Further work on the Mayo Risk Score in patients with primary sclerosing cholangitis resulted in the Current Mayo Natural History Model. The risk score is plotted over time. An upward trend in the risk score is seen in the terminal phases of primary sclerosing cholangitis and can help in making therapeutic decisions such as the timing of liver transplantation. The score may obviate the need for a liver biopsy.

Parameters in score:

(1) age

(2) presence or absence of esophageal variceal bleeding

(3) serum total bilirubin

(4) serum albumin

(5) serum AST


Mayo risk score (R) =

= (0.0295 * (age in years)) + (0.5373 * LN(total bilirubin in mg/dL)) – (0.8389 * (serum albumin in g/dL)) + (0.5380 * LN(AST in IU/L) + (1.2426 * (points for variceal bleeding))



• LN indicates the natural logarithm

• Most references to the score round the coefficients to 2 decimal places.

• points for variceal bleeding: 0 if none, 1 if present



• Each unit increase in the Mayo risk score is associated with a 2.5-fold increase in the risk of death.

• The score shows very slight upward slope over time in stable patients, but during the terminal phase it shows an acceleration in progression.


Mayo Risk Score

Risk Group

<= 0


> 0 and < 2


>= 2


(page 1644, Kim, 1999)

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