Standard photopatch test battery? Proposal based on current epidemiology and experience in our Skin Allergy Unit

BACKGROUND The diagnosis of photoallergic contact dermatitis (PACD) is confirmed by photopatch testing (PPT). In Spain, the latest recommendation on which allergens to test in PPT dates from 1995. METHODS In the last 4 years, we studied 455 patients with epicutaneous tests and performed PPT on 33 of those patients (7.3%). RESULTS The most prevalent allergens in PPT were as follows: non-steroidal anti-inflammatory drugs (NSAIDs) (46%), fragrances (21%), and solar filters (18%). DISCUSSION In our country, the most common photoallergens continue to be NSAIDs (ketoprofen). The increasingly common use of sunscreens has led to a growing involvement of solar filters in PACD, which can be also contained in other cosmetics. In our experience, PACD due to fragrances is nonetheless at least similar in frequency. CONCLUSIONS The PPT battery must adapt to the prescription, use, and exposure habits of each country. We propose a diagnostic model to guide which allergens to test in PPT, which in our experience should also include fragrances.