Search

Background: Photopatch testing represents the gold standard for the diagnosis of photoallergic contact dermatitis (PACD). We aimed to identify common photoallergens in our tertiary dermatological referral centre from 2012 to 2021, to compare this to the preceding period studied, and data from other communities. Methods: We conducted a retrospective review of all 90 patients who underwent photopatch testing at the National Skin Centre, Singapore, between 2012 and 2021. Results: Of 90 patients, 19 (21.1%) were male, and the mean age was 41.6 years. Eighty‐four (93.3%) underwent testing to our standard sunscreen series, 10 (11.1%) to our extended series, and 73 (81.1%) to their own items. Seventeen (18.9%) were diagnosed with PACD (i.e., photocontact allergy with present or past relevance), 12 (13.3%) with ACD, and 4 (4.4%) with photoaugmented ACD. Relevant reactions were commonest to oxybenzone (8, 9.5%) and mexenone (3, 3.6%). Eleven (15.1%) had PACD to their own items, with 3 of 4 (75%) tested to ketoprofen diagnosed with PACD and the remaining 1 (25%) with photoaugmented ACD. Age, race, sex, atopy, and site of involvement were not associated with photocontact allergy. Compared to the preceding time period, the overall frequency of photocontact allergy and PACD decreased, but rates of photoallergic reactions to individual photoallergens were not significantly different. Conclusion: Organic ultraviolet absorbers such as oxybenzone and mexenone remained the most relevant photoallergens. Personal item testing was valuable, and testing to ketoprofen should be considered. [ABSTRACT FROM AUTHOR]

This retrospective study aims to identify the frequency, distribution, and temporal trends of contact allergens in the standard series at our tertiary referral centre over a 6-year period from 2014 to 2019. A multicentre study conducted in Central Europe found a slight increase in chromate allergy from 3.3% to 4.5% between 2015 and 2018.3 Once the relevance of these results is considered, our 1.4% is closer to the 1.1% observed in the American population.4 Nevertheless, we should monitor whether chromate sensitization continues to decline after peaking in 2015, which coincides with the European Union legislation on limiting hexavalent chromium content in leather. (iii) Exposed: the allergen had been encountered by the patient previously, but the patient did not develop dermatitis then. [Extracted from the article]