Photopatch testing in Chinese patients: A 5-year experience

Photopatch testing in Singapore: A 10-year retrospective study

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.

Analysis of Adverse Reactions of Cosmetics in Chinese Han Population in Recent Five Years

Background

There are still some gaps in the summary and generalization of cosmetic-related adverse reaction reports.

Objective

The aim of this study is to summarize and analyze the occurrence of cosmetic adverse reactions in Shanghai Han population by using available survey data.

Materials and Methods

Collection, statistics and analysis of patients with cosmetic adverse reactions in Shanghai Huashan Hospital from 2017 to 2021.

Results

Among the 1004 patients, most of them (96.71%) were diagnosed as cosmetic contact dermatitis, which often occurred within 3 days of using cosmetics (51.79%). A total of 260 patients were tested with patch test, but the compliance rate was only 18.08%. Among them, 240 patients underwent additional European standard allergen tests, and positive allergens were detected in 210 cases (87.5%). Univariate analysis revealed that dosage form (emulsion and cream), age (≤25 years) and the allergic ingredients triethanolamine, rose oil, propylene glycol, thiomersal and musk ambrette are associated with the occurrence of cosmetic adverse reactions within seven days. A logit prediction model was also successfully constructed: Logit (P) = 1.710-0.796×1 + 1.185×2 -3.650X3-1.335X4.

Conclusion

This study complements the data reported on cosmetic adverse reactions in the Chinese Han population and suggests that in future clinical diagnosis and data collection, emphasis should be placed on patch testing, combining the patch test with cosmetic protoplast with the European standard allergen test to improve the detection rate.

Patch Testing With Benzophenone-3 and -4: The North American Contact Dermatitis Group Experience, 2013-2020

Background: Benzophenone (BZP)-3 and BZP-4 are ultraviolet (UV) absorbers used in sunscreens and personal care products (PCPs) and may cause allergic contact dermatitis. Objective: To characterize positive patch test reactions to BZP-3 (10% in petrolatum [pet]) and BZP-4 (2% pet) in a screening allergen series. Methods: Retrospective analysis of patients tested to BZP-3 and BZP-4 was conducted by the North American Contact Dermatitis Group from 2013 to 2020. Results: Of 19,618 patients patch tested to BZP-3 and BZP-4, 103 (0.5%) and 323 (1.6%) had positive reactions, respectively: 413 (2.1%) reacted to at least 1 BZP (BZP-positive patient). As compared with BZP-negative patients, BZP-positive patients were significantly more likely to have a history of hay fever (39.3% vs 33.4%, P = 0.0134), history of atopic dermatitis (39.8% vs 30.7%, P = 0.0001), and facial involvement (37.4% vs 32.2%, P = 0.0272). Most reactions were currently clinically relevant (BZP-3: 90.4%; BZP-4: 65.8%). Common identified sources included PCPs and sunscreens. Coreactivity between BZP-3 and BZP-4 was low: 13.5% (14/104) of BZP-3-positive patients were allergic to BZP-4 and 4.3% (14/322) of BZP-4-positive patients were allergic to BZP-3. Conclusions: Eight-year prevalence of BZP positivity was 2.1%. Reactions were frequently clinically relevant and linked to PCPs and sunscreens.

Photosensitivity is an important cause of refractory facial erythema in atopic dermatitis: A retrospective study of 82 Chinese patients

BACKGROUND

Ultraviolet radiation can aggravate facial erythema in atopic dermatitis (AD) patients.

OBJECTIVE

To investigate the photobiological testing results of Chinese AD patients with refractory facial erythema.

METHODS

We conducted a retrospective analysis of 82 AD patients with refractory facial erythema who visited our department during 2004-2021. All of them completed phototesting and photopatch testing.

RESULTS

82 patients were enrolled in the study, and 53 (64.6%) were between 18 and 30 years old. 51.2% (42/82) had positive phototesting results and were considered photosensitive AD (PhAD) patients. One-third of them were both allergic to ultraviolet A and ultraviolet B. 65.9% (54/82) suffered from photoallergic contact dermatitis. Chlorpromazine (50.7%), potassium dichromate (13.2%), and thimerosal (11.8%) were the top three common photoallergens. Overall, 86.3% of AD patients with refractory facial erythema had direct photoallergy or photocontact allergy. PhAD patients had fewer allergic comorbidities than the other group (p = .007). More non-PhAD patients (55.0%) suffered from AD at 2-14 years old (p = .015).

CONCLUSIONS

Photosensitivity contributes a lot to the facial lesions of AD patients, especially in their 20s. 86.3% of these patients had direct photoallergy or photocontact allergy. Therefore, AD patients with facial erythema should undergo phototesting and photopatch testing routinely.