Molecular diagnosis and immunotherapy selection in a Portuguese population sensitized to grass and olive pollens / Diagnóstico molecular e seleção de imunoterapia numa população portuguesa sensibilizada ao pólen de gramíneas e de oliveira

Introduction: Phleum pratense (Phl p) and Olea europaea (Ole e) are common allergenic pollen. Objectives: To describe the sensitization patterns to Phl p and Ole e allergens in a subset of allergic rhinitis patients with positive skin prick tests (SPTs) to these pollens and compare the allergen immunotherapy (AIT) choice before and after determination of molecular components. Methods: Candidates to pollen immunotherapy with positive SPTs to both Phl p and Ole e were recruited. All of them underwent an SPT with a panel of aeroallergens and measurements of serum specific IgE (sIgE) to Phl p, Ole e, Phl p1, Phl p5, Phl p7, Phl p12, Ole e1, Ole e7, and Bet v2. Results: Forty adults were included. Of these, 83% and 65% were sIgE-positive to Phl p and Ole e, using the 0.35 kUA/L and 0.70 kUA/L cut-offs, respectively. Moreover, 42.5% of patients had positive sIgE to Phl p1 and/or Phl p5, 2.5% only to Ole e1, and 47.5% to both (0.35 kUA/L cutoff). By increasing the cut-off to 0.7 kUA/L, 55% of patients were sensitized to Phl p1 and/or Phl p5, and no patient was sensitized only to Ole e1. After component-resolved diagnosis, AIT choice was changed in 15 (37.5%) patients, with a decrease in the number of prescriptions of AIT with both grass and olive pollens and with olive alone, together with an increase in the prescriptions of AIT with grass pollen alone. Conclusion: Genuine sensitization to Olea europaea was reduced, and the sensitization patterns were heterogeneous. Knowledge of pattern of sensitization to molecular components changed immunotherapy prescription in more than one third of the patients.

Introdução: Os polens de Phleum pratense (Phl p) e de Olea europaea (Ole e) são fontes alergênicas comuns. Objetivos: Descrever os padrões de sensibilização aos alergênios destes dois polens num subconjunto de pacientes com rinite alérgica polínica e comparar a escolha de imunoterapia, antes e depois da determinação de alergênios moleculares para Phl p e Ole e. Métodos: Foram recrutados candidatos para imunoterapia com polens, com testes cutâneos positivos para Phl p e Ole e. Todos realizaram um painel de testes em picada a aeroalergênios e determinação de IgE séricas específicas para Phl p, Ole e, rPhl p1, rPhl p5, rPhl p7, rPhl p 12, rOle e 1, nOle e 7, rBet v2. Resultados: Foram incluídos 40 adultos. Em relação à sIgE para Phl p e Ole e, 83% e 65% dos pacientes apresentaram positividade para ambos, usando o cut-off de 0,35 kUA/L e 0,70 kUA/L, respectivamente. A positividade para Phl p1 e/ou Phl p 5 foi encontrada em 42,5%, para Ole e 1 apenas em 2,5%, enquanto 47,5% apresentaram sIgE positivo para ambos (cut-off corte de 0,35 kUA/L). Aumentando o cut-off para 0,7 kUA/L, 55% foram sensibilizados para Phl p1 e/ou Phl p5, nenhum paciente foi sensibilizado apenas para Ole e 1. Após a determinação dos alergênios para os componentes moleculares, a escolha de imunoterapia foi alterada em 15 (37,5%) pacientes, com uma diminuição no número de vacinas para Phleum + Olea e apenas para Olea e um aumento na prescrição de vacinas para Phleum. Conclusão: A sensibilização genuína do Olea europaea foi reduzida e os padrões de sensibilização foram heterogêneos. O conhecimento da sensibilização aos componentes moleculares dos alergênios mudou a prescrição de imunoterapia em mais de um terço dos pacientes.

Profiles of IgE Sensitization to Der f 1, Der f 2, Der f 6, Der f 8, Der f 10, and Der f 20 in Korean House Dust Mite Allergy Patients

PURPOSE: Measurement of IgE specific to purified house dust mite (HDM) allergens may improve allergy diagnosis. This study aimed to investigate the sensitization profiles of Korean HDM allergic subjects suffering from respiratory allergy and atopic dermatitis (AD) to Der f 1, Der f 2, Der f 6, Der f 8, Der f 10, and Der f 20. METHODS: Recombinant HDM allergens were produced in Pichia pastoris (Der f 1) or Escherichia coli (5 allergens). IgE reactivity to the individual recombinant allergens and total extract of mite was assessed by ELISA. RESULTS: Der f 1 was recognized by 79.1%, Der f 2 by 79.1%, Der f 6 by 9.3%, Der f 8 by 6.2%, Der f 10 by 6.2%, and Der f 20 by 6.6% of the patients' sera tested, while the prevalence of IgE reactivity to total mite extract was 94.7%. Combination of Der f 1 and Der f 2 had a sensitivity of 87.6%. Specific IgE to Der f 2 alone was detected from 89.4% of HDM-sensitized respiratory allergy subjects and 92.3% to the combination of the 2 major allergens Der f 1 and Der f 2. However, sera from fewer patients with AD, namely 72.4% and 71.0%, recognized Der f 1 and Der f 2, respectively. The combination of 2 major allergens allowed diagnosis of 84.5% of the AD patients. No correlation between sensitization to specific allergens and HDM allergy entity was found. CONCLUSIONS: Der f 2 was the most frequently sensitized allergen among the HDM-sensitized respiratory and AD patients in Korea, and the combination of the group 1 and 2 major allergens increased the diagnostic sensitivity. Minor allergens did not significantly improve diagnostic sensitivity. However, further studies are needed to analyze the relationship between sensitization to other HDM allergens and the disease entity of the HDM allergy.

Clinical Features and the Diagnostic Value of Component Allergen-Specific IgE in Hymenoptera Venom Allergy

PURPOSE: Although patient history is vital for the diagnosis of hymenoptera venom allergy, specific IgE detection is also important to identify the culprit insect and monitor the effect of immunotherapy. We evaluated the diagnostic value of serum-specific IgE detection of hymenoptera venom component allergens and documented changes in allergen-specific IgE after immunotherapy. METHODS: Fifty-six hymenoptera venom allergy patients receiving venom immunotherapy were recruited from Ajou University Hospital, Korea. The clinical manifestations of the patients were noted, and serum-specific IgE detection was performed, using conventional venom extracts as well as component allergens. Data were analyzed retrospectively. RESULTS: A total of 35 (62.5%) patients were male, and 33 (73.3%) patients were atopic. The mean patient age was 44.9+/-13.8 years. Localized reactions occurred in 23.2% of patients, and systemic reactions occurred in 76.8%. The most common clinical manifestations included skin involvement, such as urticaria and angioedema, and respiratory involvement. Yellow jackets were the most frequent culprit insect, followed by yellow hornets, white-faced hornets, honeybees, and paper wasps, as determined at the time of diagnosis. Double sensitization to both Apidae and Vespidae species was detected in 70.9% of patients. The positive predictive values (PPV) of rVes v 5-specific and rPol d 5-specific IgE detection were 85.7% and 87.5%, respectively, which correlated well with conventional venom extract-specific IgE detection (r=0.762 and r=0.757, respectively). In contrast, the PPV of rApi m 1-specific IgE detection at the time of diagnosis was 34.8%. Three years of venom immunotherapy resulted in decreased venom-specific IgE, particularly IgE specific for Vespidae venom components. CONCLUSIONS: Stings by yellow jackets and male sex may be risk factors for hymenoptera venom allergy in Korea. Vespidae component-specific IgE, but not Apidae component-specific IgE, had diagnostic and monitoring value in hymenoptera venom allergy comparable to that of conventional hymenoptera venom extract-specific IgE.