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Abstract Introduction Azathioprine is a synthetic purine analogue derived from 6-mercaptopurine which acts by disrupting nucleic acid synthesis and interfering with T cell activation. It is effective in dermatology diseases related to the immune system. However, its side effects, including severe neutropenia, kept patients from using it. Mutations in thiopurine methyltransferase (TPMT) and inosine triphosphate pyrophosphohydrolase (ITPA) genes account for the major genetic polymorphism markers for azathioprine adverse risk factors in Caucasians, but not in Asians. The predictive value of the nucleoside diphosphate-linked moiety X motif 15 gene (NUDT15) has been studied in various diseases among different populations. The aim of our study was to determine the contribution of NUDT15 mutations in azathioprine-induced neutropenia in Han Chinese patients with dermatologic diseases. Methods The study enrolled all consecutive patients, older than 13 years old, with dermatological diseases currently treated orally with azathioprine in our clinic. Samples were also collected from patients with documented leukopenia in our prior study that examined the association between TPMT, ITPA, and neutropenia after informed reconsent. Complete blood count, differential count, and hepatic and renal function were checked regularly. The DNA samples for NUDT15 genotype were obtained from the patients. Results In total, we enrolled 56 patients (39 male, 17 female). The NUDT15 genotypes are mostly C/C (N = 36, 64.29%). Heterozygous variant (C/T) accounts for 30.36% (N = 17) and homozygous variant (T/T) accounts for 5.36% (N = 3). Among these patients, 15 patients (26.79%) developed neutropenia, including all three patients carry homozygous variant (T/T). The age-, sex-, and dose-adjusted risk of heterozygous variant compared to wild type is 9.383 (95% CI 1.32–66.96). Conclusions Pretreatment screening of NUDT15 might reduce the chance of azathioprine-induced neutropenia in Han Chinese patients with dermatologic diseases.

Acrylates are esters of acrylic acid, which are potent sensitizers that can cause occupational allergic contact dermatitis (ACD) in dental personnel. More recently, an increasing number of cases of both occupational and non-occupational ACD in beauty industry are observed. Here we present three cases of ACD to acrylate and its derivatives in both nail beauticians and do-it-yourself gel nail users due to exposure to nail cosmetics presenting with chronic hand eczema with severe pulpitis and even nail dystrophy with patch-test-confirmed diagnosis. Chemical analysis of commercial nail cosmetic products has been done in one of the patients and successfully identified 2-hydroxypropyl acrylate as the contact allergen. Keywords: Acrylic acid, Acrylate, Allergic contact dermatitis (ACD), Methacrylate, Nail cosmetic products

Background/Objective: Since 2005, there has been a significant increase in contact allergy to methylisothiazolinon (MI)/methylchloroisothiazolinone (MCI) incidences in European countries, but there has been no documented large-scale studies of such incidences in Taiwan. Methods: From 1987 to 2015, a total of 2590 patients received patch testing in our Contact Dermatitis Clinic. Analyzed were patients with positive reactions to MI/MCI (Kathon CG) in patch testing and with suspected allergy to MI/MCI. Results: Among the total 2590 patients, 2388 received patch testing during 1987–2005, while 202 received patch testing during 2006–2015. Because Kathon CG was not routinely patch tested for all patients from 1987 to 2005, the incidence of contact allergy to MI/MCI was thus corrected to 3/145 (2.1%) for this time period. After 2005, there were 11 patients (11/202, 5.4%) who showed positive reactions to MI/MCI. Amongst the 14 patients who showed positive reactions to MI/MCI, 12 of them were females (85.7%). The majority of the lesions was located on the hands (10 patients, 71.4%), along with the face (3 patients, 21.4%). Interestingly, 6 patients (42.9%) who showed positive reactions to MI/MCI were associated with contact allergy to essential oils, and five of them were aromatherapists. Conclusion: According to our study, the incidence of MI/MCI contact allergy in a referral center in Taiwan was 5.4%. A trend of increasing incidence of contact allergy to MI/MCI was noted after 2005, which is consistent with the findings in Europe. Allergic contact dermatitis to MI/MCI should be suspected in patients who have eczema on the hands and face, especially those who are aromatherapists.

Background/objective: Contact dermatitis to topical medicaments is commonly encountered in daily practice of dermatologists. The incidence and ranking of common allergens in topical medicaments may vary depending on local prescription and self-medication behavior. The objective of this study is to investigate the clinical features and common allergens of contact dermatitis to topical medicaments in Taiwan. Methods: From 1978 to 2005, a total of 3717 patients had been patch tested in our Contact Dermatitis Clinic. Any case with suspected contact allergy to topical medicaments receiving patch testing was included in this study. Results: During this period, a total of 608 patients were included and 603 of them completed the patch tests. Of the 603 patch-tested patients, 397 (66%) were positive for at least one antigen, and all patch tests were negative in 206 (34%). Patients with positive patch testing were characterized by younger age and location on the limbs and skin folds, while sex and atopy were not different among the two groups. A total of 1076 positive reactions to identifiable medicaments or main ingredients were recorded in 397 patients with positive patch testing. Among these positive reactions, 701/1076 counts (65%) were read as relevant. Traditional herbal medicaments (50%), antiseptics (21%), vehicle ingredients (9%), antibiotics (8%), corticosteroids (2%), anesthetics (2%), and nonsteroidal anti-inflammatory drugs (1%) were the most common sensitizers in this study, and the common concomitant allergens were fragrance (52%) and metal (20%). Conclusion: The results emphasized the special cultural consideration in Taiwanese patients with contact dermatitis to topical medicaments.

Background: Correlation of several patient factors with contact sensitization to nickel, cobalt, chromate, and other metal allergens has not been reviewed in the Taiwanese population. Objectives: A retrospective analysis was performed to define the characteristics of patients with positive patch tests to metals in a tertiary referral medical centre between 1978 and 2003. Patients and Methods: Patch test data of 3559 patients at a medical centre in Taiwan from 1978 to 2003 were retrospectively analysed. Contact sensitization to metals was defined as a positive reaction to at least one of the metal substances in the patch test series. Chi-squared test, Fisher’s exact test, and multivariate logistic regression were used for statistical analysis. Results: Female patients were more likely to have contact sensitization to metal allergens except chromate or mercurochrome. Patients who reacted to chromate were more likely to be male, with an occupational correlation, older age, and a site of predilection towards the extremities. Within the first and sixth decades of age, thimerosal and chromate were the leading causes of metal contact sensitization, respectively. Nickel was the major metal sensitizer among the other age groups. Conclusions: Several patient factors were characterized related to metal sensitization in the Taiwanese population. The sources of exposure were further discussed. [ABSTRACT FROM AUTHOR]