BISAP Score Calculator for Acute Pancreatitis
Record the five-item adult BISAP early prognostic score from the first 24 hours of an established acute-pancreatitis hospitalization.
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Use this adult BISAP implementation after acute pancreatitis has already been established clinically. Score the five findings from the first 24 hours of the same hospitalization. BISAP does not diagnose acute pancreatitis.
This calculator cannot verify chart timing, hospitalization identity, diagnosis, imaging, or data provenance. Do not mix different admissions, late deterioration, or later post-treatment findings into this first-24-hour assessment.
BISAP Score Criteria
Each finding contributes 1 point; total 0–5. The mmol/L value is an approximate reference only—numeric entry and runtime comparison remain in mg/dL.
| Item | One-point finding | Points |
|---|---|---|
| B | BUN >25 mg/dL (approximately >8.9 mmol/L) | 1 |
| I | Impaired mental status | 1 |
| S | SIRS ≥2 criteria | 1 |
| A | Age >60 years | 1 |
| P | Pleural effusion | 1 |
Five BISAP score criteria
- Item
- B
- One-point finding
- BUN >25 mg/dL (approximately >8.9 mmol/L)
- Points
- 1
- Item
- I
- One-point finding
- Impaired mental status
- Points
- 1
- Item
- S
- One-point finding
- SIRS ≥2 criteria
- Points
- 1
- Item
- A
- One-point finding
- Age >60 years
- Points
- 1
- Item
- P
- One-point finding
- Pleural effusion
- Points
- 1
About
BISAP is Wu’s 2008 five-item early prognostic score for adults with an established acute pancreatitis hospitalization. It uses the first 24 hours of the same admission: BUN, impaired mental status, classic SIRS status, completed age, and pleural effusion. It is a population-derived prognostic ranking tool, not a diagnosis of pancreatitis, a personal mortality probability, a Revised Atlanta severity class, or a treatment or level-of-care rule. [1, 2]
This page records only the values explicitly submitted by the user. It cannot verify chart timing, hospitalization identity, diagnosis, imaging, or data provenance. It does not calculate a full GCS or SIRS assessment, classify organ failure, or choose fluids, nutrition, antibiotics, ERCP, surgery, monitoring, or ICU care. ACG 2024 emphasizes ongoing clinical assessment because a score or imaging result alone is not enough to predict moderately severe or severe acute pancreatitis. [3, 4, 5]
Interpretation
These static historical proportions are shown for context from specific derivation, validation, and comparison cohorts; no row is highlighted and no proportion is attached to an individual result. [1, 2, 3]
| BISAP score | Observed historical proportion |
|---|---|
| 0–1 | 0.1–0.7% |
| 2 | 1.9–2.1% |
| 3 | 5.3–8.3% |
| 4 | 12.7–19.3% |
| 5 | 22.5–26.7% |
Historical in-hospital mortality proportions by BISAP score
- BISAP score
- 0–1
- Observed historical proportion
- 0.1–0.7%
- BISAP score
- 2
- Observed historical proportion
- 1.9–2.1%
- BISAP score
- 3
- Observed historical proportion
- 5.3–8.3%
- BISAP score
- 4
- Observed historical proportion
- 12.7–19.3%
- BISAP score
- 5
- Observed historical proportion
- 22.5–26.7%
The observed ranges are not current personal probabilities. A score of ≥3 is a common research threshold, not an automatic ICU, treatment, admission, or discharge rule; meta-analysis found limited sensitivity, so a lower score cannot exclude severe disease or death. ACG 2024 states that scoring systems or imaging alone are insufficient to predict who will develop moderately severe or severe disease. [4, 7, 8]
Revised Atlanta context — not calculated
Revised Atlanta requires at least two of characteristic abdominal pain, serum lipase or amylase at least three times the upper limit, and characteristic imaging. Its mild, moderately severe, and severe categories depend on organ-failure duration and local or systemic complications; persistent organ failure is more than 48 hours. BISAP cannot generate those categories. [4, 5]
BISAP criteria, first-24-hour boundaries, and clinical limits
Five-item scoring boundaries
The complete BISAP Score Criteria table appears inside the calculator tool so it is available before entry. Each assessed present finding contributes one point; missing findings are not inferred as absent. The authoritative numeric BUN input remains mg/dL, with 25 exactly scoring zero, and completed age 60 also scoring zero. [1]
Classic SIRS within BISAP
Classic SIRS background uses temperature >38°C or <36°C, heart rate >90/min, respiratory rate >20/min or PaCO₂ <32 mmHg, and WBC >12,000/mm³, <4,000/mm³, or >10% immature forms. At least two satisfy the historical aggregate item. This page records an external first-24-hour assessment; it does not calculate the four inputs. SIRS is not synonymous with infection and is not the modern Sepsis-3 diagnosis. [1, 6]
| Classic item | Threshold |
|---|---|
| Temperature | >38°C or <36°C |
| Heart rate | >90/min |
| Respiratory / PaCO₂ | >20/min or PaCO₂ <32 mmHg |
| White-cell count | >12,000/mm³, <4,000/mm³, or >10% immature forms |
Classic SIRS criteria used as BISAP background
- Classic item
- Temperature
- Threshold
- >38°C or <36°C
- Classic item
- Heart rate
- Threshold
- >90/min
- Classic item
- Respiratory / PaCO₂
- Threshold
- >20/min or PaCO₂ <32 mmHg
- Classic item
- White-cell count
- Threshold
- >12,000/mm³, <4,000/mm³, or >10% immature forms
What the calculator actually does
- Reads BUN availability and value, mental-status assessment, external SIRS aggregate, completed age, and pleural-effusion assessment.
- Adds one point for each present criterion using the validated implementation.
- Withholds the total when any component is unavailable, while retaining a five-item audit.
Use it only after adult acute pancreatitis has been established and only with findings from the first 24 hours of the same hospitalization. It does not verify those facts, read records or images, calculate GCS or SIRS, diagnose pancreatitis, classify organ failure, generate Revised Atlanta severity, calculate APACHE II/Ranson/CTSI, or choose treatment or care location. [1, 4]
BISAP and related acute-pancreatitis frameworks
BISAP is a first-24-hour five-item early prognostic score. Revised Atlanta uses organ-failure duration and local/systemic complications; APACHE II uses broader acute physiology; Ranson has a different admission and later time structure; CTSI/mCTSI depends on imaging morphology. These frameworks answer different questions and cannot be converted into one another. [3, 4, 5]
| Tool | Time frame | Main inputs | Primary purpose / why not interchangeable |
|---|---|---|---|
| BISAP | First 24 hours | BUN, mental status, classic SIRS, age, pleural effusion | Five-item early prognostic score; not formal severity classification |
| Revised Atlanta | Early and late disease phases | Organ-failure duration and local/systemic complications | Defines mild, moderately severe, and severe disease; not a point score |
| APACHE II | Physiologic severity assessment | Broader acute physiology, age, and chronic health items | Different inputs and timing; cannot be converted from BISAP |
| Ranson | Admission and later time points | Different clinical and laboratory criteria | Different time structure and endpoint |
| CTSI / mCTSI | Imaging-based assessment | Pancreatic inflammation and necrosis imaging features | Requires imaging morphology; not calculated here |
Comparison of BISAP and acute pancreatitis frameworks
- Tool
- BISAP
- Time frame
- First 24 hours
- Main inputs
- BUN, mental status, classic SIRS, age, pleural effusion
- Primary purpose / why not interchangeable
- Five-item early prognostic score; not formal severity classification
- Tool
- Revised Atlanta
- Time frame
- Early and late disease phases
- Main inputs
- Organ-failure duration and local/systemic complications
- Primary purpose / why not interchangeable
- Defines mild, moderately severe, and severe disease; not a point score
- Tool
- APACHE II
- Time frame
- Physiologic severity assessment
- Main inputs
- Broader acute physiology, age, and chronic health items
- Primary purpose / why not interchangeable
- Different inputs and timing; cannot be converted from BISAP
- Tool
- Ranson
- Time frame
- Admission and later time points
- Main inputs
- Different clinical and laboratory criteria
- Primary purpose / why not interchangeable
- Different time structure and endpoint
- Tool
- CTSI / mCTSI
- Time frame
- Imaging-based assessment
- Main inputs
- Pancreatic inflammation and necrosis imaging features
- Primary purpose / why not interchangeable
- Requires imaging morphology; not calculated here
Evidence, validation, and threshold limitations
Wu derived the score in a large population-based adult cohort, Singh prospectively evaluated it, and Gao’s systematic review and meta-analysis summarized multiple cohorts. Their endpoints and populations are not identical: studies examine mortality, organ failure, persistent organ failure, necrosis, or Revised Atlanta severity under different definitions. A common research threshold is ≥3, but sensitivity is not sufficient to use a lower score to rule out severe disease or death. The 2015 Gao publication is cited together with its formal Correction; no claim here guesses what the Correction changed or says it changed the BISAP algorithm. [1, 2, 7, 8]
Revised Atlanta and current guideline context
Acute pancreatitis diagnosis is a separate clinical process. Revised Atlanta uses at least two diagnostic features and defines mild, moderately severe, and severe disease by organ-failure duration and complications, including persistent organ failure beyond 48 hours. ACG 2024 emphasizes initial risk assessment plus ongoing clinical evaluation; neither BISAP nor imaging alone replaces that process. [4, 5]
Important limitations
Interpretation is limited by evolving organ failure, hemodynamics, hypoxemia or respiratory support, renal dysfunction and changing BUN, fluid treatment, pancreatic necrosis, local or systemic complications, obesity, comorbidity, etiology, infection, cholangitis, nutrition tolerance, pain, vomiting, oral intake, late deterioration, pregnancy, childhood, transfer, delayed presentation, mixed admissions, sedation, intubation, confounded mental status, and missing imaging. A low score cannot exclude later deterioration; a high score cannot decide ICU or treatment. Do not wait for an online calculator in an unstable patient. [2, 4, 5]
References
- Wu BU, Johannes RS, Sun X, Tabak Y, Conwell DL, Banks PA. The early prediction of mortality in acute pancreatitis: a large population-based study. Gut. 2008;57(12):1698–1703. PMID 18519429. DOI 10.1136/gut.2008.152702.
- Singh VK, Wu BU, Bollen TL, et al. A prospective evaluation of the bedside index for severity in acute pancreatitis score in assessing mortality and intermediate markers of severity in acute pancreatitis. Am J Gastroenterol. 2009;104(4):966–971. PMID 19293787. DOI 10.1038/ajg.2009.28.
- Papachristou GI, Muddana V, Yadav D, et al. Comparison of BISAP, Ranson's, APACHE-II, and CTSI scores in predicting organ failure, complications, and mortality in acute pancreatitis. Am J Gastroenterol. 2010;105(2):435–441. PMID 19861954. DOI 10.1038/ajg.2009.622.
- Tenner S, Vege SS, Sheth SG, et al. American College of Gastroenterology Guidelines: Management of Acute Pancreatitis. Am J Gastroenterol. 2024;119(3):419–437. PMID 38857482. PMCID PMC13221274. DOI 10.14309/ajg.0000000000002645.
- 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):102–111. PMID 23100216. DOI 10.1136/gutjnl-2012-302779.
- Bone RC, Balk RA, Cerra FB, et al. Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. Chest. 1992;101(6):1644–1655. PMID 1303622. DOI 10.1378/chest.101.6.1644.
- Gao W, Yang H-X, Ma C-E. The Value of BISAP Score for Predicting Mortality and Severity in Acute Pancreatitis: A Systematic Review and Meta-Analysis. PLoS One. 2015;10(6):e0130412. PMID 26091293. DOI 10.1371/journal.pone.0130412.
- Gao W, Yang H-X, Ma C-E. Correction: The Value of BISAP Score for Predicting Mortality and Severity in Acute Pancreatitis: A Systematic Review and Meta-Analysis. PLoS One. 2015;10(10):e0142025. PMID 26513663. DOI 10.1371/journal.pone.0142025.
FAQ
This page reproduces Wu 2008’s five-item BISAP early prognostic score for an adult established acute-pancreatitis hospitalization during its first 24 hours. It is not a diagnostic, severity-classification, or treatment tool.
Sources: [1]
The original criterion is strictly greater than 25 mg/dL. A BUN of 25, including 25.000, is absent; a value greater than 25 is present.
Sources: [1]
The age criterion is strictly greater than 60 completed years. Age 60 is absent and age 61 is present.
Sources: [1]
The original BISAP definition uses disorientation or a more severe mental-status abnormality. GCS can support documentation, but GCS below 15 is not the only permitted definition and this page does not calculate a full GCS.
Sources: [1]
It means at least one original component was unavailable or could not be assessed reliably. The page retains the known audit items but never treats an unknown component as zero or presents a partial score.
Sources: [1]
BISAP is a five-item early score. APACHE II is a broader physiologic score and Ranson's criteria use a different time structure; they are not interchangeable.
Sources: [3]
Related Calculators
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Count the classic 1992 adult systemic inflammatory response criteria from submitted measurements, without diagnosing sepsis.
GCS
Record standard Glasgow Coma Scale eye, verbal, and motor responses, calculate a complete score when all are testable, and preserve Not Testable components without a fabricated total.
APACHE II
Reproduce the 1985 adult general-ICU APACHE II severity score from worst first-24-hour physiology, age and defined chronic-health points.
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.