Protracted bacterial bronchitis: The last decade and the road ahead

Protracted Bacterial Bronchitis in Children: Natural History and Risk Factors for Bronchiectasis

BACKGROUND

Protracted bacterial bronchitis (PBB) and bronchiectasis are distinct diagnostic entities that share common clinical and laboratory features. It is postulated, but remains unproved, that PBB precedes a diagnosis of bronchiectasis in a subgroup of children. In a cohort of children with PBB, our objectives were to (1) determine the medium-term risk of bronchiectasis and (2) identify risk factors for bronchiectasis and recurrent episodes of PBB.

METHODS

One hundred sixty-one children with PBB and 25 control subjects were prospectively recruited to this cohort study. A subset of 106 children was followed for 2 years. Flexible bronchoscopy, BAL, and basic immune function tests were performed. Chest CT was undertaken if clinical features were suggestive of bronchiectasis.

RESULTS

Of 161 children with PBB (66% boys), 13 were diagnosed with bronchiectasis over the study period (8.1%). Almost one-half with PBB (43.5%) had recurrent episodes (> 3/y). Major risk factors for bronchiectasis included lower airway infection with Haemophilus influenzae (recovered in BAL fluid) (P = .013) and recurrent episodes of PBB (P = .003). H influenzae infection conferred a more than seven times higher risk of bronchiectasis (hazard ratio, 7.55; 95% CI, 1.66-34.28; P = .009) compared with no H influenzae infection. The majority of isolates (82%) were nontypeable H influenzae. No risk factors for recurrent PBB were identified.

CONCLUSIONS

PBB is associated with a future diagnosis of bronchiectasis in a subgroup of children. Lower airway infection with H influenzae and recurrent PBB are significant predictors. Clinicians should be cognizant of the relationship between PBB and bronchiectasis, and appropriate follow-up measures should be taken in those with risk factors.

Paediatric chronic suppurative lung disease: clinical characteristics and outcomes

We describe the clinical, bronchoscopic, bronchoalveolar lavage (BAL) and radiographic characteristics of children whose chronic wet cough did not resolve with oral antibiotics and which led to their hospitalisation for intravenous antibiotics and airway clearance therapy. Between 2010 and 2014, medical chart review identified 22 such children. Their median cough duration was 26 weeks (interquartile range (IQR) 13-52). All received oral antibiotics immediately before their hospitalisation (median 4 weeks; IQR 4-6.5). On chest examination, seven (31 %) children had auscultatory crackles. At bronchoscopy, 9 (41 %) had tracheomalacia, 18 (86 %) demonstrated airway neutrophilia (>15 %) and 12 (57 %) grew Haemophilus influenzae from their BAL fluid. They received intravenous antibiotics (mostly cefotaxime or ceftriaxone) and airway clearance therapy as inpatients (median 12.5 days (IQR 10.8-14). All were cough-free at follow-up.

CONCLUSION

The children's BAL characteristics are similar to those with protracted bacterial bronchitis and bronchiectasis, but their poor clinical response to oral antibiotics and non-specific chest CT findings differentiated them from these other two disorders. The findings are consistent with chronic suppurative lung disease. Intravenous antibiotics and airway clearance therapy should therefore be considered in children whose wet cough persists despite 4 weeks of oral antibiotics and where other causes of chronic wet cough are absent. What is known on this topic? • Chronic wet cough not resolving with appropriate antibiotics increases the likelihood of bronchiectasis. • Children with chronic suppurative lung disease (CSLD) have clinical features of bronchiectasis, but lack the radiographic evidence for this diagnosis.

WHAT THIS STUDY ADDS

• Children with CSLD have airway neutrophilia and predominantly Haemophilus influenzae in lower airway cultures, similar to children with protracted bacterial bronchitis and bronchiectasis. • Chronic wet cough in CSLD, unresponsive to oral antibiotics, resolves with intravenous antibiotics and airway clearance therapy.