1.1 Case presentation
A 7-month-old girl was admitted to respiratory department with persistent wet cough and recurrent wheezing. She was diagnosed with recurrent pneumonia and treated with antibiotics, bronchodilators and glucocorticoids empirically when symptoms worsen. She was full-term with normal manifestation during perinatal period. She occasionally expectorated bright-yellow sputum when drinking breast or milk. Chest computed tomography (CT) images showed an abnormal bronchial bifurcation originated from the right main bronchus (Figure 1A). Both transverse (Figure 1B) and anamorphic (Figure 1C) chest CT indicated gas shadow anterior to the esophagus at the diaphragm level. Yellow, serous secretions emerging from an anomalous orifice located at the right main bronchus via bronchoscopy (Figure 2A and 2B). The bright-yellow BALF was obtained and tested for bilirubin with positive detection. The contrast agent meglumine was injected through the anomalous orifice via flexible bronchoscope. Chest CT examination showed the contrast agent entered the abnormal bronchus and traveled downward, passing through the left hepatic duct, the common hepatic duct and common bile duct (Figure 3). The girl was diagnosed with congenital bronchobiliary fistula (CBBF) based on these findings. She had operation to remove the anomalous fistula. During the ten months following-up, the girl was absent from wet cough, wheezing and pneumonia. Chest computed tomography examination demonstrated that the anomalous orifice and lung shadow disappeared (Figure 1D). Bronchoscopy showed an anomalous diverticulum (Figure 2C) and the BALF was colorless with no bilirubin presented.
Pathological examination showed tubular structure of cartilage and muscle, lined with stratified squamous epithelium, pseudostratified columnar ciliated epithelium and submucosal glands (Figure 4).