Poca et al reported a model for predicting mortality associated with spontaneous bacterial peritonitis in a patient with cirrhosis. This can help to identify a patient who may benefit from more aggressive management. The authors are from UniversitatAutonoma del Barcelona, Escola Universitariad'Infermeria EUI-Sant Pau and Hopitalde al Santa Creui Sant Pau in Barcelona.
Patient selection: cirrhosis with spontaneous bacterial peritonitis (SBT)
Parameters:
(1) serum urea in mmol/L
(2) white blood cell (blood leukocyte) count in 10^9/L
(3) mean arterial blood pressure in mm Hg
(4) Child-Pugh score, from 5 to 15
|
Parameter
|
Points
|
|
serum urea
|
0.12 * (urea)
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|
WBC count
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0.058 * WBC
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mean arterial pressure
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- 0.05 * MAP
|
|
Child-Pugh score
|
0.44 * (score)
|
where:
• The equation on page 633 gives the blood leukocyte coefficient as 61, which gives absurd results. The adjusted odds ratio is 1.06, with the natural logarithm 0.058.
value of X =
= SUM(points for all of the parameters) - 3.86
probability of mortality =
= 1 / (1 + EXP((-1) * X))
Performance:
• The area under the ROC curve is 0.85.
• A score >= 0.245 had a sensitivity of 0.85 and specificity of 0.75.
