How do you grade the severity of pancreatitis?

Grading Severity of Pancreatitis

The most effective approach to grade pancreatitis severity is to use the Bedside Index of Severity in Acute Pancreatitis (BISAP) score due to its simplicity and accuracy in predicting severity, mortality, and organ failure comparable to more complex scoring systems. 1

Clinical Scoring Systems

BISAP Score

• BISAP evaluates five parameters within 24 hours of admission: Blood urea nitrogen >25 mg/dl, Impaired mental status, Systemic inflammatory response syndrome (SIRS), Age >60 years, and Pleural effusion on radiography 1
• A BISAP score of ≥2 is a statistically significant cutoff value for diagnosing severe acute pancreatitis, organ failure, and mortality 2
• BISAP has similar accuracy to APACHE-II but is much simpler to calculate at the bedside 3, 4

APACHE-II Score

• Evaluates chronic health score and 12 physiologic measurements, providing comprehensive assessment but more complex to calculate 1, 5
• A score of ≥8 indicates severe acute pancreatitis 1
• APACHE-II score of ≥6 has 95% sensitivity for detecting complications but only 50% positive predictive value 1
• Can be used for ongoing daily assessment to monitor disease progression or recovery 1

Ranson/Glasgow Scoring Systems

• Multifactor scoring systems with 70-80% accuracy in predicting severity 1
• Three or more positive Glasgow criteria within 48 hours constitutes severe disease 1
• Requires 48 hours to complete, which delays risk stratification 1

Laboratory Markers

• C-reactive protein (CRP) is a valuable prognostic indicator 1

  • Peak level >210 mg/l in first four days (or >120 mg/l at end of first week) indicates severe disease with 80% accuracy 1
  • CRP ≥150 mg/l on day 3 can be used as a prognostic factor for severe acute pancreatitis 1

• Other important laboratory markers:

  • Hematocrit >44% is an independent risk factor for pancreatic necrosis 1
  • Blood urea nitrogen (BUN) >20 mg/dl is an independent predictor of mortality 1
  • Procalcitonin is highly sensitive for detecting pancreatic infection, with low values being strong negative predictors of infected necrosis 1

Radiological Assessment

CT Severity Index (CTSI)

• Dynamic contrast-enhanced CT scan should be performed in all severe cases between 3-10 days after admission 1
• CTSI combines assessment of pancreatic inflammation and necrosis 1
• Scoring ranges from 0-10 based on:
  • Pancreatic inflammation grade (0-4 points)
  • Extent of pancreatic necrosis (0-6 points) 1
• CTSI correlates with morbidity and mortality:
  • 0-1: minimal morbidity and mortality
  • 2-3: 8% morbidity, 3% mortality
  • 4-6: 35% morbidity, 6% mortality
  • 7-10: 92% morbidity, 17% mortality 1

Organ Failure Assessment

• The presence of organ failure (pulmonary, circulatory, or renal insufficiency) clinically indicates a severe attack according to the Atlanta definitions 1
• Persistent organ failure (>48 hours) defines severe acute pancreatitis in the latest Atlanta classification 6

Practical Approach to Severity Grading

1. Calculate BISAP score within first 24 hours of admission 1
2. Measure CRP levels (ideally on day 3) 1
3. Perform contrast-enhanced CT scan between days 3-10 in patients with predicted severe disease 1
4. Monitor for development of organ failure 1

Common Pitfalls and Caveats

• Clinical assessment alone is unreliable and will misclassify approximately 50% of patients 1
• No single method of prediction is perfect - none will predict all patients who will develop later complications 1
• Many patients initially classified as severe will have uncomplicated recovery 1
• Most severity scores take more than 24 hours to stratify patients, potentially causing delay in critical cases 1
• CT severity does not necessarily predict the need for surgery, as it doesn't accurately predict the degree of pancreatic necrosis 1