The importance of the microbiome, and of the gut-lung axis in the origin and persistence of asthma, is an ongoing field of investigation. The process of microbial colonisation in the first three years of life is fundamental for health, with the first hundred days of life being critical. Different factors are associated with early microbial dysbiosis, such as caesarean delivery, artificial lactation and antibiotic therapy, among others. Longitudinal cohort studies on gut and airway microbiome in children have found an association between microbial dysbiosis and asthma at later ages of life. A low α-diversity and relative abundance of certain commensal gut bacterial genera in the first year of life are associated with the development of asthma. Gut microbial dysbiosis, with a lower abundance of Phylum Firmicutes, could be related with increased risk of asthma. Upper airway microbial dysbiosis, especially early colonisation by Moraxella spp., is associated with recurrent viral infections and the development of asthma. Moreover, the bacteria in the respiratory system produce metabolites that may modify the inception of asthma and is progression. The role of the lung microbiome in asthma development has yet to be fully elucidated. Nevertheless, the most consistent finding in studies on lung microbiome is the increased bacterial load and the predominance of proteobacteria, especially Haemophilus spp. and Moraxella catarrhalis. In this review we shall update the knowledge on the association between microbial dysbiosis and the origins of asthma, as well as its persistence, phenotypes, and severity.

Background: The relationship between parent-reported and measured height and weight is not well established in schoolchildren. This relationship has never been studied in asthmatic children. The objective of this study is to test the validity of the parent-reported weight and height for defining obesity by BMI and to know whether the perception of this height and weight changes when the child suffers from asthma. Methods: All classes of children of the target ages of 6–8 years (n = 1,672, participation rate 70.2%) of all schools in four municipalities of Murcia (Spain) were included. Parents were asked about their children’s weight and height using a questionnaire which included the International Study of Asthma and Allergies in Childhood (ISAAC) core questions on asthma. Parents were not aware that their children were going to be weighed and measured within 1 week’s time. Measurements were performed using a rigid stadiometer to the nearest 0.1 cm and a scale to the nearest 0.1 kg. Results: The bias (reported minus real) was, respectively, for nonasthmatics and asthmatics: weight +0.42 kg (95% CI +0.24; +0.59 kg) versus +0.97 kg (+0.50; +1.44 kg), height +2.37 cm (+2.06; +2.68 cm) versus +2.87 cm (+1.87; +3.87 cm); BMI –0.39 kg/m2 (–0.52; –0.23 kg/m2) versus –0.23 kg/m2 (–0.58; +0.13 kg/m2). Diagnostic accuracy of obesity calculated from reported measurements was, respectively, for nonasthmatics and asthmatics: sensitivity 78.0 versus 77.8%, specificity 96.2 versus 94.5%, positive predictive value 77.2 versus 73.7% and negative predictive value 96.4 versus 91.7%. Conclusions: Reported weights and heights had large biases, comparable between parents of both asthmatic and those of nonasthmatic children. However, this information could be reasonably valid for classifying children as obese or nonobese in large epidemiological studies.

Background: There seems to be an association between paracetamol consumption during late pregnancy and the prevalence of wheezing in infancy and childhood. The aim of the present study is to determine whether the aforementioned association is modified by the presence of asthma in the mother. Methods: A total of 1,741 children aged 3–5 years from an epidemiological survey performed in the province of Murcia (Spain) were included in the analysis. Data on paracetamol consumption (never, at least once during pregnancy or at least once per month during pregnancy), wheezing symptoms in the offspring (according to the International Study of Asthma and Allergies in Childhood protocol) and the presence of asthma in the mother, together with other known risk factors for asthma, were obtained by means of a questionnaire. Results: The mean age of the children was 4.08 ± 0.8 years and 51.1% were males. The overall prevalence of current wheezing was 20.2%. The frequency of paracetamol usage was similar among asthmatic and non-asthmatic mothers, and only a small proportion of them took this drug at least once a month (13.8% of asthmatics and 11.0% of non-asthmatics). Compared to the mothers who never took paracetamol, there was a significant association between the mother having taken paracetamol at least once per month during pregnancy and the offspring suffering from wheezing at preschool age, but only among non-asthmatic mothers (odds ratio 1.94, 95% confidence interval 1.34–2.79 vs. odds ratio 1.05, 95% confidence interval 0.21–5.08). This association was maintained after controlling for potential confounders (odds ratio 1.74, 95% confidence interval 1.15–2.61). Conclusions: The frequent usage of paracetamol during pregnancy is associated with the prevalence of wheezing in offspring during preschool years. Asthma in the mother might modify this association.

Recognition of phenotypic variability in pediatric asthma allows for a more personalized therapeutic approach. Knowledge of the underlying pathophysiological and molecular mechanisms (endotypes) of corresponding biomarkers and new treatments enables this strategy to progress. Biologic therapies for children with severe asthma are becoming more relevant in this sense. The T2 phenotype is the most prevalent in childhood and adolescence, and non-T2 phenotypes are usually rare. This document aims to review the mechanism of action, efficacy, and potential predictive and monitoring biomarkers of biological drugs, focusing on the pediatric population. The drugs currently available are omalizumab, mepolizumab, benralizumab, dupilumab, and 1ezepelumab, with some differences in administrative approval prescription criteria between the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Previously, we described the characteristics of severe asthma in children and its diagnostic and therapeutic management.

All guidelines, protocols and recommendations underline the importance of therapeutic education as a key element in asthma management and control. Considerable evidence supports the efficacy and effectiveness of this measure. Health personnel, as well as patients and their parents, can and should be educated with two main objectives: to achieve the best possible quality of life and to allow self control of the disease. These goals can be attained through an educational process that should be individually tailored, continuous, progressive, dynamic, and sequential. The process poses more than a few difficulties involving patients, health professionals, and the health systems. Knowledge of the various psychological factors that can be present in asthmatic patients, as well as the factors related to the highly prevalent phenomenon of non-adherence, is essential. Awareness of the factors influencing physician-patient-family communication is also highly important to achieve the objectives set in therapeutic education. The educational process helps knowledge and abilities to be acquired and allows attitudes and beliefs to be modified. Patients and caregivers should be provided with an individual written action plan based on symptoms and/or forced expiratory volume in 1 second. Periodic follow-up visits are also required.