Clinical relevance of the revised Atlanta classification focusing on severity stratification system

Abstract

Background/objective: Recognizing the limitation of the Atlanta classification for acute pancreatitis (AP), two international classifications have been recently proposed; the revised Atlanta classification and the determinant-based classification. There is an inconsistency between the two international classifications on whether infected necrosis (IN) is the major determinant of severity in AP. The aim of the current study was to validate the revised Atlanta classification and to determine the association of this new classification system with relevant clinical outcome in patients with AP.

Methods: Data have been collected on 553 patients with AP admitted to a single center during the 7-year period commencing January 2006. Primary outcomes included the need for interventions, the need for intensive care unit (ICU) care, length of ICU stay, total hospital stay, and mortality.

Results: The different grades of severity for revised Atlanta classification system were associated with statistically significant differences in terms of clinical outcomes. Patients with severe AP that had IN, compared to those without IN, were associated with worse clinical outcomes. Having stratified patients with severe AP category according to the presence or absence of IN, the mortality rate increased fourfold to 32.3% for the presence of infected necrosis.

Conclusions: Overall, the revised Atlanta classification seems to be valid, since it correlates well with clinical outcome. To more accurately assess clinical outcome of patients with severe AP defined by the revised Atlanta classification, however, severe AP patients with IN should be considered separately from those without IN in classification system.

Keywords: Classification; Morbidity; Mortality; Necrosis; Organ failure; Pancreatitis.