Barium sulphate aspiration pneumonia in a cat with megaesophagus and dextroposition of the aortic arch: case report

ABSTRACT A six-month-old female cat suffered aspiration of an abundant amount of barium sulfate during a radiographic procedure for the diagnosis of megaesophagus. Latero-lateral contrast radiography revealed severe dilation of the thoracic esophagus cranial to the base of the heart. Persistence of the right aortic arch was suspected and later confirmed during corrective surgery. Accumulation of barium sulfate, used as a contrast agent, was clearly observed in the lumen of the bronchi, bronchioles, and alveoli in the radiographic image. Days after the surgery, the animal developed severe respiratory distress, which resulted in death. Cytology results and histology analysis using polarized light demonstrated that the lumen of bronchi, bronchioles, and alveoli exhibited evident histiocytic infiltration with cytoplasm filled by abundant amorphous refractive granular material consistent with barium sulfate. In this report, we describe the anatomical, cytological, histopathological (using polarized light), and x-ray findings of a case of barium sulfate aspiration pneumonia in a cat resulting from the use of this contrast medium for the diagnosis of megaesophagus secondary to persistent right aortic arch.