Prognostic Formula for Patient with Acute Liver Failure

 

Parameters:

(1) serum total bilirubin in mg/dL

(2) liver volume based on computer tomography in mL

(3) liver volume based on body surface area (Urata et al, see 11.17.04)

 

Z =

= (4.5734 * (liver volume by CT scan) / (liver volume by BSA)) - (0.15234 * (total serum bilirubin)) - 2.6213

 

Interpretation:

• A Z score < 0 predicts a poor prognosis.

 

Performance:

• The sensitivity is 94% and specificity 77%.

• The area under the ROC curve is 0.88.

• The PPV is 84% and NPV 91%.

 

The authors also developed a second equation wit a similar area under the ROC curve:

 

score =

= (5.1912 * (liver volume by CT scan) / (liver volume by BSA)) - (0.07967 * (total serum bilirubin)) + (0.0002824 * (ALT in IU/L)) - (0.04547 * (number of days before hepatic encephalopathy)) - 3.7869