Abstract Objective Evaluate biomarkers capable of safely guiding Yellow fever vaccine (YFV) vaccination among individuals suspicious of hen's egg allergy, and identify factors associated with a higher risk for adverse events after immunization (AEAI). Methods Patients underwent skin prick test (SPT) for standardized allergens: whole egg, egg white, egg yolk; YFV (1:10 dilution; Biomanguinhos-Fiocruz), and intradermal test (IDT; YFV 0.02 mL, 1:100 dilution) and positive and negative controls. Serum levels of specific IgE (sIgE) for a whole egg, egg white, egg yolk, egg albumin, ovomucoid, lysozyme, and conalbumin (ImmunoCap®; ThermoFisher®) were obtained. Patients sensitized to YFV were submitted to YFV desensitization, and those negatives received YFV (0.5mL) and remained under surveillance for at least one hour. Results 103 patients were enrolled, 95% under 12 years old. 71% (81/103) of patients had reactions: 80% immediate, 11% mixed, and 9% delayed. There was an association between positive skin test results with YFV and the severity of the reaction (OR:7.64; 95%CI:1.61-36.32; p =0,011). Only the presence of sIgE to ovomucoid was associated with clinical symptoms (p =0,025). Thirty patients underwent the YFV desensitization protocol. Conclusion There is a relationship between the positivity of the egg's components and the severity of the clinical reaction. Furthermore, the relationship between the positivity of the tests with the YFV and egg's components may show a tendency to look at ovomucoid and conalbumin, but it is not a certainty. Therefore, further studies are needed to confirm these associations, and for now, the authors still recommend using the vaccine for testing when necessary.

Abstract Objective Allergic sensitization is one of the key components for the development of allergies. Polysensitization seems to be related to the persistence and severity of allergic diseases. Furthermore, allergic sensitization has a predictive role in the development of allergies. The aim of this study was to characterize the pattern of sensitization of atopic patients treated at different pediatric allergy referral centers in Brazil. Methods A nation-wide transversal multicenter study collected data on patients attended in Brazil. Peripheral blood samples were collected to determine the serum levels of allergen-specific IgE. If allergen-specific IgE was higher than 0.1 kUA/L, the following specific components were quantified. Results A total of 470 individuals were enrolled in the study. Mite sensitization was the most frequent kind in all participants. A high frequency of sensitization to furry animals and grasses featured in the respiratory allergies. Regarding components, there was a predominance of sensitization to Der p 1 and Der p 2. It has been verified that having a food allergy, atopic dermatitis, or multimorbidity are risk factors for the development of more severe allergic disease. Conclusion Studies on the pattern of allergic sensitization to a specific population offer tools for the more effectual prevention, diagnosis, and treatment of allergic diseases. Sensitization to dust mites house was the most prevalent in the evaluated sample. High rates of sensitization to furry animals also stand out. Patients with food allergy, atopic dermatitis, or multimorbidity appear to be at greater risk for developing more severe allergic diseases.

Abstract Objectives: To describe the ontogeny of the immune system and the adaptive mechanisms of the immune system in the neonatal period, with an emphasis on transplacental antibody transport and breastfeeding. Source of data: Non-systematic literature review in the PubMed database. Summary of the findings: The last two decades have witnessed a great advance in the knowledge of the immune system since conception. Several investigation tools have provided insight on phenomena that were previously inadequately understood. Still expanding, the functional and molecular investigation of various aspects of the immune system will make it possible to understand how intra-uterus maternal-fetal exchanges, the maternal microbiota interacting with the fetus and newborn, and the acquisition of immunological competence occur in healthy and disease scenarios. Conclusions: In-depth knowledge of the development of the immune system and of the adaptive mechanisms that allow a safer transition to the extrauterine environment are fundamental components of optimizing maternal and young infant vaccination, as well as the strategies associated with full postnatal development, and the early diagnosis and treatment of innate errors of immunity.

Resumo Objetivo: Apesar dos programas de prevenção antitabagista, muitos adolescentes começam a fumar na idade escolar. Foram objetivos do estudo determinar a prevalência e os fatores de risco associados ao consumo de tabaco em adolescentes moradores do município de Uruguaiana, RS, Brasil. Métodos: Estudo transversal, feito com adolescentes de 12 a 19 anos, matriculados em escolas do município, que responderam questionário autoaplicável sobre tabagismo. Resultados: Participaram 798 adolescentes com igual distribuição entre os gêneros. A frequência de experimentação de tabaco (Alguma vez tentou fumar um cigarro, mesmo que uma ou duas tragadas) foi de 29,3%, 14,5% começaram a fumar antes dos 12 anos e 13% deles afirmaram ter fumado pelo menos um cigarro/dia no último mês. Foram identificados como associados ao tabagismo: ter amigo tabagista (OR: 5,67, IC95%: 2,06-7,09), ter oferta de cigarro pelo amigo (OR: 4,21, IC95%: 2,46-5,76) e facilidade de conseguir cigarros (OR: 3,82, IC95%: 1,22-5,41). Ter orientações dos pais sobre tabagismo (OR: 0,67, IC95%: 0,45-0,77), não ter contato com cigarro em casa na última semana (OR: 0,51, IC95%: 0,11-0,79) e saber os malefícios do cigarro eletrônico (OR: 0,88, IC95%: 0,21-0,92) foram identificados como de proteção. Conclusões: A prevalência de tabagismo entre os adolescentes de Uruguaiana é alta. A implantação de medidas nas escolas para reduzir ou acabar o consumo de tabaco e de suas novas modalidades, como os cigarros eletrônicos e o narguilé, é urgente e imperiosa.

Abstract Objective: Despite anti-smoking prevention programs, many adolescents start smoking at school age. The main objectives of this study were to determine the prevalence and risk factors associated with smoking in adolescents living in Uruguaiana, RS, Brazil. Methods: A prospective study was conducted in adolescents (12-19 years), enrolled in municipal schools, who answered a self-administered questionnaire on smoking. Results: 798 adolescents were enrolled in the study, with equal distribution between genders. The tobacco experimentation frequency (ever tried a cigarette, even one or two puffs) was 29.3%; 14.5% started smoking before 12 years of age and 13.0% reported smoking at least one cigarette/day last month. Having a smoking friend (OR: 5.67, 95% CI: 2.06-7.09), having cigarettes offered by friends (OR: 4.21, 95% CI: 2.46-5.76) and having easy access to cigarettes (OR: 3.82, 95% CI: 1.22-5.41) was identified as factors associated with smoking. Having parental guidance on smoking (OR: 0.67, 95% CI: 0.45-0.77), having no contact with cigarettes at home in the last week (OR: 0.51, 95% CI: 0.11-0.79) and knowing about the dangers of electronic cigarettes (OR: 0.88, 95% CI: 0.21-0.92) were identified as protection factors. Conclusion: The prevalence of smoking among adolescents in Uruguaiana is high. The implementation of measures to reduce/stop tobacco use and its new forms of consumption, such as electronic cigarettes and hookah, are urgent and imperative in schools.

Abstract Fabry disease, caused by deficient alpha-galactosidase A lysosomal enzyme activity, remains challenging to health-care professionals. Laboratory diagnosis in males is carried out by determination of alpha-galactosidase A activity; for females, enzymatic activity determination fails to detect the disease in about two-thirds of the patients, and only the identification of a pathogenic mutation in the GLA gene allows for a definite diagnosis. The hurdle to be overcome in this field is to determine whether a mutation that has never been described determines a ‘‘classic’’ or ‘‘nonclassic’’ phenotype, because this will have an impact on the decision-making for treatment initiation. Besides the enzymatic determination and GLA gene mutation determination, researchers are still searching for a good biomarker, and it seems that plasma lyso-Gb3 is a useful tool that correlates to the degree of substrate storage in organs. The ideal time for treatment initiation for children and nonclassic phenotype remains unclear.