Ranson’s Criteria Calculator
Ranson's Criteria Calculator
Score acute pancreatitis severity on the correct parameter set for the aetiology, with the admission and 48-hour subtotals shown separately.
Ranson's criteria
Aetiology + 11 items → pointsNon-gallstone. Age 58, WBC 18.5 ×10⁹/L, glucose 180 mg/dL, AST 180 IU/L, LDH 320 IU/L; at 48 h calcium 7.6 mg/dL, haematocrit fall 6 points, BUN rise 3 mg/dL, base deficit 2.5 mEq/L, 3 L sequestered, PaO₂ 72 mmHg
Scoring
Predicted severe = more than 2 points
- Admission, non-gallstone
- age > 55 · WBC > 16 ×10⁹/L · glucose > 200 mg/dL · AST > 250 IU/L · LDH > 350 IU/L
- Admission, gallstone
- age > 70 · WBC > 18 ×10⁹/L · glucose > 220 mg/dL · AST > 250 IU/L · LDH > 400 IU/L
- 48 hours, non-gallstone
- calcium < 8 mg/dL · haematocrit fall > 10% · PaO₂ < 60 mmHg · BUN rise ≥ 5 mg/dL · base deficit > 4 mEq/L · fluid sequestration > 6 L
- 48 hours, gallstone
- calcium < 8 mg/dL · haematocrit fall > 10% · BUN rise ≥ 2 mg/dL · base deficit > 5 mEq/L · fluid sequestration > 4 L — no PaO₂ criterion
- Maximum
- 11 points non-gallstone, 10 points gallstone
Worked example
Non-gallstone. Age 58, WBC 18.5 ×10⁹/L, glucose 180 mg/dL, AST 180 IU/L, LDH 320 IU/L; at 48 h calcium 7.6 mg/dL, haematocrit fall 6 points, BUN rise 3 mg/dL, base deficit 2.5 mEq/L, 3 L sequestered, PaO₂ 72 mmHg
Admission: age 58 > 55 (1) + WBC 18.5 > 16 (1) + glucose 180 not > 200 (0) + AST 180 not > 250 (0) + LDH 320 not > 350 (0) = 2
48 hours: calcium 7.6 < 8 (1) + haematocrit fall 6 not > 10 (0) + BUN rise 3 not ≥ 5 (0) + base deficit 2.5 not > 4 (0) + 3 L not > 6 L (0) + PaO₂ 72 not < 60 (0) = 1
2 + 1 = 3 points → published mortality about 15%
The two parameter sets
| Criterion | Non-gallstone | Gallstone |
|---|---|---|
| Age (admission) | > 55 | > 70 |
| White cell count (admission) | > 16 ×10⁹/L | > 18 ×10⁹/L |
| Glucose (admission) | > 200 mg/dL | > 220 mg/dL |
| AST (admission) | > 250 IU/L | > 250 IU/L |
| LDH (admission) | > 350 IU/L | > 400 IU/L |
| Calcium (48 h) | < 8 mg/dL | < 8 mg/dL |
| Haematocrit fall (48 h) | > 10% | > 10% |
| BUN rise (48 h) | ≥ 5 mg/dL | ≥ 2 mg/dL |
| Base deficit (48 h) | > 4 mEq/L | > 5 mEq/L |
| Fluid sequestration (48 h) | > 6 L | > 4 L |
| PaO₂ (48 h) | < 60 mmHg | not a criterion |
| Maximum score | 11 | 10 |
The three scores compared
| Score | Scored when | Items | Outcome it was derived against |
|---|---|---|---|
| Ranson's | Split: admission and 48 hours | 11 (10 for gallstones) | Mortality and complications, 1974 |
| BISAP | First 24 hours | 5 | In-hospital mortality, 2008 |
| Glasgow-Imrie | 48 hours | 8 | Severe disease, 1984 |
Why a 48-hour score is a 48-hour problem
Ranson's criteria were derived at New York University in the early 1970s and published in 1974, and they did something genuinely new: they gave a numerical answer to the question of which patient with acute pancreatitis was going to have a bad time. Fifty years later the score is still taught, still on the wards, and largely superseded — and the reason is built into its own structure.
Five of the eleven items are measured on admission and six at 48 hours. The score is not complete until the second set is back. But the decisions the score was meant to inform — how aggressively to resuscitate, whether to involve critical care, whether to transfer — have all been made by then, one way or another, on clinical grounds. A prognostic instrument that reports after the decision point is a research tool, not a bedside one. That is the single criticism that has stuck, and it is why the two subtotals are shown separately above rather than buried in one number.
Three developments have taken its place. BISAP uses five items inside the first 24 hours and matches APACHE II for discrimination, which is the practical answer to the timing problem. APACHE II is calculable continuously and is the reference standard in trials, at the cost of needing a dozen physiological variables. And the revised Atlanta classification of 2012 changed the question: severity is now defined as persistent organ failure beyond 48 hours, with moderately severe disease being transient organ failure or local complications, and mild disease being neither. Once severity has a definition, a score that predicts it is a different and smaller thing.
The aetiology split is the detail most reproductions get wrong. Ranson published a separate parameter set for gallstone pancreatitis, with a higher age threshold, higher white cell and glucose and LDH thresholds, a lower BUN and base deficit and fluid threshold, and — the part that is usually lost — no PaO₂ criterion at all. The gallstone version therefore has ten items, not eleven, and the same raw findings can give different totals depending on which set is applied. Applying the alcohol thresholds to a patient with gallstones overcalls the score; applying the gallstone thresholds to an alcohol-related presentation undercalls it.
What Ranson's still does well is force a structured 48-hour review. The items are not arbitrary: a falling calcium, a rising urea despite fluids, a falling haematocrit and a widening base deficit are between them a reasonable sketch of third-space loss and evolving organ dysfunction. Scored as a checklist rather than as a prediction, that remains useful. Compare it against Glasgow-Imrie, which is also a 48-hour score and is the one UK guidance has historically specified.
Frequently asked questions
What Ranson score means severe pancreatitis?
More than 2 points is the conventional threshold for predicted severe disease. Reported performance at that cut-off varies: one pooled analysis gives median sensitivity 90% and specificity 67.4%, another gives 86.6% and 87.2%. Published mortality is 0 to 3% at 0 to 2 points, about 15% at 3 to 4, about 40% at 5 to 6, and approaching 100% above that in the original series.
Why are the gallstone thresholds different?
Ranson derived a separate set for biliary pancreatitis because the same raw values carried different prognostic weight. Age, white cells, glucose and LDH all move up; BUN rise, base deficit and fluid sequestration move down; and PaO₂ drops out entirely, leaving ten items rather than eleven.
Can I score Ranson's on admission?
You can score the five admission items, and that is what the admission subtotal above shows, but the total is not a Ranson score until the 48-hour items are available. Six further points are still in play. If you need a score within the first day, BISAP was designed for exactly that.
Has Ranson's been replaced?
Largely, for decision-making. BISAP gives comparable discrimination inside 24 hours, APACHE II remains the trial standard, and the revised Atlanta classification now defines severity by persistent organ failure rather than predicting it. Ranson's survives as a structured 48-hour review and as the historical reference other scores are measured against.
Related calculators
References
- Ranson JHC, Rifkind KM, Roses DF, Fink SD, Eng K, Spencer FC. Prognostic signs and the role of operative management in acute pancreatitis. Surg Gynecol Obstet. 1974;139(1):69–81.
- Ranson Criteria. StatPearls. NCBI Bookshelf NBK482345 (archived).
- Banks PA, Bollen TL, Dervenis C, et al. Classification of acute pancreatitis—2012: revision of the Atlanta classification and definitions by international consensus. Gut. 2013;62(1):102–11.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.