MAGENT

Child-Pugh score: how the points are calculated

The Child-Pugh score (also called the Child-Turcotte-Pugh or CTP score) is a point score for a person with cirrhosis. It gives 1, 2 or 3 points each for five items: bilirubin, albumin, INR, encephalopathy and ascites. The total runs from 5 to 15.

Not a medical device. Not a diagnosis or dosing recommendation.

Use this calculator via API

What is the Child-Pugh score?

Magent's record cites the 1973 paper by Pugh, Murray-Lyon, Dawson, Pietroni and Williams in the British Journal of Surgery. Magent's record says that paper scored clotting as prothrombin time (PT) prolonged by 1–4, 4–6 or more than 6 seconds. Magent's calculator uses INR instead, as the record's contemporary laboratory substitute.

This page explains the arithmetic. The class letters appear only in the exact expression the calculator uses, below; this page doesn't say what a score or class means for a particular person.

The Child-Pugh formula

Child-Pugh = bilirubin points (1–3)
           + albumin points (1–3)
           + INR points (1–3)
           + encephalopathy points (1–3)
           + ascites points (1–3)
range = 5 to 15

Exact expression the calculator uses:

Child-Pugh = bilirubin + albumin + INR + encephalopathy + ascites; each 1-3; class A 5-6, B 7-9, C 10-15; max 15

What each part means

ItemWhat earns pointsPoints
Bilirubin (mg/dL)Under 2.01
2.0 to 3.02
Over 3.03
Albumin (g/dL)Over 3.51
2.8 to 3.52
Under 2.83
INRUnder 1.701
1.70 to 2.302
Over 2.303
EncephalopathyNone1
Grade 1–22
Grade 3–43
AscitesNone1
Slight2
Moderate3

How the score works

  1. Bilirubin. Under 2.0 mg/dL is 1, 2.0 to 3.0 is 2, and over 3.0 is 3. A value in µmol/L is divided by 17.1 first.
  2. Albumin. Over 3.5 g/dL is 1, 2.8 to 3.5 is 2, and under 2.8 is 3. A value in g/L is divided by 10 first.
  3. INR. Under 1.70 is 1, 1.70 to 2.30 is 2, and over 2.30 is 3.
  4. Encephalopathy. None is 1, grade 1–2 is 2, grade 3–4 is 3.
  5. Ascites. None is 1, slight is 2, moderate is 3.
  6. Add them up. Every item scores at least 1, so the lowest total is 5 and the highest is 15.

Inputs come from the user

The record says the person using the calculator assigns the encephalopathy grade and the amount of ascites. Magent's calculator doesn't examine anyone. It takes bilirubin from 0.1 to 40 mg/dL (or 2 to 684 µmol/L), albumin from 1 to 6 g/dL (or 10 to 60 g/L), and INR from 0.8 to 10. It returns the total, the converted values it used, and a line for each item.

Worked example

This is the worked example in Magent's record for the calculator.

Example 1: every item at 1 point

  1. Bilirubin 1.0 mg/dL → 1. Albumin 4.0 g/dL → 1. INR 1.2 → 1.
  2. No encephalopathy → 1. No ascites → 1.
  3. Score = 5, the lowest possible total.

Values at the boundaries

All are Magent's expected values for the calculator.

  • Bilirubin 2.0, albumin 3.0 and INR 2.0, with no encephalopathy or ascites → 8.
  • Bilirubin 3.0, albumin 2.8 and INR 2.30 (each at the edge of the middle range) → 8.
  • Bilirubin 4.0, albumin 2.0, INR 3.0, grade 3–4 encephalopathy and moderate ascites → 15.
  • Bilirubin 17.1 µmol/L converts to 1.0 mg/dL; albumin 40 g/L converts to 4.0 g/dL.

History of the Child-Pugh score

Magent's record cites Pugh RNH, Murray-Lyon IM, Dawson JL, Pietroni MC and Williams R, Transection of the oesophagus for bleeding oesophageal varices, British Journal of Surgery, 1973 (volume 60, issue 8, pages 646–649).

When it's used

Magent's record describes the calculator as a cirrhosis severity score built from three blood tests and two clinical grades.

Where it's used

The inputs are routine liver blood tests and two findings that the person using the calculator grades.

Who uses it

The person using the calculator enters the lab values and assigns the encephalopathy and ascites grades. The calculator does the unit conversions and the adding.

Limits of the calculation

  • It adds up points. It isn't a transplant listing protocol and it isn't a substitute for MELD-Na.
  • It uses INR where the 1973 paper used prothrombin time in seconds.
  • Encephalopathy and ascites are grades the user assigns.
  • This page doesn't say what a score or class means or what to do with it.

Clinical decisions belong to a qualified clinician who knows the patient.

  • MELD-Na is a separate liver score. Magent's Child-Pugh record says it isn't a substitute for MELD-Na.
  • Maddrey discriminant function is a separate liver calculation with its own inputs.
  • FIB-4 is a separate liver calculation with its own inputs.

Glossary

  • Cirrhosis: scarring of the liver.
  • Bilirubin: a yellow pigment the liver clears from the blood.
  • Albumin: a protein made by the liver.
  • INR (international normalized ratio): a standardized way of reporting how long blood takes to clot.
  • Encephalopathy: confusion or drowsiness caused by liver disease.
  • Ascites: fluid in the abdomen.

Common mistakes

  • Starting each item at zero. Every item scores at least 1, so the lowest total is 5.
  • Entering bilirubin in µmol/L in the mg/dL field. Use the µmol/L field; the calculator divides by 17.1.
  • Scoring an INR of 2.30 as 3. 2.30 is still in the middle range; the 3-point range starts above it.
  • Entering prothrombin time in seconds. The calculator takes INR.

Source

Pugh RNH, Murray-Lyon IM, Dawson JL, Pietroni MC, Williams R. Transection of the oesophagus for bleeding oesophageal varices. Br J Surg. 1973;60(8):646-649. DOI: 10.1002/bjs.1800600817

Frequently asked questions

How do you calculate the Child-Pugh score?

Give 1, 2 or 3 points each for bilirubin, albumin, INR, encephalopathy and ascites, then add them. The total is 5 to 15.

What does a Child-Pugh score of 8 mean?

This page doesn't give an outcome by score or class. It adds up the points; what a score means depends on the person and the clinical context.

Why is the lowest Child-Pugh score 5?

Each of the five items scores at least 1.

Does the calculator use PT or INR?

INR. Magent's record says the 1973 paper used prothrombin time prolonged by 1–4, 4–6 or more than 6 seconds; Magent's calculator uses INR under 1.70, 1.70 to 2.30, or over 2.30 instead.

What is a CTP score?

CTP stands for Child-Turcotte-Pugh, another name for the Child-Pugh score.