We read with great interest the recent article by Wurzel et al, published in CHEST (November 2016), on the natural history and risks for bronchiectasis in children with protracted bacterial bronchitis (PBB). In evaluating the 2-year outcomes of 161 of these children, it was found that a great proportion (43.5%) had more than three episodes of bacterial bronchitis per year, and 13 patients (8.1%) were diagnosed with bronchiectasis. Haemophilus influenzae infection was demonstrated by BAL in 85% and 49% of children with or without bronchiectasis, respectively, and further characterized in 82% of the samples as a nontypeable form. In multivariate analysis, recurrent episodes of PBB and the presence of high H influenzae titers in BAL fluid were major risk factors for bronchiectasis at 2 years, suggesting a possible role of this specific infection in the pathogenesis of bronchiectasis. This finding is in accordance with the recognition of H influenzae as a major bacterial pathogen associated with chronic respiratory disorders through its ability to form biofilms., PBB was classically defined not only as a history of chronic wet cough but also as evidence of response to 2-week treatment with amoxicillin clavulanate., There is evidence that exposure to subinhibitory concentrations of beta-lactam antibiotic may act as a signaling molecule that promotes transformation of nontypeable H influenzae into the biofilm phenotype favoring antibiotic resistance and increased susceptibility to reinfection after treatment. In addition, in children with chronic suppurative lung disorders, increased local airway inflammation is associated with a poorer systemic cell-mediated immune response, leading to reduced capacity to produce interferon-γ in response to nontypeable H influenzae. Thus, adherence to antibiotic treatment should be monitored in these children to avoid subinhibitory concentrations that may favor PBB recurrence. The opportunity to switch from twice daily to thrice daily administration or to increase the dosage should be considered in specific cases to lengthen the time at higher minimum inhibitory concentration levels.