Vibration Controlled Transient Elastography to Evaluate Steatosis in Candidate Living Donors for Liver Transplantation.

BACKGROUND: The ability of vibration controlled transient elastography (VCTE) to reliably exclude significant steatosis in living donor candidates could obviate the need for invasive liver biopsies, expedite the donor approval process, and reduce recipient wait time. We therefore aimed to determine whether VCTE controlled attenuation parameter (CAP) could be used to detect steatosis in potential living donors. METHODS: Living donor candidates who presented for evaluation between 2016 and 2019 underwent standard donor workup, VCTE, and liver biopsy if indicated. CAP scores were compared with MRI-Fat Fraction and, when available, histologic fat fraction from liver biopsy. Receiver operating characteristic curves were used to identify cutoffs with appropriate sensitivity and specificity for screening. Statistical analysis was conducted using R (version 3.6.0). RESULTS: Seventy-nine candidate living donors presented during the study period, of whom 71 were included in the final analysis and of whom 20 underwent liver biopsy. There was a positive correlation between MRI-Fat Fraction and CAP scores with an observed Spearman correlation coefficient of 0.424 ( P < 0.01). A CAP score of 271.5 dB/m or less was determined to have 89.8% sensitivity and 75% specificity for detecting <5% steatosis on MRI. The correlation between CAP and steatosis of available histologic samples had a Pearson correlation coefficient of 0.603 ( P = 0.005). A CAP cutoff of 276.0 dB/m demonstrated 66.7% sensitivity and 85.7% specificity for detecting <15% histopathologic steatosis and positive and negative predictive values of 71.5% and 82.7%, respectively. CONCLUSIONS: VCTE can be integrated into living donor evaluation to accurately screen for hepatic steatosis.

One-year morbidity after donor right hepatectomy.

Live donors are becoming an increasingly important source of donor organs in liver transplantation; however, long-term functional aspects of recovery from donor right hepatectomy are unknown. We analyzed donor outcomes at 1-year follow-up. We performed a single-center retrospective analysis of 70 right hepatectomy donors. Six-week and 1-year postoperative follow-up results were compared to preoperative baseline values. Ultrasonography was performed in all donors at 6 weeks and as clinically indicated. All donors were alive and well at the end of the study period. Of 66 right hepatic donors, only 22 (32%) were fully compliant with a 1-year follow-up visit. All those not compliant were contacted by phone. All complications except 1 (late finding of portal vein thrombosis) occurred in the perioperative (90-day) period. The incidence of bile leak was 4.3%, incisional hernia 20%, and autologous transfusion 1.0%. There were no aborted procedures. In those compliant with full 1-year follow-up, total bilirubin, aspartate aminotransferase, and alanine aminotransferase were normal in 97%. A total of 5 donors were noted to have persistence of asymptomatic thrombocytopenia beyond the perioperative period (90 days). These were investigated with Doppler sonography. Sonography was unremarkable in 3 of the 5, while 2 had abnormal findings: splenomegaly alone in 1, and splenomegaly with portal vein thrombosis in the other. Magnetic resonance angiography was performed in both, and the patient with portal vein thrombosis underwent endoscopy, which failed to reveal varices. Neither has clinical portal hypertension. Both remain asymptomatic albeit with stable thrombocytopenia. In conclusion, the majority of complications after donor right hepatectomy occur in the perioperative period. Later findings may include asymptomatic thrombocytopenia, with an incidence possibly as high as 23%, though the significance of this finding remains uncertain. Larger-scale studies are needed to confirm the true incidence and clinical significance of persistent thrombocytopenia in the donor hepatectomy population. Strategies to improve compliance with 1-year follow-up visits need to be developed.