Predicting Severity in Acute Pancreatitis: A Never-Ending Quest…

Acute pancreatitis (AP) is one of the leading causes of hospital admission of gastrointestinal origin, with a reported annual incidence ranging from 4.6 to 100 per 100,000 in Europe [1]. Its incidence appears to be rising, with a median increase of 3.4% per year [1], most likely due to the obesity epidemic and its relationship with gallstones. The revised Atlanta classification [2] divides this entity into interstitial edematous and necrotizing AP, based on the absence or presence of tissue necrosis. Furthermore, the disease is graded according to its severity into mild, moderate, and severe. This classification relies on the presence of organ failure (transient or persistent) and local or systemic complications. The definite grade of severity requires reassessment, which is advisable at 24 h, 48 h, and 7 days after admission. The importance of severity prediction is well established. A precise assessment of severity would downsize the financial burden of AP, as mild AP does not require inpatient treatment or pancreatic imaging. Also, it is expected to decrease mortality and morbidity, as it would aid in the triage for intensive care units. Accurately defining and predicting the severity of the disease early on in its course has historically been a daunting task. Multiple scoring systems have been developed based on clinical, laboratory, and radiologic findings. Most models are based on data from two points in time (i.e., at admission and 48 h), rendering them impossible to use in a triage setting. Other scoring systems are timeconsuming, making it difficult to implement them in the emergency department. Moreover, most algorithms have failed to achieve reasonable predictive values [3]. Probably one of the most recognized scoring systems, Ranson’s criteria, requires parameters assessed at admission and at 48 h and, although still widely used, it is a poor predictor of severity [4]. The Imrie or Glasgow score is a simplified version of Ranson’s criteria but has the same disadvantages. The Bedside Index of Severity in Acute Pancreatitis (BISAP) score is easy to use and incorporates