Abstract
The case mortality for acute pancreatitis in the UK has remained largely unchanged, at just under 10% for the last 30 years. This is despite improvements in intensive therapy, radiology and surgical interventions. Acute pancreatitis also remains unpredictable. Organ system failure and pancreatic collections may develop either suddenly, or insidiously, and thus go undetected. Reducing mortality depends on better understanding of pathophysiology and more specific therapeutic approaches, but prognostic systems for the early identification of severe attacks may improve the success of current supportive therapies. Prognostic systems are also useful to compare clinical series and stratify severity in therapeutic trials. The multiple criteria of Ranson and Imrie predominate, but offer limited accuracy, involve delay, are cumbersome, and provide a one-off overall prediction. Internationally agreed definitions of complications demand accurate risk assessment for individual complications, while serial monitoring of severity is needed to assess progress and to detect subtle changes after therapeutic intervention. Laboratory methods now provide equal, or improved, accuracy and speed compared to traditional criteria, and may be repeated serially. Growing knowledge of the systemic inflammatory response syndrome (SIRS) and the availability of response modifiers suggests that inflammatory mediators may prove to be the most useful and accurate means of assessment of severity.