How is the INR value used to assign the coagulation point in the Child‑Pugh score for classifying a child's liver disease?

Child-Pugh Classification Using INR

The INR is scored in the Child-Pugh classification as follows: INR <1.7 = 1 point, INR 1.7-2.2 = 2 points, and INR >2.2 = 3 points. 1, 2

How the Child-Pugh Score Works

The Child-Pugh score assesses the severity of chronic liver disease (primarily cirrhosis) using five clinical and laboratory variables, each scored from 1 to 3 points:

The Five Variables:

1. INR (International Normalized Ratio)

   • <1.7 = 1 point
   • 1.7-2.2 = 2 points

   • 2.2 = 3 points

2. Total Bilirubin

   • <2 mg/dL = 1 point
   • 2-3 mg/dL = 2 points

   • 3 mg/dL = 3 points

3. Albumin

   • 3.5 g/dL = 1 point

   • 2.8-3.5 g/dL = 2 points
   • <2.8 g/dL = 3 points

4. Ascites

   • None = 1 point
   • Slight/mild (diuretic-responsive) = 2 points
   • Moderate/tense (diuretic-refractory) = 3 points

5. Hepatic Encephalopathy

   • None = 1 point
   • Grade 1-2 (or precipitant-induced) = 2 points
   • Grade 3-4 (chronic) = 3 points

Classification by Total Score

The total points (5-15) determine the Child-Pugh class:

• Child-Pugh A (mild): 5-6 points
• Child-Pugh B (moderate): 7-9 points
• Child-Pugh C (severe): 10-15 points 1, 3

Clinical Significance of INR in Liver Disease

The INR reflects synthetic liver function and coagulopathy severity. Higher INR values indicate more severe hepatic dysfunction and correlate with increased bleeding risk and mortality. 4, 5

Important Caveats:

• INR should NOT be used to gauge bleeding risk in cirrhosis patients 6. The INR was designed for monitoring warfarin therapy, not for assessing hemostasis in liver disease, where both pro- and anticoagulant factors are reduced.

• In pediatric populations with chronic liver disease, INR remains a robust independent predictor of disease severity (OR: 86.8 for Child-Pugh B vs A; OR: 82.4 for C vs A) 4

• The INR component of the Child-Pugh score correlates with advanced esophageal varices grades (III and IV) in cirrhotic patients 5

Practical Application

When calculating the Child-Pugh score, obtain the INR from standard coagulation testing, then assign the appropriate point value based on the thresholds above. Sum all five component scores to determine the final classification, which guides prognosis, treatment decisions (including anticoagulation choices in atrial fibrillation), and liver transplant prioritization 1, 7, 8.