OBJECTIVES: To analyze the potential causal relationship between gut microbiota and food allergy (FA) using two-sample Mendelian randomization (MR) methods. METHODS: Data from genome-wide association studies on gut microbiota and FA were utilized. MR analysis was conducted employing inverse variance weighting, MR-Egger regression, and weighted median methods to assess the causal relationship between gut microbiota and FA. Cochrane's Q test was used to evaluate heterogeneity of instrumental variables, MR-PRESSO analysis was conducted to test for outliers and pleiotropy, and MR-Egger regression was employed to assess horizontal pleiotropy. The "leave-one-out" method was used to evaluate the impact of removing individual single nucleotide polymorphisms on the causal relationship. RESULTS: Inverse variance weighting analysis revealed that the phylum Verrucomicrobia, family Verrucomicrobiaceae, order Verrucomicrobiales, genus Ruminococcaceae UCG013, and genus Akkermansia were negatively associated with FA (P<0.05). Sensitivity analyses confirmed the reliability of the findings, indicating no heterogeneity or pleiotropy present. CONCLUSIONS There is a causal relationship between gut microbiota and FA, with Verrucomicrobia, Verrucomicrobiaceae, Verrucomicrobiales, Ruminococcaceae UCG013, and Akkermansia potentially reducing the risk of developing FA. These findings provide potential targets for the treatment and prevention of FA; however, further research is needed to explore the specific mechanisms by which the microbiota influence FA.
Humans ; Mendelian Randomization Analysis ; Gastrointestinal Microbiome ; Food Hypersensitivity/microbiology* ; Genome-Wide Association Study ; Polymorphism, Single Nucleotide

OBJECTIVES: To investigate the effect of interleukin-17 (IL-17) gene polymorphism on the susceptibility to cow's milk protein allergy (CMPA) in infants and its association with gut microbiota. METHODS: A prospective study was conducted involving 100 infants diagnosed with CMPA at the Women and Children's Hospital of Ningbo University from January 2022 to October 2024. A total of 100 healthy infants undergoing routine check-ups at the same hospital during the same period was enrolled as the control group. Medical information was obtained through the electronic medical record system. IL-17A (rs2275913) and IL-17F (rs1889570) polymorphisms were detected using polymerase chain reaction-restriction fragment length polymorphism method. Serum IL-17 levels were measured using enzyme-linked immunosorbent assay, and high-throughput sequencing was employed to analyze the relative abundance of Lactobacillus and Bifidobacterium. Multivariate logistic regression analysis was used to explore the influencing factors of CMPA occurrence in infants. RESULTS: The proportions of infants with a family history of allergy and those with vitamin D deficiency or insufficiency were significantly higher in the CMPA group compared to those in the control group (P<0.05). The distribution of IL-17F (rs1889570) genotypes showed significant differences between the CMPA and control groups (P<0.05), with the frequency of the A allele being significantly higher in the CMPA group (P<0.05). Multivariate logistic regression analysis revealed that a family history of allergy, vitamin D deficiency or insufficiency, and carrying the IL-17F (rs1889570) AA genotype were independent influencing factors for CMPA in infants (P<0.05). Infants in the CMPA group with the IL-17F (rs1889570) AA genotype had significantly higher serum IL-17 levels compared to those with AG/GG genotypes (P<0.05), while the relative abundance of Lactobacillus and Bifidobacterium was significantly lower (P<0.05). CONCLUSIONS IL-17F (rs1889570) gene polymorphism influences susceptibility to CMPA in infants, potentially through mechanisms involving IL-17 expression and the relative abundance of gut probiotics.
Humans ; Interleukin-17/genetics* ; Milk Hypersensitivity/microbiology* ; Female ; Infant ; Male ; Prospective Studies ; Genetic Predisposition to Disease ; Gastrointestinal Microbiome ; Polymorphism, Genetic ; Milk Proteins/immunology*

Objective:To investigate the clinical characteristics and major allergens of patients with pollen-food allergy syndrome（PFAS） and their correlation with the severity of symptoms, and to provide a basis for identifying high-risk patients, optimizing the allergen testing process and developing individualized dietary management strategies. Methods:The clinical data of 166 patients with PFAS admitted to our hospital from January 2021 to July 2023 were retrospectively analyzed. The clinical symptoms, pollen types and food allergy of the patients were analyzed by questionnaire survey and serum specific IgE detection. phi coefficient, Apriori algorithm modeling and multivariate logistic regression analysis were used to evaluate the association between allergen and symptom severity. Results:Artemisia pollen was the most common allergen in this area, with a positive rate of 96.39%. Peach and mango were the most common food allergens, which caused allergic reactions in 24.10% and 22.89% of patients, respectively. Oral mucosal symptoms were the main symptoms. Correlation analysis showed that there was a correlation between pollen allergens and allergenic food. Association rule analysis showed that when the patient was allergic to the combination of peanuts and trees, the probability of high severity of symptoms was 82.35%. Multivariate analysis showed that ragweed allergy was significantly positively correlated with the severity of PFAS symptoms. Conclusion:Artemisia pollen and related food allergens play an important role in the pathogenesis of PFAS. Association rule mining and network map analysis revealed direct associations between peanut and tree combination allergy and symptom severity, as well as potential links between other inhaled allergens and specific food allergies. Ragweed and peach allergy are independent risk factors for the aggravation of PFAS symptoms, which can be used as early warning indicators. These results help to improve the screening of high-risk patients and the construction of regional allergen databases.
Humans ; Food Hypersensitivity/immunology* ; Allergens/immunology* ; Retrospective Studies ; Pollen/immunology* ; Cross Reactions ; Immunoglobulin E/blood* ; Rhinitis, Allergic, Seasonal/immunology* ; Artemisia/immunology* ; Male ; Female ; Adult ; Prunus persica/immunology* ; Arachis/immunology* ; Middle Aged ; Surveys and Questionnaires ; Oral Allergy Syndrome

Animals ; Cattle ; Female ; Milk Hypersensitivity/therapy* ; Consensus ; Immunoglobulin E ; Milk Proteins

BACKGROUND: Recent studies indicate that the timing of introduction of potentially allergenic food is crucial for the development of food allergy in children. This cross-sectional study aimed to clarify the reality of allergen food intake in a general population of young children in Japan. METHODS: A questionnaire survey of caregivers was conducted at health checkups for 1.5-year (18-month)-old and 3-year-old children in the fall of 2020. The caregivers were asked about (1) the presence/absence of allergic disease symptoms based on the ISAAC questionnaire, and (2) foods that caregivers avoided giving their children. Ordinal logistic regression analyses were periformed to determine factors associated with food avoidance. RESULTS: Questionnaires were distributed to 1720 caregivers, and 1603 (93%) responded. The responders consisted of 771 and 832 caregivers who participated in 1.5-year-old and 3-year-old checkups, respectively. The prevalence of allergic diseases was comparable to recent epidemiological studies in Japan, indicating that the population may be representative. At 1.5 years old, more than 50% of the children were not exposed to peanuts, tree nuts, fish eggs, shellfish, and buckwheat. At 3 years old, the avoidance rates of the foods had decreased but were still between 18.8% and 32.0%. On the other hand, the avoidance rates of chicken egg and cow's milk, the top 2 common allergenic foods in Japan, were much lower at 2.8% and 1.5% at 1.5 years, and they decreased to 1.4% and 0.7% at 3 years old, respectively. Ordinal logistic analysis showed that avoidance of chicken egg, cow's milk, and wheat was associated with food allergy diagnosis and chicken egg avoidance with eczema, but avoidance of other foods showed no associations with any risk factors for food allergy. CONCLUSION Caregivers avoided giving various foods, independent of allergy risk factors, to their young children. Since delayed introduction of an allergenic food has been reported to increase the risk of developing an allergy to the food, the results warrant future investigation of the development of food allergies in relation to current eating habits and recommendations.
Female ; Animals ; Cattle ; Humans ; Cross-Sectional Studies ; Japan/epidemiology* ; Food Hypersensitivity/complications* ; Risk Factors ; Food ; Allergens

There are many types in food allergy, and the most common is mediated by IgE. Currently, the diagnosis of food allergy mainly relied on skin prick test and serum specific IgE of allergen extract, which can not identify cross-sensitization. Component-resolved diagnosis (CRD) can identify the major allergen components and cross-components of food allergens, which plays an important role in dietary guidance, prognosis monitoring and diagnosis of special types of IgE-mediated food allergy. This article enumerates clinical characteristics of the IgE-mediated common food allergies, such as milk, egg and seafood allergy, and special type of food allergy, such as cat pork syndrome, oral allergy syndrome, α-gal syndrome and food-dependent exercise-induced anaphylaxis, summarizes the advances of CRD in these types of IgE-mediated food allergy, in order to provide an evidence for the diagnosis, treatment and prevention of IgE-mediated food allergy.
Humans ; Allergens ; Immunoglobulin E ; Food Hypersensitivity/diagnosis* ; Skin Tests

Oral allergy syndrome (OAS) is an IgE-mediated hypersensitivity. Patients with pollen allergy will experience oropharyngeal allergy after eating fresh fruits or vegetables containing homologous pathogenesis-related allergen, occasionally accompanied by systemic symptoms, it is a special type of food hypersensitivity in which respiratory allergens and food allergens are similar structurally and lead to the cross-reactivity. At present, there is little research and attention to it in China. To master the definition, epidemiological characteristics, pathological mechanism, diagnosis, prevention and treatment of OAS is very important to the prevention and control of OAS. This article reviews the research progress of OAS, providing reference and prevention basis for clinicians to improve the diagnosis and differential diagnosis of OAS.
Humans ; Pollen ; Food Hypersensitivity/diagnosis* ; Rhinitis, Allergic, Seasonal/therapy* ; Allergens ; Fruit ; Cross Reactions

Objective: To investigate the clinical characteristics of children with allergic diseases suffering from SARS-CoV-2 Omicron variant strains. Methods: This was a cross-sectional study. A total of 43 pediatric patients with allergic diseases infected by SARS-CoV-2 from April 25, 2022 to June 8, 2022 in Shanghai Jiao Tong University School of Medicine were selected as the allergic disease group, while 114 cases without underlying diseases and 16 cases with other underlying diseases were selected as control groups diagnosed at the same period. Clinical data including clinical features, laboratory tests, duration of hospitalization, and the time to negative turn of novel coronavirus nucleic acid were collected and analysed. Kruskal-Wallis H test, chi-square test or Fisher exact test were used for comparison among three groups. Results: Among the 43 patients with allergic diseases, 28 were males and 15 were females, with an age of 4.4 (2.1, 8.2) years on admission, including 32 mild cases and 11 common cases. The allergic disease group included 20 cases (46.5%) of atopic dermatitis and eczema, followed by 14 cases (32.6%) of rhinitis, 8 cases (18.6%) of food allergies, 7 cases (16.3%) of asthma, 4 cases (9.3%) of allergic conjunctivitis and 2 cases (4.7%) of drug allergy. Among the 114 cases without underlying diseases, 57 were males and 57 were females, with an age of 2.8 (1.2, 5.6) years on admission, including 93 mild cases and 21 common cases. Among the 16 cases with other underlying diseases, 9 were males and 7 were females, with an age of 3.0 (2.6, 10.8) years on admission, including 13 cases mild and 3 cases common cases. Children with allergic diseases had higher frequency of sore throat and vomiting than those without underlying diseases (10 cases (23.3%) vs.9 cases (7.9%), 14 cases (32.6%) vs. 11 cases (9.6%), χ²=6.93, 12.24, both P<0.05). The lymphocyte count of patients with allergic disease was lower than those without underlying disease (1.1 (0.7,1.7)×10⁹ vs. 1.6 (1.1,2.7)×10⁹/L, H=-28.00,P=0.005). There were no significant differences in age, gender, typing of SARS-CoV-2, the duration of hospitalization, cycle threshold values of SARS-CoV-2 and the time to negative turn of novel coronavirus nucleic acid among the three groups (all P>0.05). Conclusions: Children with allergic diseases may suffer from sore throat and vomiting more frequently when infected with SARS-CoV-2 Omicron variant. The combination of allergic diseases hardly influenced the disease course of SARS-CoV-2 in children.
Male ; Female ; Humans ; Child ; SARS-CoV-2 ; Cross-Sectional Studies ; COVID-19 ; China/epidemiology* ; Food Hypersensitivity ; Pharyngitis

Objective: To investigate the natural history and risk factors for continued allergy in infants with IgE-mediated cow's milk protein allergy (CMPA). Methods: This was a prospective cohort study that included 72 infants under 24 months of age diagnosed with IgE-mediated CMPA in the allergy clinic of the Children's Hospital, Capital Institute of Pediatrics from October 2019 to November 2020. General information, clinical manifestations, serum total IgE, cow's milk specific IgE, and cow's milk protein component specific IgE were collected. Follow-ups were conducted at 24 and 36 months of age, and the patients were divided into the persistent allergy group and the tolerance group based on whether they developed cow's milk tolerance at 36 months of age. Mann-Whitney U test, chi-square test, and binary Logistic regression were used for intergroup comparison and multivariate analysis. Results: Among the 72 CMPA children, there were 42 boys and 30 girls, with an age of 10 (7, 15) months at enrollment. Cow's milk protein tolerance was observed in 32 cases (44%) and 46 cases (64%) at 24 and 36 months of age, respectively. There were 26 cases in the persistent allergy group and 46 cases in the tolerance group. The proportion of respiratory symptoms, history of wheezing, positive specific IgE for α-lactalbumin and the total IgE level in the persistent allergy group were higher than that in the tolerance group (7 cases (27%) vs. 0, 6 cases (23%) vs. 2 cases (4%), 67% (14/21) vs. 26% (10/39), 225 (151, 616) vs. 48 (21, 185) kU/L, χ²=10.82, 4.16, 9.57, Z=4.07, all P<0.05). Multivariate Logistic regression analysis showed that anaphylaxis (OR=21.14, 95%CI 2.55-175.14, P=0.005), a history of allergic rhinitis (OR=5.94, 95%CI 1.54-22.86, P=0.005), elevated milk specific IgE (OR=1.04, 95%CI 1.01-1.08, P=0.024), and positive casein specific IgE (OR=6.64, 95%CI 1.39-31.69, P=0.018) were risk factors for continuous CMPA. Conclusions: Most infants with IgE-mediated CMPA can achieve tolerance within 3 years. Anaphylaxis, a history of allergic rhinitis, elevated milk specific IgE levels, and casein sensitization are risk factors for continuous allergy.
Male ; Animals ; Female ; Cattle ; Infant ; Humans ; Child ; Milk Hypersensitivity/diagnosis* ; Caseins ; Prospective Studies ; Anaphylaxis ; Risk Factors ; Rhinitis, Allergic ; Immunoglobulin E ; Milk Proteins/adverse effects*

Objective: To analyze the clinical characteristics of children with IgE-mediated cow's milk protein allergy (CMPA) and provide a basis for disease management and prevention. Methods: A cross-sectional study was conducted to analyze 142 children aged 0-12 years who were diagnosed with IgE-mediated CMPA in Capital Institute of Pediatrics Affiliated Children's Hospital from 2020 to 2022. There were 79 males (55.6%) and 63 females (44.4%), with an average age of 14 (8, 27) months. 61 cases (43.0%) were in the <1-year-old group, 54 cases (38.0%) in the 1-3-year-old group, and 27 cases (19.0%) in the >3-year-old group. Data on demographic data, clinical manifestations, mean wheel diameter of skin prick test and serum specific IgE level were collected. The serum cow's milk protein sIgE and component sIgE were measured by ImmunoCAP fully automated system of fluorescence enzyme-linked immunosorbent assay, and statistically analyzed using chi-square test, nonparametric tests, correlation. Results: Cutaneous symptoms were the first and most frequent in 142 children (97.9%, 139/142 cases), followed by digestive (29.6%, 42/142 cases) and respiratory symptoms (27.5%, 39/142 cases).The proportion of children with respiratory symptoms after consuming cow's milk was significantly higher in the>3 years age group than those in the infant and toddler groups(66.7% vs 19.7%,χ²=18.396,P<0.01;66.7% vs 16.7%,χ²=20.250,P<0.01), and the symptoms involving ≥3 systems were also significantly higher than those in the other two groups(37.0% vs 13.1%,χ²=6.597,P<0.05;37.0% vs 7.4%,χ²=12.120,P<0.01). The average cow's milk SPT diameter and serum sIgE levels in the>3 years age group were significantly higher than those in the infant and toddler groups (Z=-4.682, P<0.01; Z=-3.498, P<0.01); (Z=-4.463, P<0.01; Z=-6.463, P<0.01). The most common cow's milk component protein were β-lactoglobulin(65.1%,56/86 cases) and casein (57.0%, 49/86 cases). Multiple-sensitization rate of the patients were 54.9%. Egg white (43.7%, 62/142 cases) was the most common co-sensitization food allergen while mold (12.7%, 18/142 cases) and weed pollen (12.7%, 18/142 cases) were the main co-sensitization aeroallergens. The proportion of multiple-sensitization to aeroallergens in the children group was the highest (51.9%, 14/27 cases), followed by the toddler group (29.6%, 16/54 cases), and the infant group was the least (3.3%, 2/61 cases). There was a significant difference among these three groups (χ²=7.476, P<0.05). Conclusion: Skin and mucosal symptoms are the most common in CMPA patients. The proportion of respiratory symptoms and multisystem involvement increased with age as well as the wheal diameter in skin test and serum sIgE level elevated. CMPA patients older than 3 years had the highest proportion of aeroallergen sensitization and airway allergic diseases.
Male ; Animals ; Cattle ; Female ; Child ; Humans ; Milk Hypersensitivity/diagnosis* ; Cross-Sectional Studies ; Food Hypersensitivity ; Allergens ; Immunoglobulin E