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BackgroundAllergen exposure leads to allergen sensitization in susceptible individuals and this might influence allergic rhinitis (AR) phenotype expression. We investigated whether sensitization patterns vary in a country with subtropical and tropical regions and if sensitization patterns relate to AR phenotypes or age.MethodsIn a national, cross-sectional study AR patients (2-70 y) seen by allergists underwent blinded skin prick testing with a panel of 18 allergens and completed a validated questionnaire on AR phenotypes.Results628 patients were recruited. The major sensitizing allergen was house dust mite (HDM) (56%), followed by Bermuda grass (26%), ash (24%), oak (23%) and mesquite (21%) pollen, cat (22%) and cockroach (21%). Patients living in the tropical region were almost exclusively sensitized to HDM (87%). In the central agricultural zones sensitization is primarily to grass and tree pollen. Nationwide, most study subjects had perennial (82.2%), intermittent (56.5%) and moderate-severe (84.7%) AR. Sensitization was not related to the intermittent-persistent AR classification or to AR severity; seasonal AR was associated with tree (p < 0.05) and grass pollen sensitization (p < 0.01). HDM sensitization was more frequent in children (0-11 y) and adolescents (12-17 y) (subtropical region: p < 0.0005; tropical region p < 0.05), but pollen sensitization becomes more important in the adult patients visiting allergists (Adults vs children + adolescents for tree pollen: p < 0.0001, weeds: p < 0.0005).ConclusionsIn a country with (sub)tropical climate zones SPT sensitization patterns varied according to climatological zones; they were different from those found in Europe, HDM sensitization far outweighing pollen allergies and Bermuda grass and Ash pollen being the main grass and tree allergens, respectively. Pollen sensitization was related to SAR, but no relation between sensitization and intermittent-persistent AR or AR severity could be detected. Sensitization patterns vary with age (child HDM, adult pollen). Clinical implications of our findings are dual: only a few allergens –some region specific- cover the majority of sensitizations in (sub)tropical climate zones. This is of major importance for allergen manufacturers and immunotherapy planning. Secondly, patient selection in clinical trials should be based on the intermittent-persistent and severity classifications, rather than on the seasonal-perennial AR subtypes, especially when conducted in (sub)tropical countries.

Introduction In the light of the current COVID-19 pandemic, during which the world is confronted with a new, highly contagious virus that suppresses innate immunity as one of its initial virulence mechanisms, thus escaping from the first-line human defense mechanisms, enhancing innate immunity seems a good preventive strategy. Methods Without the intention to write an official systematic review, but more to give an overview of possible strategies, in this review article we discuss several interventions that might stimulate innate immunity and thus our defense against (viral) respiratory tract infections. Some of these interventions can also stimulate the adaptive T- and B-cell responses, but our main focus is on the innate part of immunity. We divide the reviewed interventions in: 1) lifestyle related (exercise, >7 hours sleep, forest walking, meditation/mindfulness, vitamin supplementation); 2) Non-specific immune stimulants (letting fever advance, bacterial vaccines, probiotics, dialyzable leukocyte extract, pidotimod) and 3) specific vaccines with heterologous effect (BCG vaccine, mumps-measles-rubeola vaccine, i.e.). Results For each of these interventions we briefly comment on their definition, possible mechanisms and evidence of clinical efficacy or lack of it, especially focusing on respiratory tract infections, viral infections and eventually a reduced mortality in severe respiratory infections in the intensive care unit. At the end a summary table demonstrates the best trials supporting (or not) clinical evidence. Conclusion Several interventions have some degree of evidence for enhancing the innate immune response and thus conveying possible benefit, but specific trials in COVID-19 should be conducted to support solid recommendations.

Este artículo debe citarse como: Larenas-Linnemann D, Salas-Hernández J, Vázquez-García JC, Ortiz-Aldana I, Fernández-Vega M, Del Río-Navarro BE, et al. Guía Mexicana del Asma 2017. Rev Alerg Mex. 2017;64 Supl 1:s11-s128. AbstractBackground: The need for a national guideline, with a broad basis among specialists and primary care physicians was felt in Mexico, to try unifying asthma management. As several high-quality asthma guidelines exist worldwide, it was decided to select the best three for transculturation. Methods: Following the internationally recommended methodology for guideline transculturation, ADAPTE, a literature search for asthma guidelines, published 1-1-2007 through 31-12-2015 was conducted. AGREE-II evaluations yielded 3/40 most suitable for transculturation. Their compound evidence was fused with local reality, patient preference, cost and safety considerations to draft the guideline document. Subsequently, this was adjusted by physicians from 12 national medical societies in several rounds of a Delphi process and 3 face-to-face meetings to reach the final version. Results: Evidence was fused from British Thoracic Society Asthma Guideline 2014, Global Initiative on Asthma 2015, and Guía Española del Manejo del Asma 2015 (2016 updates included). After 3 Delphi-rounds we developed an evidence-based document taking into account patient characteristics, including age, treatment costs and safety and best locally available medication. Conclusion: In cooperation pulmonologists, allergists, ENT physicians, paediatricians and GPs were able to develop an evidence-based document for the prevention, diagnosis and treatment of asthma and its exacerbations in Mexico.Keywords: Clinical practice guideline; Asthma; Asthmatic exacerbation; Bronchodilator; Inhaled corticosteroid; Spirometry; Immunotherapy. IntroducciónLa presentación de este documento muestra la importancia del asma en México por su alta prevalencia, pero también por su subdiagnóstico y tratamiento deficiente, que propician un mal control de los pacientes con asma, crisis más frecuentes y sintomatología activa. En consecuencia, el asma tiene un impacto socioeconómico considerable para el paciente y la sociedad en su conjunto, al igual que afecta la calidad de vida del paciente y su familia. En México, el paciente con asma puede recibir atención médica en los ámbitos pú-blico o privado, en los diferentes niveles de salud y por múltiples especialidades. Todas estas particularidades de la situación nacional indican la necesidad de un documento guía actualizado, con base amplia en múltiples gremios médicos, tanto de primer nivel de atención como de especialidad.El objetivo de la GUIMA 2017 es facilitar la reducción de la morbimortalidad por asma en México, no solo al mejorar el conocimiento acerca de esta patología, sino también al ayudar a la parte administrativa del Sector Salud a gestionar la selección y adquisición más precisa de los medicamentos necesarios para su tratamiento a nivel de la salud pública. Para tal fin se ofrecen lineamientos par...

Purpose of Review At the juncture of the COVID-19 pandemic, the world is currently in an early phase of collecting clinical data and reports of its skin manifestations, and its pathophysiology is still highly conjectural. We reviewed cutaneous manifestations associated with COVID-19 in the pediatric age group. Recent Findings Children infected by SARS-CoV-2 usually develop milder respiratory symptoms, but cutaneous manifestations seem a little more prevalent than in adults. These skin features of infection by the coronavirus can be similar to those produced by other common viruses, but there are also reports of cases with more heterogeneous clinical pictures, which have made their classification difficult. To date, the more frequently reported skin variants featured in pediatric cases are purpuric (pseudo-chilblain, necrotic-acral ischemia, hemorrhagic macules, and/or cutaneous necrosis), morbilliform/maculopapular, erythema multiforme, urticarial, vesicular, Kawasaki-like, and miscellaneous (highly variable in both frequency and severity). Their pathophysiological mechanism is still elusive and is likely to be the result of the complex involvement of one or more mechanisms, like direct virus-induced skin damage, vasculitis-like reactions, and/or indirect injury as a consequence of a systemic inflammatory reaction. Summary In this review, we presented and discussed clinical cases as examples of different cutaneous responses reported in some children with SARS-CoV-2 infection, differential diagnosis considerations, and a preliminary conceptual approach to some of their probable associated pathologic mechanisms.

Three diagnostic extracts from European manufacturers and from Mexican providers which obtain extracts in US have a <50% relative potency compared to 10,000 (B)AU/mL US extracts. Locally produced Mexican extracts have much lower total protein content and specific IgE binding capacity. These in vitro results must be complemented with other in vitro and in vivo skin prick tests to obtain a more complete picture of comparison of potency. Nevertheless results are quite consistent for the allergens tested here.

BackgroundGlobal Asthma Network (GAN) was established in 2012 as a development to the International Study of Asthma and Allergies in Childhood to improve asthma care globally.ObjectiveTo survey asthma, allergic rhinitis and atopic dermatitis in primary and secondary school children and to investigate and evaluate its prevalence, severity, management and risk factors in Mexico.MethodsGAN Phase I is a cross-sectional, multicentre survey carried out in 15 centres corresponding to 14 Mexican cities throughout 2016–2019 using the validated Spanish language version of the GAN Phase I questionnaires. The questionnaires were completed by parents of 6–7-year-old primary school pupils (school children) and by 13–14-year-old adolescents.ResultsA total of 35 780 school children and 41 399 adolescents participated. Wheezing ever prevalence was 26.2% (95% CI 25.8% to 26.7%) in school children and 23.9% (95% CI 23.4% to 24.3%) in adolescents. The corresponding frequencies for current wheeze were 10.2% (95% CI 9.9% to 10.5%) and 11.6% (95% CI 11.2% to 11.9%). In school children, the risk factors for current wheeze were rhinitis (OR 4.484; 95% CI 3.915% to 5.134%) and rash symptoms (OR 1.735; 95% CI 1.461% to 2.059%). For adolescents, rhinitis symptoms (OR 3.492; 95% CI 3.188% to 3.825%) and allergic rhinitis diagnosis (OR 2.144; 95% CI 1.787% to 2.572%) were the most significant. For both groups, there was a negative relation with centres’ sea level altitude higher than 1500 m above mean sea level (p<0.005).ConclusionsThe most important risk factors for asthma symptoms in both age groups were the presence of rhinitis and rash symptoms or diagnosis. On the other hand, sea level altitude higher than 1500 metres was a protective factor.

In a (sub)tropical country the SAR-PAR classification seems of limited value and bears poor relation with the INT-PER classification. INT is more frequent in the tropical zone. Because PER has been shown to relate to AR severity, clinical trials should select patients based on INT-PER combined with the severity cataloging because these make for a better treatment guide than SAR-PAR.