[The clinical practice of allergen immunotherapy in Mexico according to 277 allergists who were surveyed during a three-year AIT course]

BACKGROUND

There are different guidelines for the diagnosis of allergic diseases and the application of allergen immunotherapy (AIT).

OBJECTIVE

To describe how Mexican allergists diagnose and treat respiratory and food allergies with AIT.

METHODS

227 allergists who attended an immunotherapy symposium were surveyed; the topics investigated were the daily practices in the diagnosis of respiratory and food allergies, as well as ways to apply AIT.

RESULTS

The surveyed allergists use skin prick tests for the diagnosis of both respiratory and food allergies in 100 % and 87.7 % of their cases respectively; in vitro diagnosis through serum specific IgE in 55.5 % and 63 %, and molecular diagnostics in 14.1% and 13.2 %. For aeroallergens, 81 % prescribe subcutaneous AIT, 77.9 % use liquid sublingual AIT, and 1.8 % prefer SLIT in tablets; however, 45 % indicated that they would use tablets in the future. Regarding food allergens, most respondents did not prescribe AIT; however, 55% of them are interested in oral AIT and 59% of them are interested in sublingual AIT.

CONCLUSIONS

Generally, the diagnosis and treatment of allergic diseases are carried out according to international guidelines; besides, the interviewed allergists expressed flexibility to adopt new schemes.

Coronavirus disease 2019, allergic diseases, and allergen immunotherapy: Possible favorable mechanisms of interaction

Background: Both, allergen immunotherapy (AIT) and SARS-COV-2 infection cause a set of immunologic changes that respectively vary during the course of the treatment or the disease. Objective: To review immune changes brought along by each of these entities and how they might interrelate. Methods: We start presenting a brief review of the structure of the new coronavirus and how it alters the functioning of the human immune system. Subsequently, we describe the immune changes induced by AIT and how these changes could be favorable or unfavorable in the allergic patient infected with SARS-CoV-2 at a particular point of time during the evolving infection. Results: We describe how a healthy immune response against SARS-CoV-2 develops, versus an immune response that is initially suppressed by the virus, but ultimately overactivated, leading to an excessive production of cytokines (cytokine-storm-like). These changes are then linked to the clinical manifestations and outcomes of the patient. Reviewing the immune changes secondary to AIT, it becomes clear how AIT is capable of restoring a healthy innate immunity. Investigators have previously shown that the frequency of respiratory infections is reduced in allergic patients treated with AIT. On the other hand it also increases immunoregulation. Conclusion: As there are many variables involved, it is hard to predict how AIT could influence the allergic patient's reaction to a SARS-CoV-2 infection. In any case, AIT is likely to be beneficial for the patient with allergic rhinitis and/or allergic asthma in the context of the SARS-CoV-2 pandemic as controlling allergic diseases leads to a reduced need for contact with healthcare professionals. The authors remind the reader that everything in this article is still theoretical, since at the moment, there are no published clinical trials on the outcome of COVID-19 in allergic patients under AIT.

Cutaneous Manifestations Related to COVID-19 Immune Dysregulation in the Pediatric Age Group

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.

Global Asthma Network Phase I study in Mexico: prevalence of asthma symptoms, risk factors and altitude associations-a cross-sectional study

Background

Global 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.

Objective

To 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.

Methods

GAN 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.

Results

A 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).

Conclusions

The 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.

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.

Compromising between European and US allergen immunotherapy schools: Discussions from GUIMIT, the Mexican immunotherapy guidelines

Background

Allergen immunotherapy (AIT) has a longstanding history and still remains the only disease-changing treatment for allergic rhinitis and asthma. Over the years 2 different schools have developed their strategies: the United States (US) and the European. Allergen extracts available in these regions are adapted to local practice. In other parts of the world, extracts from both regions and local ones are commercialized, as in Mexico. Here, local experts developed a national AIT guideline (GUIMIT 2019) searching for compromises between both schools.

Methods

Using ADAPTE methodology for transculturizing guidelines and AGREE-II for evaluating guideline quality, GUIMIT selected 3 high-quality Main Reference Guidelines (MRGs): the European Academy of Allergy, Asthma and Immunology (EAACI) guideines, the S2k guideline of various German-speaking medical societies (2014), and the US Practice Parameters on Allergen Immunotherapy 2011. We formulated clinical questions and based responses on the fused evidence available in the MRGs, combined with local possibilities, patient's preference, and costs. We came across several issues on which the MRGs disagreed. These are presented here along with arguments of GUIMIT members to resolve them. GUIMIT (for a complete English version, Supplementary data) concluded the following.

Results

Related to the diagnosis of IgE-mediated respiratory allergy, apart from skin prick testing complementary tests (challenges, in vitro testing and molecular such as species-specific allergens) might be useful in selected cases to inform AIT composition. AIT is indicated in allergic rhinitis and suggested in allergic asthma (once controlled) and IgE-mediated atopic dermatitis. Concerning the correct subcutaneous AIT dose for compounding vials according to the US school: dosing tables and formula are given; up to 4 non-related allergens can be mixed, refraining from mixing high with low protease extracts. When using European extracts: the manufacturer's indications should be followed; in multi-allergic patients 2 simultaneous injections can be given (100% consensus); mixing is discouraged. In Mexico only allergoid tablets are available; based on doses used in all sublingual immunotherapy (SLIT) publications referenced in MRGs, GUIMIT suggests a probable effective dose related to subcutaneous immunotherapy (SCIT) might be: 50-200% of the monthly SCIT dose given daily, maximum mixing 4 allergens. Also, a table with practical suggestions on non-evidence-existing issues, developed with a simplified Delphi method, is added. Finally, dissemination and implementation of guidelines is briefly discussed, explaining how we used online tools for this in Mexico.

Conclusions

Countries where European and American AIT extracts are available should adjust AIT according to which school is followed.

[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.

[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.

[Mexican Asthma Guidelines: GUIMA 2017]

BACKGROUND

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.

CONCLUSIONS

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.

Allergen sensitization linked to climate and age, not to intermittent-persistent rhinitis in a cross-sectional cohort study in the (sub)tropics

BACKGROUND

Allergen 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.

METHODS

In 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.

RESULTS

628 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).

CONCLUSIONS

In 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.

[Mexican clinical practice guidelines of immunotherapy 2011]

BACKGROUND

Several international guidelines on immunotherapy exist, but they only apply partially in Mexico. The Mexican guideline of immunotherapy dates from 1998.

OBJECTIVES

To establish clinical recommendations and suggestions for Allergy residents and specialists for skin testing and allergen immunotherapy based on evidence and Mexican expert opinion, according to the GRADE system.

METHODS

The guidelines were developed following the methodology of a guideline for clinical practice starting with the formulation of clinical questions, in the context of Mexican environmental conditions and morbidity, with the participation of allergists from all regions of the country. External validation was obtained. Its development followed three steps: 1. formulation of 24 clinical questions. 2. Search for consensus on the answers among members of the Regional chapters of both Mexican Colleges of Allergists (CMICA and COMPEDIA) during regional meetings. 3. Literature search for articles related to the questions and grading of its quality according to GRADE.

RESULTS

Based on the regional consensus, 116 articles and the safety, patient acceptance/ comfort and cost clinical recommendations and suggestions were developed on basic aspects of skin testing, subcutaneous and sublingual immunotherapy (patient preparation, vial preparation and application schedules) and the treatment of eventual adverse reactions.

CONCLUSIONS

A clinical guideline was developed respecting particular methodology, validated by CMICA and COMPEDIA for its implementation among Mexican allergists. Several aspects deserve further study to improve scientific evidence.

KEYWORDS

Allergen immunotherapy, subcutaneous immunotherapy, sublingual immunotherapy, skin testing, allergy diagnosis, rhinitis, asthma, atopic dermatitis, house dust mite, pollens, anaphylaxis, adrenaline, Mexico.

New CD3zeta allele showing a 9-bp deletion in the 3'-UT region of the gene

We report here a non-previously described 9-bp deletion in the 3'-UT region of the CD3zeta gene, located in between two AREs.

New types of immunotherapy in children

Injection immunotherapy has been shown to be particularly beneficial in treating allergic rhinitis, mild to moderate asthma, and anaphylaxis caused by bee and wasp venom. It also produces a long-term, antigen-specific, protective immune effect and is the only treatment that offers the possibility of reducing the risk of asthma development in children with allergic rhinitis. Nonetheless, the potentially severe side effects associated with this form of immunotherapy limit its widespread use. Diverse preparations are being developed to increase its safety and improve its efficacy. These include alternative routes of administration, particularly the sublingual route; use of novel adjuvants, such as CpG oligonucleotides and mycobacterial vaccines; and other approaches, such as peptide immunotherapy, recombinant allergens, DNA vaccination, and combined therapy. Some of these immunotherapy forms have been evaluated in children.

Frequency of acute systemic reactions in patients with allergic rhinitis and asthma treated with sublingual immunotherapy

BACKGROUND

Several studies have demonstrated the efficacy and safety of sublingual immunotherapy in the treatment of respiratory allergy.

OBJECTIVE

To determine the frequency of systemic adverse reactions in patients treated with standardized extracts of sublingual immunotherapy.

METHODS

Allergic patients with rhinitis with or without asthma and sensitized to at least 1 allergen were included. Increasing doses of standardized allergens were administered until reaching an average dose accumulated of 7,200 U after 26 weeks of treatment. Adverse events were graded according to the European Academy of Allergy and Clinical Immunology immunotherapy position paper.

RESULTS

Forty-three patients with a median age of 11 years (interquartile range, 8-20 years) were included. All the patients had allergic rhinitis, and 63% had asthma; they were sensitized mostly to Dermatophagoides pteronyssinus and Dermatophagoides farinae. Four patients (9%) presented with an immediate and 1 (2%) with a late systemic reaction. In total, 7 systemic reactions occurred in 23,154 doses, and all were associated with wheezing or worsening of nasal symptoms (grade 2); in addition, 1 patient had angioedema and urticaria (grade 3).

CONCLUSIONS

In this group, systemic reaction frequency was 11.6%, and all were classified as grade 2 or 3. Further assessments in larger samples of patients are required in the context of randomized controlled trials.