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Background The responsiveness to a nonendemic grass species is unknown and cannot be research without an allergen challenge chamber. Objective To determine the clinical responsiveness to timothy grass pollen (TGP) in participants without known natural exposure in an allergen challenge chamber (ACC). Methods Of the 26 screened participants, 22 met screening criteria and completed the 2 chamber exposures. The study consisted of an initial screening visit that included a blood draw for serum specific IgE (ssIGE) to Bermuda grass pollen and TGP followed by a 4½-day run-in phase and two 3-hour ACC exposure visits. This study was performed early in the first week of December 2013, when no seasonal pollens were detected in San Antonio, Texas. Symptom scores were recorded at baseline and every 30 minutes. Results Of the 26 screened participants, 22 met the screening criteria and completed the 2 chamber exposures. Thirteen participants had always lived in South Texas without natural exposure, and 9 had previously lived in areas with TGP exposure. All participants tested positive to TGP and Bermuda grass pollen. Twelve and 13 of 22 had positive ssIgE test results to Timothy and Bermuda allergens, respectively, with 11 having positive results for both allergens. There were strong correlations among skin prick test size, a positive ssIgE test result, and high symptoms from TGP exposure. There was little difference in symptoms between those who had lived their entire lives in South Texas and those who had lived elsewhere. Conclusion In Texas, where exposure to TGP is minimal, strongly positive SPT and ssIgE test results were predictors of high symptoms to TGP exposure. Never exposed participants in South Texas reacted to TGP similar to those who had previous natural exposure, suggesting that in vivo cross-reactivity may be higher than predicted by prior in vitro data and may allow the use in clinical trials of allergens not endemic to the locale of an ACC.

BACKGROUND: Rhinitis and asthma are linked, but substantial knowledge gaps in this relationship exist. OBJECTIVE: To determine the prevalence of rhinitis and its phenotypes in children and adolescents with asthma, assess symptom severity and medication requirements for rhinitis control, and investigate associations between rhinitis and asthma. METHODS: 749 children with asthma participating in the Asthma Phenotypes in the Inner-City study received baseline evaluations and were managed for 1 year with algorithm-based treatments for rhinitis and asthma. Rhinitis was diagnosed by questionnaire focusing on individual symptoms, and pre-defined phenotypes were determined by combining symptom patterns with skin testing and serum specific IgE. RESULTS: Analyses were done on 619 children with asthma who completed at least 4 of 6 visits. Rhinitis was present in 93.5%, and phenotypes identified at baseline were confirmed during the observation/management year. Perennial allergic rhinitis with seasonal exacerbations (PARSE) was most common (34.2%) and severe. Nonallergic rhinitis was least common (11.3%) and least severe. The majority of children remained symptomatic despite the use of nasal corticosteroids ± oral antihistamines. Rhinitis was worse in difficult-to-control vs. easy-to-control asthma and its seasonal patterns partially corresponded to those of difficult-to-control asthma. CONCLUSION: Rhinitis is almost ubiquitous in urban children with asthma, and its activity tracks that of lower airway disease. PARSE is the most severe phenotype and most likely to be associated with difficult-to-control asthma. This study offers strong support to the concept that rhinitis and asthma represent the manifestations of one disease in two parts of the airways. CAPSULE SUMMARY: Almost all children and adolescents with asthma have rhinitis of various, stable phenotypes based on sensitization and seasonal pattern. Conventional medications control rhinitis symptoms only in a minority. Difficult-to- control asthma is associated with worse rhinitis.

Background Oral desensitization in children allergic to cow's milk proteins is not risk free. The analysis of factors that may influence the outcome is of utmost importance. Objective To analyze the efficacy and safety of the oral desensitization according to specific IgE (sIgE) level and adverse events during the maintenance phase. Methods Thirty-six patients allergic to cow's milk (mean age, 7 years) were included in an oral desensitization protocol. Patients were grouped according to sIgE levels (ImmunoCAP) into groups 1 (sIgE 17-50 kU/L). Nineteen children were included as a control group. Serum sIgE levels to cow's milk and its proteins were determined at inclusion and 6 and 12 months after finishing the desensitization protocol. Results Thirty-three of 36 patients were successfully desensitized (200 mL): 100% of group 1 and 88% of groups 2 and 3. Desensitization was achieved in a median of 3 months (range, 1-12 months); 90% of the patients in group 1, 50% of the patients in group 2, and 30% of the patients in group 3 achieved tolerance in less than 3 months ( P = .04). In the control group only 1 child tolerated milk in oral food challenge after 1 year. During the induction phase, there were 53 adverse events in 27 patients (75%). Patients of groups 2 and 3 had more severe adverse events compared with group 1. During the maintenance phase, 20 of 33 patients (60%) had an adverse event. Conclusion Oral desensitization is efficacious. Tolerance is achieved earlier when sIgE is lower. Severe adverse events are frequent, especially in patients with higher sIgE levels. Trial Registration clinicaltrials.gov Identifier: NCT01641731

Background Childhood food allergy is a serious health problem. However, little is known about the frequency and manner in which it is currently diagnosed. Objective To describe parent report of physician practices in the diagnosis of pediatric food allergy. Methods Data from children with food allergy were identified for analysis from a representative survey administered in US households with children from June 2009 to February 2010. Analyses were performed at the level of the allergy. Demographic characteristics, symptom prevalence, and diagnostic methods were calculated as weighted proportions. Adjusted models were estimated to examine the association of reaction history and allergenic food with odds of physician diagnosis and testing. Results Food allergies (n = 3,218) to 9 common allergens were reported among 2,355 children in a sample of 38,480. We found that 70.4% of reported food allergy was diagnosed by a physician. Among physician-diagnosed food allergy, 32.6% was not evaluated with diagnostic testing, 47.3% was assessed with a skin prick test, 39.9% with a serum specific IgE test, and 20.2% with an oral food challenge. Odds of physician diagnosis and testing were significantly higher for severe versus mild/moderate food allergy. Urticaria and angioedema were not reported as symptoms in 40.7% and 34.6% of severe food allergies, respectively. Conclusion Thirty percent of parent-reported food allergies in this study were not diagnosed by a physician. One in 5 physician-diagnosed allergies was evaluated with oral food challenge. Understanding parent report of practices in food allergy provides insight into ways in which to streamline the diagnosis and management of care.

Food allergy is a common medical problem in infants, children and teenagers. With a good history, appropriate allergy tests and some training, food allergy is relatively easy to diagnose. A correct diagnosis can allow the child to avoid the relevant allergens and reduce their risk of experiencing further allergic reactions. They and their families can also be taught how to recognize and manage any future reactions. This is important as allergenic foods can precipitate anaphylaxis, particularly in children with co-existing asthma. This article will provide a description of how to diagnose and manage infants, children and teenagers with possible food allergy.

Background The ability of prick puncture skin test (PPST) results and the presence of serum specific IgE (sIgE) to Dermatophagoides pteronyssinus to predict positive or negative nasal challenge (NC) results has not been determined in older adults. Objective To determine if allergy skin test and/or serum sIgE is diagnostic of allergic rhinitis in older adults. Methods Forty-eight adults (20 younger and 28 older) with rhinitis underwent NC to D pteronyssinus 1 to 4 weeks after PPST and sIgE to D pteronyssinus . Patients were not aware of their in vivo or in vitro results at the time of their NC. Results Fourteen of 48 adults (10 younger and 4 older) were NC positive. The positive predictive values for older adults with positive NC results ranged from 28.57% to 42.86% for PPST and was 16.67% for sIgE. In contrast, positive predictive values in younger adults ranged from 76.92% to 100% for PPST and was 100% for sIgE. However, negative PPST results and sIgE had high predictive values for a negative NC result to D pteronyssinus in older adults (90.48%-95.24% for PPST and 89.47% for sIgE). Conclusions Although PPST and sIgE negative results were good predictors of negative NC outcomes, neither positive PPST results nor serum sIgE to D pteronyssinus predicted positive NC results in older adults. PPST and sIgE to D pteronyssinus were excellent predictors of both positive and negative NC outcomes in younger adults.

Background Microarray technique is promising in allergy diagnosis. The aim of this study was to compare SPT with specific-IgE by microarray in a group of patients with rhinitis. Methods Cross-sectional study, 101 participants with rhinitis diagnosed according to ARIA (89.1% with asthma); age range 6 to 15 years. SPT was done with Dermatophagoides pteronyssinus (Dp), Blattella germanica (Bg), cat and dog allergenic extracts (IPI ASAC Brasil); a mean wheal diameter of ≥2 mm greater than the negative control was considered positive. Sera were analysed for allergen specific IgE antibodies to Dp (Der p 1, Der p 2), Bg (Bla g 1, Bla g 2, Bla g 4, Bla g 5), cat (Fel d 1, Fel d 2) and dog (Can f 1, Can f 2) allergens using a microarray system (ImmunoCAP ISAC, PMD, Austria), considered positive ≥0.3 ISU (ISAC standardized units). Categorical variables were shown as percentage and differences between the 2 methods verified by chi-square test; P < 0.05 was considered significant. Results SPT was positive to Dp in 88.1% whereas ISAC was positive to Der p 1 in 74.2% (P < 0.001) and Der p 2 in 73.3% (P < 0.01) respectively. Sensitivity of SPT was 97% and specificity was 38%. The remaining allergens caused less SPT reactions (cockroach 25.7%, cat 22.8%, dog 27.7%) and these were associated with lower detection of specific-IgE by ISAC respectively Bla g 1 (0.9%, P = 0.09), Bla g 2 (0%), Bla g 4 (0%), Bla g 5 (0.9%, P = 0.55); Fel d 1 (16.8%, P < 0.01), Fel d 2 (0.9%, P = 0.06); Can f 1 (4.9%, P = 0.53), Can f 2 (2.9%, P < 0.001). Conclusions SPT remains the favored method to detect IgE-mediated sensitivity to aeroallergens. SPT was highly sensitive for Dp though less specific in comparison with the IgE microarray to Der p 1 and Der p 2 allergens.

Background Although history taking is primary method in the diagnosis of bee venom allergy, serum specific IgE detection is critical to identify causative bee and assess the effect of immunotherapy. Component-resolved diagnosis (CRD) in allergy has been used for its high sensitivity and specificity in many allergy diseases caused by food, cat, birch, and grass pollens. The purposes of this study are to evaluate diagnostic value of serum specific IgE to 3 bee venom component allergens and observe the changes of allergen specific IgE during bee venom immunotherapy. Methods Fifty-six bee venom anaphylaxis patients receiving bee venom immunotherapy were recruited from Ajou University Hospital. Clinical manifestations and serum specific IgE levels to bee venoms and component allergen (rApi m1 of Apidae, rVes v5 and rPol d5 of Vespidae) measured by using ImmunoCAP (Phadia, Sweden) were analyzed retrospectively. Results Thirty-five (62.5%) patients were male and 33 (73.3%) were atopics. Their mean age was 44.9 ± 13.8 years ranged from 11 to 73 years. Local reactions were found in 13 (23.2%) patients, while systemic reactions, in 43 (76.8%) patients. The most frequent manifestation was anaphylaxis which were severe (37.5%) and moderate (39.3%) manifestations followed by urticaria and angioedema. Yellow Jacket (80.8%) was the most prevalent bee followed by yellow hornet, white faced hornet, honey bee and paper wasp at the time of diagnosis with concurrent sensitization in both Apidae and Vespidae at 70.9% patients. The positive predictive value (PPV) of serum specific IgE levels to rVes v5 and rPol d5 were 85.7 and 87.5%, and they significantly correlated with conventional serum specific IgE level (r = 0.762 and r = 0.757, respectively), however, PPV of rApi m1 was only 34.8% at the time of initial diagnosis. After 3 years of bee venom immunotherapy, all kinds of bee venom specific IgE levels tended to decline compared to those collected before allergen immunotherapy, especially in component specific IgE to Vespidae. Conclusions Yellow jacket sting and male gender may be risk factors for bee venom allergy in Korea. Component allergen specific IgE to Vespidae, not Apidae had a diagnostic and monitoring value comparable to conventional specific IgE in bee venom allergy.