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.

Can component-based microarray replace fluorescent enzimoimmunoassay in the diagnosis of grass and cypress pollen allergy?

BACKGROUND: Few data on the diagnostic accuracy in pollinosis of the microarray ISAC of allergens are available. OBJECTIVE: We aim to comparatively analyse ISAC CRD103 with the whole-extract ImmunoCAP in grass and cypress pollen allergy, evaluating the suitability of the manufacturer's recommended cut-off points for both techniques. METHODS: We studied 120 atopic patients grouped into grass and cypress pollen-allergic patients and controls based on clinical history and skin prick tests. Specific IgE against Phleum pratense and Cupressus arizonica by ImmunoCAP and ISAC CRD103 were performed on all subjects. RESULTS: In the grass pollen group (43 allergic/26 controls), both microarray and CAP showed high sensitivity (Se) and specificity (Sp) values (ISAC: Se 97.7, Sp 92.3; CAP: Se 95.3, Sp 96.1) for recommended cut-off points. Comparing the optimal (ISAC: 0.4 ISU; CAP: 0.33 kU/L) with the recommended cut-off points within the same technique, diagnostic agreement was observed in both techniques. Thus, CAP and ISAC showed similar diagnostic performance in grass pollen allergy when using recommended cut-off points. In cypress pollen group (12 allergic/92 controls), the microarray (Se: 91.7, Sp 91.3) showed similar Se but significantly higher Sp (P=0.034) than CAP (Se: 91.7, Sp: 80.4) using recommended cut-off points. However, although diagnostic performance of the microarray did not change when comparing the optimal (0.82 ISU) with the recommended cut-off point, CAP improved diagnosis of cypress pollen allergy, when applying the optimal (0.66 kU/L)(CAP Se: 91.7, Sp: 89.1) instead of the manufacturer's recommended cut-off point. Thus, when the most suitable cut-off point for both techniques (ISAC: 0.3 ISU; CAP: 0.66 kU/L) is selected, microarray and CAP provide equivalent diagnoses. CONCLUSIONS AND CLINICAL RELEVANCE: Component-based microarray ISAC CRD103 and whole-allergen CAP showed high Se and Sp diagnosing equally grass and cypress pollen allergy. The cut-off point for each allergen should be properly applied for both techniques.

Allergenicity and cross-reactivity of pine pollen.

BACKGROUND: Pine pollen has long been considered a non-allergenic pollen. The large size of the grain and its low levels of proteins are the main reasons invoked to explain this low allergenicity. The aim of this study was to describe the main allergenic bands of Pinus radiata (PR) and its cross-reactivity with other pine species, other conifers and grass pollen. METHODS: Sixty-five pine-pollen-allergic patients (51% also sensitized to grass pollen) were studied. Skin prick tests (SPT) to a battery of allergens including PR, Pinus pinea, Pinus sylvestris, Pinus nigra and Cupressus sempervirens pollens and specific IgE determination to PR and Pinus strobus were performed. IgE-immunoblotting to a PR extract and other pine pollens was also carried out. UniCAP inhibition and immunoblotting inhibition studies were performed to assess the cross-reactivity between different pollens. RESULTS: The SPTs were positive with all the pine pollen extracts tested in 69% of the patients. Specific IgE was positive to PR or P. strobus in 77% of the patients, and to Lolium perenne in 51%. Nine different allergenic bands were detected. The two main allergens were a 42 kDa band recognized by 85% of the patients and a band of approximately 6-8 kDa recognized by 40%. A high degree of cross-reactivity was observed between different pine pollen species, but not between pines and C. sempervirens pollen. A partial cross-reactivity could be seen between pine and grass pollens only in patients also sensitized to L. perenne. CONCLUSIONS: Pine pollen should be considered as a potential allergenic pollen especially where this pollen is abundant. The detection of a high number of patients that were monosensitized to pine pollen suggests the possibility of treating these patients with specific immunotherapy.

Allergy to laxative compound (Plantago ovata seed) among health care professionals.

BACKGROUND: The seeds of Plantago ovata (psyllium, ispaghula) used in the manufacture of bulk laxatives are known to be the cause of occupational allergy (rhinitis, asthma) in health care and pharmaceutical workers. OBJECTIVE: We studied the prevalence of P ovata seed allergy among health care workers in geriatric care homes and compared it with a group of health care professionals not exposed to P ovata seed. Cross reactivity with Plantago lanceolata pollen was also studied. METHODS: Two groups of health professionals were recruited: 58 health care workers from geriatric care homes who were exposed daily to laxatives containing P ovata and 63 nonexposed health care professionals. The prevalence of allergy and sensitization to P ovata seed was determined based on clinical history, skin prick test, and analysis of specific immunoglobulin (Ig) E. IgE immunoblotting was performed to calculate the molecular weights of the P ovata seed allergens. Cross reactivity to P lanceolata pollen was studied by enzyme allergosorbent test (EAST) and immunoblot inhibition techniques. RESULTS: The prevalence of sensitization and clinical allergy to P ovata seed in the exposed group was 13.8% and 8.6%, respectively. No sensitization was observed in the nonexposed group. IgE-binding proteins of 17, 20, 25, 32-34, 54, 73-77, and > 97 kDa were identified. EAST inhibition and immunoblot inhibition demonstrated the existence of cross reactivity between P ovata seed and P lanceolata pollen extracts. CONCLUSIONS: The rate of sensitization to P ovata seed is high among health care workers in geriatric care homes (13.8%). A mild cross reactivity between P ovata seed and P lanceolata pollen was observed.

Alergia al polen de las oleáceas en un lugar donde no hay olivos / Oleaceae pollen allergy in a place where there’s no olive trees

Antecedentes y objetivos: El polen del fresno (Fraxinus excelsior), árbol perteneciente a la familia Oleaceae, se ha descrito recientemente como un alérgeno relevante en algunos países centroeuropeos. El objetivo de este trabajo es estudiar la importancia que este polen tiene como factor desencadenante de los síntomas alérgicos que sufren, al final del invierno y principio de la primavera, algunos pacientes que viven en País Vasco, donde no existen olivos pero el fresno es un árbol abundante. Métodos: Se seleccionaron 48 pacientes que se clasificaron en tres grupos en función de la sensibilización predominante: pacientes alérgicos a oleáceas (O), alérgicos a gramíneas (G) y alérgicos a ambos pólenes (M). Los pacientes se dividieron además en dos grupos en función de la época en la que tenían los síntomas: pacientes con síntomas tempranos o pacientes con síntomas tardíos. Se les realizó la prueba del prick con una batería de pólenes, pruebas de exposición conjuntival con extractos de polen de olivo y de fresno y la determinación de IgE específica (EAST) frente a varios pólenes. Resultados: En el grupo O, el 100% de los pacientes tuvo síntomas tempranos, esto es, coincidiendo con la floración del fresno y antes de aparecer el polen de las gramíneas. En los grupos M y G los porcentajes de pacientes con síntomas tempranos fueron del 40% y 16%, respectivamente. Las pruebas de provocación conjuntival con polen de olivo y fresno resultaron positivos en el 100% y 70%, respectivamente, de los pacientes del grupo O, en el 78% y 50% del grupo M y en el 58% y 31% del grupo G. Los pacientes con síntomas tempranos tuvieron con mayor frecuencia pruebas cutáneas positivas frente al polen de F. excelsior (p < 0,05) y unas concentraciones de IgE específica frente a F. excelsior significativamente mayores (p < 0,05) que los pacientes con síntomas tardíos. Las pruebas de provocación conjuntival con polen de O. europaea fueron de mayor intensidad en los pacientes con síntomas tempranos. Conclusión: Los pacientes que residen en País Vasco y sufren síntomas durante el final del invierno y el comienzo de la primavera tenían una sensibilización predominante al polen del fresno y del olivo, en comparación con los pacientes que únicamente tenían síntomas tardíos (en mayo y junio). El polen del fresno puede considerarse una posible causa de polinosis en aquellos lugares donde su presencia es frecuente

Background: Ash tree belongs to the Oleaceae family; it has been recently described as a relevant allergen in some countries. The aim of this study is to demonstrate the importance of the ash pollen as a triggering factor of the allergic symptoms showed in early spring by a group of patients who live in the Basque Country, where ash are common trees and olive trees are not present. Methods: In accordance with their predominantly sensitisation we selected and classified 48 pollen-allergic-patients in three groups: oleaceae allergic patients (O), grass allergic patients (G) and oleaceae + grass allergic patients (M). Patients were also divided in two groups depending on the season when they showed the symptoms: patients with early or late symptoms respectively. Skin prick tests (SPT) and specific IgE (EAST) to Olea, Fraxinus and Lolium, patient’s scores of symptoms and rescue medication between February and July 2000, and conjunctival challenge tests with ash and olive pollen extracts were performed. Results: 100% of O patients, 40% of M patients and 16% of G patients suffered from early symptoms, coinciding with the flowering of ash, when grass pollen is not present yet. Conjunctival challenge tests with ash and olive pollen extracts were positive in 70% and 100% respectively in O patients, 50% and 78% in M patients and 31% and 58% in G patients. Conjunctival challenge tests in patients who suffered from early symptoms with olive extract were positive with lower concentrations of the extract. The patients with early symptoms had a higher rate of positive SPT with ash pollen (p < 0,05) and had significant higher levels of specific IgE to F. excelsior pollen (p < 0,05) than late symptomatic patients. Conjunctival challenge test to O. europaea pollen produced more symptoms to patients with early symptoms. Conclusion: Patients living in the Basque Country and suffering from symptoms during early spring had a predominant sensitisation to ash and olive pollen compared to those patients showing only late symptoms. Ash pollen can be considered as a potentially cause of hay fever in these areas where it is present in considerable amounts

Systemic reactions to immunotherapy: influence of composition and manufacturer.

BACKGROUND: Although immunotherapy clearly demonstrated the benefit of reducing allergic symptoms, it has the drawback of adverse events, mainly systemic reactions that could be very inconvenient for patients and even life-threatening. OBJECTIVE: The aim of the present study was to assess the incidence of systemic reactions to immunotherapy in a large number of patients, and its potential relationship with the characteristics of therapy, such as allergen composition or manufacturing laboratory. METHODS: This study analysed the administration of specific immunotherapy during a period of 5 years, involving 1212 patients affected by respiratory hypersensitivity or hymenoptera venom anaphylaxis. Commercial extracts were supplied by five different laboratories. All the patients were attended at an out-clinic immunotherapy unit by the same experienced staff. Immunotherapy was given following a conventional schedule, modified according the usual recommendations. RESULTS: A total of 250 adverse reactions have been recorded, resulting in a frequency of 0.84% over the total number of injections. Seventy-nine of them (32%) were systemic reactions (0.27% SR/injection). The 79 systemic reactions were observed in 60 patients (5% of the patients). The frequency of systemic reactions was significantly lower (P < 0.01) on the group of mites than on the other groups. The frequency of systemic reactions varies according to the manufacturing laboratory. In the case of mite extracts, although one of the laboratories had a lower frequency of adverse systemic reactions, it did not reach the level of statistical significance. However, in relation to pollen extracts, preparations of one of the manufacturers had a significantly lower frequency of systemic reactions. Concerning the time of occurrence, 27% of systemic reactions were delayed, thus they appeared at least 30 min after the vaccine injection, most of them due to pollen extracts. CONCLUSION: This is a preliminary study to evaluate the factors that could facilitate the appearance of systemic reactions demonstrating that not only the composition but also the manufacturer is connected to systemic reactions. Although further studies are needed to clearly establish the influence of manufacturer on frequency and time of appearance of systemic reactions, it seems necessary to reach a wide consensus on allergen extract standardization methods.