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

Cough in Protracted Bacterial Bronchitis and Bronchiectasis

Chronic cough in children is a common condition for which patients seek medical attention, and there are many etiologies. Of the various causes of chronic cough in children, protracted bacterial bronchitis (PBB) is one of the commonest causes, and bronchiectasis is one of the most serious. Together, they lie on different ends of the spectrum of chronic wet cough in children. Cough is often the only symptom present in children with PBB and bronchiectasis. This review highlights the role of cough as a marker for the presence of these conditions, as well as an outcome endpoint for treatment and research.

Phenotypic Features of Pediatric Bronchiectasis Exacerbations Associated With Symptom Resolution After 14 Days of Oral Antibiotic Treatment

BACKGROUND

Respiratory exacerbations in children and adolescents with bronchiectasis are treated with antibiotics. However, antibiotics can have variable interindividual effects when treating exacerbations.

RESEARCH QUESTION

Can phenotypic features associated with symptom resolution after a 14-day course of oral antibiotics for a nonsevere exacerbation of bronchiectasis be identified?

STUDY DESIGN AND METHODS

Combining data from two multicenter randomized controlled trials, we identified 217 children with bronchiectasis assigned to at least 14 days of oral antibiotics to treat nonsevere (nonhospitalized) exacerbations. Univariable and then multivariable logistic regression were used to identify factors associated with symptom resolution within 14 days of commencing antibiotics. Identified associations were re-evaluated by mediation analysis.

RESULTS

Of the 217 study participants (52% male patients), 41% were Indigenous (Australian First Nations, New Zealand Māori, or Pacific Islander). The median age was 6.6 years (interquartile range, 4.0-10.1 years). By day 14, symptoms had resolved in 130 children (responders), but persisted in the remaining 87 children (nonresponders). Multivariable analysis found those who were Indigenous (adjusted OR [AOR], 3.59; 95% CI, 1.35-9.54) or showed new abnormal auscultatory findings (AOR, 3.85; 95% CI, 1.56-9.52) were more likely to be responders, whereas those with multiple bronchiectatic lobes at diagnosis (AOR, 0.66; 95% CI, 0.46-0.95) or higher cough scores when starting exacerbation treatment (AOR, 0.55; 95% CI, 0.34-0.90) were more likely to be nonresponders. Detecting a respiratory virus at the beginning of an exacerbation was not associated with antibiotic failure at 14 days.

INTERPRETATION

Children with Indigenous ethnicity, milder bronchiectasis, mild exacerbations (low reported cough scores), or new abnormal auscultatory signs are more likely to respond to appropriate oral antibiotics than those without these features. These patient and exacerbation phenotypes may assist clinical management and development of biomarkers to identify those whose symptoms are more likely to resolve after 14 days of oral antibiotics.

TRIAL REGISTRY

Australian New Zealand Clinical Trials Registry; Nos.: ACTRN12612000011886 and ACTRN12612000010897; URL: https://www.anzctr.org.au.

Pediatric flexible bronchoscopy: A single-center report

INTRODUCTION

Pediatric flexible laryngotracheal bronchoscopy (FB) is an integral part of diagnostics and treatment at tertiary pediatric respiratory centers.

AIM

FBs performed between 2013 and 2018 at our Pediatric Allergy and Respiratory Medicine Unit of the Department of Women's and Children's Health at Padua University were examined in terms of the indications, findings, and adverse events.

MATERIALS AND METHODS

The electronic medical records of pediatric patients who underwent FB at least once between 1 January 2013 and 31 December 2018 were considered. Patients' clinical data, indications for FB, anatomical findings, information derived from bronchoalveolar lavage (BAL) and bronchial brushing, and possible adverse events were analyzed.

RESULTS

There were 447 pediatric FBs performed in 428 patients (aged from 1 month to 18 years) for diagnostic purposes (92.4%), to clear secretions (3.6%), or to monitor a known condition (4.0%). The main indications were recurrent lower respiratory tract infections (LRTI, 32.2%) and chronic wet cough (9.4%). Lower airway malacia was the most common abnormal finding in these two groups (36.1% and 28.6%, respectively). BAL bacterial culture was positive in 55 children (39.6%) with recurrent LRTI and in 25 (59.5%) with chronic wet cough, being Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis the microorganisms most commonly isolated. FB proved a safe procedure and was well tolerated.

CONCLUSIONS

Pediatric FB is an essential tool at our tertiary pediatric respiratory center. It helps establish the anatomical conditions underlying several chronic respiratory conditions and any correlated microbiological findings, with a significant impact on further patient management.

Duration of amoxicillin-clavulanate for protracted bacterial bronchitis in children (DACS): a multi-centre, double blind, randomised controlled trial

BACKGROUND

Protracted bacterial bronchitis (PBB) is a leading cause of chronic wet cough in children. The current standard treatment in European and American guidelines is 2 weeks of antibiotics, but the optimal duration of therapy is unknown. We describe the first randomised controlled trial to assess the duration of antibiotic treatment in children with chronic wet cough and suspected PBB. We hypothesise that 4 weeks of amoxicillin-clavulanate is superior to 2 weeks for improving clinical outcomes.

METHODS

Our parallel, double-blind, placebo-controlled, randomised controlled trial was completed in four Australian hospitals. Children aged 2 months to 19 years with chronic (>4 weeks duration) wet cough, and suspected PBB were randomly assigned (1:1) using permuted block randomisation (stratified by age and site) to 4 weeks of amoxicillin-clavulanate (25-35 mg/kg twice daily oral suspension; 4-week group) or 2 weeks of amoxicillin-clavulanate followed by 2 weeks of placebo (2-week group). The children, caregivers, all the study coordinators, and investigators were masked to treatment assignment until data analysis was completed. The primary outcome was clinical cure (cough resolution) by day 28. Secondary outcomes were recurrence of PBB at 6 months, time to next exacerbation, change in Parent-proxy Cough-Specific Quality-of-Life (PC-QoL) score from baseline to day 28 and from day 28 to 7 months, adverse events, nasal swab bacteriology, and antimicrobial resistance. Analyses followed the intention-to-treat principle. This trial is complete and registered with Australian/New Zealand Registry, ACTRN12616001725459.

FINDINGS

Between March 8, 2017, and Sept 30, 2019, 106 children were randomly assigned (52 in the 4-week group, median age 2·2 years [IQR 1·3-4·1]; 54 in the 2-week group, median age 1·7 years [1·2-3·8]) with 90 children completing the 4-week treatment. By day 28, the primary endpoint of clinical cure in the 4-week group (32 [62%] of 52 patients) was not significantly different to the 2-week group (38 [70%] of 54 patients; adjusted relative risk 0·87 [95% CI 0·60 to 1·28]; p=0·49). Time to next wet cough exacerbation was significantly longer in the 4-week group than the 2-week group (median 150 days [IQR 38-181] vs 36 days [15-181]; adjusted hazard ratio 0·47 [0·25 to 0·90]; p=0·02). The rate of recurrence of PBB at 6 months was 17 (53%) of 32 patients in the 4-week group vs 28 (74%) of 38 patients in the 2-week group, but the difference between the groups was not significant (adjusted odds ratio 0·39 [0·14 to 1·04]; p=0·07). PC-QoL significantly improved from baseline to day 28 in both groups, but there was no significant difference between them (mean difference in change -0·2 [95% CI -1·0 to 0·6]; p=0·64). From day 28 to 7 months, median PC-QoL remained stable in both groups with no difference in change between them. Data on respiratory pathogens and antimicrobial resistance (paired swabs available for 48 children) were similar between groups. Adverse events occurred in 13 (25%) children in the 2-week group and ten (19%) in the 4-week group (p=0·57).

INTERPRETATION

A 4-week course of amoxicillin-clavulanate for treating children with chronic wet cough and suspected PBB confers little advantage compared with a 2-week course in achieving clinical cure by 28 days. However, as a 4-week duration led to a longer cough-free period, identifying children who would benefit from a longer antibiotic course is a priority.

FUNDING

Queensland Children's Hospital Foundation.