To investigate the application value of nephroscopic treatment for the infection after internal drainage in severe acute pancreatitis patients complicated with walled-off necrosis (WON).

Clinical data of 5 WON patients who were misdiagnosed with pancreatic pseudocyst and developed infected pancreatic necrosis after undergoing internal drainage in Chinese PLA General Hospital between January 2010 and February 2016 were retrospectively analyzed. Among the 5 patients, 3 were males and 2 were females, with the age ranging from 39 to 67 years old and the median of 47 years old. Two cases underwent open internal drainage and 3 underwent gastroscopic percutaneous catheter internal drainage. Typical clinical and imaging manifestations of infected pancreatic necrosis were all observed postoperatively. The informed consents of all patients were obtained and the local ethical committee approval was receive. Patients initially underwent CT guided percutaneous catheter drainage (PCD), and then underwent percutaneous nephroscopic debridement of peripancreatic necrotic tissues by retroperitoneal approach and postoperative lavage and drainage.

Four cases recovered and discharged from hospital after once nephroscopic treatment, and 1 after twice nephroscopic treatment. The median postoperative length of stay was 15(7-32) d. No perioperative death or postoperative complications were observed.

Nephroscopic treatment is a good remedial therapy with advantages of minimal invasion and good efficacy for infection after internal drainage in patients with WON who are misdiagnosed with pancreatic pseudocyst.

Necrosis; Pancreatic pseudocysts; Internal drainage; Nephroscopic necrosectomy