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

Abstract

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.

Tracheal anomalies associated with Down syndrome: A systematic review

“…A tracheal bronchus, also known as pig bronchus or “bronchus suis,” is defined as an anatomical variation in which an aberrant or additional bronchus originates from the supracarinal trachea. It is predominantly seen on the right side and has an estimated incidence of 0.06%–1.06% 46 . A tracheal bronchus is often asymptomatic and, therefore, reported prevalence rates in literature might underestimate the exact prevalence.…”

“…Interestingly, in a cohort study on children with respiratory complaints requiring flexible laryngotracheobronchoscopy, tracheal bronchus was seen in 21% of DS children compared with 2.1% in non‐DS controls 41 . Furthermore, a recent multicenter study on tracheal bronchus showed that 11/113 (8.3%) children with tracheal bronchus had DS 46 . As far as the affected side is described, all but one article on tracheal bronchus in DS concerned right‐sided tracheal bronchus.…”

Pediatric pulmonology 2019 year in review: rare and diffuse lung disease

“…14 Three 2019 papers addressed other abnormalities of airway branching -tracheal bronchus, bridging bronchus, and bronchogenic cyst. Moreno et al 15 reported on 133 pediatric patients with tracheal bronchus from 13 institutions across Spain. This anomaly occurs when the right upper lobe bronchus arises from the trachea, or less commonly, the carina.…”

What’s Wrong in the Airway?

“…Tracheal bronchus, in which the right upper lobe directly originates from the trachea, is not a rare condition. Its prevalence has recently been estimated to 0.2–3% of children undergoing bronchoscopy [2]. In most cases, it is found incidentally and is thus considered as a variant of the normal tracheobronchial anatomy [3].…”