Spanish multicentre study on morbidity and pathogenicity of tracheal bronchus in children.

Tracheal bronchus (TRB) has been generally considered an anatomical variant of the tracheobronchial tree without a precise pathological effect. Its prevalence is estimated to be between 0.2% to 3% of all children undergoing bronchoscopy and scientific information has been limited to case reports or small case series. Our working hypothesis was that TRB could trigger by itself recurrent or persistent respiratory symptoms. The objective of this retrospective and multicentre study of children with a diagnosis of TRB, coming from the main paediatric pulmonology units of Spain, was to determine the anatomical and clinical characteristics, including comorbidities, of TRB in childhood and their impact in the patients' clinical outcomes. One hundred thirty-three patients from 13 institutions were included in the study. Mean diagnostic age was 3.4 years and flexible bronchoscopy was the initial diagnostic method in 85% of cases. All TRB were located on the right wall of the trachea: 76% in the lower third and 24% in the carina. The most common clinical manifestations were obstructive bronchitis (53.3%) and recurrent pneumonia (46.6%), usually affecting the right upper lobe. Regarding associated anomalies, 33% had tracheomalacia, 32% congenital cardiovascular malformations, 28% gastroesophageal reflux, 22.5% congenital tracheal stenosis, and 8.3% Down syndrome. This series appears to be the most extensive published to date addressing this topic and, according to our data, TRB does not appear to be a mere incidental finding but is more likely linked to a wide range of congenital anomalies and contributes by itself to the recurrent respiratory symptomatology that these children exhibit.

Oxidative stress and inflamatory plasma biomarkers in respiratory syncytial virus bronchiolitis.

INTRODUCTION: Oxidative stress (OS) plays a crucial role in the pathogenesis of inflammatory lung diseases. OBJECTIVES: (i) We determined whether acute bronchiolitis (AB) caused by respiratory syncytial virus (RSV) induced OS; (ii) assessed whether OS biomarkers correlated with the severity of RSV-AB; and (iii) studied whether the levels of interleukins are associated with OS biomarkers. METHODS: We performed an observational study by comparing healthy infants (Group 1) with RSV-AB infants, classified as Group 2 (pulse oximetry (SpO2 ) >93%), and Group 3 (SpO2 ≤ 92%), which needed oxygen therapy. Blood samples were collected to determine the levels of lipid peroxidation (LPO) products (LPO), total glutathione (TG), oxidised glutathione (GSSG), reduced glutathione (GSH), glutathione peroxidase (GPx), interleukins (ILs) IL-10, IL-6, IL-8, interferon-gamma (IFNγ), tumour necrosis factor-alpha (TNFα) and macrophage inflammatory proteins (MIP α and MIP ß). RESULTS: Forty-six RSV-AB infants (47% needed oxygen therapy) and 27 healthy infants were included. The GSH/GSSG ratio was lower in RSV-AB infants than in Group 1 (P<0.001). GSSG and GPx were significantly higher in Group 3. GSSG predicted the need for oxygen therapy with an optimal cut-off point of 15 µM/g for haemoglobin. The GSH/GSSG ratio negatively correlated with IL-6 (P: 0.014), IL-8 (P: 0.014) and IL-10 (P: 0.033). Group 3 exhibited a direct correlation between GPx and IL-10 levels (P: 0.024) and between LPO and MIP ß (P: 0.003). CONCLUSIONS: RSV induced OS in AB. An increase in GSSG correlated with the disease severity in the infants. OS may contribute to the pathogenesis of RSV-AB.