Diagnostic imaging of a large pancreatic pseudocyst with infection over time in a dog

A 5-year-old Pompitz presented with anorexia and vomiting. Radiographs showed a half-moon-shaped mass in the left cranial abdomen. A large cyst was identified near the left pancreas on ultrasound. Computed tomography revealed a fluid-attenuating mass with rim enhancement in the pancreas. Laboratory tests identified Staphylococcus warneri in the cystic lesion, and pancreatic pseudocyst with infection was suspected. The fluid accumulation and clinical signs recurred over several months. Pre-operative magnetic resonance imaging showed a hyperintense cystic lesion with a duct-like structure and hyperintense line between the cyst and the gastric wall on T2-weighted images as well as signal change of the lesion on diffusion-weighted imaging. A partial pancreatectomy was performed, and a pancreatic pseudocyst was confirmed on histopathology. This is a rare case of a large pancreatic pseudocyst from infection with imaging findings in a dog.