Maiwall et al reported a PIRO (predisposition, injury, response, organ failure) model for acute kidney injury in a patient with acute-on-chronic liver failure (ACLF). The authors are from multiple institutions from around the world.
Patient selection: acute-on-chronic liver failure
Outcome: acute kidney injury (AKI) - one or more of the following: rise in serum creatinine > 0.3 mg/dL within 48 hours; >= 50% increase from admission value at day 7; initiation of renal replacement therapy
The authors developed both a nomogram and reported a logistic regression formula.
Parameters:
(1) serum BUN in mg/dL
(2) serum creatinine in mg/dL
(3) circulatory failure
(4) nephrotoxicity (as injury)
(5) systemic inflammatory response syndrome (SIRS, as response)
(6) serum potassium in mmol/L
(7) serum total bilirubin in mg/dL
points for BUN =
= MIN(100,0.2857*(BUN))
Parameter
|
Finding
|
Points
|
serum creatinine
|
< 2 mg/dL
|
0
|
|
>= 2 mg/dL
|
52
|
circulatory failure
|
no
|
0
|
|
yes
|
14.8
|
nephrotoxicity
|
no
|
0
|
|
yes
|
27.2
|
SIRS
|
no
|
0
|
|
yes
|
8
|
serum potassium
|
< 3 mmol/L
|
0
|
|
3 to 4.99 mmol/L
|
11
|
|
>= 5 mmol/L
|
17.3
|
serum total bilirubin
|
< 12 mg/dL
|
0
|
|
12 to 29.9 mg/dL
|
4.4
|
|
>= 30 mg/dL
|
10.5
|
total score =
= SUM(points for all 7 parameters)
Interpretation:
• minimum score: 0
• maximum score: 230
• The higher the score the greater the risk of acute kidney injury.
X =
= (0.087001 * (score)) - 5.4643
probability of AKI =
= 1 / (1 + EXP((-1) * X))
Performance:
• The area under the ROC curve in the development set was 0.95.