Is secondary tracheomalacia associated with airway inflammation and infection

BACKGROUND In secondary tracheomalacia due to mediastinal vascular anomalies (MVA) one of the most prevalent symptom are recurrent lower respiratory tract (LRT) infections. Whether this condition could result in persistent LRT inflammation and subclinical infection is not known. METHODS A retrospective study was performed on records of children with tracheomalacia due to MVA and recurrent respiratory infections who underwent computed tomography (CT) scan, bronchoscopy and bronchoalveolar lavage (BAL) as part of their clinical evaluation. RESULTS 31 children were included in the study: 21 with aberrant innominate artery (AIA), 4 with right aortic arch (RAA) and 1 with double aortic arch (DAA) and 5 with AIA associated with RAA. BAL fluid cytological evaluation showed increased neutrophil percentages and normal lymphocyte and eosinophil proportions. Microorganism growth was detected in 13 of BAL samples, with a bacterial load ≥104 colony-forming-units (CFU)/mL in 8 (25.8%) of them. Most isolates were positive for H. influenzae. Bronchiectasis was detected in 4 children, all with BAL culture positive for H. influenzae. 4 patients underwent MVA surgical correction and 27 conservative management, i.e., respiratory physiotherapy in all and high-dose amoxicillin/clavulanic acid (40 mg/kg/ day) for 2-4 weeks in those with significant bacterial growth excellent outcome in most of them. CONCLUSIONS Neutrophilic alveolitis is detectable in secondary tracheomalacia but is associated with a clinically significant bacterial load only in a quarter of the patients. Caution should be used in inappropriate antibiotic prescription to avoid the emergence of resistance, whilst airway clearance maneuvers and infection preventive measures should be promoted.