Ebo D G, Bridts C H, Hagendorens M M, De Clerck L S, Stevens W J
Departement Immunologie, Allergologie en Reumatologie Universiteit Antwerpen Universiteitsplein 1, B 2610 Antwerpen, België.
Acta Clin Belg. 2003 May-Jun;58(3):183-9. doi: 10.1179/acb.2003.58.3.006.
It is well recognised that natural rubber latex allergy can be associated with serological cross-reactivity to plant allergens, especially tropical fruits and Ficus. In contrast, data on the frequency and clinical value of specific IgE antibodies against these allergens remain rare. In addition, little is known about the prevalence and diagnostic value of specific IgE antibodies to classical inhalant and animal allergens in NRL allergic patients.
The purpose of this study was to investigate the prevalence, the sensitivity, and the specificity of these different specific IgE antibodies in patients suffering from NRL allergy.
Serum samples of 42 NRL allergic adults were investigated. All had a history of NRL allergy confirmed by a positive skin test for latex and a positive latex-specific IgE. Samples were analysed for IgE antibodies against 9 plant food allergens (avocado, banana, chestnut, fig, kiwi, papaya, peanut, pineapple and tomato) and Ficus benjamina. A specific IgE quantification for 3 animal food allergens (codfish, cow's milk, egg's white) and 8 common inhalant allergens (Dermatophagoïdes pteronyssinus, birch pollen, timothy grass pollen, mugwort pollen, cat and dog epithelium, Aspergillus fumigatus and Cladosporium herbarum) was also performed. Because double blind placebo-controlled challenges could not be considered, for ethical reasons, patient's food allergy or immediate hypersensitivity for Ficus and inhalant allergens was documented by a standardised questionnaire. Diagnosis of atopy was based on a relevant history and the presence of a specific IgE antibody to at least one classical inhalant allergen. For some IgE determinations presence or absence of cross-reactivity was investigated by CAP-inhibition tests.
A specific IgE antibody to at least one of the investigated inhalant and animal food allergens was found in respectively 76% and 12% of the serum samples. A plant food-specific IgE antibody was observed in 88% of the serum samples, most frequently to papaya (71%) and least frequently to kiwi (17%). Twenty-nine percent of the serum samples contained Ficus-IgE. According to the questionnaire and the threshold of 0.35 kUa/L, sensitivity of the plant food IgE antibodies varied between 0% for papaya and 73% for avocado. Specificity varied between 28% for papaya and 91% for kiwi. For Ficus-IgE sensitivity was 20% and specificity 70%.
For inhalant and animal food allergens sensitivity and specificity of the IgE quantification correlated generally well with the values obtained in non-NRL allergic adults. Determination of specific IgE to the investigated plant foods and Ficus was not always a sensitive neither a specific test to establish the clinical diagnosis of this allergy.
众所周知，天然橡胶乳胶过敏可能与对植物过敏原，尤其是热带水果和榕属植物的血清学交叉反应有关。相比之下，针对这些过敏原的特异性IgE抗体的频率和临床价值的数据仍然很少。此外，对于天然橡胶乳胶过敏患者中针对经典吸入性和动物过敏原的特异性IgE抗体的患病率和诊断价值知之甚少。
本研究的目的是调查这些不同特异性IgE抗体在天然橡胶乳胶过敏患者中的患病率、敏感性和特异性。
对42名天然橡胶乳胶过敏的成年人的血清样本进行了调查。所有人都有天然橡胶乳胶过敏史，经乳胶皮肤试验阳性和乳胶特异性IgE阳性证实。对样本进行了针对9种植物性食物过敏原（鳄梨、香蕉、栗子、无花果、猕猴桃、木瓜、花生、菠萝和番茄）和垂叶榕的IgE抗体分析。还对3种动物性食物过敏原（鳕鱼、牛奶、蛋清）和8种常见吸入性过敏原（屋尘螨、桦树花粉、梯牧草花粉、艾蒿花粉、猫和狗上皮、烟曲霉和枝孢霉）进行了特异性IgE定量检测。由于出于伦理原因无法进行双盲安慰剂对照激发试验，因此通过标准化问卷记录了患者对榕属植物和吸入性过敏原的食物过敏或速发型超敏反应。特应性的诊断基于相关病史以及存在针对至少一种经典吸入性过敏原的特异性IgE抗体。对于一些IgE测定，通过CAP抑制试验研究交叉反应的存在与否。
分别在76%和12%的血清样本中发现了针对至少一种所研究的吸入性和动物性食物过敏原的特异性IgE抗体。在88%的血清样本中观察到了植物性食物特异性IgE抗体，最常见于木瓜（71%），最不常见于猕猴桃（17%）。29%的血清样本含有榕属植物IgE。根据问卷和0.35 kUa/L的阈值，植物性食物IgE抗体的敏感性在木瓜为0%至鳄梨为73%之间变化。特异性在木瓜为28%至猕猴桃为91%之间变化。对于榕属植物IgE，敏感性为%，特异性为70%。
对于吸入性和动物性食物过敏原，IgE定量检测的敏感性和特异性通常与非天然橡胶乳胶过敏成年人中获得的值相关性良好。测定所研究的植物性食物和榕属植物的特异性IgE并不总是一种敏感或特异的试验来确立这种过敏的临床诊断。
