北京协和医院桦树花粉变应原点刺液对桦树花粉过敏症的诊断价值

摘要

目的 通过皮肤点刺试验(skin prick test,SPT)评价北京协和医院桦树花粉变应原点刺液(简称协和桦树花粉变应原)诊断桦树花粉过敏症的有效性和安全性.方法 选取2015年8月10日至2016年10月20日在北京协和医院变态(过敏)反应科就诊,患有过敏性鼻炎、 过敏性哮喘、 过敏性结膜炎、 过敏性皮炎、 荨麻疹等过敏性疾病的门诊患者.对所有受试者进行协和桦树花粉变应原SPT,15 min后测定平均风团直径(mean wheal diameter,MWD).以桦树花粉血清特异性免疫球蛋白E(specific immunoglobulin E,sIgE)作为确认桦树花粉过敏症的诊断标准,进行受试者工作特征曲线(receiver operating characteristic curve,ROC曲线)分析,判断不同诊断界值下,协和桦树花粉变应原临床诊断桦树花粉过敏症的准确性;同时记录不良事件,评价协和桦树花粉变应原的安全性.结果 本研究共计入组1029例,无脱落病例.全分析集(full analysis set,FAS)1007例,平均年龄(32.14±13.69)岁.FAS的ROC曲线下面积(area under curve,AUC)为0.909(95%可信区间0.891~0.928).据FAS的ROC估算SPT诊断桦树花粉过敏的MWD最佳诊断界值为4.25 mm,特异度达95%时的MWD诊断界值为5.75 mm.分别以MWD 3.00、4.25和5.75 mm为诊断界值,协和桦树花粉变应原SPT诊断桦树花粉过敏的敏感度依次降低,分别为0.9061(95%可信区间0.8840~0.9282)、0.7973(95%可信区间0.7669~0.8277)、0.6706(95%可信区间0.6351~0.7062);而特异度依次升高,分别为0.6905(95%可信区间0.6410~0.7399)、0.9018(95%可信区间0.8700~0.9336)、0.9524(95%可信区间0.9296~0.9752).安全集(save set,SS)1029例,6例出现7次不良事件,不良事件发生率0.58%(6/1029),主要表现为SPT后鼻痒、 喷嚏、 流涕、 鼻塞、 眼痒以及点刺部位局部皮肤出现较大风团反应.所有受试者均未出现严重不良事件.结论 协和桦树花粉变应原对于桦树花粉过敏症具有良好的诊断价值,安全性好.结合病史和不同的SPT诊断界值,可以提高诊断的准确度.%Objective To evaluate the accuracy and safety of birch pollen extract which was used for skin prick test ( SPT) in the diagnosis of birch pollen allergy. Methods Patients with diagnosis of allergic conjunctivitis, allergic rhinitis, allergic asthma, allergic dermatitis, urticaria and other allergic diseases were collected from the Outpatients of Department of Allergy, Peking Union Medical College Hospital since August 10, 2015 to October 20, 2016. All patients were prescribed birch pollen SPT, and the mean wheal diameter ( MWD) was measured after 15 minutes. Receiver operating characteristic curve ( ROC) analysis was performed based on the results of specific immunoglobulin E ( sIgE) detec-tion. The accuracy of SPT in the diagnosis of birch pollen allergy was evaluated under different diagnostic cutoff values. Adverse events were also recorded to evaluate the safety at the same time. Results A total of 1029 patients were enrolled in this study without drop-out case. There was 1007 patients in full analysis set (FAS), whose average age was (32. 14±13. 69) years-old. The area under the ROC curve of FAS is 0. 909 (95% CI: 0. 891 to 0. 928). Based on the ROC curve of FAS, the optimal and the 95% specificity diagnostic cutoff values of MWD were 4. 25 mm and 5. 75 mm respec-tively. Based on different diagnostic cutoff value (3, 4. 25 and 5. 75 mm), the sensitivities of birch pol-len allergen SPT were 0. 9061 (95% CI 0. 8840-0. 9282), 0. 7973 (95% CI 0. 7669-0. 8277) and 0. 6706 ( 95% CI 0. 6351-0. 7062 ) respectively, whereas the specificity was gradually increased in sequence, which was 0. 6905 (95% CI 0. 6410-0. 7399), 0. 9018 (95% CI 0. 8700-0. 9336) and 0. 9524 (95% CI 0. 9296-0. 9752) respectively. There were 1029 patients in save set (SS), totally 7 adverse events observed among 6 patients (rate: 0. 58%, 6/1029). The manifestation was nasal itching, sneezing, runny nose, nasal obstruction, ocular itching, and large local cutaneous re-action of SPT. There was no severe adverse event. Conclusions SPT with birch pollen extract is an accu-racy and safe tool for the diagnosis of birch pollen allergy. The accuracy of diagnosis could be improved based on integration of medical history and different diagnostic threshold value of SPT.