Post-Pancreatectomy Acute Pancreatitis—The New Criteria Fail to Recognize Significant Presentations

Abstract

Background Post-pancreatectomy acute pancreatitis (PPAP) is a newly described clinical entity defined as elevated serum amylase sustained ≥ 48 h postoperatively, radiological findings consistent with acute pancreatitis, and associated clinically relevant features. This study aimed to investigate the incidence of PPAP and the rate of major complications after pancreatoduodenectomy (PD) in patients with only transiently elevated serum amylase. Methods A retrospective single-center observational study was conducted including consecutive patients ≥ 18 years of age undergoing PD at Karolinska University Hospital, between 2008 and 2020. Serum amylase on postoperative day (POD) 1 and 2 and records from computer tomography were analyzed and correlated with postoperative major complications by logistic regressions. Results Of some 1078 patients that underwent PD, 284 exhibited sustained elevated serum amylase (according to PPAP criteria) and 183 transiently elevated serum amylase on either POD1 or POD2. Of the patients with sustained elevated levels, 43% (n = 123) developed major complications, but only 6.3% (n = 18) showed findings consistent with acute pancreatitis on imaging. Of the 183 cases that exhibited only transiently elevated serum amylase on either POD1 or POD2, 32% (n = 58) developed major complications. Conclusion Sustained hyperamylasemia was observed in 26% of patients after PD, and an additional 17% of patients had a transient elevation of serum amylase postoperatively. Acute pancreatitis after PD may be underdiagnosed, partly by overlooking transiently elevated serum amylase and partly by requiring imaging that potentially fails to recognize mild but complication-prone acute pancreatitis.

Association of Postoperative Hyperamylasemia With Clinically Relevant Postoperative Pancreatic Fistula in Pancreatoduodenectomy

“…Interestingly, only 18 (6.3%) patients in the sustained hyperamylasemia group showed radiological evidence of acute pancreatitis. The authors concluded that the current ISGPS criteria may underdiagnose PPAP by ignoring transient hyperamylasemia and excluding patients with no radiological evidence of acute pancreatitis [14].…”

“…However, a recently published retrospective study from Karolinska Institute in Sweden of 1,078 patients who underwent Whipple's PD found that the ISGPS criteria may underdiagnose post-pancreatectomy acute pancreatitis because it ignores transiently elevated serum amylase on POD1 and 2 and only considers sustained hyperamylasemia for more than 48 hours postoperatively as significant. Additionally, it requires imaging which is not routinely done in all patients postoperatively and might miss early changes of acute pancreatitis [14].…”

Effects of Pancreatic Surgery : Quality of Life, Cost-effectiveness and Postoperative Results

“…The authors argued that the definition of PPAP relies too heavily on radiological findings as mild pancreatitis can be clinically impactful but difficult to identify on imaging. 94 Table 3. Classifications of postoperative complications after pancreatic surgery according to the International Study Group of Pancreatic Surgery and the International Study Group of Liver Surgery.…”

Pancreatectomy and Pancreatic Surgery

“…PPAP can trigger further postoperative complications. The diagnosis is based on biochemical, radiological, and clinical criteria, and involves postoperative serum hyperamylasemia (POH) higher than the institutional upper limit for normal, sustained elevated for at least the first 48 h following surgery, as well as radiologic alterations consistent with PPAP, and associated clinically relevant signs [39].…”