[Guidelines on atopic dermatitis for Mexico (GUIDAMEX): using the ADAPTE methodology]

With the advancement of knowledge in relation to the physiopathogenesis of atopic dermatitis (AD), several new therapeutic forms have been developed. There are also new guidelines for self-care. On the other hand, there is still an underdiagnosis of AD in Mexico. Thus, the need was seen to develop a national guide, with a broad base among the different medical groups that care for patients with AD. The Atopic Dermatitis Guidelines for Mexico (GUIDAMEX) was developed with the ADAPTE methodology, with the endorsement and participation of ten national medical societies, from physicians in Primary Healthcare to allergists and dermatologists. Throughout the manuscript, key clinical questions are answered that lead to recommendations and suggestions for the diagnosis of AD (including differential diagnosis with immunodeficiency syndromes), the recognition of comorbidities and complications, non-pharmacological treatment including therapeutic education, treatment of flares and maintenance therapy. The latter encompasses general measures to avoid triggering factors, first-line treatment focussed on repair of the skin barrier, second-line treatment (topical proactive therapy), and third-line phototherapy or systemic treatment, including dupilumab and JAK inhibitors.

[MIA 2021, Comprehensive Asthma Management. Guidelines for Mexico]

BACKGROUND

Asthma continues to be one of the most frequent chronic respiratory diseases in our country. New methods for diagnosis and treatment have been described; accordingly, the international guidelines were renewed.

OBJECTIVE

To create a national platform for the development of updated guidelines, solidly based on evidence: Comprehensive Asthma Management (Spanish acronym: MIA).

METHODS

MIA uses the ADAPTE method. The MIA development group consists of experts in pulmonology-allergology-methodology and representatives of 13 institutions and societies of specialties that manage asthma. The international reference guidelines (selected with AGREE-II): GINA 2020, GEMA 5.0, BTS/SIGN 2019 and ATS/ERS consensus document 2014-2019 on severe asthma. MIA covers suspected asthma, diagnosis, treatment, and special groups. Key clinical questions were formulated on treatment steps 1-3, biomarkers and severe asthma.

RESULTS

Based on evidence, safety, cost and local reality, the core group developed responses. Through a Delphi process the broad MIA development group suggested adjustments until consensus was reached.

CONCLUSION

A document was generated with multiple figures and algorithms, solidly based on evidence about asthma management, adjusted for Mexico with a broad base among different societies that participated in its development. It does not include guidelines for acute asthma.

Dupilumab en el tratamiento del asma

Dupilumab es un anticuerpo monoclonal humano contra receptores de interleucina (IL)-4 e IL-4/IL-13. Estas son citocinas clave en la génesis de la inflamación tipo 2, predominante en los pacientes con asma. Los ensayos clínicos que evalúan la eficacia de dupilumab incluyen tres ensayos pivotales controlados versus placebo fase 2b o 3 de 24 a 52 semanas en pacientes ≥ 12 años, con asma moderada a grave (no controlada con dosis media a alta de corticosteroides inhalados) o asma grave (dependiente de corticosteroides orales). En estos estudios, la suma de dupilumab al tratamiento se toleró adecuadamente y redujo la tasa de exacerbaciones graves, mejoró la función pulmonar, así como el control del asma y la calidad de vida, de igual forma redujo las dosis de corticosteroides sistémicos orales sin afectar el control. Dupilumab mostró eficacia en varios subgrupos de pacientes, aunque aquellos con inflamación tipo 2 mostraron un beneficio más destacado. Dupilumab está indicado (y es una opción terapéutica valiosa) en pacientes ≥ 12 años de edad que tienen asma de moderada o grave con inflamación tipo 2/fenotipo eosinofílico, descontrolada a pesar de los tratamientos convencionales o en aquellos con dependencia a corticosteroides sistémicos orales para el control.

[Food allergy, key points for clinical practice]

Food allergy is an immune reaction that occurs frequently at a pediatric age; its prevalence is higher in industrialized countries, affecting 8% of the population in average. The most frequently involved foods are: milk, chicken eggs, soy, peanuts, fish, wheat, seafood, and dried fruits. Food allergies can be divided into three groups: IgE-mediated, non-IgE-mediated, and mixed food allergy. The symptoms will depend on the immunological mechanisms and they can be divided into immediate or delayed symptoms; immediate symptoms appear during the first two hours after the intake, and delayed symptoms appear after the second hour and up to 72 hours. The diagnosis of food allergies requires the medical history of the patient, a physical examination, and laboratory tests; a misdiagnosis can lead to unnecessary elimination diets. The gold standard is the double-blind, placebo-controlled oral food challenge. The main treatment is food restriction, in which the entailed nutritional and psychological implications must be taken into account. Another treatment option is oral immunotherapy, which is recommended for patients who cannot carry out an elimination diet due to its significant impact on the quality of life.

Enhancing innate immunity against virus in times of COVID-19: Trying to untangle facts from fictions

Introduction

In 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 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 into: 1) lifestyle related (exercise, >7 h 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, etc).

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.

[Mexican consensus on fractional exhaled nitric oxide (FeNO) in asthma 2020]

The fractional exhaled nitric oxide (FeNO) is related to the level of eosinophilic inflammation in the airways and the levels of interleukin-13, as such it could be a diagnostic and monitoring tool in asthma. A working group was convened between pulmonologists, respiratory physiology experts, and allergists to establish criteria for the use of FeNO in asthma in Mexico. Through a simplified Delphi method and group discussion, seven key points regarding the use of FeNO were agreed upon. We agree that the measurement of FeNO serves for the diagnosis of asthma in specialized clinics, both in children and adults, as well as to determine the level of corticosteroid treatment. In severe asthma, we recommend FeNO for endotyping, for detecting poor therapeutic adherence, undertreatment, and the risk of crisis. We suggest FeNO can be used to determine the level of corticosteroid treatment and to identify patients at risk of loss of lung function. We also recommend it in adults to improve the selection of biological therapy and, in this context, we only suggest it in selected cases for children.

[Executive Summary of ARIA 2019: Integrated care pathways for allergic rhinitis in Argentina, Spain and Mexico]

The health and economic impact of allergic diseases are increasing rapidly, and changes in management strategies are required. Its influence reduces the capacity of work and school performance by at least a third. The ICPs of the airways (integrated care pathways for respiratory diseases) are structured multidisciplinary healthcare plans, promoting the recommendations of the guidelines in local protocols and their application to clinical practice. This document presents an executive summary for Argentina, Mexico, and Spain. Next-generation ARIA guidelines are being developed for the pharmacological treatment of allergic rhinitis (AR), using the GRADE-based guidelines for AR, tested with real-life evidence provided by mobile technology with visual analogue scales. It is concluded that in the AR treatment, H1-antihistamines are less effective than intranasal corticosteroids (INCS), in severe AR the INCS represent the first line of treatment, and intranasal combination INCS + anti-H1 is more effective than monotherapy. However, according to the MASK real-life observational study, patients have poor adherence to treatment and often self-medicate, according to their needs.

[Logistic precautions in preparation and administration of allergen immunotherapy during the COVID-19 pandemic in Mexico]

La pandemia actual de COVID-19 ha representado un reto mayúsculo para la sociedad y la comunidad médica, no solo por su alta contagiosidad sino por la variabilidad de las manifestaciones clínicas y su comportamiento impredecible bajo diferentes contextos sanitarios. Ante ello, las medidas preventivas específicas son relevantes para evitar o disminuir contagios entre pacientes y personal de las unidades de salud, considerando que el periodo presintomático durante el cual el individuo contagiado ya puede transmitir el virus varía entre cinco y seis o hasta 14 días, según datos de la Organización Mundial de la Salud. Además, un paciente infectado puede estar asintomático, incluso, algunas personas después de haber padecido COVID-19 pueden continuar expulsando virus por algunos días más después de recuperarse.

[MASK (Mobile Airways Sentinel Network), a mobile App with ARIA's comprehensive solution in Spanish-speaking countries]

Although there are high quality clinical guidelines about allergic rhinitis, many patients receive deficient treatment, partly due to the high level of self-medication. MASK (Mobile Airways Sentinel Network) is an integral part of a project against chronic diseases which it is focused on active and healthy aging and is supported by the European Union. It forms the third phase of ARIA (Allergic Rhinitis and its Impact on Asthma) in which, through a mobile app on a smart device, the purpose is to guide patients in the control of their multimorbidity, allergic rhinitis or conjunctivitis, or asthma. The "Allergy Diary" app by MACVIA-ARIA is free and it is available for Android and iOS; on it, patients indicate how unpleasant the symptoms are on a daily basis through five screens with an analogous visual scale; two more screens were recently added (sleep affectation). With the app, it is also possible to download the information of the "Allergy Diary" on the physician's computer through a QR code at the moment of the medical consultation. In this article, we review the first year of experience in Spain, Mexico and Argentina, where the Spanish version is used.

[GUIMIT 2019, Mexican Guideline on Immunotherapy. Guideline on the diagnosis of IgE-mediated allergic disease and immunotherapy following the ADAPTE approach]

BACKGROUND

In Mexico, allergen immunotherapy (AIT) and immunotherapy with hymenoptera venom (VIT) is traditionally practiced combining aspects of the European and American school. In addition, both types of extracts (European and American) are commercially available in Mexico. Moreover, for an adequate AIT/VIT a timely diagnosis is crucial. Therefore, there is a need for a widely accepted, up-to-date national immunotherapy guideline that covers diagnostic issues, indications, dosage, mechanisms, adverse effects and future expectations of AIT (GUIMIT 2019).

METHOD

With nationwide groups of allergists participating, including delegates from postgraduate training-programs in Allergy/Immunology-forming, the guideline document was developed according to the ADAPTE methodology: the immunotherapy guidelines from European Academy of Allergy and Clinical Immunology, German Society for Allergology and Clinical Immunology, The American Academy of Allergy, Asthma and Immunology and American College of Allergy, Asthma, and Immunology were selected as mother guidelines, as they received the highest AGREE-II score among international guidelines available; their evidence conforms the scientific basis for this document.

RESULTS

GUIMIT emanates strong or weak (suggestions) recommendations about practical issues directly related to in vivo or in vitro diagnosis of IgE mediated allergic diseases and the preparation and application of AIT/VIT and its adverse effects. GUIMIT finishes with a perspective on AIT modalities for the future. All the statements were discussed and voted on until > 80 % consensus was reached.

CONCLUSIONS

A wide and diverse group of AIT/VIT experts issued transculturized, evidence-based recommendations and reached consensus that might improve and standardize AIT practice in Mexico.

Low Salivary Amylase Gene (AMY1) Copy Number Is Associated with Obesity and Gut Prevotella Abundance in Mexican Children and Adults

Genome-wide association studies (GWAS) have identified copy number variants (CNVs) associated with obesity in chromosomal regions 1p31.1, 10q11.22, 11q11, 16p12.3, and recently 1p21.1, which contains the salivary amylase gene (AMY1). Recent evidence suggests this enzyme may influence gut microbiota composition through carbohydrate (mainly starch) degradation. The role of these CNVs in obesity has been scarcely explored in the Latino population, and thus the aim of our study was to evaluate the association of 1p31.1, 10q11.22, 11q11, 16p12.3 and 1p21.1 CNVs with obesity in 921 Mexican children, to replicate significant associations in 920 Mexican adults, and to analyze the association of AMY1 copy number with gut microbiota in 75 children and 45 adults. Of the five CNVs analyzed, 1q11 CNV was significantly associated with obesity in children, but not in adults. Only AMY1 CNV was significantly associated with obesity in both age groups. Moreover, gut microbiota analyses revealed a positive correlation between AMY1 copy number and Prevotella abundance. This genus has enzymes and gene clusters essential for complex polysaccharide degradation and utilization. To our knowledge, this is the first study to analyze the association of these five CNVs in the Mexican population and to report a correlation between AMY1 CN and gut microbiota in humans.

A novel approach for human whole transcriptome analysis based on absolute gene expression of microarray data

Background

In spite of the emergence of RNA sequencing (RNA-seq), microarrays remain in widespread use for gene expression analysis in the clinic. There are over 767,000 RNA microarrays from human samples in public repositories, which are an invaluable resource for biomedical research and personalized medicine. The absolute gene expression analysis allows the transcriptome profiling of all expressed genes under a specific biological condition without the need of a reference sample. However, the background fluorescence represents a challenge to determine the absolute gene expression in microarrays. Given that the Y chromosome is absent in female subjects, we used it as a new approach for absolute gene expression analysis in which the fluorescence of the Y chromosome genes of female subjects was used as the background fluorescence for all the probes in the microarray. This fluorescence was used to establish an absolute gene expression threshold, allowing the differentiation between expressed and non-expressed genes in microarrays.

Methods

We extracted the RNA from 16 children leukocyte samples (nine males and seven females, ages 6-10 years). An Affymetrix Gene Chip Human Gene 1.0 ST Array was carried out for each sample and the fluorescence of 124 genes of the Y chromosome was used to calculate the absolute gene expression threshold. After that, several expressed and non-expressed genes according to our absolute gene expression threshold were compared against the expression obtained using real-time quantitative polymerase chain reaction (RT-qPCR).

Results

From the 124 genes of the Y chromosome, three genes (DDX3Y, TXLNG2P and EIF1AY) that displayed significant differences between sexes were used to calculate the absolute gene expression threshold. Using this threshold, we selected 13 expressed and non-expressed genes and confirmed their expression level by RT-qPCR. Then, we selected the top 5% most expressed genes and found that several KEGG pathways were significantly enriched. Interestingly, these pathways were related to the typical functions of leukocytes cells, such as antigen processing and presentation and natural killer cell mediated cytotoxicity. We also applied this method to obtain the absolute gene expression threshold in already published microarray data of liver cells, where the top 5% expressed genes showed an enrichment of typical KEGG pathways for liver cells. Our results suggest that the three selected genes of the Y chromosome can be used to calculate an absolute gene expression threshold, allowing a transcriptome profiling of microarray data without the need of an additional reference experiment.

Discussion

Our approach based on the establishment of a threshold for absolute gene expression analysis will allow a new way to analyze thousands of microarrays from public databases. This allows the study of different human diseases without the need of having additional samples for relative expression experiments.

Ozone exposure, vitamin C intake, and genetic susceptibility of asthmatic children in Mexico City: a cohort study

Background

We previously reported that asthmatic children with GSTM1 null genotype may be more susceptible to the acute effect of ozone on the small airways and might benefit from antioxidant supplementation. This study aims to assess the acute effect of ozone on lung function (FEF_25-75) in asthmatic children according to dietary intake of vitamin C and the number of putative risk alleles in three antioxidant genes: GSTM1, GSTP1 (rs1695), and NQO1 (rs1800566).

Methods

257 asthmatic children from two cohort studies conducted in Mexico City were included. Stratified linear mixed models with random intercepts and random slopes on ozone were used. Potential confounding by ethnicity was assessed. Analyses were conducted under single gene and genotype score approaches.

Results

The change in FEF_25-75 per interquartile range (60 ppb) of ozone in persistent asthmatic children with low vitamin C intake and GSTM1 null was −91.2 ml/s (p = 0.06). Persistent asthmatic children with 4 to 6 risk alleles and low vitamin C intake showed an average decrement in FEF_25-75 of 97.2 ml/s per 60 ppb of ozone (p = 0.03). In contrast in children with 1 to 3 risk alleles, acute effects of ozone on FEF_25-75 did not differ by vitamin C intake.

Conclusions

Our results provide further evidence that asthmatic children predicted to have compromised antioxidant defense by virtue of genetic susceptibility combined with deficient antioxidant intake may be at increased risk of adverse effects of ozone on pulmonary function.

Factors associated with allergic rhinitis in children and adolescents from northern Mexico: International Study of Asthma and Allergies in Childhood Phase IIIB

The epidemiology of allergic diseases has not been studied extensively in Mexico. The present study, based on the International Study of Asthma and Allergies in Childhood Phase IIIB survey, reports the prevalence of allergic rhinitis and the associated risk factors in the pediatric population in four cities in northern Mexico. Children (6-7 years old) and adolescents (13-14 years old) in public elementary and secondary schools were surveyed in 2002 and 2003. The subjects were chosen randomly from Ciudad Victoria, Mexicali, Monterrey, and Tijuana. The following categories were analyzed: occurrence of rhinitis symptoms (currently or in the last 12 months), rhinoconjunctivitis symptoms, a previous diagnosis of allergic rhinitis, and relevant environmental factors. Factors associated with rhinitis that were identified previously with the chi-squared test were analyzed using logistic regression. The number of valid questionnaires was 10,892 for schoolchildren and 12,299 for adolescents. In 6- to 7-year-old children, the following frequencies were determined: rhinitis (ever), 27.9%; current rhinitis, 24.2%; rhinoconjunctivitis, 9.2%; and diagnosis of allergic rhinitis, 5.5%. The corresponding frequencies in 13- to 14-year-old children were 33.3, 34.1, 18.4, and 3.8%. In both 6- to 7-year-old and 13- to 14-year-old children, all rhinitis items were associated with asthma symptoms, dermatitis symptoms, paracetamol consumption, and maternal smoking (odds ratio, >1; p < 0.05). The main risk factors associated with allergic rhinitis symptoms in children and adolescents from cities in northern Mexico were other allergic conditions, paracetamol consumption, and passive smoking.

Increased levels of outdoor air pollutants are associated with reduced bronchodilation in children with asthma

BACKGROUND

Increased outdoor air pollution levels are associated with more frequent use of rescue inhalers in subjects with asthma. However, it is unknown whether this phenomenon is explained by an air pollution-mediated increase in respiratory symptom severity or whether air pollutants decrease the efficacy of short-acting beta-agonists (SABAs).

METHODS

We examined the relationship between the percentage change in FEV(1) after SABA use with outdoor air pollution exposure in 85 children with asthma who were 7 to 12 years of age. Outdoor air pollution exposure was determined by measuring nitrogen dioxide (NO(2)), ozone (O(3)), and fine particulate matter (ie, particulate matter with an aerodynamic diameter < 2.5 microm [PM(2.5)]) levels. These measurements were obtained from the Mexico City Automated Monitoring Network from network sites located within a 5-km radius of each child's home and school.

RESULTS

We found that a same-day interquartile increase of 10 parts per billion (ppb) in NO(2) concentration was associated with a reduced response of FEV(1) to SABA therapy (-15%; 95% CI, -29 to -0.5). This association was also significant when considering NO(2) levels in each of the preceding 3 days. An interquartile O(3) increase (16 ppb) in the preceding fifth day was associated with a reduced response to SABA (-11%; 95% CI, -23 to -1); an interquartile PM(2.5) increase (14 microg/m(3)) was not associated with any significant reductions in the response to SABA therapy. These associations were not observed in children receiving therapy with inhaled corticosteroids.

CONCLUSIONS

Our results suggest that recent exposure to NO(2) and possibly O(3) may reduce the response to SABAs in producing bronchodilation in children with asthma. The association between NO(2) and FEV(1) response to SABA administration may have important implications in understanding how outdoor air pollution levels relate to asthma control.

Co-administration of salbutamol and fluticasone for emergency treatment of children with moderate acute asthma

This study aimed to compare the efficacy of nebulized therapy with salbutamol alone or in combination with fluticasone. In a randomized, double-blind clinical trial, 150 children with moderate acute asthma were randomly assigned to receive by nebulizations either (i) three doses of salbutamol 30 microl/kg per dose, each dose administered every 15 min, (ii) three doses of salbutamol plus two doses of fluticasone 500 microg/dose at 15 and 30 min after first dose of salbutamol, or (iii) three doses of salbutamol/fluticasone 500 microg/dose, each combined dose administered every 15 min. Pulse oxymetry (SaO2), peak expiratory flow (PEF) and Wood et al. (Am J Dis Child, 123, 1972, 123) clinical scale were evaluated at baseline, 15, 30, 45, 60, 90 and 120 min after the first nebulization. Patients in the three groups significantly improved since 15 min after the first nebulization. We did not observe differences in the recovery of SaO2 and PEF among the three groups of treatment (p > 0.10). In group 3, children showed better clinical response at 120 min than the other two groups (p < 0.05). No significant adverse effects were observed with any treatment. To summarize, in children with acute moderate asthma, nebulized salbutamol at an accumulated dose of 90 mul/kg plus fluticasone at an accumulated dose of 1500 microg produced better clinical relief after 2 h. However, similar PEF and SaO2 responses were observed with salbutamol alone or in combination with different doses of fluticasone.

Cyclophosphamide Hypersensitivity in a Leukemic Child

Although hypersensitivity reactions to chemotherapeutic drugs have rarely been reported, they may occur with any of these agents. A Mexican native 44-kg 13-year-old boy suffering from acute lymphoblastic leukemia (ALL) received chemotherapy for 7 years. Three years later, a recurrence of ALL was detected in his right testicle. The patient was scheduled to receive 12 weekly cycles of 50 mg/kg of cyclophosphamide (CPM) as a 1-hour intravenous infusion. The patient did not have any history of drug allergies or any other type of ADR. Immediately after the fourth cycle of CPM, the patient developed itchy, maculopapular rash, sweating, respiratory distress, and anxiety. According to the algorithm developed by Naranjo et al, the ADR was classified as probably secondary to CPM. Skin tests were negative to hypersensitivity to CPM, and a new cycle of CPM was administered. However, the patient developed a similar hypersensitivity reaction to CPM. After an analysis of the clinical course of the ADR and the need to continue the chemotherapeutic treatment with CPM, we decided to desensitize the patient to this drug. Total duration of the procedure was 5 hours and was performed on only 1 occasion. The program of 12 cycles of chemotherapy was successfully completed without any sign or symptom of hypersensitivity to CPM. In conclusion, we have reported a case of hypersensitivity to CPM who was successfully desensitized to CPM.