Chronic Cough Postacute Respiratory Illness in Children: A Cohort Study

Abstract

To determine the prevalence of chronic cough after acute respiratory illness and evaluate the diagnostic outcomes of children with chronic cough lasting >28 days after emergency department (ED) presentation.Children <15 years of age who presented to an ED for acute respiratory illness with cough were recruited into the study.This was a prospective cohort study. From December 2011 to August 2014, children who presented to an Australian Children’s Hospital ED for acute respiratory illness with symptom of cough were managed for 28 days to ascertain their cough status. If the chronic cough persisted at day 28, children were evaluated by a pediatric pulmonologist 4–6 weeks after their initial ED presentation. Evaluation by the pediatric pulmonologist included nasal swab and additional tests (bronchoscopy, chest computed tomography) as deemed necessary.In total, 2856 children were screened, and 876 children were enrolled into the study. The median age was 2.3 years (0.5 months to 14.7 years) and 60% were boys. Cough persistence at day 7 was 64.7%, 39.0% at day 14, 25.9% at day 21, and 20.3% at day 28. In total, 171 children had cough persisting >28 days; 2 children had positive pertussis test results, and 1 child had positive results for Mycoplasma pneumoniae on the basis of the initial nasal swab collection; 117 of 171 children were evaluated by the pulmonologist. Fifty-five (47.1%) children were diagnosed with protracted bacterial bronchitis by the pulmonologist. A new and serious chronic lung disease was diagnosed in 36 of 117 (30.8%) of these children, which included asthma, aspiration disorder, obstructive sleep apnea, tracheobronchomalacia, and bronchiectasis. Approximately one-third of these children were given >1 diagnosis.Acute cough typically resolves within 1–3 weeks after acute respiratory illness. When it persists >4 weeks, further evaluation is warranted. Parents should be educated that chronic cough should not be ignored because it is often a harbinger for an underlying respiratory condition.As a clinician, it is sometimes hard to determine if that cough is “bad luck” from getting colds back to back or if it really does represent an underlying respiratory pathology. The authors of this article remind us that we need to delve further when children have a history of prolonged cough lasting >4 weeks or have recurrent cough.