Introduction
IgA deficiency is one of the commonest primary antibody deficiencies. Although many affected individuals could be asymptomatic, selected patients suffer from recurrent mucosal infections, allergies, and autoimmune diseases. Aim of the study: To investigate the prevalence of IgA deficiency among Egyptian patients with food allergy.

Material and methods
We studied 100 patients (62 males, 38 females; mean age, 28.6 years) with multiple food allergies who were recruited on the basis of adequate immunological assessment by history, skin prick test, and confirmed by open challenge test as well as 50 healthy controls. Measurement of levels of IgE and IgA using ELISA technique were performed for all patients and controls.

Results
Deficiency of IgA was detected in 67% of patients with food allergy. Serum IgA levels were significantly lower among patients with food allergy (67.3 µg/ml; range, 56.7-72.0 µg/ml) as compared to healthy control (78.6 µg/ml; range, 72.8-84 µg/ml). Both IgA and IgE levels were not statistically different between patients with food allergy only and those with combined food and aeroallergen. Among food allergic group, serum IgA levels were inversely correlated with serum IgE levels (r = –0.314, p < 0.001).

Conclusions
Manifestations of atopy, such as food allergy might be a present feature before diagnosis of primary immune deficiency diseases as IgA deficiency.



中文翻译：

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埃及食物过敏患者选择性免疫球蛋白 A 缺乏症的研究

引言
IgA 缺乏症是最常见的一抗缺乏症之一。尽管许多受影响的个体可能没有症状，但选定的患者患有复发性粘膜感染、过敏和自身免疫性疾病。研究目的：调查埃及食物过敏患者中 IgA 缺乏症的患病率。

材料和方法
我们研究了 100 名患有多种食物过敏的患者（62 名男性，38 名女性；平均年龄 28.6 岁），这些患者是在通过病史、皮肤点刺试验进行充分免疫评估并通过开放激发试验以及50 个健康对照。使用 ELISA 技术测量所有患者和对照的 IgE 和 IgA 水平。

结果
在 67% 的食物过敏患者中检测到 IgA 缺乏。与健康对照组（78.6 µg/ml；范围 72.8-84 µg/ml）相比，食物过敏患者的血清 IgA 水平显着降低（67.3 µg/ml；范围 56.7-72.0 µg/ml）。IgA 和 IgE 水平在仅对食物过敏的患者与同时使用食物和气源性过敏原的患者之间没有统计学差异。在食物过敏组中，血清 IgA 水平与血清​​ IgE 水平呈负相关（r = - 0.314，p < 0.001）。

结论
在将原发性免疫缺陷疾病诊断为 IgA 缺乏症之前，特应性的表现，例如食物过敏可能是一个存在的特征。