Early Allograft Dysfunction After Live Donor Liver Transplantation: It's Time to Redefine?

BACKGROUND

An ideal definition of early allograft dysfunction (EAD) after live donor liver transplantation (LDLT) remains elusive. The aim of the present study was to compare the diagnostic accuracies of existing EAD definitions, identify the predictors of early graft loss due to EAD, and formulate a new definition, estimating EAD-related mortality in LDLT recipients.

METHODS

Consecutive adult patients undergoing elective LDLT were analyzed. Patients with technical (vascular, biliary) complications and biopsy-proven rejections were excluded.

RESULTS

There were 19 deaths due to EAD of a total of 304 patients. On applying the existing definitions of EAD, we revealed their limitations of being either too broad with low specificity or too restrictive with low sensitivity in patients with LDLT. A new definition of EAD-LDLT (total bilirubin >10 mg/dL, international normalized ratio [INR] > 1.6 and serum urea >100 mg/dL, for five consecutive days after day 7) was derived after doing a multivariate analysis. In receiver operator characteristics analysis, an AUC for EAD-LDLT was 0.86. The calibration and internal cross-validation of the new model confirmed its predictability.

CONCLUSION

The new model of EAD-LDLT, based on total bilirubin >10 mg/dL, INR >1.6 and serum urea >100 mg/dL, for five consecutive days after day 7, has a better predictive value for mortality due to EAD in LDLT recipients.

Nonalcoholic Fatty Liver in Lean Individuals: Clinicobiochemical Correlates of Histopathology in 157 Liver Biopsies from Healthy Liver Donors

BACKGROUND

Generally diagnosis of non-alcoholic fatty disease is made on imaging, however, mild steatosis is difficult to diagnose on imaging. Liver biopsy is the procedure of choice but is not carried out as it is an invasive procedure. We describe our experience of 157 liver biopsies in living liver donors with normal body mass index (BMI) <23 kg/M² (lean).

MATERIALS AND METHODS

The study was conducted at a tertiary care center in north India. Data of lean living donors who underwent a liver biopsy before donation were analyzed. Data are presented as percentage, mean, or median (25-75 interquartile range).

RESULTS

Of 718 donors who had a liver biopsy before donation, 157 (21.8%) donors were lean (BMI < 23 kg/M²). Seventy-eight percent of lean donors had no or only one metabolic risk factor. Fifty-three (33.7%) of lean donors had nonalcoholic fatty liver (NAFL) in liver biopsy. When donors with NAFL were compared to donors with normal histology, donors with NAFL had significantly higher aspartate transaminase (26.6 ± 7.5 versus 23.7 ± 5.4, p = 0.007), alanine transaminase (33.4 ± 11.7 versus 27.8 ± 10.7, p = 0.003), and gamma glutamyl transpeptidase [25 (16-40.5) versus 18 (14-23), p = 0.003]. Only triglycerides (TGs) were statistically different among metabolic factors in lean NAFL and normal histology groups, 97 (70-161) versus 86 (62.5-114.7), p = 0.043. A total of 30% donors in the lean NAFL group had TGs >150 mg/dl as compared with 12.5% in the normal histology group, p = 0.009. Other metabolic risk factors were not statistically different.

CONCLUSION

One third of lean donors had NAFL. Among all metabolic risk factors, only higher TGs levels showed a significant association with NAFL.

Poor Performance Status Predicts Mortality After Living Donor Liver Transplantation

BACKGROUND/AIMS

Performance status may adversely affect living donor liver transplantation (LDLT) outcomes. We present our data regarding performance status and posttransplantation survival in a large LDLT cohort.

METHODS

Patients with ABO incompatibility, of pediatric age, with acute liver failure, with hepatocellular carcinoma, and/or who had incomplete data were excluded. Two hundred sixty adults who had decompensated cirrhosis and underwent LDLT from January 2016 to March 2018 were included. Performance status was assessed by Karnofsky Performance Score (KPS). The data are depicted as number, mean (SD), or median (25-75 interquartile range [IQR]).

RESULTS

The cohort included 232 males and 28 females, aged 48.3 ± 9.8 years. Etiology of liver disease was hepatitis B in 33, hepatitis C in 19, alcohol related in 120, nonalcoholic steatohepatitis/cryptogenic in 68, and other etiologies in 20 patients. The mean Child's score was 9.6 ± 1.7, Model for End-Stage Liver Disease (MELD) score was 18.0 ± 5.8, and donor age was 33.4 ± 9.9 years. Forty-one recipients died at median follow-up of 11 months. The KPS was 100 in 6 (no deaths), 90 in 53 (2 deaths), 80 in 93 (12 deaths), 70 in 69 (14 deaths), 60 in 26 (8 deaths), and 50 in 13 (5 deaths) (P = 0.003). The area under the receiver operating characteristic curve of KPS to predict mortality was 0.698 (P = 0.000, 95% confidence interval [CI] = 0.616-0.780), and the best sensitivity (63%) and specificity (67%) were achieved at KPS ≤70. The survivors and nonsurvivors had a significant difference with respect to KPS (77.6 ± 10.9 versus 69.5 ± 10.9, P 0.000), age of the patient (47.8 ± 9.4 versus 51.1 ± 11.7; P = 0.047), postoperative infections (53.8% versus 85.3%, P = 0.001), and need of packed red cells transfusion. Multivariate analysis (Cox proportional-hazard) showed KPS (hazard ratio [HR] = 0.96, 95% CI = 0.93-0.99, P = 0.007), postoperative infections (HR = 2.3, 95% CI = 1.04-5.1, P = 0.038), and recipient age (HR = 1.03, 95% CI = 1.002-1.07, P = 0.039) as predictors of mortality.

CONCLUSION

Pretransplant performance status is one of the predictors of mortality after LDLT.

Living Donor Liver Transplantation Using Small-for-Size Grafts: Does Size Really Matter?

BACKGROUND

In living donor liver transplantation (LDLT), graft-to-recipient weight ratio (GRWR) > 0.8% is perceived as the critical graft size. This lower limit of GRWR (0.8%) has been challenged over the last decade owing to the surgical refinements, especially related to inflow and outflow modulation techniques. Our aim was to compare the recipient outcome in small-for-size (GRWR < 0.8) versus normal-sized grafts (GRWR > 0.8) and to determine the risk factors for mortality when small-for-size grafts (SFSG) were used.

METHODS

Data of 200 transplant recipients and their donors were analyzed over a period of two years. Routine practice of harvesting middle hepatic vein (MHV) or reconstructing anterior sectoral veins into neo-MHV was followed during LDLT. Outcomes were compared in terms of mortality, hospital stay, ICU stay, and occurrence of various complications such as functional small-for-size syndrome (F-SFSS), hepatic artery thrombosis (HAT), early allograft dysfunction (EAD), portal vein thrombosis (PVT), and postoperative sepsis. A multivariate analysis was also done to determine the risk factors for mortality in both the groups.

RESULTS

Recipient and donor characteristics, intraoperative variables, and demographical data were comparable in both the groups (GRWR < 0.8 and GRWR ≥ 0.8). Postoperative 90-day mortality (15.5% vs. 22.85%), mean ICU stay (10 vs. 10.32 days), and mean hospital stay (21.4 vs. 20.76 days) were statistically similar in the groups. There was no difference in postoperative outcomes such as occurrence of SFSS, HAT, PVT, EAD, or sepsis between the groups. Thrombosis of MHV/reconstructed MHV was a risk factor for mortality in grafts with GRWR < 0.8 but not in those with GRWR > 0.8.

CONCLUSION

Graft survival after LDLT using a small-for-size right lobe graft (GRWR < 0.8%) is as good as with normal grafts. However, patency of anterior sectoral outflow by MHV or reconstructed MHV is crucial to maintain graft function when SFSG are used.

Challenges and Outcome of Left-lobe Liver Transplants in Adult Living Donor Liver Transplants

Adult-to-adult living donor liver transplant (LDLT) frequently depend on using the right-lobes of the donor for obtaining adequate graft-to-recipient weight ratio (GRWR) of over 0.8% in the recipient. However, left-lobes remain an important option in adults, since the morbidity in the donor is considerably less with left donor hepatectomy when compared with right side liver resection. Further benefits of left-lobes in LDLT include more predictable anatomy of the left hepatic duct and left portal vein, which are usually long and single resulting in easier anastomosis in the recipient. Likewise, left-lobe grafts are easier to implant with an excellent venous outflow through the combined orifice of left and middle hepatic vein, as opposed to the complex hepatic vein reconstruction required in right-lobe grafts. However, left hepatic artery is often multiple unlike the right hepatic artery. The holy grail of left-lobe transplants is avoidance of small for size syndrome (SFSS) in the recipients. The strategies for overcoming SFSS currently depend on circumventing portal hyperperfusion in the graft. Measurement of portal pressure and modulating it if high, by splenic artery ligation, splenectomy, or hemiportocaval shunts are proving successful in avoiding SFSS. The future aim in adult LDLT should be to use the left-lobe as much as possible for the benefit of the donor at the same time avoiding SFSS even at very low GRWR for the benefit of the recipient.