Postpancreatectomy acute pancreatitis after distal pancreatectomy: tri-institutional international cohort

BACKGROUND: The International Study Group for Pancreatic Surgery (ISGPS) recently introduced a standardized definition and grading system for postpancreatectomy acute pancreatitis (PPAP), which was validated for pancreatoduodenectomy but not for distal pancreatectomy (DP). This study investigated the incidence and predictors of PPAP following DP and its associated postoperative complications. METHODS: Patients who underwent DP for all indications between 2015 and 2022 at three European centres were retrospectively analysed. PPAP was defined according to the ISGPS criteria (postoperative serum hyperamylasaemia (POH), radiological findings) and patient clinical deterioration. Standard univariable and multivariable and receiver operating characteristic (ROC) curve analyses were conducted. RESULTS: Among 1192 patients, PPAP occurred in 45 (3.8%): 35 grade B (2.9%) and 10 grade C (0.8%). POH without PPAP occurred in 165 patients (13.8%). Clinical outcomes worsened progressively across patients without POH/PPAP, with POH only, and with PPAP (Clavien-Dindo ≥ IIIa: 17.8%, 21.2%, and 53.3%, respectively; overall P < 0.001). PPAP was associated with higher rates of postoperative complications, including pancreatic fistula (68.9%), delayed gastric emptying (17.8%), and unplanned intensive care unit admission (17.8%). Compared with POH only, PPAP was associated with higher C-reactive protein (CRP) levels on postoperative day (POD) 2 and POD3. Among patients with POH, higher CRP levels on POD3 remained independently associated with PPAP in multivariable analysis (adjusted odds ratio 1.01; P < 0.001), together with multiorgan resection and smoking status. ROC curve analyses supported the discriminatory performance of CRP, particularly on POD3. CONCLUSION: PPAP is a rare but potentially severe complication after DP. Among patients with POH, elevated early postoperative CRP, particularly on POD3, may allow early risk stratification, identifying those at high risk of PPAP who may benefit from targeted mitigation strategies.