The development of chronic cough in children following presentation to a tertiary paediatric emergency department with acute respiratory illness: study protocol for a prospective cohort study

Abstract

BackgroundAcute respiratory illness, a leading cause of cough in children, accounts for a substantial proportion of childhood morbidity and mortality worldwide. In some children acute cough progresses to chronic cough (>4 weeks duration), impacting on morbidity and decreasing quality of life. Despite the importance of chronic cough as a cause of substantial childhood morbidity and associated economic, family and social costs, data on the prevalence, predictors, aetiology and natural history of the symptom are scarce. This study aims to comprehensively describe the epidemiology, aetiology and outcomes of cough during and after acute respiratory illness in children presenting to a tertiary paediatric emergency department.Methods/designA prospective cohort study of children aged <15 years attending the Royal Children’s Hospital Emergency Department, Brisbane, for a respiratory illness that includes parent reported cough (wet or dry) as a symptom. The primary objective is to determine the prevalence and predictors of chronic cough (≥4 weeks duration) post presentation with acute respiratory illness. Demographic, epidemiological, risk factor, microbiological and clinical data are completed at enrolment. Subjects complete daily cough dairies and weekly follow-up contacts for 28(±3) days to ascertain cough persistence. Children who continue to cough for 28 days post enrolment are referred to a paediatric respiratory physician for review. Primary analysis will be the proportion of children with persistent cough at day 28(±3). Multivariate analyses will be performed to evaluate variables independently associated with chronic cough at day 28(±3).DiscussionOur protocol will be the first to comprehensively describe the natural history, epidemiology, aetiology and outcomes of cough during and after acute respiratory illness in children. The results will contribute to studies leading to the development of evidence-based clinical guidelines to improve the early detection and management of chronic cough in children during and after acute respiratory illness.

Prevalence, codetection and seasonal distribution of upper airway viruses and bacteria in children with acute respiratory illnesses with cough as a symptom

“…The use of anterior nasal rather than nasopharyngeal swabs may have led to an underestimation of bacteria species. However, anterior nasal swabs are less traumatic in young children and facilitate bilateral sampling; a loss in sensitivity for bacteria was considered acceptable for the purposes of the overall study [13] for which the samples were collected. The infrequency of detecting just a single bacterium with a virus precluded investigating the interactions between organisms in greater detail.…”

“…We conducted a prospective study of children aged <15 years presenting to the RCH ED with an ARI including cough as a symptom between 11 December 2011 and 30 August 2014. The primary objective of the overall cohort study was to determine the prevalence and predictors of chronic cough after ARI in children; its full study protocol has been published previously [13]. Here we focus on the microbiologic aspects of that primary study.…”

“…Bilateral anterior nasal swabs were obtained using the Virocult specimen collection system (Medical Wire and Equipment, Wiltshire, England, UK). Protocol-specific criteria with respect to the adequacy of collection technique helped assess sampling quality [13]. Swabs were stored at −80°C within 24 hours of collection and were transferred to the research laboratory for virus and bacteria identification by validated PCR assays, as described previously [14,15]…”

Chronic cough postacute respiratory illness in children: a cohort study

“…The full study protocol has been published 18. Children were followed for 28 days to ascertain cough status following enrolment.…”

“…At enrolment, a comprehensive questionnaire18 was completed using parental interview, consulting with the treating team and medical record review. Parents completed a cough diary (verbal category descriptive (VCD)19 score) for 28 days, supplemented by weekly contacts by study staff.…”