Liver transplantation in acute liver failure: Dilemmas and challenges

Table 2 Problems with prognostic scoring systems in acute liver failure

Sr No	Issues	Remarks
1	All available prognostic scoring systems have limited accuracy	Error of both commission and omission can happen
2	Heterogeneity in the studies evaluating prognosis in ALF: Variations in the definitions of ALF, etiologies, & management protocol	The heterogeneity makes it difficult to compare the results between studies and draw a uniform conclusion
3	Survival rates of ALF patients on medical treatment have improved but models used are still the old ones	Reduced performance of old models (e.g., KCC) have been noted in the newer studies compared to the old ones
4	Many studies have considered and analyzed transplanted patients as ‘non-survivors’	This may falsely elevate the positive predictive value of a prognostic, increasing the risk of unnecessary LT in some patients
5	Lack of reproducibility and validation studies for many prognostic scores	A model cannot be implemented in the clinical practise without adequate validation studies
6	Dynamic models are better than models based on baseline parameters, but critical time at which decision should be made is not clear	A very late decision may results in loss of opportunity to transplant, and very early decision may lead to unnecessary LT
7	Many models have included non-ideal parameters, such as factor V, apoptotic markers, monocyte HLA, etc	These markers are not routinely available and their measurement involve additional investigations and cost
8	Some prognostic markers, such as serum bilirubin and INR, are subject to laboratory variations	This may cause error in selection of LT candidates
9	Inclusion of advanced HE in some prognostic models	HE is subjective markers, and advanced HE is usually a late feature of ALF
10	Inclusion of CE in prognostic models	CE is difficult to diagnosed clinically, and a clinically overt CE is usually a late feature

ALF: Acute liver failure; CE: Cerebral edema; HE: Hepatic encephalopathy; KCC: Kings college criteria; LT: Liver transplantation; INR: International normalized ratio; HLA: Human leukocyte antigen.