Rodrigo Pereira Duquia

Scalp seborrheic dermatitis: prevalence and associated factors in male adolescents

Background  The prevalence of seborrheic dermatitis (SD) in the general population is variable in the literature. Factors associated with SD are not well understood.

Sampling: how to select participants in my research study?

Background In this paper, the basic elements related to the selection of participants for a health research are discussed. Sample representativeness, sample frame, types of sampling, as well as the impact that non-respondents may have on results of a study are described. The whole discussion is supported by practical examples to facilitate the readers understanding. Objective To introduce readers to issues related to sampling.

Sample size: how many participants do I need in my research?

The importance of estimating sample sizes is rarely understood by researchers, when planning a study. This paper aims to highlight the centrality of sample size estimations in health research. Examples that help in understanding the basic concepts involved in their calculation are presented. The scenarios covered are based more on the epidemiological reasoning and less on mathematical formulae. Proper calculation of the number of participants in a study diminishes the likelihood of errors, which are often associated with adverse consequences in terms of economic, ethical and health aspects.

A case of Exophiala spinifera infection in Southern Brazil: Molecular identification and antifungal susceptibility

We report a case of an 80-year-old Brazilian man, farmer, with lesions on the dorsum of the hand. A direct mycological examination, cultivation and microculture slide observation was performed. The sequencing of ITS1-5.8S rDNA-ITS2 region was carried out and the etiological agent confirmed as Exophiala spinifera. The in vitro susceptibility of this isolate to antifungal agents alone and in combination was evaluated. This is the third case of phaeohyphomycosis caused by Exophiala spinifera in Brazil.

Prevalence of sun exposure and its associated factors in southern Brazil: a population-based study

BACKGROUND Sunlight exposure is responsible for a large number of dermatological diseases. OBJECTIVE We estimated the prevalence of sunlight exposure and its associated factors in adults from southern Brazil in a cross-sectional, population-based study. METHODS We investigated a representative sample of individuals aged ≥ 20 years (n=3,136). Sunlight exposure and its associated factors were evaluated in two distinct situations: at leisure time and at work. The time period investigated ranged from December 2004 to March 2005, comprising 120 days of the highest ultraviolet index in the urban area of the city of Pelotas, in southern Brazil. The participants were asked about sunlight exposure for at least 20 minutes between 10 A.M. and 4 P.M. The analysis was stratified by sex, and sunlight exposure was grouped into five categories. RESULTS Among the 3,136 participants, prevalence of sunlight exposure at the beach was 32.8% (95% CI, 30.3 - 35.2) and 26.3% (95% CI, 24.2 28.3) among men and women, respectively. The prevalence at work was 39.8% (95% CI, 37.2 - 42.4) among men and 10.5% (95% CI, 9.1 - 12.0) among women. Age was inversely associated with sunlight exposure. Family income and achieved schooling were positively associated with sunlight exposure at leisure time and inversely associated with sunglight exposure at work. Self-reported skin color was not associated. Knowledge of any friend or relative who has been affected by skin cancer was positively associated with sunlight exposure among men at work. CONCLUSION Despite the media campaigns on the harmful effects of excessive sunlight exposure, we found a high prevalence of sunlight exposure during a period of high ultraviolet index.

Prevalence and characteristics of Becker nevus in Brazilian 18-year-old males

ative after the start of anti-leprosy therapy owing to the presence of DNA fragments which remain in circulation for several weeks after bacilli death. Hence, further investigation within a larger group of patients is required to confirm the above statement and to prove the utility of PCR in urine for monitoring the response to anti-leprosy therapy. Although PCR 85A-C in urine was positive in two TT leprosy patients improving the laboratorial diagnosis that is difficult by conventional laboratorial technique, the strategy does not seem to be sufficiently sensitive for M. leprae detection in urine and needs to be further evaluated through the application of different set of primers and overcoming the PCR inhibition problems.

Field work I: selecting the instrument for data collection

The selection of instruments that will be used to collect data is a crucial step in the research process. Validity and reliability of the collected data and, above all, their potential comparability with data from previous investigations must be prioritized during this phase. We present a decision tree, which is intended to guide the selection of the instruments employed in research projects. Studies conducted along these lines have greater potential to broaden the knowledge on the studied subject and contribute to addressing truly socially relevant needs.

Presenting data in tables and charts

The present paper aims to provide basic guidelines to present epidemiological data using tables and graphs in Dermatology. Although simple, the preparation of tables and graphs should follow basic recommendations, which make it much easier to understand the data under analysis and to promote accurate communication in science. Additionally, this paper deals with other basic concepts in epidemiology, such as variable, observation, and data, which are useful both in the exchange of information between researchers and in the planning and conception of a research project.

Phacomatosis melanorosea with heterochromia of scalp hair

ejd.2011.1327 Auteur(s) : Hiram de Almeida Jr.1,3,4 hiramalmeidajr@hotmail.com, Rudolf Happle2, Flavia Reginatto1, Franciani Basso1, Rodrigo Duquia1,3 1 Dermatology, Santa Casa de Misericordia, Barroso 1202, 96010-280 Pelotas, Brazil 2 University of Marburg, Germany 3 Federal University de Pelotas, Brazil 4 Catholic University de Pelotas, Brazil Phacomatosis pigmentovascularis (PPV) represents a group of rare conditions characterized by the coexistence of an extensive telangiectatic nevus (nevus [...]

Dissatisfaction and acne vulgaris in male adolescents and associated factors.

BACKGROUND Acne vulgaris has high prevalence, disturbing quality of life during adolescence. OBJECTIVES To measure dissastifaction and acne in 18-year-old male individuals and its associated factors. METHODS A questionnaire was applied by trained interviewers to all boys during selection for the military service. Dissatisfaction and acne was evaluated using a self-administered face scale. Facial, prestrernal and dorsal acne were evaluated separately. RESULTS A total of 2,200 adolescents, aged 18 years, were interviewed. Among these, 1,678 had acne on the face and 974 (54.05%) showed some degree of dissatisfaction. Regarding the impact of acne located on the chest, 326 out of 686 adolescents (47.52%) reported dissatisfaction. For acne located on the back, 568 out of 1,103 affected individuals (51.50%) showed dissatisfaction. Facial / dorsal acne and dissatisfaction were statistically associated with lower income, lower education levels and with non-whites. Presternal acne and dissatisfaction were statistically asssociated with lower income and lower education levels. CONCLUSION This population-based study found a high prevalence of acne on the face, back and chest, with high rates of dissatisfaction.