Prevalence, clinical presentation, and associated atopic diseases of pediatric fruit and vegetable allergy: A population-based study

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.

Fruit allergy and anaphylaxis in children: Culprit fruits and clinical findings

Background: Fruit allergy usually presents with mild-to-moderate symptoms but serious systemic reactions, e.g., anaphylaxis, may also occur. Objective: This study aimed to examine the clinical and laboratory characteristics of patients with fruit allergy and fruit-induced anaphylaxis. Methods: Patients diagnosed with fruit allergy at Dışkapı Hematology and Oncology Hospital and Bilkent City Hospital between January 2017 and January 2023 were included in the study. The diagnosis of anaphylaxis was made according to the European Allergy and Clinical Immunology Anaphylaxis Guideline. Results: During the study period, skin-prick tests with food allergens were performed on 9432 patients in our clinic, and fruit allergy was detected in 78 patients (0.82%). Five patients with inaccessible medical records were excluded from the study. 40 (54.8%) were boys. The median (interquartile range) age at the onset of symptoms was 72 months (12.5-144 months). Sixty-eight of the patients (93.2%) had a concomitant allergic disease, the most common of which was allergic rhinitis (n = 48 [65.8%]). The 73 patients had a history of reaction to 126 fruits. Twenty-five patients (19.8%) were allergic to multiple fruits. The most common fruit allergen was banana (22/126 [17.4%]), followed by peach (18/126 [14.2%]) and kiwi (17/126 [13.5%]). Mucocutaneous findings were observed most frequently after fruit consumption (120/126 [95.2%]). Anaphylaxis occurred in 17 patients (23.2%) with 21 fruits.The fruits most commonly associated with anaphylaxis were banana (6/21 [28.6%]) and kiwi (6/21 [28.6%]). Conclusion: Fruit allergy generally presents with mild symptoms, e.g., oral allergy syndrome, but severe systemic symptoms, e.g., anaphylaxis, can also be observed. Kiwi and banana are the fruits that most commonly cause anaphylaxis. Although more comprehensive studies are needed to comment on the development of tolerance, especially in patients with anaphylaxis, responsible fruit avoidance is still the most important strategy.

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.

A comprehensive review on mango allergy: Clinical relevance, causative allergens, cross-reactivity, influence of processing techniques, and management strategies

Mangoes (Mangifera indica) are widely prized for their abundant nutritional content and variety of beneficial bioactive compounds and are popularly utilized in various foods, pharmaceuticals, and cosmetics industries. However, it is important to note that certain proteins present in mango can trigger various allergic reactions, ranging from mild oral allergy syndrome to severe life-threatening anaphylaxis. The immunoglobulin E-mediated hypersensitivity of mango is mainly associated with three major allergenic proteins: Man i 1 (class IV chitinase), Man i 2 (pathogenesis-related-10 protein; Bet v 1-related protein), and Man i 4 (profilin). Food processing techniques can significantly affect the structure of mango allergens, reducing their potential to cause allergies. However, it is worth mentioning that complete elimination of mango allergen immunoreactivity has not been achieved. The protection of individuals sensitized to mango should be carefully managed through an avoidance diet, immediate medical care, and long-term oral immunotherapy. This review covers various aspects related to mango allergy, including prevalence, pathogenesis, symptoms, and diagnosis. Furthermore, the characterization of mango allergens and their potential cross-reactivity with other fruits, vegetables, plant pollen, and seeds were discussed. The review also highlights the effects of food processing on mango and emphasizes the available strategies for managing mango allergy.

Elimination diet in food allergy: friend or foe?

OBJECTIVES

To review and discuss the role of an elimination diet in food-allergic children, emphasizing nutritional aspects for a better practical approach.

SOURCES

Non-systematic review of the literature.

FINDINGS

Under an elimination diet, food-allergic patients may suffer from growth impairment or obesity and compromised quality of life. Disease phenotype, age, type, number of foods excluded, comorbidities, eating difficulties, economic status, and food availability must be considered for an appropriate diet prescription. Diet quality encompasses diversity and degree of food processing, which may alter immune regulation.

CONCLUSIONS

A friendly food elimination diet prescription depends on a multidisciplinary approach beyond macro and micronutrients.

Complementary Feeding Practices: Recommendations of Pediatricians for Infants with and without Allergy Risk

AIM

To investigate the routine guidance provided by pediatricians concerning the timing of complementary feeding (CF) for both healthy infants and those at a heightened risk of allergies.

METHODS

A total of 233 pediatricians participated in an anonymous online survey that included questions about demographics and recommendations for CF. Specifically, they provided guidance on the types of foods, preparation methods, supplements, time intervals for introducing new foods to infants at low and high allergy risk, and delayed food introductions for high-risk cases.

RESULTS

The respondents advised introducing certain foods at specific ages: fruits, starchy non-gluten grains, vegetables, olive oil, and meat were appropriate at 6 months; gluten-rich grains at 7 months; yogurt, hard-boiled eggs, and legumes at 8 months; fish at 8.5 months; and nuts at 9 months. Pediatricians, especially those with less than 15 years of practice, often introduced egg, seafood, gluten-rich grains, legumes, and nuts earlier for high-risk infants. Parenthood and male gender were associated with the earlier introduction of eggs and grains.

CONCLUSIONS

Greek pediatricians follow a structured food introduction schedule for CF in infants. Interestingly, they tend to delay the introduction of common food allergens and recommend longer intervals between introducing new foods, particularly for high-risk infants. Key Notes: Despite recent evidence-based indications on healthy complementary feeding strategies for infants, discrepancies persist among pediatricians regarding food choices and the order and timing of food introduction, both for healthy infants and those at risk of allergy. Guidance on complementary feeding by pediatricians is influenced by their individual characteristics. Pediatricians tend to delay the introduction of common food allergens and recommend longer intervals between introducing new foods, particularly for high-risk infants.

Revisiting Fruit Allergy: Prevalence across the Globe, Diagnosis, and Current Management

Fruit allergies manifest with a diverse array of clinical presentations, ranging from localized contact allergies and oral allergy syndrome to the potential for severe systemic reactions including anaphylaxis. The scope of population-level prevalence studies remains limited, largely derived from single-center or hospital-based investigations. In this comprehensive review, we conducted a systematic literature search spanning the years 2009 to 2023, with full acknowledgment of potential analytical biases, to provide a global overview of fruit allergy prevalence. The primary mechanistic underpinning of fruit allergies stems from cross-reactivity between aeroallergens and food allergens, a consequence of structurally similar epitopes-a phenomenon recognized as pollen food allergy syndrome (PFAS). In the era of molecular allergology, numerous studies have dissected allergen components with substantial clinical relevance. Within this review, we explore important allergenic molecules found in plant-based foods, scrutinize pertinent cross-reactivity patterns, and offer insights into management recommendations. Additionally, we compare guideline recommendations to enhance clinical understanding and inform decision making.

Allergic sensitization to foods in India and other Low-Middle-income countries

Food allergy is an important cause of morbidity, significantly affecting the quality of life of the sufferer. Most food allergy research has been undertaken in high-income countries. Here, we summarize literature regarding food allergy in India and other low-middle-income countries (LMIC). We provide summaries of self-reported adverse food reactions and food sensitization in these regions by reviewing published community-based studies of prevalence, burden, and risk factors. We identified 2 community-based studies of food allergy prevalence in Karnataka, India, which estimate that food allergy affects just 0.14% of children and 1.2% of adults. The overall prevalence of allergic sensitization to 'any' food was 26.5% in adults and 19.1% in children by serum-specific IgE; but only 4.48% in children by skin prick test. We identified a further 28 studies in other LMICs, mainly from China but also Turkey, South Africa, Ghana, Mexico, Brazil, Thailand, Philippines, and Korea. The overall prevalence of allergic sensitization to 'any' food ranged from 0.11% to 16.8% in children using serum-specific IgE and 0.14% to 9.6% in children by skin prick test. The questionnaires and skin prick testing materials used and number of allergens tested varied significantly between studies. Other than Karnataka, there is no information on prevalence of food sensitization and probable food allergy in the community in India. Similar lack of information is noted among the majority of the 136 LMICs. Where community-based studies have been undertaken, there is wide variation in the prevalence and patterns of food sensitization across different LMICs, at least partly due to variations in study methodology. International collaboration is required in order to formally assess food allergy prevalence and burden across representative samples from multiple LMICs.