Use of preprocurement biopsy in donation after circulatory death liver transplantation

Abnormal Liver Biopsies of Donor Grafts in Pediatric Liver Transplantation: How Do They Fare?

BACKGROUND Little is known about outcomes of pediatric patients transplanted using donor liver grafts with abnormal biopsy results. We assessed donor liver biopsy data to report characteristics and outcomes of abnormal livers transplanted in pediatric patients. MATERIAL AND METHODS We identified pediatric patients who received a liver transplant from a biopsied deceased donor between 2015 and 2022 using the national database UNOS Standard Transplant Analysis and Research files. Recipients were excluded if they received multi-organ transplants or were lost to follow-up. Livers with ≤5% macrosteatosis, no fibrosis, and no inflammation were classified as normal livers (NL). Allografts with >5% macrosteatosis, any fibrosis, or any inflammation were considered abnormal livers (AL). Donor and recipient demographic data and outcomes were examined. RESULTS Of the 3808 total pediatric liver transplants in the study period, there were 213 biopsied donor liver allografts transplanted into pediatric recipients. Of those, 114 were NL and 99 were AL. 35.4% (35/99) of the AL had >5% macrosteatosis with a mean of 7.6±11.4%, 64.6% (64/99) had any inflammation, and 18.2% (18/99) had any fibrosis. AL donors were significantly older than NL donors. AL recipients had higher PELD scores. There were no significant differences in length of stay, rejection rates and causes, or allograft survival between AL and NL. Multivariable analysis revealed that inflammation was independently associated with a significantly greater risk for graft failure. CONCLUSIONS Outcomes of abnormal livers are excellent. Inflammation was an independent risk factor for poor graft prognosis. Donor biopsies in pediatric liver transplantation can be a useful adjunct to assess outcomes.

Strategies to Improve the Utilization and Function of DCD Livers

Despite the increased usage of livers from donation after circulatory death (DCD) donors in the last decade, many patients remaining on the waitlist who need a liver transplant. Recent efforts have focused on maximizing the utilization and outcomes of these allografts using advances in machine perfusion technology and other perioperative strategies such as normothermic regional perfusion (NRP). In addition to the standard donor and recipient matching that is required with DCD donation, new data regarding the impact of graft steatosis, extensive European experience with NRP, and the increasing use of normothermic and hypothermic machine perfusion have shown immense potential in increasing DCD organ overall utilization and improved outcomes. These techniques, along with viability testing of extended criteria donors, have generated early promising data to consider the use of higher-risk donor organs and more widespread adoption of these techniques in the United States. This review explores the most recent international literature regarding strategies to optimize the utilization and outcomes of DCD liver allografts, including donor-recipient matching, perioperative strategies including NRP versus rapid controlled DCD recovery, viability assessment of discarded livers, and postoperative strategies including machine perfusion versus pharmacologic interventions.

Non-invasive evaluation of hepatic macrosteatosis in deceased donors

INTRODUCTION

Liver allocation changes have led to increased travel and expenditures, highlighting the need to efficiently identify marginal livers suitable for transplant. We evaluated the validity of existing non-invasive liver quality tests and a novel machine learning-based model at predicting deceased donor macrosteatosis >30%.

METHODS

We compared previously-validated non-invasive tests and a novel machine learning-based model to biopsies in predicting macrosteatosis >30%. We also tested them in populations enriched for macrosteatosis.

RESULTS

The Hepatic Steatosis Index area-under-the-curve (AUC) was 0.56. At the threshold identified by Youden's J statistic, sensitivity, specificity, positive, and negative predictive values were 49.6%, 58.9%, 14.0%, and 89.7%. Other tests demonstrated comparable results. Machine learning produced the highest AUC (0.71). Even in populations enriched for macrosteatosis, no test was sufficiently predictive.

CONCLUSION

Commonly used clinical scoring systems and a novel machine learning-based model were not clinically useful, highlighting the importance of pre-procurement biopsies to facilitate allocation.

DCD Hepatitis C Virus-positive Donor Livers Can Achieve Favorable Outcomes With Liver Transplantation and Are Underutilized

BACKGROUND

Hepatitis C virus (HCV)-positive donors (antibody-positive [Ab + ] or nucleic acid test positive [NAT + ] donors) have been underutilized. The aim of this study was to evaluate the utilization of livers from HCV-positive with donation after circulatory death (DCD) and to assess outcomes in recipients of these grafts.

METHODS

Data between 2015 and 2019 were obtained from the United Network for Organ Sharing database. The utilization rates and graft survival among 8455 DCD liver and nonliver donors and 2278 adult DCD liver transplantation (LT) recipients were reviewed on the basis of donor HCV Ab/NAT status.

RESULTS

The utilization of Ab + /NAT - donors <40 y and Ab + /NAT + donors ≥40 y was low than utilization of HCV-negative donors ( P  < 0.001). Multivariate analysis identified HCV status (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.06-2.48 in Ab + /NAT - , and OR, 1.49; 95% CI, 1.09-2.05 in Ab + /NAT + ) as an independent predictor of nonutilization of liver grafts. The rate of significant liver fibrosis was comparable in Ab + /NAT - (3.5%; P  = 0.84) but was higher in Ab + /NAT + (8.7%; P  = 0.03) than that in Ab - /NAT - donors. Kaplan-Meier survival curves demonstrated comparable 3-y patient survival in recipients of HCV-positive grafts compared with recipients of HCV-negative grafts ( P  = 0.63; 85.6% in Ab - /NAT - , 80.4% in Ab + /NAT - , and 88.7% in Ab + /NAT + ).

CONCLUSIONS

Patient and graft survival rates are similar between HCV-positive and HCV-negative DCD LT. However, HCV-positive donors are particularly underutilized for DCD LT.