Codeço Carlos, Alves Pedro Botelho, Figueiredo Ana Carolina, Flor Duarte, Gonçalo Margarida
Occupational Medicine, Instituto Português de Oncologia, Coimbra, Portugal.
Allergy and Clinical Immunology Unit, Centro Hospitalar Universitário de Coimbra, Coimbra, Portugal.
Contact Dermatitis. 2023 Jun;88(6):438-445. doi: 10.1111/cod.14297. Epub 2023 Mar 1.
Photopatch testing has been standardized for diagnosing photoallergic contact dermatitis but is still infrequently used.
To characterize photopatch test (PPT) results and their clinical relevance.
We collected retrospective data from patients photopatch tested in our Dermatology Unit (2010-2021), using the European PPT 'baseline' series, other allergens, and patient's own products, when appropriate.
Out of 223 patients, 75 patients (33.6%) were reactive with 124 positive PPT reactions, considered relevant in 56/223 patients (25.1%) and in 72/124 reactions (58.1%). Most reactions were caused by topical drugs (n = 33; 45.8%), such as ketoprofen or promethazine, and 7 (9.8%) by systemic drugs, such as hydrochlorothiazide and fenofibrate. 'Classical' ultraviolet filters were responsible for six positive PPT reactions whereas there was only three relevant PPT to the 'newer' UV filters. Patients' sunscreens/cosmetics or plant extracts caused 10 positive PPT each. Additional patch test reactions were observed, mostly to Tinosorb® M.
Contrary to the trend in ACD, most positive PPT reactions were caused by topical drugs, outweighing ultraviolet filters and cosmetics. We stress the low reactivity to the 'newer' UV filters included in the PPT series. PPT was occasionally positive in systemic drug photosensitivity, but overall PPT reactivity was low.
光斑贴试验已标准化用于诊断光变应性接触性皮炎，但仍较少使用。
描述光斑贴试验（PPT）结果及其临床相关性。
我们收集了在皮肤科接受光斑贴试验的患者（2010 - 2021年）的回顾性数据，使用欧洲PPT“基线”系列、其他变应原以及在适当情况下患者自己的产品。
在223例患者中，75例（33.6%）有反应，共出现124次阳性PPT反应，其中56/223例患者（25.1%）及72/124次反应（58.1%）被认为具有相关性。大多数反应由局部用药引起（n = 33；45.8%），如酮洛芬或异丙嗪，7次（9.8%）由全身用药引起，如氢氯噻嗪和非诺贝特。“经典”紫外线滤过剂导致6次阳性PPT反应，而对“新型”紫外线滤过剂仅有3次相关的PPT反应。患者的防晒霜/化妆品或植物提取物各引起10次阳性PPT反应。还观察到其他斑贴试验反应，大多针对Tinosorb® M。
与变应性接触性皮炎的趋势相反，大多数阳性PPT反应由局部用药引起，超过了紫外线滤过剂和化妆品。我们强调对PPT系列中“新型”紫外线滤过剂的低反应性。在全身药物光敏反应中，PPT偶尔呈阳性，但总体PPT反应性较低。
