Department of Dermatology, University Hospital Zurich, Zurich, Switzerland; Faculty of Medicine, University of Zurich, Zurich, Switzerland.
Department of Dermatology, University Hospital Zurich, Zurich, Switzerland; Faculty of Medicine, University of Zurich, Zurich, Switzerland; Competence Center Personalized Medicine, University of Zurich and ETH Zurich, Zurich, Switzerland.
Allergol Int. 2019 Apr;68(2):254-258. doi: 10.1016/j.alit.2018.12.001. Epub 2018 Dec 29.
Patch testing of contact allergens to diagnose allergic contact dermatitis (ACD) is a traditional, useful tool. The most important decision is the distinction between allergic and irritant reactions, as this has direct implications on diagnosis and management. Our objective was to evaluate a new method of non-contact infrared reading of patch tests. Secondary objectives included a possible correlation between the intensity of the patch test reaction and temperature change.
420 positive reactions from patients were included in our study. An independent patch test reader assessed the positive reactions and classified them as allergic (of intensity + to +++) or irritant (IR). At the same time, a forward-looking infrared (FLIR) camera attachment for an iPhone was used to acquire infrared thermal images of the patch tests, and images were analyzed using the FLIR ONE app.
Allergic patch test reactions were characterized by temperature increases of 0.72 ± 0.67 °C compared to surrounding skin. Irritant reactions only resulted in 0.17 ± 0.31 °C temperature increase. The mean temperature difference between the two groups was highly significant (p < 0.0001) and therefore was used to predict the type of contact dermatitis.
Thermography is a reliable and effective way to distinguish between allergic and irritant contact dermatitis.
接触过敏原斑贴试验诊断变应性接触性皮炎（ACD）是一种传统的、有用的工具。最重要的决策是区分变应性和刺激性反应，因为这对诊断和管理有直接影响。我们的目的是评估一种新的非接触式红外读取斑贴试验的方法。次要目标包括斑贴试验反应强度与温度变化之间的可能相关性。
我们的研究纳入了 420 例阳性反应患者。一名独立的斑贴试验读者评估了阳性反应，并将其分类为变应性（强度为+至+++）或刺激性（IR）。同时，使用 iPhone 的前视红外（FLIR）相机附件获取斑贴试验的红外热图像，并使用 FLIR ONE 应用程序分析图像。
与周围皮肤相比，变应性斑贴试验反应的特征是温度升高 0.72±0.67°C。刺激性反应仅导致 0.17±0.31°C 的温度升高。两组之间的平均温差具有高度显著性（p<0.0001），因此可用于预测接触性皮炎的类型。
热成像法是区分变应性和刺激性接触性皮炎的可靠有效的方法。
