Endotypes of Paediatric Cough-Do They Exist and Finding New Techniques to Improve Clinical Outcomes

Chronic cough is a common symptom of many childhood lung conditions. Given the phenotypic heterogeneity of chronic cough, better characterization through endotyping is required to provide diagnostic certainty, precision therapies and to identify pathobiological mechanisms. This review summarizes recent endotype discoveries in airway diseases, particularly in relation to children, and describes the multi-omic approaches that are required to define endotypes. Potential biospecimens that may contribute to endotype and biomarker discoveries are also discussed. Identifying endotypes of chronic cough can likely provide personalized medicine and contribute to improved clinical outcomes for children.

Cough Hypersensitivity Syndrome: Why Its Use Is Inappropriate in Children

In children and adults, chronic cough is a common symptom presenting to health professionals worldwide. It is internationally accepted that children with chronic cough should be managed with pediatric specific management guidelines. The newly proposed clinical entity of 'cough hypersensitivity syndrome' has gained significant attention in adult literature. Given the significant differences between childhood and adult chronic cough, including in respiratory physiology and anatomy, and cough sensitivity, we address the suitability of the use of cough hypersensitivity syndrome in children. We explore these differences between childhood and adult chronic cough, explain what cough hypersensitivity is and highlight why the term cough hypersensitivity syndrome should not be used in children.

Plasma Extracellular Vesicle miRNA Profiles Distinguish Chronic Obstructive Pulmonary Disease Exacerbations and Disease Severity

Purpose

Molecular biomarkers for chronic obstructive pulmonary disease (COPD) severity have been difficult to identify. We aimed to assess extracellular vesicle miRNAs’ potential as a blood biomarker in discriminating disease severity in participants with COPD.

Patients and Methods

Plasma extracellular vesicles (EVs) were obtained from two COPD cohorts (n = 20 during an exacerbation event, n = 20 during stable state), with varying disease severity (GOLD stages). The miRCURY LNA miRNA Serum/Plasma assay, specific to 179 targets, was used to evaluate EV miRNA expression. The miRNAs that were significantly dysregulated were further assessed for discriminatory power using ROC curve analysis, as well as their role in relevant biological pathways.

Results

One miRNA was significantly dysregulated between moderate GOLD participants compared to severe/very severe GOLD participants, with an AUC of 0.798, p = 0.01 for miR-374b-5p. Five miRNAs were significantly dysregulated between exacerbating and stable COPD participants, with miR-223-3p resulting in the highest AUC (0.755, p = 0.006) for a single miRNA, with a combination of three miRNAs (miR-92b-3p, miR-374a-5p and miR-106b-3p) providing the highest discriminatory power (AUC 0.820, p = 0.001). The “cytokine–cytokine receptor interaction” (hsa04060 pathway) was the most significant KEGG pathway enriched for three out of the five miRNAs associated with COPD exacerbations.

Conclusion

This initial small-scale study suggests that the bioactive cargo (miRNAs) in plasma EVs holds specific biological information for the severity of airflow obstruction and COPD exacerbations, warranting further investigation.

Burden of Care for Children with Bronchiectasis from Parents/Carers Perspective

Bronchiectasis is a neglected chronic respiratory condition. In children optimal appropriate management can halt the disease process, and in some cases reverse the radiological abnormality. This requires many facets, including parental/carer bronchiectasis-specific knowledge, for which there is currently no such published data. Further, the importance of patient voices in guiding clinical research is becoming increasingly appreciated. To address these issues, we aimed to describe the voices of parents of children with bronchiectasis relating to (a) burden of illness and quality of life (QoL), (b) their major worries/concerns and (c) understanding/management of exacerbations. The parents of 152 children with bronchiectasis (median age = 5.8 years, range 3.5-8.4) recruited from the Queensland Children's Hospital (Australia) completed questionnaires, including a parent-proxy cough-specific QoL. We found that parents of children with bronchiectasis had impaired QoL (median 4.38, range 3.13-5.63) and a high disease burden with median 7.0 (range 4.0-10.0) doctor visits in 12-months. Parental knowledge varied with only 41% understanding appropriate management of an exacerbation. The highest worry/concern expressed were long-term effects (n = 42, 29.8%) and perceived declining health (n = 36, 25.5%). Our study has highlighted the need for improved education, high parental burden and areas of concern/worry which may inform development of a bronchiectasis-specific paediatric QoL tool.