Synchronous Organ Failure and Infected Pancreatic Necrosis Define Genuine Critical Acute Pancreatitis

Abstract Background: The determinant-based classification (DBC) of acute pancreatitis (AP) was proposed in 2012. One of the highlights of the DBC was critical acute pancreatitis (CAP), which was supposed to be strongly associated with the highest risk of adverse outcomes. However, the definition of CAP needs to be further clarified.Methods: A prospective cohort with consecutive patients of infected pancreatic necrosis (IPN) at a tertiary hospital was analyzed. Patients were assigned to IPN alone, Metachronous-CAP (MCAP) and Synchronous-CAP group (SCAP) according to presence or absence of organ failure (OF) and the crosstalk between OF and IPN. Clinical interventions and outcomes were compared among groups.Results: A total of 248 IPN patients were enrolled and the overall mortality was 25.8%. Compared with MCAP, patients with SCAP were associated with higher mortality (45/68, 66.2% vs. 5/50, 10.0%; OR= 17.6,95% CI, 6.2-50.4; P < 0.001) and morbidity (28/68, 41.2% vs. 9/50, 18.0%; P = 0.013), longer duration of OF (median 35.5 days vs. 12.0 days, P < 0.001), longer ICU length of stay (LOS) (median 28.0 days vs. 16.0 days, P = 0.001), longer hospital LOS (median 67.0 days vs. 60.0 days, P < 0.001) as well as earlier requirement for surgical interventions. The IPN alone and MCAP had comparable mortality (10.8% vs. 10.0%, P = 0.88), morbidity and hospital LOS, except that MCAP patients were characterized with longer duration of OF and ICU LOS (P< 0.05).Conclusions: SCAP, characterized with synchronous persistent OF and IPN, was associated with higher mortality and morbidity and should be defined as genuine CAP.