High rate of sensitization to Kathon CG, detected by patch tests in patients with suspected allergic contact dermatitis.

BACKGROUND: Kathon CG, a combination of methylchloroisothiazolinone and methylisothiazolinone, is widely used as preservative in cosmetics, as well in household cleaning products, industrial products such as paints and glues. It has emerged as an important sensitizing agent in allergic contact dermatitis. OBJECTIVES: This study evaluated the reactivity to this substance in patients subjected to patch tests at the Dermatology Institute in Bauru, São Paulo from 2015 to 2017 and its correlation with other preservatives, the professional activity and location of the lesions. METHODS: The patients were submitted to standard series of epicutaneous tests, standardized by the Brazilian Group Studies on Contact Dermatitis. RESULTS: Out the 267 patients tested, 192 presented positivity to at least one substance and 29 of the patients (15.10%) presented reaction to Kathon CG, with predominance of the female gender (n=27); main professional activity associated with Kathon CG sensibilization was cleaning (17.24%), followed by aesthetic areas (13.79%) and health care (10.34%). The most prevalent sensitizations among the substances tested were nickel sulphate (56.3%), followed by cobalt chloride (23.4%), neomycin (18.2%), potassium dichromate (17.7%), thimerosal (14.5%), formaldehyde (13.2%), paraphenylenediamine (9.3%), and fragrance mix (8.3%). STUDY LIMITATIONS: We do not have data from patients that were submitted to patch test a decade ago in order to confront to current data and establish whether or no sensitization to Kathon CG has increased. CONCLUSION: High positivity to Kathon CG corroborates the recent findings in the literature, suggesting more attention to concentration of this substance, used in cosmetics and products for domestic use.

High rate of sensitization to Kathon CG, detected by patch tests in patients with suspected allergic contact dermatitis

Abstract Background: Kathon CG, a combination of methylchloroisothiazolinone and methylisothiazolinone, is widely used as preservative in cosmetics, as well in household cleaning products, industrial products such as paints and glues. It has emerged as an important sensitizing agent in allergic contact dermatitis. Objectives: This study evaluated the reactivity to this substance in patients subjected to patch tests at the Dermatology Institute in Bauru, São Paulo from 2015 to 2017 and its correlation with other preservatives, the professional activity and location of the lesions. Methods: The patients were submitted to standard series of epicutaneous tests, standardized by the Brazilian Group Studies on Contact Dermatitis. Results: Out the 267 patients tested, 192 presented positivity to at least one substance and 29 of the patients (15.10%) presented reaction to Kathon CG, with predominance of the female gender (n = 27); main professional activity associated with Kathon CG sensibilization was cleaning (17.24%), followed by aesthetic areas (13.79%) and health care (10.34%). The most prevalent sensitizations among the substances tested were nickel sulphate (56.3%), followed by cobalt chloride (23.4%), neomycin (18.2%), potassium dichromate (17.7%), thimerosal (14.5%), formaldehyde (13.2%), paraphenylenediamine (9.3%), and fragrance mix (8.3%). Study limitations: We do not have data from patients that were submitted to patch test a decade ago in order to confront to current data and establish whether or no sensitization to Kathon CG has increased. Conclusion: High positivity to Kathon CG corroborates the recent findings in the literature, suggesting more attention to concentration of this substance, used in cosmetics and products for domestic use.

Study of the frequency of allergens in cosmetics components in patients with suspected allergic contact dermatitis.

BACKGROUND: Contact dermatitis to cosmetics is a common dermatosis, especially in adults and professionals who handle them. OBJECTIVE: The objective of this study was to evaluate the frequency of sensitization to cosmetics' components in patients with suspected allergic contact dermatitis and to identify the main sensitizers related to occupational contact dermatitis. METHODS: During the period of January 2008 to June 2010, all the patients with a presumptive diagnosis of allergic contact dermatitis to cosmetics were selected. The patients were submitted to the patch tests of cosmetics series, composed by ten substances. RESULTS: Among the 147 patients studied sensitization to cosmetics components occurred in 31,29% of the cases, 14 of those (19,18%) equally corresponding to BHT and triethanolamine substances, 13 (17,81%) to ammonium thioglycolate, 09 to sorbic acid (12,33%), 08 to tosilamida (10,95%), 06 to germall (8,22%). The other elements tested showed indices of 5% or less. A higher frequency of contact dermatitis to cosmetics was observed in women and the age most affected was concordant with the age range of greatest professional activity of the population. CONCLUSION: Allergic contact dermatitis was more frequently associated with Triethanolamine, BHT and ammonium thioglycolate, and the relation with occupational contact dermatitis was discreet.

Study of the frequency of allergens in cosmetics components in patients with suspected allergic contact dermatitis / Estudo da frequência dos alérgenos da bateria de cosméticos em pacientes com suspeita de dermatite alérgica de contato

BACKGROUND: Contact dermatitis to cosmetics is a common dermatosis, especially in adults and professionals who handle them. OBJECTIVE: The objective of this study was to evaluate the frequency of sensitization to cosmetics' components in patients with suspected allergic contact dermatitis and to identify the main sensitizers related to occupational contact dermatitis. METHODS: During the period of January 2008 to June 2010, all the patients with a presumptive diagnosis of allergic contact dermatitis to cosmetics were selected. The patients were submitted to the patch tests of cosmetics series, composed by ten substances. RESULTS: Among the 147 patients studied sensitization to cosmetics components occurred in 31,29% of the cases, 14 of those (19,18%) equally corresponding to BHT and triethanolamine substances, 13 (17,81%) to ammonium thioglycolate, 09 to sorbic acid (12,33%), 08 to tosilamida (10,95%), 06 to germall (8,22%). The other elements tested showed indices of 5% or less. A higher frequency of contact dermatitis to cosmetics was observed in women and the age most affected was concordant with the age range of greatest professional activity of the population. CONCLUSION: Allergic contact dermatitis was more frequently associated with Triethanolamine, BHT and ammonium thioglycolate, and the relation with occupational contact dermatitis was discreet.

FUNDAMENTOS: A dermatite de contato por cosméticos é uma dermatose relativamente comum, sobretudo em adultos e em profissionais que os manipulam. OBJETIVO: O objetivo do estudo foi avaliar a freqüência de positividade aos componentes de cosméticos, em pacientes com suspeita de dermatite alérgica; e identificar os principais sensibilizantes relacionados à dermatite de contato ocupacional. MÉTODOS: Durante o período de janeiro de 2008 a junho de 2010 foram selecionados todos os pacientes com hipótese de dermatite alérgica de contato a cosméticos. Os pacientes foram submetidos aos testes epicutâneos com bateria de cosméticos, composta por dez substâncias. RESULTADOS: Dos 147 pacientes estudados, a sensibilização aos componentes do cosmético ocorreu em 31,29% dos casos, sendo 14 (19,18%) corresponderam igualmente às substâncias BHT e trietanolamina, 13 (17,81%) ao tioglicolato de amônia, 09 ao ácido sórbico (12,33%), 08 tonsilamida (10,95%), 06 germal (8,22%). Os demais elementos testados proporcionaram índices iguais ou inferiores a 5%. Observou-se maior freqüência de dermatite de contato aos componentes da bateria de cosméticos em mulheres e a idade mais acometida foi concordante com a faixa etária de maior atividade profissional da população. CONCLUSÕES: Houve maior freqüência de dermatite alérgica de contato pelas substâncias trietanolamina, BHT e tioglicolato de amônia, demonstrando pouca associação à dermatite de contato ocupacional.