Asero R, Conte M, Senna G E
Ambulatorio di Allergologia, Clinica San Carlo, Paderno Dugnano (MI), Italy.
Eur Ann Allergy Clin Immunol. 2012 Jun;44(3):107-12.
Extra-European immigrants are increasingly seen in allergy clinics. In view of their different genetic background they represent an opportunity to investigate the dynamics of sensitization to airborne allergens.
We investigated the pattern of airborne sensitization among allergic extra-European immigrants living in two areas of northern Italy.
Extra-European immigrants living in Milan and Verona were compared with age- and sex-matched or allergen-matched allergic Italians. Based on number of sensitizations to airborne allergens, patients and controls were divided into mono-/oligo-sensitized or multi-sensitized (1-3 or > 3, respectively).
In Milan grass pollen allergy was more frequent among immigrants than in controls (75% vs 49%; p < 0.01), whereas ragweed allergy prevailed among Italians (56% vs 20%; p < 0.001). In Verona, immigrants were rarely multi-sensitized (21% vs 43%; p < 0.01), more frequently sensitized to grass and birch. In both areas immigrants became allergic at a significantly older age than Italian controls (p < 0.0001), particularly to grass and mites. Allergy to HDM and ragweed was rare in Central & South Americans, whereas Africans showed the lowest proportion of multi-sensitizations. On average, immigrants became allergic after 2-4 years of stay in Italy.
Subjects genetically prone to become allergic to a particular allergen get eventually sensitized irrespective of their age when they are exposed to the "right" allergen for a sufficiently long time. The higher proportion of mono-/oligo-sensitized immigrants might reflect a shorter exposure to airborne allergen load in this group.
在过敏诊所中，来自欧洲以外地区的移民越来越常见。鉴于他们不同的遗传背景，他们为研究对空气传播过敏原的致敏动态提供了一个机会。
我们调查了居住在意大利北部两个地区的欧洲以外过敏移民对空气传播过敏原的致敏模式。
将居住在米兰和维罗纳的欧洲以外移民与年龄和性别匹配或过敏原匹配的意大利过敏患者进行比较。根据对空气传播过敏原的致敏数量，将患者和对照分为单/寡致敏或多致敏（分别为1 - 3种或超过3种）。
在米兰，移民中草花粉过敏比对照组更常见（75%对49%；p < 0.01），而豚草过敏在意大利人中更普遍（56%对20%；p < 0.001）。在维罗纳，移民很少有多致敏情况（21%对43%；p < 0.01），对草和桦树的致敏更频繁。在这两个地区，移民发生过敏的年龄显著大于意大利对照组（p < 0.0001），尤其是对草和螨虫。中南美洲人对屋尘螨和豚草过敏很少见，而非洲人多致敏的比例最低。平均而言，移民在意大利居住2 - 4年后发生过敏。
从遗传学角度易于对特定过敏原过敏的个体，在接触“合适”过敏原足够长时间后，无论其年龄大小最终都会致敏。单/寡致敏移民比例较高可能反映出该群体接触空气传播过敏原负荷的时间较短。
