食物特异性IgG4在并发胃肠道症状的食物过敏性湿疹患儿诊断中的作用

Application of Food-Specific IgG4 in Diagnosing Food Allergy in Childhood Eczema with Gastrointestinal Symptom

目的探讨食物特异性IgG4检测在诊断并发胃肠道症状的食物过敏性湿疹患儿的应用价值。方法采用酶联免疫吸附法（ELISA）对84例食物特异性IgE筛查阴性的湿疹和慢性荨麻疹患儿行食物特异性IgG4检测。结果84例患儿中，IgG4阳性75例（89．29％），1～4种过敏原及≥5种过敏原阳性者分别为17例、22例、13例、7例和16例。主要食物过敏原是牛奶和鸡蛋，≤2岁和〉2岁患儿IgG4阳性率分别为90．00％（36／40）和88．63％（39／44），14种食物特异性IgG4的阳性率两者差异无统计学意义（P〉0．05）。湿疹并发胃肠道症状组IgG4阳性率明显高于湿疹无胃肠道症状组、荨麻疹组和正常儿童组。蟹、牛奶、大麦、大豆、西红柿的特异性IgG4的阳性率在各组间比较差异有统计学意义（P〈0．05）。结论并发胃肠道症状的湿疹患儿，检测其食物特异性IgG4对其病因诊断及指导治疗具有一定意义。

Objective To evaluate the usefulness of food-specific IgG4 in diagnosis of food allergy in childhood eczema with gastrointestinal symptom. Methods Food-specific IgG4 test was carried out in 84 childhood eczema and chronic urticaria, but food-specific IgE negative. Results 75 （89. 29% ） of patients were food-specific IgG4 positive. The numbers of subjects who were allergic to 1 or simultaneously allergic to 2 - 4 and more than five allergens were 17, 22, 13, 7,16 cases, respectively. Milk and egg were the major food allergens. The IgG4 positive rates in children aged ≤2 years and 〉2 years were 90. 00% （36/40）and 88. 63% （39/44） , respectively. The positive rates of food-specific IgG4 for 14 foods were no significant differences between ≤ 2 years old and 〉 2 years old children. The positive rates of IgG4 were higher in patients with gastrointestinal symptom than those without gastrointestinal symptom, urticaria alone and normal controls. The positive rates of food-specific IgG4 for crab, milk, barley, bean and tomato were significant higher in the childhood eczema with gastrointestinal symptom than the others. Conclusion Measurement of food-specific IgG 4 is important for the diagnosis and the treatment of childhood eczema with gastrointestinal symptom.