Unraveling the Diagnosis of Kiwifruit Allergy: Usefulness of Current Diagnostic Tests.

OBJECTIVES: To determine the usefulness of the in vitro and in vivo methods used in the diagnosis of kiwifruit allergy and to specifically assess the impact of seed proteins on sensitivity. METHODS: We performed skin prick tests (SPTs) using various commercial extracts, homemade pulp, and seed extracts and prick-prick tests with kiwifruit on 36 allergic patients. The presence of specific IgE (sIgE) was assessed using the ImmunoCAP (kiwifruit extract), ELISA (Act d 1, Act d 2), ISAC, and FABER assays. Immunoblotting of seed extract was carried out, and a single-blind oral food challenge was performed with whole seeds in seed-sensitized individuals. RESULTS: The prick prick test with kiwifruit demonstrated the highest diagnostic capacity (81.8% sensitivity and 94.1% specificity) among the in vivo tests. The sIgE levels measured using ImmunoCAP (kiwifruit extract) showed a similar sensitivity to that of global ISAC and FABER (63.9%, 59.5%, and 58.3%, respectively). Act d 1 was the major allergen. Sensitization to Act d 1 was associated with positive sIgE results to whole kiwifruit extract detected by ImmunoCAP (P<.000). A positive SPT result to kiwifruit seeds was associated with severe symptoms induced by kiwifruit (P=.019) as a marker of advanced disease, but not with clinically relevant sensitization. Challenge testing with kiwifruit seeds performed on 8 seed-sensitized patients yielded negative results. CONCLUSION: Sensitization to Act d 1 is associated with a positive result in conventional diagnostic techniques, whereas kiwifruit seed sensitization does not increase the sensitivity of the diagnostic techniques evaluated.

Unraveling the Diagnosis of Kiwifruit Allergy: Usefulness of Current Diagnostic Tests

Objectives: To determine the usefulness of the in vitro and in vivo methods used in the diagnosis of kiwifruit allergy and to specificallyassess the impact of seed proteins on sensitivity.Methods: We performed skin prick tests (SPTs) using various commercial extracts, homemade pulp, and seed extracts and prick-prick testswith kiwifruit on 36 allergic patients. The presence of specific IgE (sIgE) was assessed using the ImmunoCAP (kiwifruit extract), ELISA(Act d 1, Act d 2), ISAC, and FABER assays. Immunoblotting of seed extract was carried out, and a single-blind oral food challenge wasperformed with whole seeds in seed-sensitized individuals.Results: The prick prick test with kiwifruit demonstrated the highest diagnostic capacity (81.8% sensitivity and 94.1% specificity) amongthe in vivo tests. The sIgE levels measured using ImmunoCAP (kiwifruit extract) showed a similar sensitivity to that of global ISAC andFABER (63.9%, 59.5%, and 58.3%, respectively). Act d 1 was the major allergen. Sensitization to Act d 1 was associated with positivesIgE results to whole kiwifruit extract detected by ImmunoCAP (P<.000). A positive SPT result to kiwifruit seeds was associated withsevere symptoms induced by kiwifruit (P=.019) as a marker of advanced disease, but not with clinically relevant sensitization. Challengetesting with kiwifruit seeds performed on 8 seed-sensitized patients yielded negative results.Conclusions: Sensitization to Act d 1 is associated with a positive result in conventional diagnostic techniques, whereas kiwifruit seedsensitization does not increase the sensitivity of the diagnostic techniques evaluated (AU)

Objetivos: Determinar la rentabilidad diagnóstica de las técnicas in vitro e in vivo utilizadas en el diagnóstico de alergia al kiwi y estudiarla influencia de las proteínas alergénicas de las semillas en su sensibilidad.Métodos: Se seleccionaron 36 pacientes alérgicos a kiwi. Se les realizó prick test con cuatro extractos comerciales diferentes y prick-prickcon kiwi. Se determinó IgE específica mediante ImmunoCAP (extracto de kiwi), ELISA (Act d 1, Act d 2), las micromatrices ISAC y FABER eImmunoblotting de extracto de semilla de kiwi. Se realizó exposición oral simple ciego frente a semilla de kiwi en pacientes sensibilizadosa la semilla.Resultados: El prick-prick de kiwi fue la prueba in vivo con mayor rendimiento (sensibilidad 81,8%, especificidad 94,1%). El ImmunoCAPde extracto de kiwi mostró una sensibilidad similar a la global del ISAC y del FABER (63,9%, 59,5% y 58,3%, respectivamente). Act d 1fue el alérgeno mayoritario. Se encontró asociación entre los niveles de IgE específica frente a Act d 1 (ISAC) y el extracto de kiwi medianteImmunoCAP (p <0,000). La prueba cutánea positiva con semilla se asoció con mayor gravedad de síntomas frente a kiwi (p = 0,019),como marcador de enfermedad avanzada, pero no como sensibilización clínicamente relevante. La prueba de provocación con semillasfue negativa en los ocho pacientes provocados.Conclusiones: La sensibilización a Act d 1 se asocia con resultados positivos con las técnicas diagnósticas convencionales. La sensibilizaciónfrente a semillas no mejora el rendimiento de las técnicas evaluadas (AU)

[Analysis of clinical safety in the units of Allergy of the Valencian Community]. / Análisis de la seguridad clínica en las unidades de Alergología de la Comunidad Valenciana.

The introduction of new diagnostic and therapeutic procedures involving allergen exposure may increase the risk of allergic reactions. We designed and distributed an anonymous questionnaire among the allergy units of the Valencian Community in order to collect information on measures to ensure clinical safety. Twelve hospital outpatient clinics and 8 ambulatory care centres reported similar patterns of activities, including the use of critical care units, emergency rooms or day hospitals for higher risk techniques. The provision of security-related instruments is broader in hospital outpatient clinics and included: oxygen (91.7%), pulse oximeter (75.0%) or vital signs monitor (8.3%), resuscitation material (91.7%) and defibrillator (83.3%). The response time for emergencies is set in 50% of clinics. The resuscitation material is systematically reviewed and informed consent signed. Security is more limited in ambulatory care centres. It is necessary to set down the conditions for clinical safety in allergology. Key words. Allergy. Ambulatory care. Clinical safety. Health services. Hospital outpatient clinic.

Discriminant analysis in allergic rhinitis and asthma: methacholine dose-response slope allows a good differentiation between mild asthma and rhinitis.

Asthma and rhinitis frequently coexist in allergic patients, but nasal symptoms may predominate, leading to asthma underdiagnosis and undertreatment. Discriminant analysis obtains the best differentiation between groups using one or one set of variables. Our aim was to identify the laboratory test [allergen exposure, total and specific serum IgE, lung function, blood eosinophils and, bronchial response and sensitivity to methacholine (Mth) and allergen] or combination of them that allowed the best differentiation between mild asthma and allergic rhinitis. A cross-sectional analysis was performed in 86 Dermatophogoides pteronyssinus allergic rhinitis patients, who were classified according to clinical data as rhinitis plus mild asthma (n = 62) or "pure" rhinitis (n = 24). Bronchial symptoms had been exhaustively evaluated during a 2-years pre-inclusion period. Patients underwent skin tests and bronchial challenge with Mth and allergen. The exposure to D. pteronyssinus allergen (Der pl) was quantified in dust samples. Dose-response curves with Mth [until the FEV1 fell by 40% or the maximal dose (200 mg/ml) was inhaled] were attained. We developed multiple models of discriminant analysis in order to evaluate the capacity of the above variables to differentiate groups. Asthma patients had higher total and specific IgE levels and a greater sensitivity (PD20 values) and response [dose-response slope (DRS)] to both Mth and allergen. The model entering these variables was the one that correctly classified more patients (79.2%). The discriminative power of the model that only included Mth-DRS values was similar to the above (78.8%). Bronchial response to Mth is quantitatively different in allergic rhinitis patients who display mild asthma symptoms when compared to those that only report rhinitis, suggesting a distinct bronchial intrinsic behavior. The utilization of complete dose-response curves with Mth allows a good separation between mild asthma and "pure" rhinitis patients and might be useful in the diagnosis of mild asthma. Whether the early detection and treatment of these patients prevents the development of symptomatic asthma needs further evaluation.

Analysis of induced sputum: a new approach to the study of airway inflammation in asthma.

Induced sputum is a simple method that enables the analysis of lower respiratory tract material obtained through non-invasive methods. Validation of the technique for the study of airway inflammation in asthma and other respiratory diseases, together with the most relevant findings reported in the literature, are reviewed herein. Accurate methods that can be applied to the analysis of induced sputum samples, such as immunocytochemistry, flow cytometry or polymerase chain reaction are also discussed.

Olerance of a cluster schedule with a house dust mite extract quantified in mass units: multicentre study.

The standardisation of allergenic extracts in micrograms of the major allergen has encouraged the search for new treatment schedules, with the purpose of shortening the number of visits and doses required to reach the maintenance dose without eliciting a greater risk of adverse reactions for the patients. With this objective, a prospective multicentre pharmacovigilance study was designed that included 200 patient with allergic rhinoconjunctivitis and/or allergic asthma sensitised to mites (Dermatophagoides pteronyssinu and/or farinae). The dose increment period was carried out using a cluster schedule, where the optimal dose wa reached after 4 visits, administering two doses in each visit. The duration of the study was 5 months and a total o 1902 doses were administered. At the end of the trial, 31 adverse reactions in 23 patients were recorded. Six of these were systemic (0.3% of t administered doses) recorded in 6 patients (3% of the sample). One was an immediate reaction (grade 1) and delayed (4 mild and 1 moderate). Two were asthmatic exacerbations, 2 cutaneous reactions, 1 rhinitis and 1 an unspecific symptom (not IgE-mediated). Two appeared upon administration of the first vial and the remaining 4 after administration of the third cluster. Therefore, the schedule tested presents an adequate tolerance profile, suggesting savings (compared to th conventional schedule of 13 doses per patient) of 1800 visits and 1000 treatment doses in the whole study.

In vitro diagnosis of anaphylaxis.

The application and development of new in vitro techniques aims to enable a diagnosis to be reached while incurring no risk for the patient, a situation which is particularly desirable in the case of severe reactions like anaphylaxis. The in vitro diagnosis of anaphylaxis includes, among other aspects, the serial measurement of mediators which are released in the course of an anaphylactic reaction such as tryptase, histamine, chymase, carboxypeptidase A3, platelet-activating factor and other products from mastocytes. The detection of agents which trigger the anaphylactic reaction can be made with the use of serologic methods: serum-specific IgE or with cellular tests which measure the release of basophil mediators (leukotrienes, histamine) or with the analysis of the expression of basophil markers, a technique known as the basophil activation test. These techniques offer interesting alternatives in the diagnosis of anaphylaxis. The basophil activation test provides important advantages in patients with anaphylaxis to beta-lactams, non-steroidal anti-inflammatory drugs, neuromuscular blocking agents and drugs where there is no technique to measure specific IgE.

Immunotherapy with standardized extract of Dermatophagoides pteronyssinus in bronchial asthma: a dose-titration study.

According to the maximum tolerated dose (MTD) achieved, we assessed the changes in clinical and laboratory parameters, induced by specific immunotherapy (SIT), in a group of 43 asthmatic patients sensitized to Dermatophagoides pteronyssinus, over a period of 18 months. A standardized extract (100 Bu/ml; 40 micrograms/ml of Der p 1; 20 micrograms/ml of Der p 2) was used. The patients were divided into two groups: the high-dose immunotherapy (HDI) group (MTD > or = 4 micrograms Der p I) and the conventional immunotherapy (CI) group (MTD < 4 micrograms Der p 1). Changes in clinical severity index, medication, and symptom scores; in cutaneous and conjunctival reactivity; and in the levels of specific IgE, IgG, IgG1, and IgG4 to D. pteronyssinus (Der p 1 and Der p 2) were measured (ELISA monoclonal antibodies). Safety was monitored according to the EAACI guidelines. The range of the MTD was 0.8-16 micrograms of Der p 1. Ninety percent of the patients tolerated a dose of 3.2 micrograms, but only 18% of the patients reached a maintenance dose of 16 micrograms. The medians of the accumulated dose were 197 micrograms of Der p 1 for the HDI group, and 50 micrograms for the CI group. Conjunctival and cutaneous reactivity was significantly lowered (P < 0.001) after SIT, as were the clinical severity score and medication score in both groups, without significant differences between the groups, except for cutaneous reactivity. Levels of specific IgE decreased significantly (P < 0.01) in both groups, again without significant differences between the groups. The range of the increase in medians of specific IgG, IgG1, and IgG4 was 4.4-120-fold for the HDI group and 3-24-fold for the CI group (P < 0.01). The increase in the levels of Der p 1 and Der p 2 IgG4 were correlated to the changes in cutaneous and conjunctival reactivity (P < 0.01). These results show that a maintenance dose of 3.2 micrograms Der p 1 (8 BU) can induce pronounced clinical and immunologic changes with an excellent safety profile.