Serum factor V and arterial lactate levels predict graft survival in liver transplant recipients with aminotransferase above five thousand

Abstract

BACKGROUND

Liver transplantation (LT) is the preferred treatment for end-stage liver diseases. Early allograft failure (EAF) can result in death or retransplantation. One of the key factors predicting EAF is the degree of graft injury, which is typically assessed by elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Aminotransferase levels exceeding 5000 U/L within 48 hours of LT are indicative of poor short-term graft survival.

AIM

To investigate outcomes in liver transplant recipients with peak aminotransferase levels exceeding 5000 U/L and to identify predictors of EAF.

METHODS

Adult patients who underwent LT from a deceased (brain-dead) donor between 2011 and 2024 at Hospital de Clínicas de Porto Alegre were screened. Patients with peak AST or ALT levels > 5000 U/L post-LT were included, excluding those with vascular thrombosis. EAF was defined as death or re-transplantation within 90 days. A receiver operating characteristic curve were generated for each EAF predictor to determine the area under the curve (AUC). Sensitivity, specificity, negative predictive value, and positive predictive value were calculated for each predictor’s best cutoff, as defined by the Youden Index. Survival curves were plotted using the Kaplan-Meier method.

RESULTS

Between 2011 and 2024, 341 patients underwent LT. Of these, 29 (8.5%) patients had AST and/or ALT levels exceeding 5000 U/L within the first 48 hours post-LT. Four patients were excluded due to vascular thrombosis, resulting in a study cohort of 25 patients. EAF were also observed in 11 patients. One-year and five-year graft survival rates were 51.7% and 42.6%, respectively. For patients without EAF, one-year and five-year graft survivals were 92.3% and 76.2%, respectively. The key predictors of EAF included serum factor V and arterial lactate levels on postoperative day (POD) 1, with AUCs of 0.936 and 0.919, respectively. The optimal cutoff for EAF prediction were 26.2% for serum factor V and 9 mmol/L for arterial lactate.

CONCLUSION

Aminotransferase levels > 5000 U/L were associated with high EAF risk. However, favorable graft function indicators on POD 1 were associated with long-term survival comparable to that of general LT recipients. Serum factor V and arterial lactate levels emerged as valuable prognostic markers.

Keywords: Aminotransferase; Liver transplantation; Early allograft failure; Factor V; Lactate

Core Tip: Among 341 liver transplant recipients, 25 had an aminotransferase level > 5000 U/L. Early allograft failure (death or re-transplantation within 90 days) occurred in 11 patients. One-year and five-year graft survival rates were 51.7% and 42.6%, respectively. However, approximately 50% of these patients withstood initial graft injury and had a satisfactory long-term prognosis. Therefore, early identification of patients who will recover graft function or undergo graft loss is paramount. Serum factor V and arterial lactate levels can aid in deciding whether to relist patients to retransplantation early in the postoperative period.