Severe and Difficult Asthma: Diagnosis and Management—Challenges for a Low-Resource Environment

Severe and difcult asthma in a low- and middle-income country (LMIC) can relate to (a) lack of availability of basic medications; (b) potentially reversible factors such as poor adherence or comorbidities such as obesity inhibiting a good response to treatment; and (c) (rarely) true severe, therapy-resistant asthma. However, defnitions of severity should encompass not merely doses of prescribed medication, but also underlying risk. The nature of asthmatic airway disease shows geographical variation, and LMIC asthma should not be assumed to be phenotypically the same as that in high-income countries (HICs). The frst assessment step is to ensure another diagnosis is not being missed. Largely, political action is needed if children with asthma are to get access to basic medications. If a child is apparently not responding to low dose, simple medications, the next step is not to increase the dose but perform a detailed assessment of what factors (for example co-morbidities such as obesity, or social factors like poor adherence) are inhibiting a treatment response; in most cases, an underlying reason can be found. An assessment of risk of future severe asthma attacks, side-efects of medication and impaired lung development is also important. True severe, therapy-resistant asthma is rare and there are multiple underlying molecular pathologies. In HICs, steroid-resistant eosinophilia would be treated with omalizumab or mepolizumab, but the cost of these is prohibitive in LMICs, the biomarkers of successful therapy are likely only relevant to HICs. In LMICs, a raised blood eosinophil count may be due to parasites, so treating asthma based on the blood eosinophil count may not be appropriate in these settings.

Adverse early-life environmental exposures and their repercussions on adult respiratory health

Abstract Objective: To review in the literature the environmental problems in early life that impact the respiratory health of adults. Sources: Non-systematic review including articles in English. Search filters were not used in relation to the publication date, but the authors selected mainly publications from the last five years. Summary of the findings: In this review, the authors present the exposure pathways and how the damage occurs depending on the child's stage of development; the authors describe the main environmental pollutants - tobacco smoke, particulate matter, air pollution associated with traffic, adverse childhood experiences and socioeconomic status; the authors present studies that evaluated the repercussions on the respiratory system of adults resulting from exposure to adverse environmental factors in childhood, such as increased incidence of Chronic Obstructive Pulmonary Disease (COPD), asthma and allergies; and, a decline in lung function. The authors emphasize that evidence demonstrates that adult respiratory diseases almost always have their origins in early life. Finally, the authors emphasize that health professionals must know, diagnose, monitor, and prevent toxic exposure among children and women. Conclusion: The authors conclude that it is necessary to recognize risk factors and intervene in the period of greatest vulnerability to the occurrence of harmful effects of environmental exposures, to prevent, delay the onset or modify the progression of lung disease throughout life and into adulthood.

Opciones terapéuticas en el asma infantil / Therapeutical options of childhood asthma

Es importante identificar a los niños sensibles a esteroides de aquellos que no requieren tratamiento. En particular, el reconocer que existen fenotipos que no requieren corticoides debería impedir un escalamiento de la terapia, con todos los riesgos concomitantes de ésta estrategia.

Fenotipos del asma infantil / Asthma phenotypes in childhood

Estudios prospectivos sugieren que hasta el 50 por ciento de los niños sibilan en la etapa preescolar. Sería absurdo sugerir que todos tienen inflamación eosinofílica de la vía aérea y que todos necesitan terapia con corticoides inhalados. Seguramente es prioritario un análisis crítico de los fenotipos. Las diferentes condiciones fenotípicas no son mutuamente excluyentes y si coexisten de hecho en un solo individuo, las contribuciones relativas podrían ser difíciles de identificar. El reconocimiento de las distintas categorías no ha sido posible hasta ahora debido al sesgo en la selección. La mayoría de los niños tienen cuadros virales asociados a sibilancia o asma persistente. Sin embargo, los fenotipos intermedios suelen confundir el panorama, y en última instancia puede ser necesario un ensayo terapéutico para determinar el mejor tratamiento en ese niño.