Do combined upper airway cultures identify lower airway infections in children with chronic cough?

Abstract

Background Obtaining lower airway specimens is important for guiding therapy in chronic lung infection but is difficult in young children unable to expectorate. While culture‐based studies have assessed the diagnostic accuracy of nasopharyngeal or oropharyngeal specimens for identifying lower airway infection, none have used both together. We compared respiratory bacterial pathogens cultured from nasopharyngeal and oropharyngeal swabs with bronchoalveolar lavage (BAL) cultures as the “gold standard” to better inform the diagnosis of lower airway infection in children with chronic wet cough. Methods Nasopharyngeal and oropharyngeal swabs and BAL fluid specimens were collected concurrently from consecutive children undergoing flexible bronchoscopy for chronic cough and cultured for bacterial pathogens. Results In cultures from 309 children (median age, 2.3 years) with chronic endobronchial suppuration, all main pathogens detected (Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis) were more prevalent in nasopharyngeal than oropharyngeal swabs (37%, 34%, and 23% vs 21%, 6.2%, and 3.2%, respectively). Positive and negative predictive values for lower airway infection by any of these three pathogens were 63% (95% confidence interval [95% CI] 55, 70) and 85% (95% CI, 78, 91) for nasopharyngeal swabs, 65% (95% CI, 54, 75), and 66% (95% CI, 59, 72) for oropharyngeal swabs, and 61% (95% CI, 54,68), and 88% (95% CI, 81, 93) for both swabs, respectively. Conclusions Neither nasopharyngeal nor oropharyngeal swabs, alone or in combination, reliably predicted lower airway infection in children with chronic wet cough. Although upper airway specimens may be useful for bacterial carriage studies and monitoring antimicrobial resistance, their clinical utility in pediatric chronic lung disorders of endobronchial suppuration is limited.

Predictors of time to cough resolution in children with chronic wet cough treated with antibiotics after bronchoscopy

“…Data including patients’ demographics, duration of prior cough at bronchoscopy, household tobacco smoke exposure, diagnoses, past pneumonia history, complete blood count, airway (ie, BAL) cellularity, lower airway bacterial culture, and respiratory virus detection were extracted from the database. A positive culture in the BAL was defined as the growth of >10 4 CFU/mL of a single bacteria species . Positive culture of the three most common bacteria Haemophilus influenzae , Moraxella catarrhalis , and Streptococcus pneumonia were included as these are found in children with chronic wet cough …”

“…A positive culture in the BAL was defined as the growth of >10 4 CFU/mL of a single bacteria species . Positive culture of the three most common bacteria Haemophilus influenzae , Moraxella catarrhalis , and Streptococcus pneumonia were included as these are found in children with chronic wet cough …”

Chronic cough in childhood: A systematic review for practical guidance by the Italian Society of Pediatric Allergy and Immunology

“…19 Although spirometry (pre-and post-ß2-agonists) is commonly performed in daily practice, literature data are lacking regarding its use in the pediatric population with chronic cough. [9][10][11][12][14][15][16][17][18][19][20][21][22][23] Nevertheless, in their multicenter study, the authors revealed that spirometry showed a sensitivity of 0.03 (95% CI: 0.01-0.06), specificity of 1.0 (95% CI: 0.89-1.00), positive PV of 1.00 (95% CI: 0.60-1.0), negative PV of 0.13 (95% CI: 0.09-0.17), positive LR infinity, and negative LR of 0.97 (95% CI: 0.95-0.95) for the specific cough all-causes. 13 Finally, only one of the studies included in our systematic review investigated the diagnostic role of fractional…”

“…18 Only one study did not make the chronic cough definition explicit. 17 More recently, according to the latest CHEST Expert Cough Panel guidelines, chronic cough has been defined as the presence of daily cough for more than 4 weeks for children aged ≤14 years. 26…”

“…Although none of the included studies was explicitly focused on clinical history and presentation of chronic cough in children, [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] it has been noted that positive personal and family history of atopy and a previous history of chronic cough were commonly detected in children affected by chronic cough. 11,16,[18][19][20] Passive tobacco exposure was commonly reported in patients with chronic cough.…”