A biochemical prognostic model of outcome in paracetamol-induced acute liver injury.
BACKGROUND
The aim of this study was to develop a prognostic model of outcome for patients with paracetamol induced acute liver injury based on admission parameters


METHODS
We used a cohort of 97 patients admitted to the Scottish Liver Transplant Unit between 1997 and 1998 to identify biochemical prognostic markers of outcome and thus create a prognostic model. Blood samples were taken on admission for analysis. The model was subsequently validated by testing it on a second cohort of 86 patients admitted between 1999 and 2000.


RESULTS
The following were identified as independent variables of poor prognosis (death/ transplant); phenylalanine, pyruvate, alanine, acetate, calcium, haemoglobin and lactate. A prognostic model was then constructed by stepwise forward logistic regression analysis: (400xPyruvate mmols/L)+(50xPhenylalanine (mmols/L)-(4 x Hemoglobin (g/dL). A value of <16 had an accuracy of 93% in predicting death correctly. When applied to the validation cohort this model had a positive predictive value of 91%, a negative predictive value of 94%, a sensitivity of 91%, and a specificity of 94%. On the same population overall, the positive and negative predictive value of the King's criteria were 94% and 93% respectively, whereas their sensitivity and specificity were 88% and 96% respectively.


CONCLUSIONS
Using admission characteristics our model is able to identify patients who die from paracetamol overdose fulminant hepatic failure as accurately as King's College criteria, but at a much earlier stage in their condition.
Dabos
Konstantinos John
KJ
Department of Hepatology, Royal Infirmary of Edinburgh and Ultra High Field NMR Centre, Department of Chemistry, University of Edinburgh, Edinburgh, UK. kostasophia@yahoo.com
Newsome
Philip Noel
PN
Parkinson
John Andrew
JA
Davidson
Janice Stewart
JS
Sadler
Ian Howard
IH
Plevris
John Nicholas
JN
Hayes
Peter Clive
PC
D000082:Acetaminophen / Q000633:toxicity*; D000328:Adult; D001774:Blood Chemical Analysis; D015331:Cohort Studies; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D008099:Liver / Q000187:drug effects / Q000473:pathology*; D016031:Liver Transplantation / Q000473:pathology* / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008706:Methemoglobin / Q000031:analogs & derivatives / Q000032:analysis; D020258:Neurotoxicity Syndromes / Q000453:epidemiology; D011379:Prognosis
D006454:Hemoglobins; C007169:cyanomethemoglobin; D000082:Acetaminophen; D008706:Methemoglobin