Postoperative pancreatic abscess due to Plesiomonas shigelloides. Plesiomonas shigelloides is being recognized with increasing frequency as a human pathogen. The organism is ubiquitous in fresh and brackish water, and clinical illness has been associated with foreign travel and ingestion of inadequately cooked seafood. We describe a 64-year-old Filipino woman who presented 2 weeks after elective cholecystectomy and pancreatic biopsy with left upper quadrant pain, abdominal distention, and fever. Computerized tomography of the abdomen revealed an abscess in the tail of the pancreas with fluid accumulation in the lesser omental sac. Percutaneous aspiration yielded purulent material, and P. shigelloides was recovered in pure culture. To our knowledge, this is the first reported case of pancreatic abscess due to P. shigelloides. 