Gloistein Claas, Astvatsatourov Anatoli, Allekotte Silke, Mösges Ralph
Institute of Medical Statistics, Informatics and Epidemiology, Faculty of Medicine, University of Cologne, Cologne, Germany.
Int Arch Allergy Immunol. 2015;168(4):277-84. doi: 10.1159/000443273. Epub 2016 Feb 20.
Allergic reactions in patients with seasonal or perennial rhinoconjunctivitis mediated by airborne allergens can be effectively assessed with the conjunctival provocation test (CPT). The CPT is a fast and easy diagnostic procedure that challenges the ocular mucosa with instillations of allergen solutions into the conjunctival region. This paper aimed to investigate the possible influence of repeated diagnostic CPT procedures on the patient's clinical presentation, i.e. to analyze desensitization effects caused by diagnostic solutions and to show the reproducibility of CPT results.
Treatment progress in 120 placebo-treated patients from 2 immunotherapeutic dose-finding studies was estimated and documented, as based on the CPT which was applied at 4 visits with intervals of 4, 8 and 16 weeks. High-resolution digital photos collected as part of the CPT documentation were analyzed by an external observer and by digital analysis software to determine conjunctival redness, completely independent of the subjectivity of investigators and patients.
Two extremal scenarios of the redness changes were considered after provocation with 10,000 standard quality units/ml. A maximal decrease of about 3% (t test: p = 0.0002; U test: p = 0.001) and a minimal decrease of about 1% (t test: p = 0.254; U test: p = 0.431) were found.
The observed decrease in conjunctival hyperemia can be explained by local desensitization or by placebo effect. Due to the setup of both studies considered, we could not ascertain how these factors influence the decrease in redness. In order to attribute the observed effects to local conjunctival desensitization with certainty, further pilot studies are needed.
通过结膜激发试验（CPT）可以有效评估由空气传播变应原介导的季节性或常年性鼻结膜炎患者的过敏反应。CPT是一种快速简便的诊断程序，通过向结膜区域滴注变应原溶液来刺激眼黏膜。本文旨在研究重复进行诊断性CPT程序对患者临床表现的可能影响，即分析诊断溶液引起的脱敏作用，并展示CPT结果的可重复性。
对来自2项免疫治疗剂量探索研究的120例接受安慰剂治疗的患者的治疗进展进行评估并记录，评估基于在4次就诊时进行的CPT，就诊间隔为4周、8周和16周。作为CPT记录一部分收集的高分辨率数码照片由外部观察者和数字分析软件进行分析，以确定结膜充血情况，完全独立于研究者和患者的主观性。
在用10000标准质量单位/毫升激发后，考虑了充血变化的两种极端情况。发现最大下降约3%（t检验：p = 0.0002；U检验：p = 0.001），最小下降约1%（t检验：p = 0.254；U检验：p = 0.431）。
观察到的结膜充血减少可由局部脱敏或安慰剂效应来解释。由于所考虑的两项研究的设置，我们无法确定这些因素如何影响充血的减少。为了确定地将观察到的效应归因于局部结膜脱敏，需要进一步的试点研究。
