Gal d 1 特异性 IgE 可预测芬兰儿童对加热鸡蛋的过敏反应。

Gal d 1-specific IgE predicts allergy to heated egg in Finnish children.

机构信息

Skin and Allergy Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.

出版信息

Pediatr Allergy Immunol. 2018 Sep;29(6):637-643. doi: 10.1111/pai.12954.

DOI:10.1111/pai.12954

PMID:29974523

Abstract

BACKGROUND

Allergen-specific IgE levels can be useful in predicting outcomes of oral food challenges, but optimal cutoff levels vary in different populations. The aim was to determine cutoff values for egg white- and Gal d 1-, Gal d 2-, Gal d 3-, and Gal d 4-specific IgE (sIgE) predicting positive oral heated egg challenges in 185 Finnish children and adolescents.

METHODS

A total of 185 egg-sensitized patients (age: 1-19 years, median: 6.3, mean: 7.0 years) with suspected egg allergy underwent double-blind, placebo-controlled (n = 78), or open (n = 107) oral food challenges with heated egg white. Specific IgE levels to egg white, Gal d 1 (ovomucoid), Gal d 2 (ovalbumin), Gal d 3 (conalbumin), and Gal d 4 (lysozyme) were measured by ImmunoCAP and compared with challenge outcomes.

RESULTS

Of the 185 challenges, 124 (67%) were positive. Gal d 1 sIgE levels were significantly higher in the challenge-positive (median 13.5 kU/L, mean 33.2 kU/L) than in the challenge-negative group (median 0.2 kU/L, mean 1.2 kU/L), P < 0.0001. The diagnostic capacity of sIgE to egg white and Gal d 2, 3, and 4 was clearly weaker. In ROC analysis, the AUC for egg white was 0.86, Gal d 2 0.84, Gal d 3 0.79, and Gal d 4 0.77. Sensitization to Gal d 1 with a cutoff of value of >3.7 kU/L predicted a positive challenge with a specificity of 95% and sensitivity of 78%. The likelihood ratio was 15.9. In ROC analysis, the area under the curve was 0.94 (95% CI, 0.91-0.97). With a cutoff value of >14 kU/L, all challenges were positive, and with a cutoff of <0.9 kU/L, 95% of the challenges were negative. In the children aged 1-5 years (n = 88), the cutoff for Gal d 1 was >3.8 kU/L, and in the children above 6 years of age (n = 97), it was >3.5 kU/L.

CONCLUSION

Gal d 1-specific IgE is useful in distinguishing egg-sensitized patients with clinically reactive egg allergy from those tolerant of heated egg. The optimal cutoff point in a Finnish population of 185 children and adolescents was 3.7 kU/L with no significant difference between the younger and older age groups.

摘要

背景

特异性 IgE 水平可用于预测口服食物挑战的结果，但不同人群的最佳截断值不同。本研究旨在确定预测 185 名芬兰儿童和青少年阳性口服加热蛋清挑战的蛋清特异性 IgE（sIgE）和 Gal d 1、Gal d 2、Gal d 3 和 Gal d 4 特异性 IgE 的截断值。

方法

共 185 名蛋清致敏患者（年龄 1-19 岁，中位数 6.3 岁，平均 7.0 岁）因疑似鸡蛋过敏接受双盲、安慰剂对照（n=78）或开放（n=107）口服加热蛋清食物挑战。通过 ImmunoCAP 测量蛋清、Gal d 1（卵粘蛋白）、Gal d 2（卵白蛋白）、Gal d 3（伴白蛋白）和 Gal d 4（溶菌酶）的 sIgE 水平，并与挑战结果进行比较。

结果

在 185 次挑战中，有 124 次（67%）为阳性。阳性挑战组（中位数 13.5 kU/L，平均 33.2 kU/L）Gal d 1 sIgE 水平明显高于阴性挑战组（中位数 0.2 kU/L，平均 1.2 kU/L），P<0.0001。蛋清和 Gal d 2、3、4 的 sIgE 诊断能力明显较弱。ROC 分析中，蛋清的 AUC 为 0.86，Gal d 2 为 0.84，Gal d 3 为 0.79，Gal d 4 为 0.77。Gal d 1 致敏的截断值>3.7 kU/L 预测阳性挑战的特异性为 95%，敏感性为 78%。优势比为 15.9。ROC 分析中，曲线下面积为 0.94（95%CI，0.91-0.97）。截断值>14 kU/L 时，所有挑战均为阳性，截断值<0.9 kU/L 时，95%的挑战均为阴性。在 1-5 岁的儿童中（n=88），Gal d 1 的截断值为>3.8 kU/L，在 6 岁以上的儿童中（n=97），截断值为>3.5 kU/L。