Photoallergic contact cheilitis from methylchloroisothiazolinone/methylisothiazolinone: Where is the culprit product?

Keywords: case report; methylchloroisothiazolinone/methylisothiazolinone; photoallergic contact cheilitis; self-transported dermatitis EN case report methylchloroisothiazolinone/methylisothiazolinone photoallergic contact cheilitis self-transported dermatitis 199 200 2 02/25/21 20210301 NES 210301 CASE REPORT A 39-year-old woman was referred to our Contact Eczema Department with chronic cheilitis lasting 8 months. MCI/MI is a well-known potent allergen, having been nominated as "allergen of the year" in 2013.1 A new clinical entity has been suspected with MCI/MI,2 in terms of photoaggravated allergic contact dermatitis having been observed in some patients, mainly caused by MI.3 Photopatch testing is mandatory when diagnosing chronic cheilitis. [Extracted from the article]