Outcomes of Endoscopic Transgastric Necrosectomy for Infected and Sterile Walled-off Pancreatic Necrosis

Abstract

Introduction: Walled off pancreatic necrosis (WOPN), a severe complication of acute pancreatitis, can contain either infected or sterile contents. The incidence of infected necrosis (IN) is estimated to be 30.5%. A step-up approach to treatment, beginning with endoscopic transgastric necrosectomy (ETN) is now recommended. Little is known regarding differences in outcomes and procedural measures in patients undergoing ETN with infected versus sterile WOPN. We performed a retrospective review of patients undergoing ETN for WOPN comparing complication rates, number of required debridements, length of stay, need for additional surgical procedures, and demographic differences between those with IN versus those with sterile necrosis (SN). Methods: Charts of patients with WOPN undergoing ETN by two endoscopists at a single community hospital between August 2013 and September 2016 were reviewed. Patients less than 18 years of age were excluded. Either Fisher's exact test or Kruskal-Wallis test were used to assess statistical significance between the groups for the desired variables at a type I error of 0.05. Results: 19 patients were included. Twelve patients (63.1%) grew positive cultures from pancreatic aspirates. Patients with IN were younger (45 years vs. 57 years; p=0.03), and required more debridements (3.36 vs 1.71; p=0.048) compared to those with SN. Remaining comparisons trended towards, but did not reach statistical significance. Stents tended to remain in place longer in those with IN (37.8 vs 24.9 days; p=0.39). 83.3% of patients with IN experienced more than one complication compared with 42.7% of those with SN (p=0.13). Half of patients with IN required additional procedures compared to 14.3% of those with SN (p=0.17). No patients with SN required step-up to minimally invasive necrosectomy or percutaneous drain placement compared with one and three respectively in patients with IN. Patients with IN were hospitalized for a mean of 57.2 days, compared with 38.9 days for those with SN (p=0.12). Conclusion: Patients with IN were younger and required more debridements. This study was limited by small size. However, those with IN tended to require more procedures, longer lengths of stay, longer stent duration, and experienced more complications. Though causation cannot be inferred, patients with IN may benefit from a more aggressive treatment strategy. These findings also have prognostic implications relevant to setting appropriate patient expectations for this often prolonged illness.