (AUC 0.747, p = 0.037; AUC 0.799, p = 0.012; AUC 0.902, p < 0.001 respectively) in diagnosing apple allergy. The optimal cut-off values were determined to be 22.85 kUA/L (63.6% sensitivity, 85.7% specificity), 6.84 kUA/L (81.8% sensitivity, 71.4% specificity) and 1.61 kUA/L (93.8% sensitivity, 75.0% specificity), respectively. No allergens or components demonstrated diagnostic value in distinguishing between OAS and GS. Mal d 3 sensitization was correlated with mugwort allergy and higher risk of peach, nuts or legumes generalized allergy. Conclusion: Mal d 1 was major allergen and the best for diagnosing apple allergy. Mal d 3 does not necessarily indicate severe allergic reaction to apples in northern China but may indicate mugwort sensitization and an increased risk of peach, nuts or legumes allergy.

Allergen Component Testing: Key in Diagnosing Atypical Pollen-Food Allergy Syndrome.

This case report details the complex presentation, diagnosis, and management of a teenager with pollen-food allergen syndrome (PFAS), formerly known as oral allergy syndrome. PFAS, mediated by immunoglobulin E (IgE) antibodies, stems from the cross-reactivity between pollens and uncooked plant-based foods, leading to a spectrum of symptoms, such as itching or tingling of the oral cavity. A UK survey indicated an average PFAS prevalence of 2%, with apples, hazelnuts, and kiwifruit commonly implicated. The presented case involved a 15-year-old girl referred from the respiratory clinic to the allergy clinic due to episodes of sore throat and urticaria rash following Nutella (chocolate paste containing hazelnut) and peanut consumption. Extensive diagnostic measures, including specific IgE testing, skin prick tests, and allergen component testing, revealed cross-reactivity between Bet v 1 and hazelnut allergens. The patient's atopic history, encompassing poorly controlled asthma, allergic rhinitis, and eczema, added layers of complexity to the diagnosis. Management strategies comprised dietary advice, allergen avoidance, and potential consideration of aeroallergen immunotherapy. A comprehensive dietary plan emphasized abstaining from specific foods and raising awareness of potential reactions. The patient, following guidance from the allergy clinic, exhibited improvements in allergic rhinitis and oral symptoms. This case underscores the importance of allergen component testing in diagnosing atypical PFAS presentations and tailoring management plans. Ongoing collaboration between healthcare providers, detailed patient education, and regular follow-ups are crucial for effective PFAS management and long-term care.

The effect of subcutaneous and sublingual birch pollen immunotherapy on birch pollen-related food allergy: a systematic review.

Background: Birch pollen-related food allergy (BPFA) is the most common type of food allergy in birch-endemic areas such as Western and Central Europe. Currently, there is no treatment available for BPFA. Due to the cross-reactivity between birch pollen and a range of implicated plant foods, birch pollen allergen immunotherapy (AIT) may be effective in the treatment of BPFA. In this study, we systematically evaluate the effectiveness of birch pollen-specific subcutaneous or sublingual immunotherapy in treating BPFA. Methods: A search was performed in the PubMed, Embase, and Cochrane libraries. Studies were independently screened by two reviewers against predefined eligibility criteria. The outcomes of interest were changes in (1) severity of symptoms during food challenge, (2) eliciting dose (ED), and (3) food allergy quality of life (FA-QoL). The validity of the selected articles was assessed using the revised Cochrane risk of bias tool. We focused on studies with the lowest risk of bias and considered studies with a high risk of bias as supportive. Data were descriptively summarized. Results: Ten studies were selected that included 475 patients in total. Seven studies were categorized into "high risk of bias" and three into "moderate risk of bias." The three moderate risk of bias studies, with a total of 98 patients, reported on severity of symptoms during challenge and on the ED. All three studies had a control group. Compared to the control group, improvement in severity of symptoms was observed during challenge in two out of the three studies and on the eliciting dose in one out of three. Only one study investigated the effect of birch pollen AIT on FA-QoL, showing that there was no significant difference between patients receiving subcutaneous immunotherapy or a placebo. Of the seven supportive studies, four had a control group and of those, three showed improvement on both severity of symptoms and ED. None of the supportive studies investigated the effect of the therapy on FA-QoL. Conclusion: This systematic review shows that there is not enough evidence to draw firm conclusions about the effect of AIT on BPFA. Future research is warranted that uses robust clinical studies that include long-term effects, QoL, and multiple BPFA-related foods.

[Epidemiology of food allergy]. / Epidemiología de la alergia alimentaria.

Food allergy is very common throughout the world and has become a major public health problem, with 220 million people suffering from it. Food allergy has been disproportionately observed in people from industrialized or Western countries and was previously considered to predominate in the pediatric versus adult population. However, the current exponential growth of the adult population and older adults, especially in Western countries, and environmental and lifestyle changes, have profoundly changed the epidemiology of food allergy, with a growing increase even at advanced ages. The foods that represent the greatest severity and clinical impact are peanuts, walnuts, fish, shellfish, eggs, cow's milk protein, wheat, soy and seeds. Although some types of food allergies (cow's milk and egg) may disappear, peanut and tree nut allergies may persist into adulthood. The control or cure of cow's milk protein allergy is gradual throughout childhood and adolescence. Despite the predominance of allergy to fish, shellfish, peanuts, and tree nuts in most reactions in adults, the most common form of IgE-mediated food allergy is oral allergy syndrome or pollen allergy syndrome. food.

La alergia alimentaria es muy común en todo el mundo y se ha convertido en un importante problema de salud pública, pues 220 millones de personas la padecen. La alergia alimentaria se ha observado de manera desproporcionada en personas de países industrializados u occidentales, y se considera previamente con predominio en la población pediátrica versus adultos. Sin embargo, el crecimiento exponencial actual de la población adulta y adultos mayores, especialmente en los países occidentales, y los cambios ambientales y de estilo de vida, han cambiado profundamente la epidemiología de la alergia alimentaria, con un aumento creciente incluso en edades avanzadas. Los alimentos que representan mayor gravedad y repercusión clínica son: cacahuate, nuez, pescado, mariscos, huevo, proteína de leche de vaca, trigo, soya y semillas. Aunque algunos tipos de alergia alimentaria (leche de vaca y huevo) pueden desaparecer, la alergia al cacahuete y la nuez de árbol pueden persistir hasta la edad adulta. El control o curación de la alergia a la proteína de leche de vaca es gradual a lo largo de la niñez y la adolescencia. A pesar del predominio de la alergia al pescado, mariscos, cacahuates y nueces de árbol en la mayoría de las reacciones en adultos, la forma más común de alergia alimentaria mediada por IgE en es el síndrome de alergia oral o síndrome de alergia al polen-alimento.