How severe is moderately severe acute pancreatitis? Clinical validation of revised 2012 Atlanta Classification

AIM: To explore the outcomes and the appropriate treatment for patients with moderately severe acute pancreatitis (AP). METHODS: Statistical analysis was performed on data from the prospectively collected database of 103 AP patients admitted to the Department of Surgery, Hospital of Lithuanian University of Health Sciences in 2008-2013. All patients were confirmed to have the diagnosis of AP during the first 24 h following admission. The severity of pancreatitis was assessed by MODS and APACHE II scale. Clinical course was re-evaluated after 24, 48 and 72 h. All patients were categorized into 3 groups based on Atlanta 2012 classification: Mild, moderately severe, and severe. Outcomes and management in moderately severe group were also compared to mild and severe cases according to Atlanta 1992 and 2012 classification. RESULTS: Fifty-three-point four percent of patients had edematous while 46.6 % were diagnosed with necrotic AP. The most common cause of AP was alcohol (42.7%) followed by alimentary (26.2%), biliary (26.2%) and idiopathic (4.9%). Under Atlanta 1992 classification 56 (54.4%) cases were classified as “mild” and 47 (45.6%) as “severe”. Using the revised classification (Atlanta 2012), the patient stratification was different: 49 (47.6%) mild, 27 (26.2%) moderately severe and 27 (26.2%) severe AP cases. The two severe groups (Atlanta 1992 and Revised Atlanta 2012) did not show statistically significant differences in clinical parameters, including ICU stay, need for interventional treatment, infected pancreatic necrosis or mortality rates. The moderately severe group of 27 patients (according to Atlanta 2012) had significantly better outcomes when compared to those 47 patients classified as severe form of AP (according to Atlanta 1992) with lower incidence of necrosis and sepsis, lower APACHE II (P = 0.002) and MODS (P = 0.001) scores, shorter ICU stay, decreased need for interventional and surgical treatment. CONCLUSION: Study shows that Atlanta 2012 criteria are more accurate, reduce unnecessary treatments for patients with mild and moderate severe pancreatitis, potentially resulting in health costs savings.