RT Journal Article SR Electronic T1 Malacia, inflammation and bacterial colonisation of the conducting airways in infants with persistent respiratory symptoms JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p4277 VO 38 IS Suppl 55 A1 Frans De Baets A1 Iris De Schutter A1 Claudia Aarts A1 Filomeen Haerynck A1 Sabine Van Daele A1 Elke De Wachter A1 Anne Malfroot A1 Petra Schelstraete YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p4277.abstract AB In infants with persistent respiratory symptoms, wet cough and wheezing despite regular anti-asthma inhalation treatment diagnostic investigations to exclude underlying disease are warranted.Prospectively 124 infants with treatment resistant respiratory symptoms were enrolled. Sweat test, 24 hours oesophageal pH measurement and fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL) were performed. BAL fluid was processed for neutrophil counting and bacterial culture. Inflammation of the respiratory mucosa was registered.A 24 hours oesophageal pH measurement was positive in 29%. A structural abnormality of the central airways was found in 47% (40% females). In 19% of infants no anatomical anomalies nor chronic inflammation of the respiratory mucosa were observed, whereas in 64% definite macroscopic mucosal inflammation was registered. Pronounced inflammation of the respiratory mucosa was associated with a significantly higher percentage of neutrophils in the BAL fluid, 48% (IQR 14 – 82) compared to 7% (IQR 0 – 16) (p< 0,025) in the normal group. A positive BAL culture was found in 62% of the infants with pronounced mucosal inflammation compared to 25% in the group without inflammation (p< 0.016). Fifty six percent of the BAL fluid samples was positive for bacterial culture.In infants with treatment resistant respiratory symptoms, nearly half have anatomical anomalies of the central airways. In 62% of the children with pronounced mucosal inflammation a positive BAL culture and a significantly higher percentage of BAL fluid neutrophils were detected, suggesting chronic bronchial infection as a possible reason for ongoing respiratory symptoms.