Treatment Difficulties in Wheat Oral Immunotherapy and the Predictive Value of Wheat-Specific IgE.

BACKGROUND: Factors associated with wheat oral immunotherapy (OIT) difficulties in patients with IgE-mediated wheat allergy have not been well studied. OBJECTIVE: We aimed to assess factors associated with difficulties in wheat OIT. METHODS: We retrospectively collected data from children under 18 years of age with history of IgE-mediated wheat allergy who underwent wheat OIT. The initial specific IgE (sIgE) of wheat and omega-5-gliadin, wheat skin prick test (SPT) sizes, eliciting doses, and adverse reactions during the OIT were evaluated. RESULTS: A total of 81 children were enrolled, with a mean age of 7.0 ± 2.7 years at the initiation of wheat OIT. The median follow-up duration was 2 years (IQR 1.2 -3.0 years). Difficulties in wheat OIT included patients who experienced frequent reactions (at least grade 2 or exercise-induced reactions) or deviated from the up-dosing protocol, which we defined as 'Complicated cases.' Twenty-six patients (32.1%) were complicated cases. Initial wheat-sIgEs were significantly higher in complicated cases than in noncomplicated cases (median of 192.3 kUA/L (IQR 30.4-590.0) vs 6.9 kUA/L (IQR 1.9-100.0) (p = 0.001)). Initial omega-5-gliadin-sIgEs in the complicated group were also significantly higher, with a median of 15.0 kUA/L (IQR 6.3-69.8) vs 1.6 kUA/L (IQR 0.2-11.4) (p < 0.001). The risk factors for complicated cases include higher omega-5-gliadin-sIgEs and anaphylaxis during the oral food challenge test (aOR 1.035 and 5.684, respectively). CONCLUSION: The initial wheat and omega-5-gliadin-sIgEs were significant risk factors for complicated OIT patients and could be used to monitor these patients carefully during the OIT period.

Factor associated with food allergy among preschool children with atopic dermatitis, and resolution of atopic dermatitis.

BACKGROUND: Food allergy (FA) has been reported in one-third of children with moderate-to-severe atopic dermatitis (AD). OBJECTIVE: To identify factor associated with food allergy among preschool children with AD, and to compare AD resolution between preschool children with and without FA. METHODS: A cross-sectional study using database registry and questionnaire interview was conducted at Siriraj Hospital(Bangkok, Thailand) during 2022, and physician-diagnosed AD children aged ≤ 6 years were enrolled. RESULTS: A total of 110 children (60.9% male, median age: 2.3 years) were included. Of those, 53 and 57 children had AD with and without FA, respectively. Very early-onset AD (≤ 3 months) and moderate-to-severe AD at onset were reported in 43.9% and 26.3% of AD without FA, and in 35.8% and 45.3% of AD with FA, respectively. The most commonly reported FAs were hen's egg, cow's milk, and wheat. Moderate-to-severe AD at onset was found significant associated with FA (aOR: 2.50; p = 0.037). Thirty-one (28.2%) patients experienced completed resolution of AD by 5 years of age. Of those, 19 had AD without FA, and 12 had AD with FA (p = 0.213). The median age at AD resolution was 18 months and 22.5 months in the without and with FA groups, respectively. AD with FA showed a strong trend toward a significantly longer duration to achieving AD resolution after adjusting for onset and severity of AD (aHR: 0.46, p = 0.050). CONCLUSION: Preschool AD children with FA were found to have significantly greater AD severity at AD onset and a longer duration to AD resolution compared to AD children without FA.

Is a Prolonged Drug Provocation Test Better Than a Single-Day Drug Provocation Test? A Systematic Review and Meta-Analysis.

BACKGROUND: There is currently no standardized duration of drug provocation test (DPT) for confirming/delabeling beta-lactam hypersensitivity reaction (BL-HSR). OBJECTIVES: This meta-analysis and systematic review aimed to investigate the added diagnostic value of extended-day over single-day DPT for confirming/delabeling BL-HSR in adults and children. METHODS: The MEDLINE, EMBASE, Web of Science, and CINAHL online databases were searched from inception to March 15, 2023, for studies that performed extended-day DPT to confirm/delabel BL-HSR. Risk difference and risk ratio were used to compare the proportions of patients with confirmed BL-HSR by single-day or extended-day DPT. RESULTS: A total of 10,371 DPTs from 42 studies were included. Extended-day DPTs ranged from 2 to 7 days, or as long as index reactions were reported (maximum 10 days). The overall prevalence of confirmed BL-HSR was 6.96% (3.31% during the first-day DPT, and 3.65% during extended-day DPT). Approximately half of the positive reactions during extended-day DPT occurred during the second/third day. The increased detected pool prevalence of confirmed BL-HSR yielded by extended-day DPT was 0.03 (95% CI, 0.02%-0.04%; I2 = 57.69%; P < .001), and the risk ratio of positive reactions between extended-day and single-day DPT was 1.94 (95% CI, 1.62-2.33; I2 = 36.26%; P < .001). The risk difference increased per 1% increase in prevalence of BL-HSR by 0.6% (95% CI, 0.4%-0.7%; P < .001). Twenty-three severe reactions occurred during DPT, and only 2 severe reactions (0.02%) occurred during extended-day DPT. An additional 28 extended-day DPTs were needed to identify 1 mild reaction. CONCLUSIONS: The increased prevalence of confirmed BL-HSR observed during extended-day DPT could be attributed to the first-day DPT. As a result, our findings do not conclusively support the use of extended-day DPT over single-day DPT. Further studies, incorporating a washout period, are required to comprehensively compare these 2 approaches.

Food-Dependent Exercise-Induced Anaphylaxis: A Distinct Form of Food Allergy-An Updated Review of Diagnostic Approaches and Treatments.

Food-dependent exercise-induced allergic reactions (FDEIA) represent a distinct clinical phenomenon where symptoms arise during exercise following the consumption of specific trigger foods, with the most severe manifestation being anaphylaxis-a condition distinct from typical exercise-induced or food-induced anaphylaxis. In FDEIA, patients can either exercise or tolerate specific foods separately without experiencing any allergic reactions. Diagnosis relies on patient history and provocation testing, requiring rigorous implementation within a supervised hospital environment. Positive symptoms and clinical signs during testing confirm FDEIA, while negative outcomes do not preclude its presence. Exercise stands as the primary trigger, followed by nonsteroidal anti-inflammatory drugs (NSAIDs) and alcohol. The utilization of various protocols for food cofactor challenges to confirm FDEIA yields differing diagnostic outcomes. We highlight the updated concept of food cofactor challenges, incorporating protocols reported in the literature, and summarize current recommendations and comprehensive management approaches for FDEIA patients.

Identifying the stability of a new wheat gliadin extract by protein analysis, skin tests and cell degranulation assay.

BACKGROUND: The commercial wheat extract for skin prick test (SPT) provides less sensitivity to predict wheat allergy, compared to in-house gliadin extracts. SPT is a preferred method to study extract stability as it is the aim of developing extract. The role of cell degranulation assay, a functional assay with the same mechanism as SPT, is not widely used to determine extract stability. OBJECTIVE: To study the stability of in-house gliadin extracts stored at different periods, by using protein analysis, SPT and degranulation assay of humanized rat basophilic-leukemia (RBL-SX38) cells. METHODS: Patients with a history of wheat allergy and positive SPT to wheat, were recruited. The gliadin extracts stored for 1, 6, 9, and 12 months at 2-8°C were used in SDS-PAGE, SPT and cell degranulation assay. The cell degranulation was determined by ß-hexosaminidase release. AR patients. RESULTS: Forty children were recruited. The gliadin extract stored for 9 and 12 months provided lighter protein bands than 1 and 6 months. However, the wheal diameters from SPT using extracts stored at different periods, were not significantly different (p = 0.09). There were also no significant differences of the ß-hexosaminidase released using 0.1 and 1 µg/mL of gliadin extracts stored at different periods (p > 0.05). The 10 µg/mL of gliadin extracts stored at longer periods, significantly stimulated higher ß-hexosaminidase release (p = 0.01). The extracts were sterile at all storage times. CONCLUSIONS: To determine the stability of in-house gliadin extracts, SPT or cell degranulation assay provided additional information to SDS-PAGE. The extracts were stable for up to 12 months.

Patient-rated angioedema severity using a novel photo-aid for predicting non-mast cell mediator-induced angioedema diagnosis.

Background: Patients with non-mast cell mediator-induced angioedema (NM-AE) usually experience a diagnostic delay. Therefore, a clinical tool for predicting NM-AE diagnosis is essential. Objective: To identify clinical predictors related to a confirmed diagnosis of NM-AE. Methods: Participants with a history of recurrent AE with unknown causes were enrolled. They were classified into mast cell mediator-induced AE (M-AE) and NM-AE according to the response to anti-mast cell mediator therapy. All participants were asked to rate their worst AE ever experienced (% Photomax) from 0 to 100% using a novel photo aid. Clinical characteristics were recorded and analyzed by univariable and multivariable analysis. Results: Thirty-five participants were included, 25 with NM-AE and 10 with M-AE. AE located at extremities, face, and genitalia and positive family history were significantly associated with NM-AE. The AE severity in the NM-AE group was significantly higher than in the M-AE group, with the mean % Photomax of 82.4 ± 20.3 vs 47.5 ± 25.6 (p < 0.001), respectively. Univariable analysis showed that the % Photomax (every 10% increase), feet AE and hands AE were predictive of being NM-AE with the area under the receiver operating characteristic curve (AuROC) of 0.87 (95% CI 0.75, 0.99), 0.85 (95% CI 0.72, 0.98), and 0.84 (0.69, 0.99), respectively. Multivariable analysis showed that the combination of hands AE and % Photomax enhanced diagnostic accuracy (AuROC 0.94, 95% CI 0.86, 1.0) and constituted the prototype formula for calculating the diagnostic probability. Conclusion: Patient-rated angioedema severity using a novel photo aid combined with hands AE had a high probability of diagnosing NM-AE.

The natural history of childhood-onset nonallergic rhinitis; a long-term follow-up study.

BACKGROUND: Non-allergic rhinitis (NAR) is characterized by symptoms of nasal inflammation without allergic sensitization. The long-term outcome of NAR in children is poorly defined. OBJECTIVE: To determine the natural history of childhood-onset NAR and the development of allergic rhinitis (AR) in these children. METHODS: NAR patients who were followed for more than 10 years were evaluated at 3-5 years (E2) and 9-12 years (E3) after the first evaluation (E1). Nasal symptoms, disease severity, comorbidities, medication used, and aeroallergen sensitization were assessed. RESULTS: Eighty-two NAR patients (58.5% male) completed all 3 evaluations. The age at onset was 2.0 (range 2.0-4.0) years. The follow-up period was 13.6 (range 12.3-14.3) years. At E2, 37.8% of patients developed AR. At E3, the patients were classified into four groups based on results of skin prick tests in E2 and E3 (group I: NAR→NAR→NAR, 39.0%, group II: NAR→NAR→AR, 23.2%, group III: NAR→AR→NAR, 12.2% and group IV: NAR→AR→AR, 25.6%). The most common aeroallergen sensitization was house dust mite. The family history of atopy, asthma and allergic rhinitis were higher in group III and IV than other groups (p < 0.05). The atopic dermatitis, obstructive sleep apnea and adenotonsillar hypertrophy at E1 and E2 were predominantly found in group IV (p < 0.05). At E2, group III and IV patients had higher proportion of exposure to house dust, animal dander and smoking compared to other groups (p < 0.05). The overall remission rate was 14.6%. CONCLUSIONS: Children with NAR should be reevaluated periodically to determine aeroallergen sensitization for the appropriate diagnosis and management.

Children with wheat anaphylaxis and with low wheat specific IgE have a different IgE immunoblot pattern than those with high wheat specific IgE.

BACKGROUND: Children with wheat anaphylaxis can present with a wide range of wheat-specific IgE (sIgE). OBJECTIVE: To identify differences in clinical features and predominant wheat allergens sensitized by these patients. METHODS: Children with history of wheat anaphylaxis were recruited. Skin prick test (SPT) to wheat, sIgE to wheat, omega-5 gliadin (ω5G), lipid transfer protein (LTP) were investigated. Profiles of IgE-bound wheat allergens were studied to identify predominant wheat allergens. RESULTS: Twenty-nine children (17 males) aged 1-18 years were enrolled. Sixteen patients (55.2%) had wheat-sIgE > 100 kUA/L (WAhi) and 13 patients (44.8%) had wheat-sIgE < 34 kUA/L (WAlo). The median of peak wheat-sIgE in WAhi and WAlo were 340.5 kUA/L (IQR 184.3, 564.5) and 12.2 kUA/L (IQR 1.4, 41.3), respectively. Oral food challenge test (OFC) was carried out in 12 of 13 patients in the WAlo group, all of which had positive results. Eight of these 12 patients developed anaphylaxis during OFC despite having wheat-sIgE less than 10 kUA/L. There were no differences in clinical characteristics and atopic history between WAhi vs. WAlo. Medium to low molecular weight gliadin (< 40 kDa) and glutenin (< 60 kDa) were commonly recognized by patients with WAhi. IgE immunoblot pattern among the WAlo group was more widely dispersed than those with WAhi. CONCLUSIONS: Wheat anaphylaxis can occur in patients with low wheat-sIgE. Predominant wheat allergens recognized by patients with WAlo were different than those with WAhi. Such difference could be responsible for anaphylaxis at even low levels of wheat-sIgE.

A potential role of gliadin extract skin prick test in IgE-mediated wheat allergy.

BACKGROUND: Wheat extracts containing both water/salt and alcohol soluble proteins may increase extract's accuracy for diagnosing IgE-mediated wheat allergy. OBJECTIVE: This study aimed to determine the performance of new invented in-house prepared wheat extracts for skin prick test (SPT). METHODS: Children aged 1-18 years with history of immediate wheat allergy were recruited. Four in-house prepared wheat extracts (wheat-Coca-10%EtOH, and 3 new invented extracts, wheat-salt, gliadin, and glutenin) and a commercial wheat extract were used for SPT. Serum specific IgE (sIgE) to wheat and omega-5 (ω-5) gliadin were also determined. Oral food challenge (OFC) with wheat flours was performed in all patients except those with history of wheat-induced anaphylaxis or with recent symptoms within the past 6 months. RESULTS: Thirty-one children were recruited. Of those, 14 were excluded from OFC (12 with history of anaphylaxis and 2 with recent symptom). OFC was positive in 8 of 17 children. Of the 5 extracts and sIgE to wheat and ω-5 gliadin, gliadin extract provided the best SPT performance with 84.2% sensitivity, 88.9% specificity, 94.1% positive predictive value (PPV), 72.7% negative predictive value (NPV), 7.59 positive likelihood ratio (LR), 0.18 negative LR, and 85.7% accuracy. CONCLUSIONS: Compared to other in-house and commercial wheat extracts and sIgE to wheat and ω-5 gliadin, SPT with an in-house gliadin extract yielded the highest performance for the diagnosis IgE-mediated wheat allergy.

Validation and Reliability of the Thai version of the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF).

BACKGROUND: Food allergy has an impact on the quality of life of both patients and caregivers. It is, therefore, important to have a native language survey to evaluate health-related quality of life (HRQL) among food allergic children. OBJECTIVE: To translate the Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) to Thai language, and to validate this tool in Thai parents with food allergic children. METHODS: The FAQLQ-PF was translated into Thai language according to WHO guideline. The FAQLQ-PF Thai version was then administered to the parents of food allergic Thai children aged 0-12 years. The FAQLQ-PF Thai version was then readministered to those same parents 10-14 days after they first completed this assessment tool. Internal consistency by Cronbach's α and test-retest reliability by intraclass correlation coefficient (ICC) were assessed. The discriminant validity of the questionnaire was also evaluated. RESULTS: Ninety parents of participants answered the FAQLQ-PF Thai version. Of those, 9 parents (10%) incompletely answered the first questionnaire. The FAQLQ-PF Thai version showed good internal consistency (Cronbach's α ≥ 0.799), but the test-retest reliability was only fair (ICC > 0.6). Factors that adversely affected the quality of life of Thai children with food allergy included age, presence of anaphylaxis, frequency of reactions, and the number of implicated foods. Patients with wheat allergy were negatively impacted in all domains of quality of life, whereas those with shellfish allergy had only emotional impact. CONCLUSIONS: The FAQLQ-PF Thai version is a reliable and valid tool for assessing HRQL in Thai children with food allergy.

Is mold sensitization associated with severe asthma exacerbation in children?

BACKGROUND: Mold sensitization has been reported as a factor associated with severe asthma exacerbation (SAE). OBJECTIVE: To identify the factors associated with SAE in asthmatic children, particularly mold sensitization. METHODS: The asthmatic children recruited into this case-control study were classified into an SAE and an outpatient (OPD) group, based on their histories of asthma exacerbation with hospitalization in the preceding year. A skin prick test to common aeroallergens was performed. Possible SAE risk factors were analyzed. RESULTS: A total of 102 patients were enrolled. The 51 patients in the SAE group were significantly younger than the 51 in the OPD group (mean ages of 6.8 ± 3.3 vs 8.7 ±3.2 years, p = 0.005). Higher proportions of patients with partly controlled or uncontrolled asthma were found in the SAE group (41.2% vs 17.6%, p = 0.009). The incidences of a paternal history of atopy, an emergency department visit, and a history of systemic corticosteroid administration in the preceding year were significantly higher for the SAE group (35.3% vs 15.7%, p = 0.023; 100% vs 43.5%, p < 0.001; and 100% vs 31.4%, p < 0.001; respectively). The multivariate logistic regression analysis showed that risk factors for SAE were Alternaria sensitization (adjusted odds ratio [AOR] 3.00; 95% CI 1.09-8.3; p = 0.033), patients who were younger than 6 years (AOR 3.28; 95% CI 1.17-9.18; p = 0.024), and a paternal history of atopy (AOR 2.94; 95% CI 1.05-8.25; p = 0.040). CONCLUSIONS: Alternaria sensitization, an age younger than 6 years, and a paternal history of atopy were associated with SAE in asthmatic children.

The Safety of the Direct Drug Provocation Test in Beta-Lactam Hypersensitivity in Children: A Systematic Review and Meta-Analysis.

BACKGROUND: Direct drug provocation test (DPT) without prior skin testing (ST) has been investigated in children suspected of being at risk for beta-lactam (BL) hypersensitivity reaction (HSR). However, no systematic review and meta-analysis has investigated the efficacy and safety of direct DPT for BL-HSR in children. OBJECTIVE: To investigate the prevalence of BL-HSR by direct DPT and the safety of direct DPT in children. METHODS: We searched MEDLINE, EMBASE, Web of Science, and CINAHL from their inception to July 23, 2022, for studies that performed direct DPT in children with suspected BL-HSR, or for studies that performed DPT in all cases with ST results, but they ignored the ST results. The true prevalence was defined as the proportion of children who experienced an HSR during direct DPT. Safety was determined according to the proportion of children who developed a dangerous reaction following DPT. RESULTS: Twenty-eight studies with 8,334 direct challenges were included. Fifteen studies included patients who presented with either immediate or nonimmediate HSR, and the majority of the index reactions were nonsevere. Amoxicillin/amoxicillin-clavulanic acid was the most commonly used during the DPT. The pooled prevalence of confirmed BL-HSR was 5.23% (95% CI 4.17-6.39; I2 = 72%). Immediate and nonimmediate HSR were reported in 0.8% (95% CI 0.43-1.25; I2 = 55.1%) and 3.69% (95% CI 2.66-4.87; I2 = 79.77%), respectively. Severe reactions were found in 3 cases with the frequency of 0.036% (95% CI 0.012-0.112; I2 = 0%). CONCLUSIONS: The prevalence of BL-HSR by direct DPT was 5.23%, and the frequency of severe reactions from direct DPT was very low (0.036%). Our findings support direct DPT as a safe and effective delabeling tool in children with suspected nonsevere BL-HSR.

Hypersensitivity reactions to iodinated radiocontrast media: Cluster analysis reveals distinct clinical phenotypes.

Background: Drug hypersensitivity reaction (DHR) to iodinated radiocontrast media (iRCM) is reported in 1%-3% of injections. Risk assessment of patients with suspicion of DHR to iRCM relies solely on clinical phenotyping and drug allergy workup. Using a novel unsupervised TwoStep cluster analysis, we aimed to identify prototypic patterns within a large cohort of patients evaluated for a potential iRCM DHR. Methods: A retrospective study was conducted using data from the Drug Allergy and Hypersensitivity Database of the Allergy Unit, University Hospital of Montpellier, Montpellier, France. All referred patients during February 2001 to December 2019 with suspicion of iRCM DHR with either confirmed positive or confirmed negative skin tests were included in the analysis. Results: A total of 1439 patients were evaluated. The chronology of the index reaction was immediate and nonimmediate in 77.1% and 22.4%, respectively. Cluster analysis categorized the total study population in 5 clusters. Cluster 1 compiled all nonimmediate and cluster 2-5 almost all immediate reactors. Cluster 1 and 2 had recent reactions (<1 y) with mostly known iRCMs and the highest iRCM allergy prevalence (16-17%). In the other clusters, more remote reactions, unknown iRCMs and a lower allergy prevalence (3-8%) was observed. Chronology and semiology of the index reaction were the factors most strongly differentiated among clusters. History of anaphylactic shock and chronology of immediate hypersensitivity reactions were shown to be independent predictors of allergy with adjusted OR (aOR) of 4.68 (95%CI: 3.01-7.27, p < 0.001) and 2.51 (95%CI: 1.67-3.78, p < 0.001), respectively. Conclusions: Unsupervised cluster analysis identified 5 prototypic patterns within patients with a suspected DHR to iRCMs. Well-phenotyped patients cluster together in 2 groups in which the prevalence of allergy is approximately 1 in 6. However, this value decreases for patients with reactions dating back to more than a decade.

Diagnostic performance of serial serum total tryptase measurement to differentiate positive from negative allergy testing among patients with suspected perioperative hypersensitivity.

BACKGROUND: Serum total tryptase has been shown to increase during acute allergic reactions (acute tryptase, TA ); however, few studies have investigated the values of TA or a combination of TA and baseline tryptase (TB ) to discriminate positive from negative testing in perioperative hypersensitivity reaction (POH) allergy work-up. The aim of this study was to determine the diagnostic performance of TA in order to differentiate positive from negative allergy testing suspected POH and analyse the diagnostic performance of serial tryptase levels using several formulas. METHODS: All patients from the University hospital of Montpellier and Strasbourg, France, who presented with suspected POH and underwent complete drug allergy work-up between March 2011 and December 2019 with available TA and TB were included. Four formulas, including a change in TA  > 11 (F1), or >2 + 1.2 × TB (F2), or >3 + TB (F3), or >120%TB (F4), were applied. RESULTS: One hundred and sixty-two patients were included, and 131 of them (80.8%) had Grade III or IV reactions. Ninety patients had positive allergy testing. The optimal cut-off value of TA to distinguish positive from negative allergy testing patients was 9.8 µg/L with an AUC of 0.817 (95% CI: 0.752-0.882, p < .001). The 93% PPV threshold for TA was 33 µg/L (95.8% specificity). Paired tryptase levels according to formulas F2 and F3 yielded the highest Youden index (0.54 and 0.53, respectively). CONCLUSION: The optimal cut-off point for TA for distinguishing positive from negative allergy testing suspected POH was 9.8 µg/L. TA value of 33 µg/L was required to achieve >90% PPV.

Food sensitization and food allergy in allergic Thai patients from a tertiary care center in Thailand.

BACKGROUND: A skin prick test (SPT) and food challenge test (OFC) are useful in identification of food sensitization and food allergy. OBJECTIVE: To evaluate food allergen sensitization by SPT and food allergy by OFC in allergic Thai patients. METHODS: SPTs for common food allergens were performed on allergic patients at Siriraj Hospital, Bangkok, Thailand, from 2011 to 2015. An OFC was performed in positive food SPT patients with informed consent. RESULTS: SPTs to food were positive in 539 (20%) out of 2,678 allergic patients (73.8% were < 10 years old). Crab was the most common sensitized food in each year of the study period. In patients aged < 1 year, the most common sensitized foods were egg white (23.8%) and wheat (22.2%), while shrimp was for patients aged > 10 years (25%). A positive OFC was found in 29 (26.1%) out of the 111 OFCs performed (9.1% in patients with asthma, 28.6% in allergic rhinitis and 26.3% in food allergy). Positive OFCs were found for 60% of the crab, 35.7% of the egg yolk, and 31% of the cow's milk OFCs. Compared to OFC, SPT showed high specificity (71%-100%) but low sensitivity (0%-40%). The percentage of sensitization to egg white, egg yolk, wheat, soy, and peanut significantly increased (p < 0.05) from 2011 to 2015. CONCLUSION: The sensitization to egg white, egg yolk, wheat, soy, and peanut significantly increased and crab was the most common sensitized food. Food allergy in patients with allergic rhinitis was as common as in patients diagnosed food allergy.

Characterization of children with IgE-mediated wheat allergy and risk factors that predict wheat anaphylaxis.

BACKGROUND: The number of children presenting with IgE-mediated wheat reactions to academic medical centers in Thailand continues to increase. OBJECTIVE: Improved knowledge about the clinical characteristic of wheat allergy is urgently needed to better understand the risk factors and to improve proper treatment in this patient population. METHODS: A cross-sectional study using questionnaire review of children who presented with IgE-mediated wheat allergy during 2001 to 2015 was performed. Patients were divided into the wheat anaphylaxis (WA) or the only skin symptoms (SO) group. RESULTS: One hundred children were enrolled. Fifty-one and 49 patients were allocated to the WA and SO group, respectively. The median age was 40.5 months (range: 6-200), and the median age of onset was 7 months (range: 3-96). The vast majrity (90%) developed their first reaction after their first ingestion of wheat. Atopic dermatitis (AD) was found to be the only significant difference between groups and found more commonly in SO than in WA (59.2% vs. 35.3%, p = 0.02). Median mean wheal diameter (MWD) of skin prick test (SPT) and median sIgE level to wheat were higher in WA than in SO (8 vs. 3 mm, p < 0.001; and, 33.3 vs. 3.6 kUA/l, p < 0.001). CONCLUSIONS: Children with wheat allergy presented very early in life. AD was found in approximately half of the patients, and more commonly in SO. Median MWD of SPT and sIgE level to wheat were significantly higher in WA. These data will aid in further planning for a larger survey and intervention study in wheat allergy.

Prevalence of rat and mouse sensitization in Asian patients with respiratory allergy.

BACKGROUND: Skin prick test (SPT) is useful in identifying rat and mouse sensitization. OBJECTIVE: To determine the prevalence of rat and mouse sensitization by using local and commercial allergen extracts. METHODS: Patients with allergic rhinitis or asthma were recruited. SPT of local and commercial rat and mouse allergen extracts were performed. The level of rat and mouse specific IgE (sIgE) was quantified in all patients with positive SPT and randomized patients with negative SPT. RESULTS: Two hundred and thirty patients, 108 male (47%) and median age 14 years (3.2-63.5 years), were enrolled. Rat sensitization by SPT was 11.7% and mouse sensitization was 17.8%. SPT result to local rat and commercial rat allergen extracts were moderately correlated (rs = 0.51, p < 0.001), while SPT result to local mouse and commercial mouse allergen extracts showed low correlation (rs = 0.38, p < 0.001). The concordance of SPT results between local rat and commercial rat allergen extracts was 90.4%. Concordance between the local mouse and commercial mouse allergen extracts was 85.2%. When compared with rat and mouse sIgE, the concordance of local rat, commercial rat and commercial mouse allergen extract were > 80% while that of local mouse was 54.4%. No adverse effect was observed in SPT with any allergen or extract. CONCLUSIONS: The prevalence of rat and mouse sensitization was low compared to the study in USA. SPT with local rat and mouse allergen extract was safe and showed good concordance with the SPT result of commercial allergen extracts and rat and mouse sIgE levels.

Prick and intradermal skin tests in patients with severe hymenoptera sting allergy using commercial versus in-house allergen extracts.

BACKGROUND: Fire ant, honey bee, and wasp allergen extracts are useful in the diagnosis and treatment of severe Hymenoptera allergic patients. OBJECTIVE: To evaluate the result of skin prick test (SPT) and intradermal test (ID) compared between local and commercial insect allergen extracts in patients with severe Hymenoptera sting allergy. METHODS: SPT and ID using local and commercial insect allergen extracts were performed. Specific IgE (sIgE) to honey bee, wasp, and fire ant; component-resolved diagnosis (CRD); (rApi m1, rApi m2, rApi m3, rApi m5, rApi m10, rVes v5, rPol d5, and rVes v1); and, cross-reactive carbohydrate determinant (CCD) were performed. RESULTS: Twenty-seven patients were included. Twenty-five had anaphylaxis, and 2 had severe systemic skin reaction. Positive skin test (SPT and/or ID) result from local and commercial allergen extracts was 74% vs. 67% for fire ant, 48% vs. 59% for honey bee, and 52% vs. 74% for yellowjacket. Local and commercial allergen extracts showed substantial agreement for fire ant (k = 0.647, p = 0.001) and honey bee (k = 0.632, p = 0.001), and moderate agreement for wasp (k = 0.547, p = 0.001). When compared with sIgE subtracted with CCD and/or CRD, skin test results of local fire ant allergen extract showed higher sensitivity (87% vs. 67%), specificity (42% vs. 33%), and accuracy (67% vs. 52%) than commercial extract. Commercial honey bee and wasp showed higher sensitivity (62% vs. 50%, 85% vs. 65%) and accuracy (63% vs. 52%, 78% vs. 70%), respectively. CONCLUSIONS: SPT and ID with local or commercial insect venoms could help in confirming and/or identifying the causative insects.