Abstract and Introduction
Abstract
Background Acute liver failure (ALF) is a clinical syndrome with very high mortality estimates ranging between 60% and 80%.
Aim To investigate the explicitness and extent of variability in the used ALF definitions in the ALF prognostic literature.
Methods All studies that pertain to the prognosis of patients with ALF were electronically searched in MEDLINE (1950–2012) and EMBASE (1950–2012). Identified titles and abstracts were independently screened by three reviewers to determine eligibility for additional review. We included English articles that reported original data from clinical trials or observational studies on ALF patients.
Results A total of 103 studies were included. Of these studies 87 used 41 different ALF definitions and the remaining 16 studies did not report any explicit ALF definition. Four components underlying ALF definitions accounted for the differences: presence and/or grading of hepatic encephalopathy (HE); the interval between onset of disease and occurrence of HE; presence of coagulopathy and pre-existing liver disease.
Conclusions The diversity in acute liver failure definitions hinders comparability and quantitative analysis among studies. There is room for improvement in the reporting of acute liver failure definitions in prognostic studies. The result of this review may be useful as a starting point to create a uniform acute liver failure definition.
Introduction
Acute liver failure (ALF) is a clinical syndrome with reported mortality estimates ranging between 60 and 80% depending on the cause and the expertise of the clinical department to which the patient is referred. The diagnosis of ALF determines estimates of its prevalence, treatment such as liver transplantation, and the performance of prognostic indicators of (poor) outcome as well as commonly used prognostic models, such as MELD score, King's College Criteria and Clichy criteria. Quantitative synthesis of evidence on ALF and consistency in care provision plans require uniformity of definition of ALF. The purpose of this review is to investigate the extent of variability and explicitness of the used ALF definitions in studies focusing on evaluating indicators of ALF outcome in an extensive survey of literature.