Purpose

High serum immunoglobulin (Ig) E levels are associated with allergies, parasitic infections, and some immune deficiencies; however, the potential effects and clinical implications of low IgE levels on the human immune system are not well-known. This study aims to determine the disorders accompanying very low IgE levels in children and adults.

Methods

The patients whose IgE levels were determined between January 2015 and September 2020 were analyzed, and the patients with an IgE level < 2 IU/mL were included in this study. Demographic data, immunoglobulin levels, autoantibody results, and the diagnoses of the patients were noted from the electronic recording system of the hospital.

Result

The IgE levels were measured in 34,809 patients (21,875 children, 12,934 adults), and 130 patients had IgE levels < 2 IU/mL. Fifty-seven patients were children (0.26%); 73 were adults (0.56%). There was a malignant disease in 34 (9 of them children) (26%), autoimmune diseases in 20 (3 of them children) (15.4%), and immunodeficiency in 17 (14 of them children) (13.1%) of the patients. The most common reasons were other diseases, immunodeficiency and malignancy in children, and malignancy, autoimmune disorders, and other diseases in the adults, in rank order. The IgE level did not show any correlation with the levels of other immunoglobulins.

Conclusion

Although rare, a low IgE level has been shown to accompany malignancies, autoimmune disorders, and immune deficiencies. Patients with very low IgE levels should be carefully monitored for systemic disorders.

中文翻译：

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血清免疫球蛋白 E 水平极低是否有临床意义？

目的

高血清免疫球蛋白 (Ig) E 水平与过敏、寄生虫感染和一些免疫缺陷有关；然而，低 IgE 水平对人体免疫系统的潜在影响和临床意义尚不为人所知。本研究旨在确定伴随儿童和成人 IgE 水平极低的疾病。

方法

对 2015 年 1 月至 2020 年 9 月间 IgE 水平测定的患者进行分析，将 IgE 水平 < 2 IU/mL 的患者纳入本研究。从医院的电子记录系统记录人口学数据、免疫球蛋白水平、自身抗体结果和患者的诊断。

结果

测量了 34,809 名患者（21,875 名儿童，12,934 名成人）的 IgE 水平，其中 130 名患者的 IgE 水平 < 2 IU/mL。57 名患者是儿童（0.26%）；73 人是成年人（0.56%）。恶性疾病 34 人（其中儿童 9 人）（26%），自身免疫性疾病 20 人（其中儿童 3 人）（15.4%），免疫缺陷 17 人（其中儿童 14 人）（13.1%） . 最常见的原因是儿童的其他疾病、免疫缺陷和恶性肿瘤，以及成人的恶性肿瘤、自身免疫性疾病和其他疾病，按顺序排列。IgE 水平与其他免疫球蛋白水平没有任何相关性。

结论

虽然罕见，但已显示低 IgE 水平伴随着恶性肿瘤、自身免疫性疾病和免疫缺陷。应仔细监测 IgE 水平非常低的患者的全身性疾病。