Esophagobronchial fistulae: Diagnosis by MDCT with oral contrast swallow examination of a benign and a malignant cause
A 15-year-old male presented with cough, mucopurulent expectoration, and dyspnea since 3 months. There was history of exacerbation of cough after swallowing. This finding of swallow–cough sequence has been referred to as Ono's sign.[] A chest radiograph revealed complete opacification of the right hemithorax with volume loss suggesting complete collapse of the right lung with mediastinal shift to the right []. A plain and intravenous contrast-enhanced CT study with oral contrast swallow was performed on a 128-slice MDCT scanner (Siemens Somatom Definition AS, Erlangen, Germany). The study revealed complete collapse of the right lung with irregular dilated ectatic bronchi in the right lower lobe []. There was stenosis and diffuse narrowing of the right mainstem bronchus with nodularity of the mucosa seen best on the virtual bronchoscopy []. The right main pulomanary artery (MPA) was narrow in caliber. There was a resultant significant shift of the mediastinum and heart to the right. An air-filled tract was noted extending from one of the right lower lobar bronchi toward the posterior mediastinum with ill-defined soft tissue around it. The possibility of an esophagobronchial fistula was suspected, and we did a CT oral contrast swallow study to detect it. Oral contrast swallow study performed with the patient in right decubitus position using diluted non-ionic iodinated contrast medium (1:20 dilution of iohexol with normal saline). It depicted the site and the fistula tract between the right lateral wall of the esophagus and one of the ectactic bronchi in the right lower lobe of the lung. Thick MIP images and VRT processing demonstrated the fistula site and tract [Figures and ]. Right adrenal gland calcification was also noted. These imaging findings led us to conclude that these changes were most likely the sequelae of chronic tuberculosis. The patient underwent an open right pneumonectomy with repair of the fistula. Histology of the lung specimen revealed distorted bronchioles with diffuse and focal dense infiltration by mononuclear cells and giant cells. Lymph nodes with prominent germinal centers were also seen.