What parameters are needed to calculate the CLIF (Chronic Liver Failure) OF score in a patient with acute-on-chronic liver failure (ACLF), impaired renal function, elevated bilirubin, and coagulopathy?

CLIF-C OF Score Parameters

The CLIF-C Organ Failure (OF) score requires assessment of six organ systems: liver (bilirubin), kidney (creatinine), brain (hepatic encephalopathy grade), coagulation (INR), circulation (mean arterial pressure), and lungs (PaO2/FiO2 or SpO2/FiO2 ratio). 1

Required Laboratory and Clinical Parameters

Liver Function

• Serum bilirubin in mg/dL 1
  • 1 point: Bilirubin <6 mg/dL
  • 2 points: Bilirubin ≥6 to <12 mg/dL
  • 3 points: Bilirubin ≥12 mg/dL 1

Kidney Function

• Serum creatinine in mg/dL 1
  • 1 point: Creatinine <2 mg/dL
  • 2 points: Creatinine ≥2 to <3.5 mg/dL
  • 3 points: Creatinine ≥3.5 mg/dL 1

Brain/Neurological Function

• Hepatic encephalopathy grade using West Haven criteria 1
  • 1 point: Grade 0 (no encephalopathy)
  • 2 points: Grades 1-2
  • 3 points: Grades 3-4 1
• Important caveat: Patients on mechanical ventilation due to hepatic encephalopathy (not respiratory failure) are assigned a cerebral score of 3 1

Coagulation Function

• International Normalized Ratio (INR) 1
  • 1 point: INR <2.0
  • 2 points: INR ≥2.0 to <2.5
  • 3 points: INR ≥2.5 or platelet count ≤20,000/mm³ 1

Circulatory Function

• Mean arterial pressure (MAP) in mmHg 1
  • 1 point: MAP ≥70 mmHg
  • 2 points: MAP <70 mmHg
  • 3 points: Use of vasopressors (dopamine >5 μg/kg/min, epinephrine >0.1 μg/kg/min, or norepinephrine at any dose) 1

Respiratory Function

• PaO2/FiO2 ratio (arterial oxygen partial pressure/fraction of inspired oxygen) OR SpO2/FiO2 ratio (pulse oximetric saturation/fraction of inspired oxygen) 1
  • 1 point: PaO2/FiO2 >300 or SpO2/FiO2 >357
  • 2 points: PaO2/FiO2 ≤300 to >200, or SpO2/FiO2 ≤357 to >214
  • 3 points: PaO2/FiO2 ≤200 or SpO2/FiO2 ≤214 1
• Important caveat: Patients on mechanical ventilation for respiratory failure (not encephalopathy) are assigned a respiratory score of 3 1

Clinical Application

The CLIF-C OF score is the foundation for both ACLF grading and the CLIF-C ACLF prognostic score 1. The EASL guidelines emphasize that diagnosis and grading of ACLF should be based on assessment of organ function as defined by the CLIF-C Organ Failure score 1. This scoring system has been validated as superior to MELD, MELD-Na, and Child-Pugh scores for predicting short-term mortality in patients with acute decompensation of cirrhosis 1, 2.

Distinction from CLIF-C ACLF Score

While the CLIF-C OF score assesses organ failures alone, the CLIF-C ACLF score (used for prognostication) additionally requires patient age in years and white blood cell count 1, 3. The formula is: 10 × [0.033 × CLIF OF score + 0.04 × Age + 0.63 × Ln(WBC)²] 1.