RESULTS
31 children, 15 males and 16 females, mean age at time of referral of 5.64+ 3.62 years, were included in the study. In all children fiberoptic bronchoscopy demonstrated the presence of pulsatile extrinsic compression of the trachea middle third, leading to different degree of narrowing that increased in expiration and, more, during coughing (figure 1). Mucus/mucopurulent secretions and various degree of congestion and edema of the airway mucosa were revealed. Chest CT scans demonstrated the presence of aberrant innominate artery (AIA) in 21 children, right aortic arch (RAA) in 4 children, double aortic arch (DAA) in 2 child and AIA associated with RAA in 5 children (figure 2). Analysis of BAL cells demonstrated a significant difference in total cell numbers, corrected per milliliter of BAL fluid recovered [92.03 (70.15-481.39) cells µL−1], compared to control values in our laboratory [132.15 (35.15-290.74) cells µL−1; p<0.01]. A neutrophilic alveolitis was detected, with 21.50 (10.55-66.10) neutrophil proportion, compared to control values of 1.70% (0.60–3.50) (p<0.01), but with normal lymphocyte and eosinophil counts (figure 3). Microbiological analysis of BAL fluid demonstrated bacterial growth in 35.5% of the children, but with a pathogen load> 105 colony-forming units (CFU)/mL only in 10,2% of them. In these cultures, 72.7% of the isolates wereHaemophilus influenzae , 27.3% Streptococcus pneumoniaeand, 9.0% each for Group A β-hemolytic streptococci (GABHS) andMoraxella catarrhalis (figure 4). Coinfection were present in two isolated, one being positive for Haemophilus influenzae plus SBEGA and the other for Haemophilus influenzae plus S. pneumoniae . BAL neutrophilia tended to be higher in children with bacterial load >103 CFU/mL (figure 5). Finally, chest CT scan demonstrated the presence of bronchiectasis in 13% of the children, 5.9+2.2 years old, of which one had a positive BAL culture (>104 CFU/mL) for