Age at symptom onset and distribution by sex and symptoms in patients sensitized to different allergens

The aim of our study was to analyze the clinical features, particularly the age at symptom onset, of allergic subjects (asthma and/or rhinitis) on the basis of the etiologic elements (sensitization to various allergens). We identified a group of monosensitized patients and a group of polysensitized patients. Within these groups, we identified subgroups of subjects monosensitized to one of the five main allergenic mixes (mites, Gramineae, trees, Parietaria, and Artemisia) and five subgroups of patients sensitized nonexclusively, that is, polysensitized, to the same allergens. The comparison between the two groups and among the various subgroups enabled us to conclude that:

• 1)

  mono- and polysensitized patients present some clinical features so different as to constitute two clearly distinct clinical groups
• 2)

  analysis of the clinical features associated with the sensitization to a specific allergen brings us to significantly different conclusions when we consider subgroups of monosensitized or polysensitized patients
• 3)

  the parameter "age at symptom onset" shows great heterogeneity among both the mono- and the polysensitized subgroups - in particular, the great differences in mean age among the monosensitized subgroups (trees>y4rtemi.s(fl>Pflrie/flria>Gramineae>mites) appear very interesting and are open to various interpretative hypotheses
• 4)

  unlike the polysensitized group, in the monosensitized group and subgroups, mean age is similar between men and women and, only for tree- and parietaria -monosensitive patients, also between asthmatic and rhinitic subjects.

     

Basophil activation during pollen season in patients monosensitized to grass pollens

BACKGROUND: Basotest is a new basophil-activation test based upon the expression of CD63 (gp53) in the presence of allergens. It is an effective diagnostic test for pollen-allergic patients. However, it is not known whether Basotest results differ during the pollen season. METHODS: We examined the activation of basophils by Basotest in 13 patients sensitized only to grass pollen, before and during the pollen season, in order to assess whether Basotest could be used as a diagnostic test during the pollen season. Dose-response curves with 10-fold increasing concentrations of timothy grass pollen (10-4 to 100 AU) were carried out. RESULTS: Basophils were not activated spontaneously during the pollen season since the CD63 expression was below detectable levels before in vitro cell activation. A decreased percentage of activated basophils at the peak of activation was found in comparing the pre- and in-season tests, but all patients had a positive test. When basophil activation was at its peak, the allergen concentration was similar during the two periods. Moreover, the median area under the curve was significantly (P < 0.02) reduced during the season as compared to before the season. CONCLUSION: Basotest can therefore be used as a diagnostic test during the pollen season, but the allergen exposure needs to be characterized if quantitative studies are performed.     

Multiple-allergen and single-allergen immunotherapy strategies in polysensitized patients: looking at the published evidence

In allergen immunotherapy there is debate as to whether polysensitized patients are best treated with many allergens simultaneously (chosen according to the sensitization profile, a predominantly North American approach) or a single allergen (chosen according to the most clinically problematic allergy, a predominantly European approach). In patients seeking treatment for moderate-to-severe respiratory allergies, polysensitization is more prevalent (range, 50% to 80%) than monosensitization in both the United States and Europe. Safe, effective, single-allergen preparations will most likely have been tested in polysensitized patients. In robust, large-scale clinical trials of grass pollen sublingual tablets, polysensitized patients benefited at least as much from allergen immunotherapy as monosensitized patients. A recent review of multiallergen immunotherapy concluded that simultaneous delivery of multiple unrelated allergens can be clinically effective but that there was a need for additional investigation of therapy with more than 2 allergen extracts (particularly in sublingual allergen immunotherapy). More work is also required to determine whether single-allergen and multiallergen immunotherapy protocols elicit distinct immune responses in monosensitized and polysensitized patients. Sublingual and subcutaneous multiallergen immunotherapy in polysensitized patients requires more supporting data to validate its efficacy in practice.     

Coincidence of atopy profile in terms of monosensitization and polysensitization in children and their parents

BACKGROUND: Results from epidemiologic studies have shown that childhood atopy is probably a hereditary disorder, because the offspring of affected parents have a higher risk of developing atopy. Among the atopic population, some subjects are sensitized to only one class of allergens (monosensitized), while other subjects are sensitized to more than one class of allergens (polysensitized). The aim of this study was to investigate whether atopy profile (monosensitization/polysensitization) in children is linked to the same conditions in their parents. METHODS: We evaluated sensitization to five classes of aeroallergens (house dust mites, animal danders, pollens, molds, and cockroach) by skin prick testing in a group of 494 children with suspicious allergic symptoms and in their parents. RESULTS: The frequency of parental atopy was highest (51.6%) in polysensitized children (n = 189), intermediate (37.1%) in monosensitized children (n = 178), and was lowest (22.4%) in nonsensitized children (n = 127). The proportion of polysensitized subjects among atopic parents was significantly higher for polysensitized children (45.6%) than for monosensitized children (31.1%). Polysensitized children were found to more frequently have one or both parents polysensitized (32.3%, 7.4%) than monosensitized children (18.5%, 2.2%) with odds ratios of 2.09 (95% CI: 1.29-3.40) and 3.48 (1.12-10.78), respectively, whereas the likelihood of having one or two monosensitized parents was not increased for polysensitized children. CONCLUSION: Our data suggest a familial coincidence of atopy profile in terms of monosensitization and polysensitization, although the relative importance of genetic or environmental influence should be studied further.     

The most common phenotypes of sensitization to inhalant allergens in childhood

Background Atopic individuals are frequently sensitized to a limited number of certain allergens, although most of them are exposed to multiple inhalant allergens in daily life. Objective We investigated the hypothesis that observed common patterns of sensitization might occur with similar frequency within two independent study populations of school-children. Methods The results were derived from skin-prick tests conducted on two large samples of children (study 1:n= 583; study 2: n= 1099) examined with the same panel of six inhalant allergens. Results In order to ensure that the comparison was uniform, the younger subpopulation of study 1 (n= 147) was compared with the sample of study 2 (n= 374). The highest frequency for monosensitization was found for sensitization to Dermatophagoides pteronyssinus (study 1: 18.4%, study 2: 20.3%), followed by monosensitization to grass pollens (study 1: 12.2%; study 2: 8.8%). Using multiple logistic regression for each specific sensitization, a significantly increased relative risk of sensitization to hazel pollens (study 1 OR 5.9; study 2 OR: 24.3) appeared to be associated with sensitization to birch pollens. The same applied to dog dander (study 1 OR: 7.3; study 2 OR: 2.6), which showed an association with sensitization to cat dander. Conclusion In summary, our data suggest that certain clusters of monosensitization and polysensitization to common inhalant allergens exist among a given population. This may well be a reflection of diversity in disposition to specific sensitization and/or antigen crossreactivity. From a practical point of view the data also might help in counselling parents of allergic children.     

Ⅰ型过敏患者血清白细胞介素-22水平与变应原关系的研究

目的研究单一致敏和多重致敏、吸入性变应原和食入性变应原引起的Ⅰ型超敏反应疾病患者血清白细胞介素(IL)-22水平,探索IL-22水平与变应原的关系。方法以100例Ⅰ型超敏反应疾病患者和30例健康对照者为研究对象,免疫印迹法检测血清中19种变应原特异性IgE抗体,酶联免疫吸附试验(ELISA)检测血清IL-22水平。结果患者血清IL-22水平与致敏变应原数量呈正相关(r=0.318,P=0.001)。多重致敏患者、单一致敏患者、健康对照者血清IL-22水平分别为24.52(20.41,29.27)、22.02(15.25,25.59)、18.06(16.02,23.04)pg/mL,多重致敏患者(n=42)明显高于单一致敏患者(n=58)和健康对照(U=867.500和229.000,P0.05),单一致敏患者高于健康对照者(U=608.000,P0.05),差异均有统计学意义,但是吸入性变应原和食入性变应原致敏患者(n=34和n=24)之间IL-22水平比较,差异无统计学意义(t=0.082,P0.05)。结论Ⅰ型超敏反应疾病患者血清IL-22水平升高,并与致敏的变应原数量呈正相关。