Update on the pathogenesis of vitiligo

Abstract Vitiligo is a complex disease whose pathogenesis results from the interaction of genetic components, metabolic factors linked to cellular oxidative stress, melanocyte adhesion to the epithelium, and immunity (innate and adaptive), which culminate in aggression against melanocytes. In vitiligo, melanocytes are more sensitive to oxidative damage, leading to the increased expression of proinflammatory proteins such as HSP70. The lower expression of epithelial adhesion molecules, such as DDR1 and E-cadherin, facilitates damage to melanocytes and exposure of antigens that favor autoimmunity. Activation of the type 1-IFN pathway perpetuates the direct action of CD8+ cells against melanocytes, facilitated by regulatory T-cell dysfunction. The identification of several genes involved in these processes sets the stage for disease development and maintenance. However, the relationship of vitiligo with environmental factors, psychological stress, comorbidities, and the elements that define individual susceptibility to the disease are a challenge to the integration of theories related to its pathogenesis.

Tratamento do vitiligo em progressão com minipulso oral de dexametasona / Treatment of developing vitiligo with oral mini-pulse of dexamethasone

Introdução: Foram analisados retrospectivamente dados de 26 pacientes com vitiligo em progressão, submetidos a protocolo de tratamento com minipulso oral de dexametasona. A resposta clínica e os efeitos colaterais foram avaliados em intervalos mensais. Dos 26 pacientes incluídos no protocolo de estudo, 12 (46,2%) apresentaram repigmentação das lesões, 11 (42,3%) estabilização, e três (11,5%) progressão da doença. Dez pacientes (38,5%) apresentaram efeitos colaterais, sendo o aumento de peso a reação adversa mais comum. Houve associação entre tempo de tratamento e frequência dos efeitos colaterais.

Introduction: The authors have carried out a retrospective analysis of data from 26 patients with developing vitiligo who were treated with oral mini-pulse of dexamethasone. Clinical response and side effects were evaluated at monthly intervals. Of the 26 patients included in the study, 12 (46.2%) presented a repigmentation of lesions, 11 (42.3%) stabilized, and 3 (11.5%) experienced a worsening of the condition. Ten patients (38.5%) had side effects, the most common of which was weight gain. There was a correlation between the duration of the treatment and the frequency of side effects.

Armadillo meat intake was not associated with leprosy in a case control study, Curitiba (Brazil)

Leprosy's progression and its maintained endemic status, despite the availability of effective treatments, are not fully understood and recent studies have highlighted the possibility of involved Mycobacterium leprae ambient reservoirs. Wild armadillos can carry leprosy and, because their meat is eaten by humans, development of the disease among armadillo meat consumers has been investigated. This study evaluated the frequency of armadillo meat intake among leprosy patients as well as age and gender matched controls with other skin diseases from a dermatological unit. Armadillo meat consumption among both groups was adjusted by demographic and socioeconomic covariates based on a conditional multiple logistic regression model. One hundred twenty-one cases and 242 controls were evaluated; they differed in socioeconomic variables such as family income, hometown population and access to treated water. The multivariate analysis did not show an association between the intake of armadillo meat and leprosy (odds ratio = 1.07; CI 95 percent 0.56-2.04), even when only cases with no known contacts were analyzed. We conclude that leprosy is not associated with the intake of armadillo meat in these patients.

Avaliação do padrão de uso de protetor solar em pacientes com vitiligo / Evaluation of sunscreen use patterns in vitiligo patients

Fundamentos: Acredita-se que pacientes com vitiligo pertençam a um grupo mais susceptível para o desenvolvimento de neoplasias malignas da pele devido à ausência de melanina na pele afetada. Por isso, o uso de protetor solar é fundamental nesses pacientes. Objetivo: Avaliar o padrão de uso de protetor solar em pacientes com vitiligo. Métodos: Foi desenvolvido estudo transversal através de questionário e exame físico em pacientes com vitiligo, de agosto de 2009 a abril 2010, tendo sido analisadas as variáveis: dados demográficos; características clínicas do vitiligo; uso de protetor solar e hábitos de exposição solar. Resultados: Participaram do estudo 121 pacientes, dos quais 43 usavam diariamenteprotetor solar, em sua maioria com FPS 30. As variáveis associadas ao uso diário foram sexo feminino (P = 0.001,OR = 4,76; 95% IC = 1,80-12,59) e recomendação pelo dermatologista na primeira consulta (P = 0.047, OR = 2,28; 95% IC = 1,01-5,28). Conclusão: Foi determinado um padrão de uso de protetor solar em pacientes com vitiligo.Além disso, foi identificado que o aconselhamento do dermatologista teve significância estatística no uso de protetor solar por esses indivíduos (P = 0.047, OR = 2,28; 95% IC = 1,01-5,28).

Introduction: Since patients with vitiligo are believed to be more susceptible to developing malignant neoplasias due to the lack of melanin in the affected skin, the use of sunscreens is critically important. Objective:To evaluate the pattern of sunscreen usage in vitiligo patients. Methods: A transverse study of vitiligo patients was conducted from August 2009 to April 2010. The following variables were studied using a questionnaire and physical examination: demographic data (gender, age, education level, and phototype); clinical characteristics of the condition (age at diagnosis, affected areas of the body, and clinical type); sunscreen use (frequency, protection factor, and duration of use); and habits of sun exposure. Results: Of the 121 study subjects, 43 used sunscreen – mainly with sun protection factor 30 – on a daily basis.The variables associated with daily use were female gender (p = 0.001, OR = 4.76, 95% CI = 1.80-12.59) and recommendation by a dermatologist in the first medical visit (p = 0.047, OR=2.28, 95% CI = 1.01-5.28). Conclusion: A pattern of sunscreen usage was determined for patients with vitiligo. In addition, it was verified that a dermatologist's recommendation to wear sunscreen had a statistically significant impact (p = 0.047, OR=2.28, 95% CI = 1.01-5.28).