Association of frontal fibrosing alopecia and contact allergens in everyday skincare products in Hispanic females: a case-control study

Mariana de Figueiredo Silva Hafner: Design and planing of the study; drafting and editing of the manuscript; ollection, analysis, and interpretation of data; effective articipation in research orientation; intellectual particpation in the propaedeutic and/or therapeutic conduct f studied cases; critical review of the literature; critical eview of the manuscript; approval of the final version of he manuscript. Carolina Contin Proença: Effective participation in esearch orientation; intellectual participation in the ropaedeutic and/or therapeutic conduct of studied cases; ritical review of the literature; critical review of the anuscript; approval of the final version of the manuscript. Luciana Rodino Lemes: Effective participation in research rientation; intellectual participation in the propaedeutic nd/or therapeutic conduct of studied cases; critical review 4. Blaak J, Staib P. The relation of pH and skin cleansing. Curr Probl Dermatol. 2018;54:132--42. 5. Corazza M, Lauriola MM, Zappaterra M, Bianchi A, Virgili A. Surfactants, skin cleasing protagonists. J Eur Acad Dermatol Venereol. 2010;24:1--6. 6. Rodriguez KJ, Cunninghan C, Foxenberg R, Hoffman MSD, Vongsa R. The science behind wet wipes for infant skin: ingredient review, safety, and efficacy. Pediatric Dermatol. 2020;00:1--8. 7. Sasseville D, Alfalah M, Lacroix JP. ‘‘Parabenoia’’ Debunked, or ‘‘Who’s Afraid of Parabens?’’. Dermatitis. 2015;26:254--9. 8. anvisa.gov [Internet]. Resoluça ̃o da diretoria colegiada-RDC n 29, de 1 de junho de 2012 [cited 2020 Aug 29]. Available from: www.anvisa.gov.br/legis. 9. anvisa.gov [Internet]. Resoluça ̃o da diretoria colegiadaRDC no 3, de 21 de janeiro de 2012 [cited 2020 Jul 25]. Available from: www.anvisa.gov.br/legis. 10. Pogačar MS, Maver U, Varda NM, Mičetić-Turk D. Diagnosis and

screen use. 1 We sought to identify a possible association between FFA and sunscreen use in our patient population. A case-control study with thirty-six Hispanic females; eighteen cases and eighteen sex-and age-matched controls, was designed. The protocol was approved by the local ethics committee of the University Hospital ''Dr. José Eleuterio González'' in Monterrey, Mexico. A questionnaire inquiring about hygiene products and sunscreens, including time of use, was formulated. Patients and controls were patch tested using allergens from allergEAZE's Standard, Cosmetic, and Photopatch series. Readings were performed 48 and 96 hours after application. Reactions were measured by the North American Contact Dermatitis Group criteria. 2 FFA patients seen in our Dermatology clinic from 2012---2018 were included. Fisher's exact test was used to compare between groups. Statistical significance was considered p < 0.05.
The mean age of FFA patients was 59.1 and 56.5 years for controls. Sixteen cases were postmenopausal. Ten subjects Hair loss outside of the scalp was noted in fifteen cases. All had eyebrow, twelve limb, and ten eyelash involvements. Eight individuals presented facial papules. Table 1 outlines the use of hygiene products. Sunscreen use in FFA subjects was almost double in comparison with healthy controls (p = 0.035). Makeup foundation was used by fourteen patients in each group. FFA cases used more facial moisturizers compared to controls, without statistical significance.
Fifteen patients had positive reactions to at least one allergen against ten controls, no significant difference was found. The most common allergens in FFA were iodopropynyl butylcarbamate and propolis ( Table 2). We reviewed patients' hygiene products and made avoidance recommendations.
Aldoori et al. suggested environmental factors associated to FFA; with a significant difference in sunscreen use compared to controls. Forty patients were patch tested; more positive reactions to linalool hydroperoxide and Balsam of Peru were found in subjects with FFA versus general patch tested subjects. 3 Rocha et al. did not observe differences in sixty-three FFA patients in comparison with local patch tested individuals, nor photoallergy was detected. 4 Identified allergens in FFA are unable to explain the association between disease and sunscreen use. 5 Thompson et al. found Titanium Dioxide (TiO 2 ) nanoparticles in hair shafts of FFA patients and asymptomatic controls; no positive reactions in eight FFA patients patch tested to five titanium types were found. It is unclear if TiO 2 plays a role in FFA pathogenesis. 6 Recently Rudnicka et al. patch tested 20 patients with FFA and 24 healthy controls finding a positive patch test reaction to one or more allergen in 65% of the cases, while only 37.5% of the controls had a positive reaction. The most common allergens encountered in the FFA group were cobalt chloride hexahydrate 35%, nickel sulfate hexahydrate 25%, and potassium dichromate 15%. 7 In our study, 83.3% of cases and 55.5% of controls had at least one positive allergen.
Our study included sex-and age-matched healthy controls, while most of the previous publications have a general patch test population. Limitations include small sample size, recall bias for sunscreen use, lack of genetic studies, and generalizability due to racial/ethnic homogeneity.
In conclusion, FFA's etiopathogenesis remains unknown. Increased sunscreen use and a greater prevalence of contact allergy was demonstrated in our FFA patients. Raising the question of whether allergic/immunologic responses in genetically predisposed patients could be triggered by exogenous substances. Our statistically non-significant greater prevalence of contact allergy and heterogeneity of results in previous studies endorses the need for further research to confirm this association.

Financial support
None declared.

Authors' contributions
Sonia Sofia Ocampo-Garza: Conception and design of the study; acquisition of data; analysis and interpretation; drafting the article; final approval of the version submitted.
Maira Elizabeth Herz-Ruelas: Conception and design of the study; analysis and interpretation; revising the article; final approval of the version submitted.
Sonia Chavez-Alvarez: Conception and design of the study; revising the article; final approval of the version submitted.
David Marcelo de la Fuente-Rodriguez: Acquisition of data; final approval of the version submitted.
Jorge Ocampo-Candiani: Conception and design of the study; analysis and interpretation; revising the article; final approval of the version submitted.

Conflicts of interest
None declared.

Dear Editor,
The elucidation of pathophysiological mechanisms and the development of new treatments for psoriasis require periodic updates in the publication of consensuses, algorithms and treatment guides.
In Brazil, the ethnic composition, increased longevity, in addition to climatic and insolation characteristics may imply unique epidemiological data and different regional prevalence rates of psoriasis, in addition to influence dis- ease severity and therapeutic response. Recent data from the Brazilian Society of Dermatology estimate the prevalence of psoriasis in Brazil at 1.31%, with 1.15% (95% CI 0.90% to 1.43%) in women and 1.47% (95% CI 1.11% to 1.82%) in men (p = 0.22). An increase in the prevalence of psoriasis (p < 0.01) was identified in relation to age groups, which was 0.58% (95% CI 0.31% to 0.84%) under the age of 30; 1.39% (95% CI 1.10% to 1.74%) between 30 and 60 years old; and 2.29% (95% CI 1.71% to 2.84%) in individuals over 60 years. The geographical regions of the country differed in terms of disease prevalence (p = 0.02), with higher indicators in the South and Southeast regions, in contrast to the Midwest, North and Northeast regions. 1 In parallel, 73.4% of Brazilian patients with moderate to severe psoriasis report impaired health-related quality of life. 2 The Brazilian Consensus on Psoriasis 2020 and the Treatment Algorithm of the Brazilian Society of Dermatology (SBD), created with the collaboration of experts from all regions of Brazil is shown below (Fig. 1).
In preparing this consensus, the stratification of the levels of evidence and their grade of recommendation was used,