[Characterization of asthma phenotypes in children of the tropics]

OBJECTIVE

Determine the main asthma phenotypes in a population of asthmatic children in Cartagena, Colombia.

METHODS

107 children (7 to 17 years old) with a previous diagnosis of asthma were recruited. Biomarkers of T2 inflammation were evaluated by measuring FeNO, eosinophil count in peripheral blood by hemocytometry, and determination of specific IgE to mite allergens by ELISA. The study was approved by the ethics committee of the University of Cartagena (SGR, Grant BPIN2020000100405).

RESULTS

The average age of patients was 10,9 years. 19,6% of the children did not show elevation of any of the T2 inflammation biomarkers evaluated (FeNO<20ppb, eos<300/ul, negative specific IgE), so they were considered patients with non-allergic asthma (non-T2). 71,9% of all patients were sensitized to at least one allergen, this phenotype was considered allergic asthma. 30,8% of the patients presented the three elevated biomarkers (FeNO>20ppb + eos >300/ul + positive specific IgE), this phenotype was classified as high T2 allergic asthma. A moderate correlation (Spearman rho=0,44, p<0,0001) was found between FeNO values and eosinophil counts.

CONCLUSION

In this study, the following phenotypes were found: allergic asthma, high T2 asthma, and non-allergic asthma. Most patients presented a type 2 inflammatory phenotype with allergic sensitization. In addition to the measurement of specific IgE, the use of FeNO and eosinophil count in peripheral blood help to accurately determine those patients with high T2 asthma phenotypes.

Establishment of a homogeneous chemiluminescence immunoassay for cat dander sIgE antibody detection

BACKGROUND

In vitro specific IgE (sIgE) testing has become an important tool for the diagnosis of IgE-mediated allergic diseases. Current methods used to detect allergen sIgE are time consuming and/or expensive. Therefore, a new method was developed for rapid quantitative detection of cat dander-sIgE antibody based on homogeneous chemiluminescence immunoassay.

METHODS

Selection of chemibeads with different chemical groups, and the best Light-initiated chemiluminescence assay (LiCA) analytical mode for cat dander-sIgE detection. To validate and eliminate the interference of IgE on the detection of cat dander-sIgE, concentration of biotinylated anti-human IgE antibody was optimized. For quantification of cat dander-sIgE, a calibration curve was established, and the performance of the assay was evaluated according to clinical guidelines.

RESULTS

Indirect LiCA is the best mode of analysis and biotinylated anti-human IgE antibody at a dilution ratio of 1:250 minimizes IgE interference. The coefficient of variation of the developed LiCA was 1.49% to 4.66%, with an intermediate precision of 6.90% to 8.21%. The LoB, LoD, and LoQ of the assay were 0.023 kUA/L, 0.056 kUA/L and 0.185 kUA/L. The coefficient of correlation (r) between LiCA and ImmounoCAP was 0.9478.

CONCLUSIONS

A cat dander-sIgE quantitation assay based on homogeneous chemiluminescence immunoassay was established, which could be a new reliable analytical tool for the determination of cat dander-sIgE.

Allergen-specific IgE in the tear fluid of Chinese patients with common allergic conjunctivitis in autumn and winter

PURPOSE

In this study, we determined the positive rates of allergen-specific immunoglobulin E (IgE) in the tear fluid of Chinese patients with common allergic conjunctivitis (AC) in autumn and winter, compared systemic and ocular allergen tests, and explored the correlation between the numbers and categories of allergens and clinical AC features.

METHODS

This cross-sectional study recruited 44 patients with AC (86 eyes). Specific IgEs for allergens common in China (house dust mite, cat/dog dander, mugwort/ragweed pollen, cottonwood/willow/elm pollen, milk, egg whites, soybeans) were measured in collected tears using kits for allergen-specific IgE antibodies. AC signs and symptoms were graded according to severity.

RESULTS

Specific IgE in tears was positive in 87.2% of eyes. House dust mite was the most common allergen (86.0%), followed by cat (24.4%) and dog (7.0%) dander; tree and grass pollen accounted for only 4.7% and 2.3%, respectively. Food allergens were not detected. The positive rates of the systemic allergen tests were lower than in tear fluid tests in both eyes, especially for house dust mites (P = 0.000). In patients with more allergens, itching was more severe (P = 0.035), while conjunctival hyperemia was milder (P = 0.002).

CONCLUSION

In autumn and winter, the most common AC allergen in Chinese patients was house dust mites. Compared with systemic allergen tests, measuring specific IgE in tears may be a non-invasive method to diagnose and evaluate AC severity, which may be more suitable to reflect the local conditions of ocular surface inflammation due to its high positive rate and convenience.

Revealing clinically relevant specific IgE sensitization patterns in Hymenoptera venom allergy with dimension reduction and clustering

Background

Immunoglobulin E (IgE) blood tests are used to detect sensitizations and potential allergies. Recent studies suggest that specific IgE sensitization patterns due to molecular interactions affect an individual's risk of developing allergic symptoms.

Objective

The aim of this study was to reveal specific IgE sensitization patterns and investigate their clinical implications in Hymenoptera venom allergy.

Methods

In this cross-sectional study, 257 hunters or fishers with self-filled surveys on previous Hymenoptera stings were analyzed. Blood samples were taken to determine Hymenoptera IgE sensitization levels. Using dimensionality reduction and clustering, specific IgE for 10 Hymenoptera venom allergens were evaluated for clinical relevance.

Results

Three clusters were unmasked using novel dimensionality reduction and clustering methods solely based on specific IgE levels to Hymenoptera venom allergens. These clusters show different characteristics regarding previous systemic reactions to Hymenoptera stings.

Conclusion

Our study was able to unmask non-linear sensitization patterns for specific IgE tests in Hymenoptera venom allergy. We were able to derive risk clusters for anaphylactic reactions following hymenoptera stings and pinpoint relevant allergens (rApi m 10, rVes v 1, whole bee, and wasp venom) for clustering.

History and Utility of Specific IgE Cutoff Levels: What is the Relevance for Allergy Diagnosis?

Allergy is defined clinically, by symptoms on allergen exposure. A patient is considered sensitized when allergen-specific IgE (sIgE) antibody can be detected in serum or plasma or a skin test result is positive, even if no clinical reaction has been experienced. Sensitization should be regarded as a requisite and risk factor for allergy but is not synonymous with an allergy diagnosis. To provide a correct allergy diagnosis, test results regarding allergen-sIgE must always be considered in view of the patient's case history and clinical observations. Correct assessment of a patient's sensitization to specific allergens relies on the use of accurate and quantitative methods for detection of sIgE antibodies. The evolution of sIgE immunoassays toward higher analytical performance and the use of different cutoff levels in the interpretation of test results sometimes cause confusion. Earlier versions of sIgE assays offered a limit of quantitation of 0.35 kilounits of sIgE per liter (kUA/L), which also became an established cutoff level for a positive test result in the clinical use of the assays. Current sIgE assays are capable of reliably measuring sIgE levels as low as 0.1 kUA/L and can thereby demonstrate sensitization in cases in which previous assays could not. When the outcome of sIgE test results is evaluated, it is critically important to distinguish between the analytical data as such and their clinical interpretation. Even though sIgE may be present in the absence of symptoms of allergy, available information suggests that sIgE concentrations between 0.1 kUA/L and 0.35 kUA/L may be clinically relevant in some individuals, not least among children, although this should be further evaluated for various allergies. Moreover, it is becoming widely adopted that nondichotomous interpretation of sIgE levels may offer a diagnostic benefit compared with using a predefined cutoff level.

Exercise-Induced Allergic Reactions in Children Desensitized to Hen's Eggs and Cow's Milk by Oral Immunotherapy

BACKGROUND

Exercise-induced allergic reactions on desensitization (EIARDs) after successful in-hospital rush oral immunotherapy (OIT) for wheat allergy have been reported. However, the incidence rates of EIARDs after rush OIT for egg allergy and milk allergy have not been determined.

OBJECTIVE

To determine the frequency of EIARDs and risk factors associated with rush OIT for egg and milk allergy.

METHODS

This retrospective chart review, conducted in January 2020, enrolled 64 and 43 patients who underwent rush OIT for egg and milk allergy, respectively (in 2010 to 2014). In particular, 48 and 32 desensitized patients underwent exercise-provocation tests (Ex-P) after allergen administration (4,400 mg boiled egg white and 6,600 mg cow's milk protein, respectively). The EIARDs were determined by Ex-P or a suspicious event even after passing the Ex-P. Specific IgE levels to egg white, cow's milk, ovomucoid, casein, α-lactalbumin, and β-lactoglobulin were analyzed using ImmunoCAP.

RESULTS

At least one episode of EIARD was observed in 10 and 17 patients with egg and milk allergy (21% and 53%), respectively, which persisted for more than 5 years in one patient with egg allergy (2.1%) and 11 patients with milk allergy (34.4%) as of January 2020. We could not find background differences between the EIARD-positive and EIARD-negative groups, except that the egg white-specific IgE/total IgE ratio before rush OIT was significantly higher in patients with egg allergy with EIARD than in those without it.

CONCLUSIONS

Exercise-induced allergic reactions on desensitization were more frequent and common in patients with milk allergy. Moreover, EIARDs to milk allergy were more likely to persist than those to egg allergy.

Safety of Oral Food Challenge for Individuals with Low Egg White and Ovomucoid-Specific IgE Antibodies

INTRODUCTION

During an oral food challenge (OFC), there is a risk of adverse reactions, including anaphylaxis. Therefore, the physician should carefully conduct the OFC. This study aimed to evaluate the OFC results in individuals with low levels of egg white (EW)- and ovomucoid (OVM)-specific immunoglobulin E (sIgE) and the safety of a hen's egg (HE) OFC in these individuals.

METHODS

A total of 2,058 individuals with low EW- or OVM-sIgE underwent HE-OFC at two institutions in Kumamoto prefecture, located in the western area of Japan, between January 1, 2017, and December 31, 2021, within 1 year of recorded sIgE measurements. The ImmunoCAP systems were used to measure sIgEs. The HE-OFC test was performed according to the 2017 Food Allergy Guidelines in an open and unblinded method.

RESULTS

Five hundred and one individuals (24.3%) had low EW-sIgE levels (class 2 or lower), and 926 (45.0%) had low OVM-sIgE levels (class 2 or lower). Individuals with low EW-sIgE had lower total IgE and OVM-sIgE than did those with high EW-sIgE (greater than class 2). Those with low OVM-sIgE had lower total IgE and EW-sIgE than did those with high OVM-sIgE (greater than class 2). Among the individuals with low EW-sIgE, 86.4% (433/501 cases) passed the OFC without symptoms. Among the individuals with low OVF-sIgE, 82.6% (765/926 cases) passed the OFC without symptoms.

CONCLUSION

More than 80% of individuals with suspected IgE-dependent HE allergy and low levels of EW- or OVM-specific IgE were able to consume at least a small amount of HE. As the OFC results are independent of the loading dose in cases with low EW- or OVM-sIgE, a medium-dose HE-OFC may be performed safely in individuals with no history of anaphylaxis.

Prevalence of allergen sensitization among children with allergic rhinitis in Changzhou, China: a retrospective observational study

OBJECTIVE

To determine the prevalence of sensitivity to common inhaled and food allergens among children with allergic rhinitis (AR) in Changzhou in eastern China and provide a basis for epidemiological research of pediatric allergic rhinitis and allergen avoidance in this region.

METHODS

This was a retrospective observational study, a total of 1248 children with AR were enrolled at the Third People's Hospital of Changzhou between January 2018 and December 2019. The serum-specific immunoglobulin E (sIgE) to 19 kinds of inhaled and food allergens and serum total IgE were detected with the AllergyScreen test (Mediwiss Analytic GmbH, Moers, Germany). All participants had a positive reaction to at least one allergen in the test (the sIgE concentration ≥ 0.35 IU/ml).

RESULTS

Among the patients, 818 (65.54%) were male and 430 (34.46%) were female, with 81 (6.50%) aged 1-3 year, 501 (40.14%) aged 4-7 year, and 666 (53.36%) aged 8-14 year. The positivity rate of inhaled allergens was 80.05% (n = 999), while the positivity rate of food allergens was 66.19% (n = 826). 828 patients (66.35%) were sensitized to multiple allergens. The most common inhaled allergens were Dermatophagoides pteronyssinus (65.38%), mold mix (25.56%), house dust (20.67%), and dog hair dander (13.94%), and the most common food allergens were cow's milk (30.31%), cashew nut (27.9%), egg (22.68%), and beef (12.98%). With an increase in age, the inhaled allergen positivity rate showed a significant increase (P < 0.01), while the food allergen positivity rate decreased significantly (P < 0.01). There were significant age differences in total IgE levels (P < 0.01) and the total IgE level was highest in the group aged 8-14 year.

CONCLUSIONS

Dermatophagoides pteronyssinus was the most common sensitizing allergen in pediatric patients with AR in Changzhou. Several other inhaled and food allergens were also common. We observed that multiple allergenic factors play an important role in the occurrence and development of AR.

Comparative analysis of serum total IgE levels and specific IgE levels in children aged 6 to 9 years with tic disorder and normal children

OBJECTIVE

The study was to investigate serum total IgE levels and the distribution of specific IgE types in children aged 6-9 years with tic disorder, in order to provide knowledge for diagnosis and treatment of children with tic disorder.

METHODS

Total serum IgE levels were detected by enzyme-linked immunosorbent assay (ELISA). Specific IgE levels in 72 children with tic disorder and normal 31 children were detected by EUROblot, respectively.

RESULTS

The total serum IgE level of children with tic disorder aged 6-9 years was significantly higher than those of children in control group. Specific IgE distribution in tic disorder group was observed increased mainly including inhaled mugwort, dust mite combination 1 (house dust mite/dust mite), mold combination (penicillium point/mycobacteria/Aspergillus fumigatus/streptomyces), cockroaches in Germany respectively, and also food freshwater fish combination 1 (salmon/sea bass/carp), marine fish combination 1 (cod/lobster/scallop), egg white, and crab, while elevated specific IgE of normal children group was mainly food-based (egg white, milk, and soybean). The significant different specific IgE between two groups was dust mite combination 1 (house dust mite/dust mite) (P < 0.05).

CONCLUSION

The total serum IgE level of children with tic disorder aged 6-9 years was significantly increased, which may be related to the disease. Specific IgE in children with tic disorder was mainly inhalation allergens, especially dust mite combination 1 (house dust mite/dust mite), which should be avoided in clinical diagnosis and daily life.

Skin prick tests are not useful for the qualification for venom immunotherapy in children

Background

The basis for qualification for venom immunotherapy (VIT) is the fulfilment of both the clinical and immunological criteria. Diagnostic tests that confirm the immunological criterion of an IgE-mediated sensitization include skin prick tests (SPT), intradermal tests (IDT), and serum specific IgE (sIgE) for the culprit venom.

Objective

This study aimed to assess the usefulness of SPT as the immunological marker in the diagnosis of insect venom sensitization in children with history of systemic reaction (SR) to insect sting evaluated by means of I-IV-grades Mueller's scale. There are no such studies in children.

Methods

This cross-sectional study sample consisted of 416 children aged 3-18 years (mean age 10.6 ± 3.8), 76% males, all with the history of a systemic reaction (SR) after a Hymenoptera sting (48% of grade III/IV according to Mueller scale), diagnosed between 1999 and 2019 in the tertiary referral centre. The standard diagnostic tests were used. Specificity, sensitivity, and positive and negative predictive values were computed to assess the diagnostic properties of the clinical tests to distinguish between mild and severe SR. To assess the relative value of an individual test in predicting the qualification to VIT we incorporated the Shapley value (SV).

Results

Positive SPT results were found in up to no more than 3% of children; among them less than 1% had only positive SPT and were negative for sIgE and IDT. Approximately 85% of the children had detectable venom sIgE, followed by positive IDT (75%). Almost 70% of children had positive both sIgE and IDT results. In children with grade III/IV reaction, about 80% of children had positive results of both of these tests. sIgE and IDT had sensitivity >0.80, whereas SPT had high specificity (>0.97) in differentiating between mild and severe SR. Relative value of diagnostic tests in predicting qualification to VIT varied between venoms. Bee venom IDT had higher SV (0.052) than sIgE (0.041). In contrast, wasp venom sIgE had higher SV (0.075) than IDT (0.035).

Conclusion

SPTs are not an useful immunological marker of venom sensitization in children, and eliminating SPT does not result in a loss of diagnostic accuracy. Limiting diagnostics to venom sIgE and IDT would shorten the procedure and reduce costs. Future studies are needed to determine if venom sIgE as the first line diagnostic test, with IDT added only if the venom sIgE is undetectable, is an optimal diagnostic process.

Prevalence of common sensitizing aeroallergens in patients with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD), a skin disease burden worldwide, is a complex, multifactorial, chronic inflammatory disease. Prevalence of AD is increasing in developing countries and identifying the causative allergens is a major challenge. Aeroallergens are shown to aggravate atopic dermatitis.

PURPOSE

Explore the prevalence of aeroallergens sensitization in patients with AD and its possible relation with AD severity.

METHODS

Cross-sectional study of 132 patients diagnosed to have atopic dermatitis. Atopy was detected by serum specific IgE to a panel of the most encountered aeroallergens.

RESULTS

From the 132 patients, elevated specific IgE was detected in 72.7 % from which 59.1 % were mild and 86.4 % are moderate/severe as well as 15.9 % are mono-sensitized and 54.5 % are poly-sensitized with poly-sensitization being more in severe cases compared to mild cases (68.2 % vs 4.5 %). Regarding specific IgE to different aeroallergens, the most prevalent were Dermatophagoides pteronyssinus (50 %), followed by Dermatophagoides farinae (34.1 %), Birch pollen (20.5 %), cat epithelium (18.2 %) Regweed (15.9 %), and Cockroach (9.1 %). However, moderate to severe cases were more sensitized to candida (p = 0.012), mix grass pollen (p = 0.002), ragweed (0.00), mite (p = 0.037) and cat epithelium (p = 0.007).

CONCLUSION

Dermatophagoides pteronyssinus, Dermatophagoides farinae, Birch pollen, cat epithelium Regweed and Cockroach are the most frequent sensitizing aeroallergens in atopic dermatitis.

Allergenic and Mas-Related G Protein-Coupled Receptor X2-Activating Properties of Drugs: Resolving the Two

Since the seminal description implicating occupation of the Mas-related G protein-coupled receptor X2 (MRGPRX2) in mast cell (MC) degranulation by drugs, many investigations have been undertaken into this potential new endotype of immediate drug hypersensitivity reaction. However, current evidence for this mechanism predominantly comes from (mutant) animal models or in vitro studies, and irrefutable clinical evidence in humans is still missing. Moreover, translation of these preclinical findings into clinical relevance in humans is difficult and should be critically interpreted. Starting from our clinical priorities and experience with flow-assisted functional analyses of basophils and cultured human MCs, the objectives of this rostrum are to identify some of these difficulties, emphasize the obstacles that might hamper translation from preclinical observations into the clinics, and highlight differences between IgE- and MRPGRX2-mediated reactions. Inevitably, as with any subject still beset by many questions, alternative interpretations, hypotheses, or explanations expressed here may not find universal acceptance. Nevertheless, we believe that for the time being, many questions remain unanswered. Finally, a theoretical mechanistic algorithm is proposed that might advance discrimination between MC degranulation from MRGPRX2 activation and cross-linking of membrane-bound drug-reactive IgE antibodies.

Intraoperative chlorhexidine-induced anaphylaxis suggesting an immunoglobulin-E-dependent mechanism indicated by basophil activation tests: two case reports

BACKGROUND

Although chlorhexidine allergy has been shown to be mediated by immunoglobulin (Ig) E, few reports investigated the mechanism of chlorhexidine-induced anaphylaxis using basophil activation tests (BATs).

CASE PRESENTATION

A 79-year-old man underwent cholecystectomy under general anesthesia. Anaphylaxis was diagnosed based on the clinical symptoms and high serum tryptase and histamine levels. Skin tests showed positive results only for chlorhexidine. Subsequently, BATs demonstrated that the causative agent was likely chlorhexidine. The inhibitory effect of wortmannin, an inhibitor of phosphoinositide 3-kinase, on basophil activation suggested an IgE-dependent mechanism underlying chlorhexidine-induced anaphylaxis. An 89-year-old man underwent inguinal hernioplasty under general anesthesia. Anaphylaxis was diagnosed based on the clinical symptoms and high serum tryptase and histamine levels. Skin tests and BATs with wortmannin were performed, showing similar results to case 1.

CONCLUSIONS

BATs suggested an IgE-dependent mechanism for chlorhexidine-induced anaphylaxis and might be useful for investigating the mechanisms underlying drug-induced anaphylaxis.

The Indirect Basophil Activation Test Is a Safe, Reliable, and Accessible Tool to Diagnose a Peanut Allergy in Children

BACKGROUND

The gold standard for the diagnosis of a peanut allergy is an oral food challenge (OFC), but it is a time-consuming, patient-unfriendly, and expensive test. The in vitro direct basophil activation test (BAT) for peanuts was shown to be a promising diagnostic tool for replacing the OFC.

OBJECTIVE

To determine the diagnostic accuracy of the indirect (passive) BAT. Compared with the direct BAT, the timing of the indirect BAT is more flexible, and the problem of nonresponding basophils (unresponsive to IgE receptor-mediated signaling) is circumvented.

METHODS

In 74 children, suspected of peanut allergy and eligible for an OFC, indirect BAT results for peanut extract, Ara h2, and Ara h6 were compared with the results of a double-blind placebo-controlled food challenge. The reactivity and sensitivity of the basophils in the BAT were correlated to both the allergy status and the threshold dose in the OFC.

RESULTS

The combined basophil reactivity for Ara h2 and Ara h6 showed the highest accuracy (94%) for the diagnosis of a peanut allergy, with positive and negative predictive values of 96% and 89%, respectively. The sensitivity of the basophils for Ara h2 significantly discriminates between patients who tolerated up to 0.4 g of peanut protein in the OFC and those who did not.

CONCLUSIONS

Because the indirect BAT showed a high diagnostic accuracy for peanut allergy, it is a promising alternative to the classical direct BAT and could lead to a reduction in OFC use.

Molecular Profile of Specific IgE to Allergenic Components in Allergic Adults Using Allergen Nano-Bead Array

BACKGROUND

An increasing interest in the field of molecular diagnosis of allergy has been developed in recent years and it goes to be as the routine in-vitro protocol in allergy diagnosis. Friendly Allergen Nano-bead Array (FABER) is a new multiplex assay for the evaluation of specific IgE against 244 allergens including whole extracts and allergenic molecules. The research intended to assess the pattern of IgE sensitization to allergenic components of allergens in allergic adults using FABER 244.

METHODS

Sixty patients with allergic diseases entered this cross-sectional study. Specific IgE to 122 whole allergens extracts and 122 allergenic components was assessed using an allergen nano-bead array (FABER) for all patients. This test includes inhalant and food allergens.

RESULTS

Thirty-seven patients were male (61.7%). The mean (SD) age of patients was 30.73(±6.87) years. As the allergen nano-bead array results showed, Lolium perenne (63.3%), Phleum pretense (60%), and Platanus acerifolia (51.7%) were considered as the most common IgE-sensitizations to the aeroallergen extracts. Moreover, Lol p 1, Phl p 1.0102, and Cup a 1 were found as the most frequent allergenic components in our allergic patients. Among protein families, CCD bearing proteins, expansin, cysteine protease, and profilin families illustrated the highest allergic sensitization.

CONCLUSIONS

The results of the present study demonstrated that despite the higher prevalence of sensitization to Salsola kali (47.2%) using extract-based assays in the previous phase of this research, allergenic components of grasses (Lol p 1, Phl p 1.0102), Cup a 1 as well as Sal k1 as the major components of Cupressuss arizonica and Salsola kali showed the higher sensitization, respectively in adults' allergic patients using FABER test.

Development of a light-initiated chemiluminescence assay for the quantitative detection of cow's milk allergen-specific IgE

BACKGROUND

Cow's milk allergy is a common food allergy in children. Clinically, cow's milk-specific IgE (CM-sIgE) antibody test is often used to diagnose milk allergy. An inexpensive light-initiated chemiluminescence assay (LICA), with fast detection speed and small sample volume demand, has application prospects in the field of quantitative detection of CM-sIgE.

METHODS

Chemibeads coated with five major milk allergens, serum samples, biotinylated anti-human IgE antibodies, and streptavidin-coated sensibeads constitute a system to establish a LICA method for the quantitative detection of CM-sIgE. A series of experiments were performed to optimize its reaction conditions and evaluated its performance.

RESULTS

The optimal conditions for LICA were 10:4 mass ratio of chemibeads to milk allergen, 20 μg/mL chemibeads, 1.0 μg/mL biotinylated anti-human IgE antibodies and a 1/10 dilution of serum for 30-min incubation. The limit of Quantitation (LoQ) was 0.22 kU_A/L. For repeatability, the CV ranged from 3.71% to 8.11%. For intermediate precision, the CV ranged from 4.08% to 14.71%. It was linear within 0.20-18.20 kU_A/L. This method did not interfere with common interfering substances and total IgE in serum, and there was no obvious cross-reaction with milk-specific IgG and non-milk-specific IgE.

CONCLUSION

We have established a method to quantitatively detect CM-sIgE based on light-initiated chemiluminescence assay, which has good analytical performance and could meet the needs of clinical laboratories.

Elevated Cow's Milk-Specific IgE Levels Prior to Oral Immunotherapy Decrease the Likelihood of Reaching the Maintenance Dose

BACKGROUND

Food desensitization via oral immunotherapy (OIT) is gaining acceptance in clinical practice. Owing to adverse reactions, the duration of the buildup phase until a maintenance dose is achieved may be prolonged, and in a minority of cases, OIT is stopped.

OBJECTIVE

We aimed to assess factors associated with the probability of reaching the maintenance dose in cow's milk (CM) OIT.

METHODS

We collected data from patients undergoing CM OIT at the Montreal Children's Hospital, BC Children's Hospital, and Hospital for Sick Children. We compared univariable and multivariable Cox regressions to evaluate sociodemographic factors, comorbidities, clinical characteristics, and biomarkers at study entry associated with the likelihood of reaching a maintenance dose of 200 mL of CM.

RESULTS

Among 69 children who reached 4 mL of milk, the median age was 12 years (interquartile range, 9-15 years); 59% were male. Median duration of buildup phase from 4 to 200 mL was 24.0 weeks (interquartile range, 17.7-33.4 weeks). After adjusting for age and sex, higher baseline levels of specific IgE antibodies for α-lactalbumin (hazard ratio [HR] = 0.80; 95% confidence interval [CI], 0.67-0.95), β-lactoglobulin (HR = 0.86; 95% CI, 0.76-0.98), casein (HR = 0.82; 95% CI, 0.72-0.94), and total CM (HR = 0.79; 95% CI, 0.65-0.97) were associated with a decreased probability of reaching maintenance. In addition, for every 10-mL increase in CM tolerated at entry challenge, the probability of reaching maintenance increased by 10%.

CONCLUSIONS

The data suggest that higher levels of CM-specific IgE decreased the likelihood of reaching maintenance, whereas an increased cumulative CM dose at entry challenge increased the likelihood. Assessing these factors before therapy may assist in predicting the success of CM OIT.

Combining Allergen Components Improves the Accuracy of Peanut Allergy Diagnosis

BACKGROUND

IgE to peanut often occurs in the absence of peanut allergy. Detection of allergen component specific IgE (sIgE) has improved diagnosis and birthed molecular allergen component arrays, in which sensitization to multiple allergen components can be measured simultaneously.

OBJECTIVE

To improve the diagnostic utility of serology for peanut allergy, by mapping interactions of sIgE to multiple components and IgE functional characteristics.

METHODS

A cohort of 100 children was studied, with a 60-children cohort employed for external validation. Levels of total IgE, sIgE to peanut, and peanut components were measured using singleplex ImmunoCAP and multiplex immuno solid-phase allergen chip (ISAC). Peanut IgE specific activity, avidity, and diversity were determined. Diagnostic modeling was performed using a Bayesian hierarchical model.

RESULTS

Sensitization to the 112 allergens on ISAC (model 1) demonstrated the highest accuracy to diagnose peanut allergy (area under the curve [AUC] = 0.92). Sensitization to peanut components on ISAC (model 2) reported an AUC of 0.86 and on singleplex (model 3) an AUC of 0.92, which was greater than that of Ara h 2 sIgE alone (AUC = 0.90). Functional characteristics of peanut sIgE (model 4) reported an AUC of 0.89, which was greater than that of peanut sIgE (AUC = 0.75). Model 3 offered the highest predictive value and the second highest overall diagnostic accuracy.

CONCLUSIONS

sIgE to a combination of allergen components (Ara h 1, 2, 3, and 6) is highly predictive of peanut allergy and superior to individual markers. Combining the functional characteristics of IgE was superior to peanut sIgE levels alone. These models can be applied in real time during clinical consultations using online calculators.

Detection of Wheat Lipid Transfer Protein (Tri a 14) Sensitization: Comparison between Currently Available Diagnostic Tools

BACKGROUND

Wheat lipid transfer protein (LTP; Tri a 14) and ω5-gliadin have been described as major allergens in wheat allergy (WA) and relevant in wheat-induced anaphylaxis, frequently associated with cofactors.

OBJECTIVE

The objective of this study was to compare tools currently available in routine diagnosis to detect Tri a 14 sensitization, its clinical relevance, and cosensitization to ω5-gliadin and other LTPs.

METHODS

One hundred eighteen adults sensitized to rTri a 14 by ImmunoCAP® (cutoff ≥0.1 kUA/L) identified among 210 LTP allergic patients were included. We evaluated (1) wheat skin prick test (SPT), (2) specific IgE (sIgE) to wheat, rTri a 14, rTri a 19, peach, apple, walnut, hazelnut, and peanut LTPs using ImmunoCAP® and microarray ImmunoCAP®ISAC (cutoff ≥0.3I SU), and (3) wheat-related symptoms.

RESULTS

Wheat SPT and sIgE were positive in 31% and 85% of subjects, respectively. rTri a 14 by microarray was detected in 25%. Eight percent showed cosensitization to ω5-gliadin. Thirty percent referred symptoms (gastrointestinal [13%], urticaria [11%], and anaphylaxis [8%]). Cofactors (45%) were significantly associated with systemic reactions.

CONCLUSION

WA due to Tri a 14 is frequently related with systemic reactions and because are frequently related to cofactors, the culprit may not be suspected. Together with the poor performance to identify Tri a 14 sensitization of the current routine diagnostic tools based on the analysis of whole wheat extract, such as wheat SPT or sIgE, there is a high risk that WA may be overlooked. Thus, when WA is suspected, sIgE Tri a 14 assessment is recommended, together with wheat and ω5-gliadin, preferably in the singleplex format, and carefully evaluated considering ≥0.1 kUA/L as a cutoff.

Distinct differences in analytical performance of two commercially available assays for specific IgE to egg white and house dust mite allergens

Background

Measurements of allergen-specific IgE antibodies with different manufacturers’ assays show modest or poor agreement. This study compares analytical performance of specific IgE tests for whole allergen extracts and individual allergen components of two assay systems, IMMULITE and ImmunoCAP, using human sera as well as monoclonal antibodies.

Methods

Comparisons were performed for specific IgE to house dust mite (HDM, n = 44), egg white (EW, n = 36) and the allergen components rDer p 1, rDer p 2, nGal d 1, nGal d 2 and nGal d 4 in human sera and with monoclonal mouse/human chimeric IgE antibodies specific for the same allergen components. Competitive interference with IgE measurement was investigated using allergen-specific monoclonal IgG and IgG4 antibodies.

Results

Measurements of IgE to HDM and EW in serial dilutions of human sera revealed weaker dilution linearity with IMMULITE than with ImmunoCAP. Analysis of five different monoclonal IgE antibodies with total and specific IgE assays, expected to return similar levels, gave an average specific/total IgE ratio of 0.96 (range 0.71–1.14) with ImmunoCAP and 1.89 (range 0.76–2.85) with IMMULITE, indicating overestimation of specific IgE by IMMULITE. With the EW IgE tests of both assay systems, measurements of a chimeric anti-Gal d 2 IgE antibody were unaffected by a competing mouse IgG antibody. While the same was true for measurement of a chimeric anti-Der p 1 IgE antibody using the HDM test in ImmunoCAP, a suppression of measured concentrations by up to 42% was observed in IMMULITE. Similarly, measurement of HDM-specific IgE in human sera by ImmunoCAP was unaffected by a competing monoclonal anti-Der p 2 IgG4 antibody while IMMULITE displayed a reduction of HDM-specific IgE values by up to 30%.

Conclusions

In this evaluation of analytical performance of two widely used assay systems, ImmunoCAP showed higher accuracy in quantitation of specific IgE and greater resistance against competing allergen-specific non-IgE antibodies which may arise through natural or dietary exposure, or as a result of allergen immunotherapy treatment.

A light-initiated chemiluminescent assay for the detection of children's milk protein-specific IgE with excellent ability to avoid interference of specific IgG

The detection of allergen-specific IgE is of value for the diagnosis of children's milk allergy. However, its accuracy will interfere with the presence of high levels of specific IgG in the serum of children with milk allergy. To solve this problem, we established a light-initiated chemiluminescent assay (LICA) based on nanomicrospheres, which neutralized the interference of specific IgG by increasing the amount of antigen coated on the microspheres. The ability of this method to resist IgG interference was confirmed by adding extra specific IgG to the serum of allergic patients. Finally, the positive rate of allergen-specific IgE was increased to 85%, which was better than the indirect ELISA (70%), indicating that this method has certain advantages for the detection of specific IgE in children with milk allergy.

Detection of drug-specific immunoglobulin E (IgE) and acute mediator release for the diagnosis of immediate drug hypersensitivity reactions

The diagnosis of a drug hypersensitivity reaction (DHR) is complex. The first step after taking the clinical history is to look for a sensitization to confirm or exclude the diagnosis and to identify the culprit drug. Skin tests are the primary means of detecting sensitization in DHR, but are associated with a risk for a severe reaction and may be contraindicated. In vitro tests offer the potential to support or confirm a diagnosis of DHR and influence medical decision making. For immediate-type DHR, a few validated assays for measurement of specific IgE (sIgE) are commercially available to a limited number of drugs. In addition, several home-made sIgE radioimmunoassays have been used in other studies. The sensitivity of the sIgE assay is drug-dependant and generally low (0-85%) for betalactams and reported heterogeneous for other drugs ranging from 26% for chlorhexidine and 44% for suxamethonium to 92% for chlorhexidine. However, as all these studies included patients, in whom DHR was confirmed only by skin tests and not by provocation, the results have to be interpreted carefully and may be unreliable. Determination of mediators during an acute phase of a reaction may indirectly support the diagnosis of a DHR by demonstrating mast cell and basophil mediator release. Negative in vitro tests do not exclude a DHR or imputability of a drug, but a positive result may support causality and eliminate the necessity for a drug provocation test. Unfortunately, evidence is limited with a lack of well-controlled studies in larger numbers of well-phenotyped patients, which results in susceptibility for bias and a need for future multicenter studies.

Nationwide pharmacovigilance data for cetuximab-induced anaphylaxis and predictive model validation using prospective specific IgE detection

Background

Cetuximab (chimeric monoclonal antibody to human epidermal growth factor receptor) is used to treat colorectal and head and neck cancers. Due to cross-reactivity with galactose-α-1,3-galactose (alpha-gal), it can induce hypersensitivity even at first administration. We aimed to determine the incidence and clinical manifestation of cetuximab-induced anaphylaxis, and to establish a means of predicting its incidence in patients ahead of treatment.

Methods

Nationwide and single-center pharmacovigilance data from 2010 to 2017 were collected from the Korea Institute of Drug Safety-Korea Adverse Event Reporting System and Severance Regional Pharmacovigilance Center. Patients scheduled for cetuximab administration were enrolled prospectively. A skin prick test was carried out and serum IgE specific to cetuximab and cross-reactive allergens were measured. Reactions were monitored after cetuximab infusion.

Results

Over 8 years, there were 23 reports of anaphylaxis nationwide. In a single-center study, incidence of cetuximab-induced anaphylaxis was 1.1%. Most anaphylaxis occurred at first injection (93.3%), even under pretreatment with anti-allergic drugs. Four of 64 patients (6.3%) experienced severe anaphylaxis. The median cetuximab-specific IgE titer was 6.9 kU_A/L in patients experiencing anaphylaxis and 0 kU_A/L in those who did not (P < 0.001). The results of alpha-gal, beef sIgE, and cetuximab skin prick testing were similar to those of cetuximab sIgE. Patients who did not experience hypersensitivity were negative in all 4 allergy tests. Its positive and negative predictive values were 100%.

Conclusions

Specific IgE detection of cetuximab or alpha-gal can accurately predict cetuximab-induced anaphylaxis prior to first administration.

Fermentation of Gluten by Lactococcus lactis LLGKC18 Reduces its Antigenicity and Allergenicity

Wheat is a worldwide staple food, yet some people suffer from strong immunological reactions after ingesting wheat-based products. Lactic acid bacteria (LAB) constitute a promising approach to reduce wheat allergenicity because of their proteolytic system. In this study, 172 LAB strains were screened for their proteolytic activity on gluten proteins and α-amylase inhibitors (ATIs) by SDS-PAGE and RP-HPLC. Gliadins, glutenins, and ATI antigenicity and allergenicity were assessed by Western blot/Dot blot and by degranulation assay using RBL-SX38 cells. The screening resulted in selecting 9 high gluten proteolytic strains belonging to two species: Enterococcus faecalis and Lactococcus lactis. Proteomic analysis showed that one of selected strains, Lc. lactis LLGKC18, caused degradation of the main gluten allergenic proteins. A significant decrease of the gliadins, glutenins, and ATI antigenicity was observed after fermentation of gluten by Lc. lactis LLGKC18, regardless the antibody used in the tests. Also, the allergenicity as measured by the RBL-SX38 cell degranulation test was significantly reduced. These results indicate that Lc. lactis LLGKC18 gluten fermentation can be deeply explored for its capability to hydrolyze the epitopes responsible for wheat allergy.

Improving Diagnostic Accuracy in Food Allergy

The diagnosis of food allergy can have a major impact on the lives of patients and families, imposing dietary restrictions and limitations on social activities. On the other hand, misdiagnosis can place the patient at risk of a potentially severe allergic reaction. Therefore, an accurate diagnosis of food allergy is of utmost importance. The diagnosis of food allergy is often established by the combination of the clinical history and allergen-specific IgE; however, without a clear history of an allergic reaction, the interpretation of IgE sensitization tests can be difficult. There are also rare cases of clinical food allergy in the absence of IgE sensitization. For that reason, testing for suspected food allergy ideally requires access to oral food challenges (OFCs), which are currently the gold standard tests to diagnose food allergy. As OFCs are time consuming and involve the risk of acute allergic reactions of unpredictable severity, the question remains: how can we improve the accuracy of diagnosis before referring the patient for an OFC? Herein, we review the predictive value of different tests used to support the diagnosis of food allergy, discuss implications for therapy and prognosis, and propose a diagnostic approach to be applied in clinical practice.

Allergen detection and analysis in Eastern Taiwan area

Objective:

Environmental factors, eating habits, and different ages might affect the profiles of allergy sensitization. The purpose of this study was to survey the different profiles of allergen sensitization in different ages in eastern Taiwan.

Materials and Methods:

We analyzed the allergic patients who had allergen sensitization examinations by the Phadiatop (atopy screen; IBT Laboratories, Lenexa, KS, USA) and the Pharmacia CAP System method at Haulien Tzu Chi Hospital from January 2010 to December 2015. Results were compared in different ages.

Results:

A total of 15,455 patients were analyzed. The food and aeroallergen screen sensitization rate of children was significantly higher than that of adults (44.0% vs. 9.9% and 61.9% vs. 52.2% P < 0.05). Children had statistically significantly higher cow milk allergen-specific sensitization rate than that of adults (32.9% vs. 5.8% P < 0.05). The higher sensitization of shrimp occurred in adults than children. (33.6% vs. 24.8% P < 0.05).

Conclusion:

Our data demonstrate that children have higher cow milk allergy sensitization and adults have higher sensitization of shrimp.

Drug-specific history, skin and in vitro tests can reduce the need for drug provocation tests in betalactam-hypersensitivity

BACKGROUND

Many patients report questionable drug hypersensitivity reactions (DHR) to betalactam antibiotics. A workup is required for objectivation. Direct drug provocation tests (DPTs) omitting a prior allergy workup are increasingly recommended as the primary diagnostic approach. However, apart from the risk of severe side effects, DPTs often are a scarce resource in overloaded healthcare-systems. We investigated how many cases can be solved by drug-specific history, drug-specific IgE, and skin tests obviating the need for DPT.

METHODS

We conducted a chart review in a retrospective cohort of 932 patients in an allergy outpatient centre from 2016 to 2017. Patients had been submitted to drug-specific history and specific IgE-, skin prick-, intradermal- and patch-tests with early and late readings with a series of penicillins and cephalosporins but DPTs were no option.

RESULTS

Overall, positive in vitro and/or skin tests were found in 96/932 (10.3%) patients. Drug-specific IgE was detected in 40/932 (4.3%) patients, 61/787 (7.8%) patients had positive skin tests. In vitro tests to Pencillin V showed the highest rate of positivity 24/479 (5.0%) and early readings of ampicillin the highest amongst the skin tests (3/49, 6.1%). Immediate skin tests were more often positive than delayed ones (75:45). The combination of all parameters including drug-specific history solved 346/932 (37.1%) cases while 586/932 (62.9%) remained unresolved. Self-reported DHR could be less often confirmed in females and young children (p < 0.05).

CONCLUSIONS

Testing with betalactams applying simple, cheap, and safe skin and blood tests can solve a third of DHR-cases on a high throughput scale.

The role of house dust mite immunotherapy in Indonesian children with chronic rhinosinusitis allergy: A randomized control trial

Background

Chronic rhinosinusitis allergy (CRA) is a disease that is commonly found in children and is mostly caused by allergy to house dust mites (HDM). The use of HDM immunotherapy can be considered in children with allergies.

Objectives

Analyzing the impact of mite immunotherapy on disease burden in Indonesian children with CRA.

Methods

A randomized control trial study was conducted to participants in 2 groups, namely the immunotherapy group (n = 25) and the non-immunotherapy group (n = 25). Participants were given HDM immunotherapy for 14 weeks, which was given once per week. Participants during therapy were evaluated for rhinosinusitis symptoms and measured their immunity status (specific IgE), sleep quality (SDSC), quality of life (SN5), and family coping (F-COPES) pre-post therapy. Statistical analysis used in this study included paired t-test, Wilcoxon test, independent t-test, or Mann Whitney test with p < 0.05.

Results

The value of specific IgE in the immunotherapy group was 4.12 ± 7.75 kU/l (pre-test) and 1.52 ± 2.42 kU/l (post-test; p < 0.001), while in the non-immunotherapy group was 1.47 ± 3.28 kU/l (pre-test) and 1.18 ± 2.81 kU/l (post-test; p = 0.317). The SDSC value in the immunotherapy group was 42.16 ± 2.75 (pre-test) and 30.32 ± 3.22 (post-test; p < 0.001), while in the non-immunotherapy group was 41.92 ± 2.75 (pre-test) and 41.84 ± 2.87 (post-test; p = 0.987). The F-COPES value in the immunotherapy group was 101.56 ± 5.78 (pre-test) and 105.20 ± 4.31 (post-test; p = 0.015), while in the non-immunotherapy group was 100.36 ± 9.63 (pre-test) and 99.96 ± 9.98 (post-test; p = 0.224). The SN-5 value in the immunotherapy group was 30.04 ± 2.78 (pre-test) and 11.00 ± 2.33 (post-test; p < 0.001), while in the non-immunotherapy group was 30.04 ± 2.78 (pre-test) and 30.04 ± 2.78 (post-test; p = 0.767). There was a significant comparison between the immunotherapy group and the non-immunotherapy group on the specific IgE (p = 0.013), SDSC (p < 0.001), and SN-5 (p < 0.001) values. Meanwhile, there was no significant difference in the F-COPES value (p = 0.129).

Conclusions

The administration of HDM immunotherapy can improve the participant's immunity, quality of life, and sleep disorder.

High level of IgE in acute low-tone sensorineural hearing loss: A predictor for recurrence and Meniere Disease transformation

BACKGROUND

Autoimmunity may play an important role in sudden onset sensorineural hearing loss. However, little is known about the relationship between immunoglobulin E (IgE) and acute low-tone sensorinerual hearing loss (ALHL).

OBJECTIVES

To investigate the relationship between IgE level and endolymphatic hydrops and outcomes of ALHL.

METHODS

A total of 242 subjects with sudden onset hearing loss, including 115 with ALHL and 127 with idiopathic sudden sensorineural hearing loss (ISSHL), were included in this study. Peripheral venous blood samples of 242 subjects were collected for detection. Clinical data, IgE level, and distribution of allergens were compared between the ALHL and ISSHL groups. The ALHL group received an electrocochleogram (ECochG) test and a follow-up in the outpatient unit or by telephone to evaluate outcomes.

RESULTS

Compared to the values in the ISSHL group, a significantly younger onset age (42.30±14.33 years old), higher female onset proportion (72/115, 62.61%), increased total IgE level (median: 66.47, interquartile range: 24.56, 180.96, IU/mL) and specific IgE level (median: 9.42, interquartile range: 1.42, 22.23 IU/mL) were noted in the ALHL group. A clear difference in allergen distribution was noted between the ALHL and ISSHL groups (p=.001). Total IgE and specific IgE levels were factors that contributed to the SP/AP ratio in the electrocochleogram (ECochG) (R²=0.413) in ALHL group. Finally, during the follow-up (17.61±3.46 months) for the ALHL group, 37 subjects recurred, and 17 subjects developed Meniere Disease. In the ROC curve for ALHL recurrence, the area under the curve (AUC) of total IgE was 0.709 and that of specific IgE was 0.679. For MD transformation, the AUC of total IgE was 0.736 and that of specific IgE was 0.716.

CONCLUSIONS

High IgE levels correlated with an enhanced SP/AP ratio in ALHL. High IgE levels could be used as a predictor of ALHL recurrence and MD transformation.

Basophil Activation Test Reduces Oral Food Challenges to Nuts and Sesame

BACKGROUND

Nut allergic patients are often IgE sensitized to other nuts/seeds and need multiple oral food challenges (OFCs) before the safe nuts can be introduced in the diet. However, OFCs are time-consuming and risky procedures.

OBJECTIVE

To assess the utility of the basophil activation test (BAT) to predict the allergic status and reduce the need for an OFC in children with 1 or more nut or seed allergies.

METHODS

Participants in the Pronuts study recruited at the Geneva and the London centers were tested on the BAT to hazelnut, cashew nut, sesame, almond, and peanut, Ara h 1, Ara h 2, Ara h 6, using FlowCAST, a commercially available BAT kit, and flow cytometry.

RESULTS

The BAT to hazelnut, cashew nut, sesame, almond, and peanut discriminated between allergic and nonallergic children, to the respective nut or seed. The optimal allergen concentration and their optimal, positive, and negative cutoffs were identified for the BAT and the other tests, for each nut and seed. Using the BAT as a second step in the diagnostic process, after equivocal skin prick test and IgE to extracts and components, reduced the number of total OFCs by 5% to 15% and positive OFCs by 33% to 75% (except for hazelnut) with 0% false-negatives and a diagnostic accuracy of 96% to 100%.

CONCLUSION

The BAT proved to be a useful diagnostic tool, used in a stepwise approach, to predict the allergic status and reduce the number of OFCs in the Pronuts study participants with at least 1 nut allergy willing to consume selected nuts.

Penicillin and cephalosporin cross-reactivity: role of side chain and synthetic cefadroxil epitopes

BACKGROUND

Analysis of cross-reactivity is necessary for prescribing safe cephalosporins for penicillin allergic patients. Amoxicillin (AX) is the betalactam most often involved in immediate hypersensitivity reactions (IHRs), and cefadroxil (CX) the most likely cephalosporin to cross-react with AX, since they share the same R1 side chain, unlike cefuroxime (CO), with a structurally different R1. We aimed to analyse cross-reactivity with CX and CO in patients with confirmed IHRs to AX, including sIgE recognition to AX, CX, CO, and novel synthetic determinants of CX.

METHODS

Fifty-four patients with confirmed IHRs to AX based on skin test (ST) and/or drug provocation test (DPT) were included. Serum sIgE to AX and benzylpenicillin was determined by Radioallergosorbent test (RAST). Two potential determinants of CX, involving intact or modified R1 structure, with open betalactam ring, were synthesised and sIgE evaluated by RAST inhibition assay.

RESULTS

Tolerance to CX (Group A) was observed in 64.8% cases and cross-reactivity in 35.2% cases (Group B). Cross-reactivity with CO was only found in 1.8% cases from Group B. ST to CX showed a negative predictive value of 94.6%. RAST inhibition assays showed higher recognition to CX as well as to both synthetic determinants (66% of positive cases) in Group B.

CONCLUSIONS

Cross-reactivity with CX in AX allergic patients is 35%, being ST not enough for prediction. R1, although critical for recognition, is not the unique factor. The synthetic determinants of CX, 1-(HOPhG-Ser-Bu) and 2-(pyrazinone) are promising tools for determining in vitro cross-reactivity to CX in AX allergic patients.

The role of allergen-specific IgE in predicting allergic symptoms on dog and cat exposure among Korean pet exhibition participants

BACKGROUND

The values of the skin prick test (SPT) and allergen-specific IgE (sIgE) measurement in predicting dog and cat allergies remain unclear. We aimed to evaluate the usefulness of SPT and sIgE measurement in predicting self-reported allergic symptoms during exposure to dogs and cats in Korean adults.

METHODS

A total of 552 participants in a pet exhibition in Korea completed questionnaires regarding exposure to dog or cat and the development of allergic symptoms during exposure. Study participants also underwent SPT using 3 different commercially available reagents, and had their blood drawn for measurement of serum total IgE and dog/cat-dander-IgE using ImmunoCAP®.

RESULTS

Measurement of sIgE for dog and cat dander allergens provided the highest positive and negative predictive values and sensitivity, but not specificity (58%, 87.2%, 67.9%, and 93.1% for allergic symptoms on dog exposure; 64.7%, 83.2%, 74.8%, and 88.9% for those on cat exposure, respectively), in predicting self-reported allergic symptoms on dog and cat exposure. The sIgE level consistently exhibited the highest area under the receiver operating characteristic curve (0.749 and 0.719 for allergic symptoms on dog and cat exposure, respectively). Careful interpretation of SPT and sIgE measurements maximized the positive and negative predictive values, sensitivity, and specificity for predicting allergic symptoms on dog exposure (71.4%, 87.3%, 75.3%, and 99.3%) and those on cat exposure (71.4%, 85.3%, 79.3%, and 98.9%).

CONCLUSIONS

The measurement of dog and cat dander sIgE levels may be useful for the exclusion of allergic symptoms related to pet exposure. Collective interpretation of SPT and sIgE tests facilitates identification of allergic symptoms on dog or cat exposure, giving a better rule-in test result.

Accurate Prediction of Peanut Allergy in One-Third of Adults Using a Validated Ara h 2 Cutoff

BACKGROUND

The diagnostic value of peanut components is extensively studied in children, but to a lesser extent in adults with suspected peanut allergy. The use of peanut components in daily practice may reduce the need for double-blind placebo-controlled food challenges (DBPCFCs); however, validation studies are currently lacking.

OBJECTIVE

To evaluate the diagnostic value of (combined) peanut components and validate a previously found Ara h 2 cutoff level with 100% positive predictive value (PPV) in adults with suspected peanut allergy.

METHODS

Adults who underwent a peanut DBPCFC were included: 84 patients from a previous study (2002-2012) and 70 new patients (2012-2019). Specific IgE (sIgE) to peanut extract, Ara h 1, 2, 3, 6, and 8 was measured using ImmunoCAP. Diagnostic value was assessed with an area under the curve (AUC) analysis.

RESULTS

In total, 95 (62%) patients were peanut allergic. sIgE to Ara h 2 and Ara h 6 were the best predictors with an AUC (95% confidence interval) of 0.85 (0.79-0.91) and 0.85 (0.79-0.92), respectively. The Ara h 2 cutoff level with 100% PPV (≥1.75 kU_A/L) was validated in the 70 new patients. Thirty percent of all included patients could be classified correctly as peanut allergic using this validated cutoff level.

CONCLUSION

sIgE to Ara h 2 and Ara h 6 have equally high discriminative ability. Peanut allergy can be predicted accurately in one-third of adults using a validated cutoff level of sIgE to Ara h 2.

[Pitfalls in the diagnostics of food allergies in children and adolescents]

For the diagnostics of food allergies several points need to be considered. Firstly, it is important to recognize the various clinical pictures that can be caused by a food allergy. The assignment to a disease decides which further examinations are necessary and reasonable. In immunoglobulin (Ig) E‑mediated allergies, the detection of sensitization by determining the specific IgE or the prick test in addition to the medical history is an important mainstay of the diagnostics. Crucial is the fact that the detection of a sensitization against an extract from an allergen source only rarely implies an actual allergy. The majority of positive findings are not clinically relevant. The modern procedure of component-resolved allergy diagnostics improves the significance. Nevertheless, the diagnosis can often only be achieved by oral provocation tests. This article points out possible difficulties with the interpretation of the findings.

Polyvalent Mechanical Bacterial Lysate Administration Improves the Clinical Course of Grass Pollen-Induced Allergic Rhinitis in Children: A Randomized Controlled Trial

BACKGROUND

Recent studies highlight the immunoregulatory potential of bacterial lysates, indicating their potential use in the prevention and treatment of allergic diseases.

OBJECTIVE

To investigate the clinical efficacy of polyvalent mechanical bacterial lysates (PMBLs) in children with grass pollen-induced allergic rhinitis.

METHODS

Seventy children with seasonal allergic rhinitis were enrolled to this study and were randomly assigned to the PMBL and placebo groups. Severity of seasonal allergic rhinitis symptoms was assessed by the total nasal symptom score, total ocular symptom score, and visual analogue scale. During 3 visits, peak nasal inspiratory flow was measured, and nasal smears for the presence of eosinophils and nasal lavage fluids for the presence of allergen-specific IgE against timothy grass pollen allergens were sampled.

RESULTS

A statistically significant decrease in total nasal symptom score (P = .001), total ocular symptom score (P = .04), and visual analogue scale score for nasal and eye symptoms (P < .001 and P < .001, respectively) and an increase in peak nasal inspiratory flow (P = .04) were observed in the PMBL group versus the placebo group. During the grass pollen season, an increase and then a decrease in the number of eosinophils in nasal smears was observed in both groups; however, the number of eosinophils was significantly lower in the PMBL group versus the placebo group. No significant changes in allergen-specific IgE concentrations were observed in the PMBL group, whereas in the placebo group a statistically significant increase in allergen-specific IgE concentration was observed.

CONCLUSIONS

Sublingual administration of PMBLs during the grass pollen season offers significant efficacy in alleviating seasonal allergic rhinitis symptoms in children sensitized to grass pollen allergens. PMBLs probably affect mucosal immunity, weakening the response of T_H2 cells.

Serum level and clinical significance of vitamin E in children with allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is one of the most prevalent allergic diseases in children. This study aimed to investigate the association between serum concentrations of vitamin E and AR to determine if the vitamin E level is correlated with the occurrence and severity of AR.

METHODS

A total of 113 children were enrolled in this cross-sectional study. Sixty-five children in the outpatient group were diagnosed with AR, and 48 healthy children were recruited as controls. All subjects underwent serum vitamin E (adjusted for total cholesterol and triglycerides) measurements. Serum to total IgE (tIgE), the five most common allergen-specific IgE (sIgE) levels and skin prick test (SPT) were measured in children with AR. The severity of AR was assessed with the nasal symptoms score, and the situation of exposure to passive smoking were inquired.

RESULTS

Serum vitamin E levels were significantly lower in the AR group than in the normal children (P < 0.001). A significant negative correlation was observed between serum vitamin E levels and sIgE as well as the SPT grade. Serum vitamin E levels were also inversely related to the nasal symptoms score; however, statistical significance was not found.

CONCLUSIONS

A significantly lower vitamin E level was found in children with AR. Lower serum vitamin E levels may have correlation with the occurrence of AR in children. However, serum vitamin E levels were not statistically correlated with the severity of AR.

Molecular Sensitization Profile to Dermatophagoides pteronyssinus Dust Mite in Portugal

OBJECTIVE

To analyze component resolved diagnosis to Dermatophagoides pteronyssinus (Der p) in patients with respiratory allergy and its relationship with clinical severity in different geographical areas.

METHODS

217 patients (mean age 25.85±12.7 years; 51.16% females) were included, selected from 13 centers in Portugal (5 from North, n=65). All had allergic rhinitis, with or without asthma, and had positive skin prick tests to at least one dust mite. Specific IgE (sIgE) to Der p, Dermatophagoides farinae, Lepidoglyphus destructor, Der p1, Der p 2, Der p 10 and Der p 23 were determined by ImmunoCAP. Statistical analysis (Mann Whitney U test) compared patients with rhinitis vs rhinitis and asthma; mild vsmoderate-to-severe rhinitis; North vs South.

RESULTS

Prevalence of sensitization was 98.2% to Der p, and 72.4%, 89.4%, 9.7% and 77% to Der p 1, Der p 2, Der p 10 and Der p 23, respectively. Corresponding median sIgE levelswere 8.56, 17.7, 0.01 and 3.95 kUA/L. sIgE to all allergens was higher in patients with moderate-to-severe rhinitis and rhinitis with asthma but not statistically significant (NSS). sIgE to Der p 2 was significantly higher in the South when compared with the North (p=0.0496).

CONCLUSIONS

sensitization to Der p is the most common in Portugal. Der p 2 had the highest prevalence and median sIgE levels. All sIgE to molecular components were higher in more symptomatic patients (NSS). sIgE to Der p 2 was higher in the South, which may be related to the warmer temperature and/or the larger sample size.

Reduced polyfunctional T cells and increased cellular activation markers in adult allergy patients reporting adverse reactions to food

Background

The underlying cellular mechanisms causing adverse reactions to food are complex and still not fully understood. Therefore, in this study we aimed to identify functional and/or phenotypical immune cell signatures characteristic for adult patients reporting adverse reactions to food.

By mass cytometry, we performed high-dimensional profiling of peripheral blood mononuclear cells (PBMC) from adult patients reporting adverse reactions to food and healthy controls. The patients were grouped according to sIgE-positive or sIgE-negative serology to common food and inhalant allergens. Two broad antibody panels were used, allowing determination of major immune cell populations in PBMC, as well as activation status, proliferation status, and cytokine expression patterns after PMA/ionomycin-stimulation on a single cell level.

Results

By use of data-driven algorithms, several cell populations were identified showing significantly different marker expression between the groups.

Most striking was an impaired frequency and function of polyfunctional CD4+ and CD8+ T cells in patients reporting adverse reactions to food compared to the controls. Further, subpopulations of monocytes, T cells, and B cells had increased expression of functional markers such as CD371, CD69, CD25, CD28, and/or HLA-DR as well as decreased expression of CD23 in the patients. Most of the differing cell subpopulations were similarly altered in the two subgroups of patients.

Conclusion

Our results suggest common immune cell features for both patient subgroups reporting adverse reactions to food, and provide a basis for further studies on mechanistic and diagnostic biomarker studies in food allergy.

The Role of Aeroallergen Sensitization Testing in Asthma Management

Asthma is a global disease affecting almost 400 million people. Simultaneously, the overall burden of allergies is increasing. Although allergies are frequent and commonly recognized triggers of asthma severity and exacerbations, the majority of patients with asthma are not investigated for their underlying aeroallergen sensitizations, despite the potentially preventable consequences and therapeutic options. This review summarizes the current state of aeroallergen sensitization testing for people with asthma. We describe who should be tested and why, how testing can be used to optimize asthma management, list barriers to implementation of effective asthma management strategies, and make recommendations for improving asthma/allergy management by aeroallergen testing. Establishing a diagnosis of asthma and determining whether there is an allergic component is fundamental to an effective treatment plan. Moreover, moving from severity-based to phenotype-based asthma care can improve the care of asthma and allergic diseases. Timely diagnosis of aeroallergen sensitizations forms the basis for individualized treatment plans, which may include allergen remediation strategies when appropriate, and allergen immunotherapy, the only immunomodulating therapy for allergic asthma. Finally, the advent of biologics will expand the number of patients who can benefit from treatment, with decreased symptoms and disease remission a possibility for the first time.

Relationship between gut microbiota composition and sensitization to inhaled allergens

BACKGROUND

An imbalance in gut microbiota is implicated in several pathological conditions, including allergic diseases. This study investigates the association between gut microbiota composition and sensitization to two inhaled antigens.

METHODS

The study comprised 1109 local residents who had participated in the Iwaki Health Promotion Project in 2016. Blood samples were analyzed for levels of antigen-specific IgE against Japanese cedar pollen (JCP) and house dust (HD1). Fecal samples were analyzed for bacterial 16S rRNA (ribosomal ribonucleic acid) using next generation sequencing. The percent composition of gut microbes was compared between patients sensitized and unsensitized group for JCP and HD1 to determine whether the rate of sensitization to inhaled antigens associates with specific bacterial orders composing the gut microbiota.

RESULTS

In participants aged 20-49 years, the percent composition of Bacteroidales was significantly higher among participants sensitized to JCP than in those unsensitized. The percent composition of Lactobacillales was significantly higher in participants unsensitized to HD group than in those sensitized to that antigen. In addition, participants with low Bacteroidales and high Bifidobacteriales or Lactobacillales has low sensitization rates to HD compared with high Bacteroidales and low Bifidobacteriales or Lactobacillales.

CONCLUSIONS

The presence of bacteria of order Lactobacillales, Bifidobacteriales, and Bacteroidales in the gut microbiota may affect sensitization to inhaled allergens.

Improvement of the sensitivity of the detection of Gal d 6-specific IgE via biotinylation in vivo

INTRODUCTION AND OBJECTIVES

This study aimed to compare the effects of different biotinylation methods on the performance characteristics of allergen-specific IgE detection.

MATERIALS AND METHODS

The Gal d 6 gene was cloned into the pAN6/pAC6 vector, resulting in rGal d 6-Bio/Bio-rGal d 6 vector. The fusion protein was expressed in Escherichia coli AVB101 and simultaneously biotinylated in a site-specific manner. The Gal d 6 gene was amplified via PCR and cloned into the pET-28a vector and transformed into E. coli BL21 and purified via Ni-NTA, followed by chemical biotinylation using Sulfo-NHS-LC-Biotin. Twenty-eight patients allergic to hen's egg white were examined for sensitization against egg yolk. An antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) was developed to detect allergen-specific IgE.

RESULTS

rGal d 6, Bio-rGal d 6, and rGal d 6 were prepared using different biotin binding modes to detect allergen-specific IgE. rGal d 6-Bio (Kd=0.6154) and Bio-rGal d 6 (Kd=0.6698) had a markedly better detection performance than rGal d 6 (Kd=28.93), and the rGal d 6-Bio had a better detection performance in small-volume serum samples.

CONCLUSIONS

rGal d 6-Bio improved the sensitivity for the detection of allergen-specific IgE.

Sensitization to storage proteins in peanut and hazelnut is associated with higher levels of inflammatory markers in asthma

Background

Sensitization to peanuts and hazelnuts is common among young asthmatics and can be primary or a result of cross-reactivity. Sensitization as a result of cross-reactivity to birch pollen is typically associated to tolerance or mild and local symptoms upon intake of peanut or hazelnut.

Aim

The aim of this study was to investigate relationships between IgE antibody responses against peanut and hazelnut components, airway and systemic inflammation markers, lung function parameters and reported food hypersensitivity in a cohort of asthmatic children and young adults.

Methods

A population of 408 asthmatic individuals aged 10-35 years were investigated. Information on hypersensitivity symptoms upon intake of peanut or hazelnut were recorded in a standardized questionnaire. Fraction of exhaled nitric oxide (FeNO), blood eosinophil count (B-Eos), spirometry, methacholine challenge outcome and IgE antibodies to peanut and hazelnut allergens were measured by standard clinical and laboratory methods.

Results

Subjects sensitized to any of the peanut (Ara h 1, 2 or 3) or hazelnut (Cor a 9 or 14) storage proteins were significantly younger (17.6 vs 21.2 years), had higher levels of FeNO (23.2 vs 16.7 ppb) and B-Eos (340 vs 170 cells/mcl) than those displaying only pollen-related cross-reactive sensitization. Levels of FeNO correlated with levels of IgE to storage proteins in children, but not in adults. Levels of B-Eos correlated with levels of IgE to all allergen components investigated in children, but only to levels of IgE to storage proteins in adults. Anaphylaxis and skin reactions upon intake of peanuts or hazelnuts were more often reported among subjects sensitized to the respective storage proteins than among those with only pollen-related cross-reactive sensitization. As compared to peanut, hazelnut was more often reported to cause gastrointestinal symptoms and less often oral cavity symptoms.

Conclusions

Sensitization to peanut and hazelnut storage proteins was associated with higher levels of inflammation markers and food hypersensitivity symptoms in this population of subjects with asthma.

Development of the Microbiota and Associations With Birth Mode, Diet, and Atopic Disorders in a Longitudinal Analysis of Stool Samples, Collected From Infancy Through Early Childhood

BACKGROUND & AIMS

Establishment of the gastrointestinal microbiota during infancy affects immune system development and oral tolerance induction. Perturbations in the microbiome during this period can contribute to development of immune-mediated diseases. We monitored microbiota maturation and associations with subsequent development of allergies in infants and children.

METHODS

We collected 1453 stool samples, at 5, 13, 21, and 31 weeks postpartum (infants), and once at school age (6-11 years), from 440 children (49.3% girls, 24.8% born by cesarean delivery; all children except for 6 were breastfed for varying durations; median 40 weeks; interquartile range, 30-53 weeks). Microbiota were analyzed by amplicon sequencing. Children were followed through 3 years of age for development of atopic dermatitis; data on allergic sensitization and asthma were collected when children were school age.

RESULTS

Diversity of fecal microbiota, assessed by Shannon index, did not differ significantly among children from 5 through 13 weeks after birth, but thereafter gradually increased to 21 and 31 weeks. Most bacteria within the Bacteroidetes and Proteobacteria phyla were already present at 5 weeks after birth, whereas many bacteria of the Firmicutes phylum were acquired at later times in infancy. At school age, many new Actinobacteria, Firmicutes, and Bacteroidetes bacterial taxa emerged. The largest increase in microbial diversity occurred after 31 weeks. Vaginal, compared with cesarean delivery, was most strongly associated with an enrichment of Bacteroides species at 5 weeks through 31 weeks. From 13 weeks onward, diet became the most important determinant of microbiota composition; cessation of breastfeeding, rather than solid food introduction, was associated with changes. For example, Bifidobacteria, staphylococci, and streptococci significantly decreased on cessation of breastfeeding, whereas bacteria within the Lachnospiraceae family (Pseudobutyrivibrio, Lachnobacterium, Roseburia, and Blautia) increased. When we adjusted for confounding factors, we found fecal microbiota composition to be associated with development of atopic dermatitis, allergic sensitization, and asthma. Members of the Lachnospiraceae family, as well as the genera Faecalibacterium and Dialister, were associated with a reduced risk of atopy.

CONCLUSIONS

In a longitudinal study of fecal microbiota of children from 5 weeks through 6 to 11 years, we tracked changes in diversity and composition associated with the development of allergies and asthma.

Analysis of Sensitization Profiles in Central European Allergy Patients Focused on Animal Allergen Molecules

INTRODUCTION

Frequently observed multiple sensitizations to several animals highlights the importance of a molecular diagnosis, distinguishing between sensitizations specific to single species and sensitizations due to cross-reactivity.

OBJECTIVE

The aim of our study was to assess the usefulness of a molecular diagnosis in the description of sensitization profiles in allergy patients living in Central Europe, with a particular focus on animal-derived molecules.

METHODS

The molecular diagnosis was performed using the ImmunoCAP ISAC microarray. Results of 1,255 allergy patients were subjected to statistical analysis.

RESULTS

The highest sensitization rates were observed for uteroglobin Fel d 1 (31.8%) and kallikrein Can f 5 (16.4%), followed by animal lipocalins Can f 1 (13.9%), Equ c 1 (6.2%), Fel d 4 (5.3%), Can f 2 (4.2%), and Mus m 1 (4.1%). Sensitization rates to serum albumins Fel d 2, Can f 3, Equ c 3, and Bos d 6 were very low, with the highest being 3.2% to Fel d 2. Detailed subanalysis confirmed the dominant role of Fel d 1 or Can f 5 and/or Can f 1 in cat- or dog-sensitized patients, respectively. Further analysis focused on lipocalins and albumins confirmed a high rate of cosensitizations within both groups.

CONCLUSION

The sensitization to animal allergen molecules is very frequent in Central Europe. The most common is sensitization to species-specific cat uteroglobin Fel d 1 and dog kallikrein Can f 5, followed by sensitizations to animal lipocalins. Our data suggest that commonly observed multiple sensitizations detected by extract approach can be explained not only by true cosensitization, but also by cross-reactivity, mainly in the frame of lipocalins. Cross-reactive serum albumins are minor sensitizers and are probably not important from this point of view.

Allergic children with extremely high total IgE but no allergen identified in the initial screening panel

BACKGROUND

High serum IgE level in atopic children usually implies a highly sensitized condition. However, there is a subgroup of atopic children for whom a specific allergen cannot be identified. In this study, we analyzed follow-up data from these children.

METHODS

From March 2014 to July 2017, we recruited 14 atopic children with serum total IgE level higher than 500 Ku/L, but with no specific allergen identified by repeated MAST tests initially. Follow-up studies of specific IgE were conducted by the OPTIGEN MAST Allergy test and ImmunoCAP assays (Thermo Fisher Scientific/Phadia), while total IgE and specific IgG were measured by ImmunoCAP.

RESULTS

The patients were aged from 2 to 17 y/o. The follow-up MAST tests showed significantly positive results in 10 patients. There were no significant differences in any of the clinical characteristics between the MAST-positive and MAST-negative groups. In the MAST-negative group, five allergen-specific IgE antibodies, including those for cockroach, Euroglyphus maynei, Blomia tropicalis, shrimp, and crab, were strongly predictive of negative ImmunoCAP results, according to ROC (Receiver operating characteristic curve) analysis of the AUC (Area under the Curve of ROC) (0.70-0.95), with significance set at p < 0.05.

CONCLUSION

In two thirds of atopic children with a high serum IgE whose specific allergen had yet to be identified, it was possible to identify the specific MAST allergen(s) after an average follow-up of 33.2 months. For patients who still had negative results in follow-up MAST, mite DP, DF, and DM may be suitable choices for further allergen identification by ImmunoCAP.

Clinical and Laboratory Findings of Barley Allergy in Korean Children: a Single Hospital Based Retrospective Study

BACKGROUND

Barley is a grain that is consumed in various forms in Asia. Studies on barley allergy are limited to a few case reports about hypersensitivity reactions to beer, but there is no barley allergy study in children. This study aimed to identify the phenotype and immunologic findings in Korean children with barley allergy.

METHODS

Forty-two participants with a history of ingesting barley who underwent serum specific immunoglobulin E to barley (barley-sIgE) assay at the Department of Pediatrics in Ajou Medical Center were enrolled through a retrospective analysis of medical records from March 2008 to February 2018. The demographic characteristics, symptoms, and immunologic parameters of the patients were assessed.

RESULTS

Twenty subjects presented with clinical barley allergy (B-allergic group), and 22 were atopic controls without allergic reactions after the ingestion of barley (B-tolerant group). The median ages of the B-allergic and B-tolerant groups were 1 and 3 years, respectively. In the B-allergic group, the cutaneous system (90.0%) was most frequently affected, followed by the respiratory system (40.0%). Anaphylaxis was observed in 35.0% of the B-allergic group. The median level of barley-sIgE was 13.90 kU_A/L (range, 0.14-101.00 kU_A/L) in the B-allergic group, and this value was significantly higher (P < 0.001) than that of the B-tolerant group (0.30 kU_A/L; range, 0.01-24.40 kU_A/L), with an optimal cutoff level of 1.24 kU_A/L (sensitivity, 85.0%; specificity, 86.4%). A positive correlation was found between the serum levels of barley-sIgE and wheat-sIgE in the B-allergic group with clinical wheat allergy.

CONCLUSION

Barley is an important allergen for children in Korea. This study showed the clinical characteristics of barley allergy and suggested optimal cut-off levels of barley-sIgE for clinical barley allergy. Clinically, cross-reactivity or co-sensitization is often observed between barley and wheat.

Exercise Lowers Threshold and Increases Severity, but Wheat-Dependent, Exercise-Induced Anaphylaxis Can Be Elicited at Rest

BACKGROUND

Wheat-dependent, exercise-induced anaphylaxis (WDEIA) is a severe form of allergy in which exercise is being considered as mandatory. The diagnosis is often complex and the clinical reproducibility low.

OBJECTIVE

The aims of this study were to establish a standardized challenge method for the diagnosis of WDEIA and to investigate whether exercise is an essential trigger factor or alternatively an augmentation factor able to lower threshold and increase severity.

METHODS

We investigated 71 patients (age, 18.6-73.7 years) with a case history of WDEIA. Skin prick test (SPT) and measurement of specific IgE (sIgE) were followed by an oral food challenge with gluten at rest and in combination with treadmill exercise.

RESULTS

A clinical reaction was elicited in 47 of 71 (66%), and in 26 of these (37%) the reaction could be elicited at rest. The median dose required at rest was 48 g (8-80 g) and in combination with exercise 24 g (4-80 g). Severity was significantly higher with exercise (2.3) than at rest (1.1) using Sampson severity score. In the challenge, SPT was positive to wheat in 93.6% (44 of 47) and to gluten in 95.7% (45 of 47). sIgE to wheat, gliadin, and omega-5 gliadin was present in 78.7% (37 of 47), 76.5% (36 of 47), and 91.4% (43 of 47) of the patients. Receiver operating characteristic-curve analysis for sIgE to omega-5 gliadin, a component of the gluten fraction and the major allergen in WDEIA, showed best sensitivity (91%) and specificity (92%) when gluten was combined with exercise.

CONCLUSIONS

A challenge test with gluten at rest and combined exercise is a safe confirmatory test for WDEIA. A reaction can be elicited at rest (without exercise), but exercise is able to lower the threshold and increase the severity.

Mold Sensitization in Asthmatic and Non-asthmatic Subjects Diagnosed with Extract-Based Versus Component-Based Allergens

Asthmatic patients are suspected of having a higher risk of mold sensitization. Thus, precise diagnosis of fungal sensitization is important. Mold allergen extracts are difficult to standardize, but component-resolved allergy diagnosis may be an alternative to replace extract-based tests. In this research, asthmatic and non-asthmatic subjects were studied for their sensitization to Aspergillus fumigatus (Asp f), Cladosporium herbarum (Cla h), Penicillium chrysogenum (Pen ch), Alternaria alternata (Alt a), and Aspergillus versicolor (Asp v). Extract-based tests were applied using the skin prick test (SPT) and allergen-specific immunoglobulin E (sIgE). Subjects with extract-based sensitization to Asp f or Alt a were further investigated for sIgE response to recombinant (r) single mold allergens. At least one mold sensitization was found in about 50% of asthmatic and non-asthmatics with the most frequent sensitization to Alt a, followed by Pen ch, Asp f, Cla h, and Asp v. Interestingly, sensitization rate to individual mold species was always higher in asthmatics and was only significant for Pen ch. The component-resolved diagnosis with the sum of rAsp f 1 - rAsp f 4 plus rAsp f 6 matched the extract-based results (SPT and/or sIgE) in 50% of asthmatics and 46% of non-asthmatics, whereas, rAlt a 1 covered 59% of asthmatics and 50% non-asthmatics of extract-based Alt a sensitization. In conclusion, individual fungal sensitization rate was higher in asthmatics compared to non-asthmatics. Extract-based tests, especially SPTs, were most sensitive, but component-based tests covered 80% of extract-based serological sensitization to Alternaria and Aspergillus.

Allergy and the Pediatric Otolaryngologist

Food allergy and allergic rhinitis are childhood diseases with special relevance to the pediatric otolaryngologist. Much of the diagnosis of food allergy can be made on history alone; strict avoidance is the mainstay treatment. Skin prick testing and serum-specific IgE testing play a stronger role in allergic rhinitis diagnosis. If pharmacotherapy fails, allergen immunotherapy is an option. Currently, there is intense investigation on diagnostic tests, novel treatments, and prevention strategies that could dramatically affect the way these diseases are identified and managed. This article summarizes the epidemiology, pathophysiology, diagnosis, and management of food allergy and allergic rhinitis.