HAPS Score

Harmless Acute Pancreatitis Score — Early Triage at Admission

A 3-parameter score assessed at admission (not 48h) to identify patients who will have a harmless course of acute pancreatitis. A score of 0 predicts a complication-free course with 99.2% negative predictive value.

General Surgery Pancreatitis Emergency Medicine

HAPS Score (at Admission)

Check each ABNORMAL finding present at admission

Rebound tenderness or muscular guarding on abdominal exam +1 Abnormal haematocrit (Hct <43% in males or <39.6% in females) +1 Elevated serum creatinine (>177 µmol/L / >2.0 mg/dL) +1

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HAPS Score / 3

Select criteria above and calculate

Score Interpretation

Score	Prediction	Action
0	Harmless course (NPV 99.2%)	Early diet; consider short stay protocol
1	Cannot exclude complications	Active monitoring; imaging if uncertain
2–3	Complicated course likely	Admit; full severity assessment at 48h

Clinical Application

HAPS is the only severity score validated at admission (not 48h like Glasgow/Ranson)
Designed for early triage: HAPS = 0 allows safe discharge or short-stay protocol
Three criteria reflect early physiological stress: peritonism (guarding), dehydration/haemoconcentration (Hct), and renal impairment (creatinine)
Original derivation: 1119 patients, Lankisch et al. 2009; NPV 99.2% for serious complications
Combine with clinical severity at 24–48h using Glasgow Score for comprehensive assessment
HAPS does NOT replace imaging: CT is required if diagnosis uncertain or if no improvement
For HAPS = 0: early oral refeeding safe; reduces length of stay without increasing complications
Haematocrit: haemoconcentration at admission is a strong predictor of pancreatic necrosis

Pancreatitis Scoring Comparison

Score	Timing	Parameters	Purpose	Key Metric
HAPS	Admission	3	Identifies harmless course	NPV 99.2%
BISAP	24h	5	Predicts mortality	Score ≥3 = high risk
Glasgow (Imrie)	48h	8	Defines severe acute pancreatitis	≥3 = severe
Modified CTSI	Imaging (CT)	10 points	Necrosis + fluid collections	Correlates with morbidity

References

Lankisch PG, et al. The harmless acute pancreatitis score: a clinical algorithm for rapid initial stratification of nonsevere disease. Clin Gastroenterol Hepatol. 2009;7(6):702–705.
Mounzer R, et al. Comparison of existing clinical scoring systems to predict persistent organ failure in patients with acute pancreatitis. Gastroenterology. 2012.

HAPS Score

Score Interpretation

Clinical Application

Pancreatitis Scoring Comparison

References

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