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.

[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.

[Clinical-epidemiological profile of oral allergy syndrome in the population aged 6 to 18 years]

BACKGROUND

Oral allergy syndrome (OAS) or pollen-fruit syndrome is a type of food allergy. Its characteristics and associated allergens vary according to the studied population. There are few studies in Mexico about this topic, none in children.

OBJECTIVE

To describe clinical and epidemiological characteristics of OAS among children in Mexico.

METHODS

A descriptive, observational, transversal and prospective study was conducted. We included every patient from 6 to 18 years old with diagnostic suspicion of OAS, in which complete clinical history, skin test to food and pollens, and oral food challenge were performed.

RESULTS

We found a prevalence of 5.3% (29 patients): 55% were males. Average age was 10 ± 3 years, and average number of food implicated were 6.8 ± 4.1. Apple, peach and banana, were the most frequent food associated, and sensitization to oak and European privet, the more prevalent pollens found in OAS.

CONCLUSION

OAS is a common type of food allergy, transient and mild in nature. In more than 90% of the cases is associated with allergic rhinitis and sensitization to pollens. In our population, profilins may be involved in its pathogenesis. However, more studies are required to prove this.

Perfil clínico-epidemiológico de pacientes con sospecha de alergia alimentaria en México. Estudio Mexipreval

Antecedentes: las enfermedades alérgicas asociadas con alimentos se incrementan anualmente. Tienen una prevalencia de 2 a 4% en adultos y de 6 a 8% en niños. El cuadro clínico varía de síntomas leves hasta reacciones anafilácticas. El diagnóstico se basa en la historia clínica, pero debe demostrarse evidencia de sensibilización específica para el alergeno.Objetivo: conocer el perfil clínico-epidemiológico de los pacientes con sospecha de alergia alimentaria vistos en consultorios médicos (alergólogos y no alergólogos), así como la conducta diagnóstica y tratamiento habitual.Material y método: estudio observacional, transversal y descriptivo, efectuado en consultorios de médicos que atienden pacientes con alergia alimentaria en la República Mexicana durante un año natural de abril de 2013 a marzo de 2014, mediante un muestreo por conveniencia.Resultados: se realizaron 1,971 encuestas. No se encontró diferencia en relación con el género. En relación con la edad, se reportó una distribución bimodal, con picos a los 2 y 35 años de edad. Había antecedente de alergia respiratoria en 75% de los casos. El 80% de los pacientes tuvo algún síntoma antes de buscar atención y las manifestaciones clínicas más frecuentes afectaron la piel (57.1%). El 5% refirió haber padecido al menos un evento de anafilaxia.Conclusión: el tipo de alimento implicado cambia con la edad. La forma de manifestación clínica más frecuente fue la cutánea, pero varía con el tipo de alimento. Aun cuando la sospecha clínica sea alta, deben utilizarse métodos específicos que confirmen el diagnóstico.