Armentia Alicia, Lombardero Manuel, Martinez Camilo, Barber Domingo, Vega Jose Maria, Callejo Ana
Sección de Alergia, Hospital Rio Hortega, Valladolid, Spain.
J Asthma. 2004 Feb;41(1):99-107. doi: 10.1081/jas-120026067.
Workers occupationally exposed to grain dust have a high prevalence of asthma. The pathogenesis of their respiratory symptoms remains obscure when sensitization to cereal allergens has not been proved. Given the ubiquity of arthropods in stored vegetable products, we have studied the allergenic potential of two very prevalent grain pests, Eurygaster and Ephestia, as a cause of occupational asthma. We have also studied the allergenic relationship between Anisakis simplex (AS) and these pests.
We selected 15 asthmatic workers exposed to cereal dust, in whom sensitization to cereal allergens was not clear. As controls, we selected a patient who suffered from anaphylaxis after the ingestion of cereals, 6 patients sensitized to different arthropods, 1 patient who suffered from asthma after inhaling fish flour contaminated with AS, and a pool of 40 asthmatic patients with different ethiologies not due to arthropods or cereals. We performed prick tests with these pests, AS, and pure and parasitized flours, bronchial challenges, specific IgE determination, and RAST inhibition.
All of the 15 cereal-exposed workers were sensitized to Eurygaster and Ephestia. Only 2 had detectable levels of serum IgE to these pests, but 13 presented a positive prick test result and IgE to AS without problems after eating fish. Bronchial challenges were positive to Eurygaster in 7 patients and to Ephestia in 2 patients. Twelve patients had positive prick tests to parasitized flour but not to pure flour. The patient with cereal anaplylaxis presented sensitization to both flours but not to AS. In the control group, the patient who suffered from asthma after the inhalation of AS-parasitized fish flour presented a positive prick test result and high levels of specific IgE to these pests. The RAST inhibition showed cross-reactivity between Eurygaster and AS in this patient, but the inhibition was not as evident with the sera of other workers. The same tests in the group of 40 asthmatic patients were negative.
The clinical importance of pests as a cause of baker's asthma should not be underestimated. Sensitization to Eurygaster and Ephestia could be important in the asthma episodes suffered by our patients, and the parasitized wheat was found to have a higher allergenic potential than pure cereal flour.
职业性接触谷物粉尘的工人哮喘患病率很高。当尚未证实对谷物过敏原致敏时，其呼吸道症状的发病机制仍不清楚。鉴于节肢动物在储存的蔬菜产品中普遍存在，我们研究了两种非常常见的谷物害虫——麦蝽和粉斑螟蛾作为职业性哮喘病因的致敏潜力。我们还研究了简单异尖线虫（AS）与这些害虫之间的致敏关系。
我们选择了15名接触谷物粉尘的哮喘工人，他们对谷物过敏原的致敏情况不明确。作为对照，我们选择了一名摄入谷物后发生过敏反应的患者、6名对不同节肢动物致敏的患者、一名吸入被AS污染的鱼粉后患哮喘的患者，以及一组40名病因各异（非节肢动物或谷物所致）的哮喘患者。我们用这些害虫、AS、纯面粉和受寄生虫感染的面粉进行了点刺试验、支气管激发试验、特异性IgE测定和放射变应原吸附试验抑制。
15名接触谷物的工人均对麦蝽和粉斑螟蛾致敏。只有2人血清中可检测到针对这些害虫的IgE水平，但13人点刺试验结果为阳性，且食用鱼类后对AS的IgE检测无异常。7名患者对麦蝽的支气管激发试验呈阳性，2名患者对粉斑螟蛾的支气管激发试验呈阳性。12名患者对受寄生虫感染的面粉点刺试验呈阳性，但对纯面粉点刺试验呈阴性。谷物过敏反应患者对两种面粉均致敏，但对AS不致敏。在对照组中，吸入被AS寄生的鱼粉后患哮喘患者的点刺试验结果为阳性，且对这些害虫的特异性IgE水平较高。放射变应原吸附试验抑制显示该患者的麦蝽和AS之间存在交叉反应，但其他工人血清中的抑制作用不那么明显。40名哮喘患者组的相同试验均为阴性。
不应低估害虫作为面包师哮喘病因的临床重要性。对麦蝽和粉斑螟蛾致敏可能对我们的患者所患哮喘发作起重要作用，并且发现受寄生虫感染的小麦比纯谷物面粉具有更高的致敏潜力。
