title: Revised Atlanta and determinant-based classification: application in a prospective cohort of acute pancreatitis patients.
abstract: OBJECTIVE
  Atlanta classification (Atlanta 1992) of acute pancreatitis (AP) has several limitations. Two new classification systems were recently proposed: the Atlanta reclassification (Atlanta 2012) and the determinant-based classification (DBC). The aim of our study was to: (i) determine the association between different severity categories and clinical outcomes and (ii) perform a head-to-head comparison between Atlanta 1992, Atlanta 2012, and DBC in predicting these clinical outcomes.
  
  
  METHODS
  A total of 256 prospectively enrolled patients were assigned a severity category for all three classifications. Five clinical outcomes were evaluated: mortality, intensive care unit (ICU) admission and length of stay (LOS), need for interventions, and hospital LOS. Pairwise testing between severity grades within a classification system was performed using Fisher's exact and Kruskal-Wallis tests. Predictive accuracies were evaluated using area under the ROC curve (AUC) and Somer's D co-efficient.
  
  
  RESULTS
  Overall, higher grades of severity were associated with worse clinical outcomes for all three classification systems. Atlanta 2012 and DBC performed better than Atlanta 1992 and were comparable in predicting mortality (AUC 0.89 for both vs. 0.76, P<0.001), ICU admission (AUC 0.91 for both vs. 0.80, P<0.001), and ICU LOS (Somer's D 0.21 and 0.28 vs. 0.07, P<0.05). DBC performed better in predicting need for interventions (AUC 0.93 vs. 0.85, P<0.001), whereas Atlanta 2012 performed better in predicting hospital LOS (Somer's D 0.43 vs. 0.37, P=0.04).
  
  
  CONCLUSIONS
  Atlanta 2012 and DBC severity categories accurately reflected clinical outcomes in our cohort and were superior to Atlanta 1992. These novel classification systems can guide the selection of homogeneous patient populations for clinical research and provide an accurate spectrum of disease severity categories in the clinical setting.
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Haq
authors.initials: H
authors.lastname: Nawaz
authors.forename: Rawad
authors.initials: R
authors.lastname: Mounzer
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Yadav
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Yabes
authors.forename: Adam
authors.initials: A
authors.lastname: Slivka
authors.forename: David C
authors.initials: DC
authors.lastname: Whitcomb
authors.forename: Georgios I
authors.initials: GI
authors.lastname: Papachristou
mesh_terms: D003287:Contrast Media; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000145:classification* / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy; D011446:Prospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media