This harmless acute pancreatitis score (HAPS) calculator helps clinicians rule out patients who suffer from pancreatic episode but don’t require intensive care. The text below the form provides information on the criteria used in the score and on how the result is interpreted.


Rebound tenderness/guarding


Creatinine ≥2 mg/dL (177 µmol/L)


Hematocrit ≥43% (male) or 39.6% (female)

How does the harmless acute pancreatitis score (HAPS) calculator work?

This health tool is based on the HAPS system devised in 2009 to establish the benign course in acute pancreatitis.

Was developed with the use of retrospective studies and is recommended to be applied to patients within 30 minutes of admission to delineate the likely severity of the pancreatic episode.

The harmless acute pancreatitis score (HAPS) calculator looks at the following three variables in order to rule out attacks of severe pancreatitis:

■ Rebound tenderness/guarding – characteristic sign of AP, which comes along upper abdominal pain;

■ Creatinine – laboratory investigation, increased serum enzymes are a sign of damage due to pancreatitis;

■ Hematocrit – laboratory investigation, early admission marker of severe and/or necrotizing pancreatitis.

HAPS is aimed at low risk patients, for which the score has a high predictive value. It can be used to differentiate between patients who require immediate ICU care and those who don’t.

The cohort of patients has been categorized based on the cause of the pancreatic attack, from alcoholic, biliary and idiopathic to other.

The original score has 97% specificity and 98% predictive value in ruling out pancreatic necrosis, need for dialysis, artificial ventilation or fatal outcome.

The score however remains subject to clinical judgement.

HAPS interpretation

In terms of score interpretation, it is considered that the absence of all three criteria rules out pancreatic necrosis, related complications or fatal outcome. The presence of one, two or all three criteria, on the other hand, means that ICU admission may be possible and the patient needs further investigation.

One of the main benefits of the score is the fact that it can be applied in a timely manner after admission. It is believed that an experienced physician can successfully stratify mild from severe acute pancreatitis after 24 hours from presentation, based on the development of symptoms.

Predicting the severity of acute pancreatitis

The pancreatitis diagnosis is recognized for its difficulty and it can often be time consuming to wait for the laboratory results and CT investigations, very serious in the case of a disease with significant morbidity and mortality.

It is estimated that around 15 to 25% of patients with AP develop severe acute pancreatitis and the stratification of the severity is essential in offering the right treatment as soon as possible.

One study has focused on the predictive value of the red cell distribution width (RDW) which is a known prognostic marker, in stratifying AP. Some argue that this can be used in conjunction with HAPS.

There are other studies that address the likelihood of severe AP in patients with high risk of pancreatitis. For example, the Glasgow Pancreatitis Score focuses on laboratory investigations that are known as AP markers, such as: serum albumin, blood glucose, serum LDH or urea nitrogen.

Similarly, BISAP score takes other risk factors, such as SIRS criteria present, pleural effusion, BUN to investigate the risk of complications within 24 hours.

The Balthazar score looks at the grading and necrosis percentage when that is present.

Other tools, such as the Ranson Criteria can be used as a prediction tool for mortality risk, based on AST, LDH, WBC or blood glucose levels.

Beside this, clinicians are recommended to use other tools, such as the APACHE II score or the Sequential Organ Failure Assessment (SOFA) to stratify the disease severity in intensive care units.


1) Lankisch PG, Weber-Dany B, Hebel K, Maisonneuve P, Lowenfels AB. (2009) The harmless acute pancreatitis score: a clinical algorithm for rapid initial stratification of nonsevere disease. Clin Gastroenterol Hepatol; 7(6):702-5.

2) Oskarsson V, Mehrabi M, Orsini N, Hammarqvist F, Segersvärd R, Andrén-Sandberg A, Sadr Azodi O. (2011) Validation of the Harmless Acute Pancreatitis Score in Predicting Nonsevere Course of Acute Pancreatitis. Pancreatology; 11(5), 464-468.

3) Gülen B, Sonmez E, Yaylaci S, Serinken M, Eken C, Dur A, Turkdogan FT, Söğüt O. (2015) Effect of harmless acute pancreatitis score, red cell distribution width and neutrophil/lymphocyte ratio on the mortality of patients with nontraumatic acute pancreatitis at the emergency department. World J Emerg Med; 6(1): 29–33.

4) Parekh R, Zalawadia A, Dave A, Ambulgekar N, Buran G. (2011) Harmless Acute Pancreatitis Score (Haps) As an Initial Predictor of Nonsevere Disease in Acute Pancreatitis. SHM Annual Meeting 2011; 91.

14 Nov, 2016