Ischemic pancreatitis with infected walled-off necrosis with a colonic fistula after cardiopulmonary bypass successfully treated by endoscopic ultrasound-guided drainage

A 72-year-old man who had been on continuous ambulatory peritoneal dialysis treatment for 10 years underwent cardiopulmonary bypass for aortic valve replacement due to aortic valve stenosis. After surgery, he experienced pancreatitis, and rupture of a splenic artery aneurysm. He went into cardiopulmonary arrest but was successfully treated by transcatheter arterial embolization (TAE) with cardiopulmonary resuscitation. At three weeks after TAE, CT showed heterogeneous enhancement and the accumulation of pancreatic fluid in the pancreatic tail. At 4 months after TAE, he had sepsis and CT showed greater fluid collection with emphysema in comparison to 3 months previously. We diagnosed infected walled-off necrosis (WON). Conservative therapy with antibiotics was not sufficiently effective; thus, we performed endoscopic ultrasound-guided drainage (EUS-D). Contrast imaging revealed WON with colonic fistula. The WON remarkably decreased in size on CT after EUS-D. We experienced a rare case of ischemic acute pancreatitis (AP) caused by cardiopulmonary bypass complicated with infected WON with a colonic fistula. Ischemic AP more frequently shows a severe course with a fatal outcome in comparison to AP of other causes. However, in our case, ischemic AP with infected WON was successfully treated by EUS-D despite the presence of a WON with a colonic fistula.