Andersen Hjalte H, Lundgaard Anna Charlotte, Petersen Anne S, Hauberg Lise E, Sharma Neha, Hansen Sofie D, Elberling Jesper, Arendt-Nielsen Lars
SMI®, Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark.
The Allergy Clinic, Copenhagen University Hospital, Gentofte, Copenhagen, Denmark.
PLoS One. 2016 May 23;11(5):e0156211. doi: 10.1371/journal.pone.0156211. eCollection 2016.
Skin prick test (SPT) is a common test for diagnosing immunoglobulin E-mediated allergies. In clinical routine, technicalities, human errors or patient-related biases, occasionally results in suboptimal diagnosis of sensitization.
Although not previously assessed qualitatively, lancet weight is hypothesized to be important when performing SPT to minimize the frequency of false positives, false negatives, and unwanted discomfort.
Accurate weight-controlled SPT was performed on the volar forearms and backs of 20 healthy subjects. Four predetermined lancet weights were applied (25 g, 85 g, 135 g and 265 g) using two positive control histamine solutions (1 mg/mL and 10 mg/mL) and one negative control (saline). A total of 400 SPTs were conducted. The outcome parameters were: wheal size, neurogenic inflammation (measured by superficial blood perfusion), frequency of bleeding, and the lancet provoked pain response.
The mean wheal diameter increased significantly as higher weights were applied to the SPT lancet, e.g. from 3.2 ± 0.28 mm at 25 g to 5.4 ± 1.7 mm at 265 g (p<0.01). Similarly, the frequency of bleeding, the provoked pain, and the neurogenic inflammatory response increased significantly. At 265 g saline evoked two wheal responses (/160 pricks) below 3 mm.
The applied weight of the lancet during the SPT-procedure is an important factor. Higher lancet weights precipitate significantly larger wheal reactions with potential diagnostic implications. This warrants additional research of the optimal lancet weight in relation to SPT-guidelines to improve the specificity and sensitivity of the procedure.
皮肤点刺试验（SPT）是诊断免疫球蛋白E介导的过敏反应的常用检测方法。在临床常规操作中，技术问题、人为失误或与患者相关的偏差偶尔会导致致敏诊断不理想。
尽管之前未进行定性评估，但推测采血针重量在进行皮肤点刺试验时很重要，可将假阳性、假阴性及不必要的不适频率降至最低。
对20名健康受试者的前臂掌侧和背部进行精确的重量控制皮肤点刺试验。使用两种阳性对照组胺溶液（1mg/mL和10mg/mL）和一种阴性对照（生理盐水），应用四种预先确定的采血针重量（25g、85g、135g和265g）。共进行了400次皮肤点刺试验。结果参数包括：风团大小、神经源性炎症（通过浅表血液灌注测量）、出血频率和采血针引起的疼痛反应。
随着采血针重量增加，皮肤点刺试验的平均风团直径显著增大，例如从25g时的3.2±0.28mm增至265g时的5.4±1.7mm（p<0.01）。同样，出血频率、引发的疼痛和神经源性炎症反应也显著增加。在265g时，生理盐水诱发了两次风团反应（/160次点刺），风团直径小于3mm。
皮肤点刺试验过程中采血针的应用重量是一个重要因素。更高的采血针重量会引发明显更大的风团反应，具有潜在的诊断意义。这需要针对皮肤点刺试验指南对最佳采血针重量进行更多研究，以提高该检测方法的特异性和敏感性。
