Impact of graft type on outcome in pediatric liver transplantation: a report From Studies of Pediatric Liver Transplantation (SPLIT)

Less is more: The use of single biodegradable stenting to treat biliary anastomotic strictures in pediatric liver transplantation

This study reports our experience of using biodegradable biliary stents (BBSs) for anastomotic biliary strictures (ABSs) in pediatric patients undergoing liver transplants. It involves the analysis of a retrospective data collection from January 2014 to January 2023, including all pediatric recipients of liver transplants in our center treated for ABSs with BBSs. In phase 1 (2014-2019), there was an initial percutaneous transhepatic cholangiography with anastomotic dilatation followed 2 weeks after a second percutaneous transhepatic cholangiography with BBS insertion. In phase 2 (2019-2023), the BBS was placed shortly after ABS dilatation, requiring only 1 percutaneous transhepatic cholangiography. All patients were followed up with routine tests and ultrasound. Forty-six ABSs were diagnosed in 43 pediatric recipients of liver transplants with a median of 6.7 months after liver transplantation (0.1-246.8 mo). Eight out of 46 ABSs (17.4%) treated with BBSs relapsed (median recurrence time: 6.5 mo; 1.6-17.0 mo). Four resolved with further BBS placement; only 4 needed surgical revision (8.7%) after a median follow-up time of 43.9 months (0.3-106.3). There were no differences in ABS recurrence rate, time between stent placement and recurrence, or the presence of cholangitis based on whether the BBS was deployed in 1 or 2 steps. Patients with end-to-end anastomosis had a higher ABS recurrence (OR 10.8; 1.4-81.3, p = 0.008) than those with bilioenteric anastomosis. The use of biodegradable stents could be a good option for treating ABSs in pediatric patients undergoing liver transplants, with our series showing a success rate of over 90% and an average follow-up of 43.9 months.

Expanding pediatric liver transplants: the role of split grafts, allocation policies, and machine perfusion

PURPOSE OF REVIEW

Pediatric liver transplant waitlist mortality remains disproportionately high, particularly among infants under one year old. Despite the success of split liver transplantation (SLT) in improving pediatric access to transplants, its utilization remains limited. This review examines barriers to SLT adoption, explores the impact of pediatric-focused allocation policies, and evaluates the potential of machine perfusion technology in expanding the pediatric donor pool.

RECENT FINDINGS

Studies have demonstrated that SLT outcomes are comparable to whole graft transplants when performed at experienced centers. However, logistical challenges, technical expertise, and policy limitations hinder its widespread adoption. Countries with pediatric-prioritized allocation and mandatory SLT policies, such as Italy and the United Kingdom, have significantly reduced pediatric waitlist mortality. Additionally, machine perfusion technology has emerged as a promising solution, allowing for ex vivo graft splitting and reducing ischemic injury, which may enhance graft utilization.

SUMMARY

A multifaceted approach is necessary to improve pediatric liver transplant outcomes, including stronger pediatric-first allocation policies, SLT training expansion, and integration of machine perfusion technologies. Implementing these strategies in the United States could significantly reduce pediatric waitlist mortality without negatively impacting adult transplant candidates.

Surgical Strategy for Pediatric Liver Tumors Involving the Hepatic Venous Confluence and the Inferior Vena Cava

BACKGROUND

Pediatric liver tumors presenting as centrally located masses with contact to or even invasion of all three hepatic veins (HVs) and the inferior vena cava (IVC) present significant surgical challenges. While liver transplantation may be indicated in truly unresectable tumors, extended liver resection with vascular reconstruction can be an organ-preserving alternative.

OBJECTIVE

This study aimed to present a reference center's strategy for children with liver tumors involving the hepatic venous confluence or the retrohepatic IVC who underwent extended liver resection with vascular reconstruction.

METHODS

All pediatric patients undergoing major hepatectomy with reconstruction of an HV or the IVC over a 10-year study period were included. Preoperative imaging, surgical techniques, and short- and long-term postoperative data were analyzed.

RESULTS

From a total of 125 pediatric major hepatectomies, 17 children (15 hepatoblastoma, two undifferentiated embryonal sarcoma) underwent liver resection with vascular reconstruction of an HV or the IVC. In nine cases an HV was reconstructed, and in eight children, a partial resection of the IVC was performed. Total vascular exclusion of the liver was applied in 16/17 cases. No 90-day postoperative mortality, no major postoperative complication, and no local relapse occurred; 16/17 patients are alive without relapse at a median follow-up of 44 months (range 19-111).

CONCLUSION

This is the largest single-center series to report major hepatectomies with HV or IVC reconstruction in children. In specialized centers, these complex procedures are associated with excellent outcomes. Successful tumor resection can be achieved in selected cases even in locally advanced tumor stages.

Clinical Outcomes of Percutaneous Transhepatic Biliary Drainage in Pediatric Patients following Liver Transplantation

Purpose

Cholestatic complications remain a primary cause of post-liver transplantation (LTX) morbidity in pediatric patients. Standard biliary access by endoscopic retrograde cholangioscopy may not be feasible due to modified biliary drainage. Percutaneous transhepatic biliary drainage (PTCD) may be performed alternatively. However, systematic data concerning safety and efficacy of PTCD in these patients are scarce.

Methods

In this retrospective study, procedural and safety characteristics of PTCD in pediatric patients following LTX were analyzed. We compared laboratory indicators of inflammation, cholestasis, and graft function before and at 6 and 12 months after the first PTCD insertion. Efficacy was analyzed by percentage of patients without cholangitis, need for surgical biliary re-intervention and re-transplantation during a follow-up period of 60 months.

Results

Over a decade, PTCD was attempted in a total of 15 patients, with technical success (93.3%) in 14 patients. Periprocedural complications, including bleeding (7.1%) and cholangitis (21.4%) were observed in patients. During follow-up, both MELD-score (baseline: 13 [8-15] vs. 12 months: 8 [7-8], p<0.001) and parameters of cholestasis (GGT: baseline: 286 [47-458] U/L vs. 12 months: 105 [26-147] U/L, p=0.024) decreased. Prior to PTCD, cholangitis (64.3%) and cholangiosepsis (21.4%) were common complications. In contrast, following PTCD, cholangitis occurred in only one patient (7.1%). Five patients (35.7%) needed surgical biliary re-intervention and two (14.3%) required re-transplantation.

Conclusion

PTCD in pediatric patients following LTX had an acceptable safety profile, demonstrating a biochemical improvement of both cholestasis and graft function and may prevent cholestatic complications, thus reducing the need for surgical re-intervention and re-transplantation.

Improved survival of pediatric deceased donor liver transplantation recipients after introduction of the pediatric prioritization system: Analysis of data from a Japanese national survey

BACKGROUND

In Japan, there has never been a national analysis of pediatric deceased donor liver transplantation (pDDLT) based on donor and recipient factors. We constructed a Japanese nationwide database and assessed outcomes of pDDLT focusing on the pediatric prioritization system introduced in 2018.

METHODS

We collected data on pDDLTs (<18 years) performed between 1999 and 2021 from the Japan Organ Transplant Network and Japanese Liver Transplantation Society, identified risk factors for graft survival and compared the characteristics and graft survival in pDDLTs conducted before and after the introduction of the pediatric prioritization system.

RESULTS

Overall, 112 cases of pDDLT were included, with a 1-year graft survival rate of 86.6%. Four poor prognostic factors were identified: recipient intensive care unit stay, model for end-stage liver disease/pediatric end-stage liver disease score, donor cause of death, and donor total bilirubin. After the introduction of the system, allografts from pediatric donors were more reliably allocated to pediatric recipients and the annual number of pDDLTs increased. The 1-year graft survival rate improved significantly as did pDDLT conditions indicated by the risk factors.

CONCLUSIONS

Under the revised allocation system, opportunities for pDDLT increased, resulting in favorable recipient and donor conditions and improved survival.

Primary Liver Transplant in Biliary Atresia: The Case for and Against

The role of liver transplantation as a primary procedure in biliary atresia has been argued over for at least 40 years, indeed since the coming of age of safe liver transplantation during the 1980s. Yet, it is not a common option in most series (usually ≤5%) and typically reserved for those with late presentations (arguably >100 days) with established cirrhosis. This review presents the pros and cons of primary liver transplant. The pros are based upon the observation that at best a Kasai portoenterostomy (KPE) is simply palliative in most, and at worse has no effect whatsoever on restoration of bile flow and is therefore pointless. Set against this are the cons: there is a dearth of prognostic tests (clinical, biochemical, or histological) at the time of presentation which may predict inevitable failure; the possibility of long-term native liver survival to adulthood in a proportion (albeit a minority); and the implied increased need for donor organs suitable for infants - a stressor for an already overstressed system. Improving results from KPE in terms of increasing the proportions clearing their jaundice and minimizing the effects of chronic liver fibrosis and cirrhosis would surely limit the siren calls for primary transplants but the key must be better discrimination at presentation with the use of biomarkers (circulatory or histological, individually or together) to enable better decision making.

Recipient-associated risk factors for post-liver transplantation biliary complications: A cohort study

INTRODUCTION

Biliary complications (BCs) are a well-documented post-liver transplantation concern with potential implications for patient survival. This study aims at identifying risk factors associated with the development of BCs in recipients after liver transplantation (LT) and exploring strategies for their management.

METHODS

We conducted a retrospective analysis of 1595 adult patients (age > 18 years) who underwent LT surgery between 2019 and 2021. The study assessed the incidence of BCs in this cohort.

RESULTS

Of 1595 patients, 178 (11.1%) experienced BCs, while 1417 (88.8%) did not exhibit any signs of such complications. Patients who developed BCs were found to have a significantly lower average age (p < 0.001) and longer cold ischemic times (p < 0.001) compared to those without BCs. Variables such as sex, body mass index (BMI), model for end-stage liver disease (MELD) score, primary diagnosis, type of anastomosis, hepatectomy technique, type of transplanted liver and mortality did not demonstrate statistically significant differences between the two groups (p > 0.05). Univariate logistic regression analysis revealed that a cold ischemic time exceeding 12 hours and duct-to-duct anastomosis were positive predictors for BC development (odds ratios of 6.23 [CI 4.29-9.02] and 1.47 [CI 0.94-2.30], respectively). Conversely, increasing age was associated with a protective effect against BC development, with an odds ratio of 0.64 (CI 0.46-0.89).

CONCLUSION

Our multi-variate analysis identified cold ischemia time (CIT) as the sole significant predictor of post-liver transplantation biliary complications. Additionally, this study observed that advancing patient age had a protective influence in this context. Notably, no significant disparities were detected between hepatectomy techniques and the etiology of liver disease types in the two study groups.

Post-liver transplant biliary complications

Biliary complications (BCs) are the most frequent complications following liver transplantation (LT). They are a major source of morbidity after LT. The incidence of BCs after LT is reported to range from 5% to 45%. The main post-LT biliary complications are strictures, biliary fistulas and bilomas, cholelithiasis, sphincter of Oddi dysfunction, hemobilia, and mucocele. Risk factors for biliary complications are diverse. In this article we seek to review the main types of biliary complications and modern approaches to their diagnosis and treatment.

Long-term outcomes of liver transplantation for biliary atresia and results of policy changes: over 20 years of follow-up experience

Objective

Biliary atresia (BA) patients develop chronic liver disease after the Kasai operation and are eventually indicated for liver transplantation (LT). The purposes of this study were to analyze long-term outcomes after LT and risk factors that affect complications to reduce graft failure.

Study design

Overall, 145 pediatric patients who underwent LT between June 1996 and June 2020 after a diagnosis of BA were included. We performed a retrospective analysis of medical records and evaluated patient and graft survival, cumulative incidence of complications, risk factors, and the results of policy changes.

Results

Patient and graft survival rates in over 20 years were 95.8% and 91.0%, respectively. Post-transplantation lymphoproliferative disease was frequently observed in the early period of immunosuppression within the first 1-2 years after LT. The incidence of cholangitis and rejection steadily increased over time. Weight-to-portal vein size was evaluated as a risk factor for cholangitis and bile duct strictures (OR = 12.82, p = 0.006 and OR = 16.54, p = 0.015, respectively). When evaluated using 2013 as a reference point, the split graft indication was expanded and the group that received LT after 2013 had a significantly lower survival over time compared with that of the group that received LT before 2013 (p = 0.006).

Conclusion

This study revealed time differences in prevalence of complications. The evaluation of weight-to-duct or vessel size is a more important factor in considering complications than the graft-to-recipient weight ratio. Survival outcomes may have been altered by a policy change that affects the donor type ratio in transplantation.

Technical Variant Liver Transplant Utilization for Pediatric Recipients: Equal Graft Survival to Whole Liver Transplants and Promotion of Timely Transplantation Only When Performed at High-volume Centers

BACKGROUND

Technical variant liver transplantation (TVLT) is a strategy to mitigate persistent pediatric waitlist mortality in the United States, although its implementation remains stagnant. This study investigated the relationship between TVLT utilization, transplant center volume, and graft survival.

METHODS

Pediatric liver transplant recipients from 2010 to 2020 (n = 5208) were analyzed using the Scientific Registry of Transplant Recipients database. Transplant centers were categorized according to the average number of pediatric liver transplants performed per year (high-volume, ≥5; low-volume, <5). Graft survival rates were compared using Kaplan-Meier curves and log-rank tests. Cox proportional hazards models were used to identify predictors of graft failure.

RESULTS

High-volume centers demonstrated equivalent whole liver transplant and TVLT graft survival ( P = 0.057) and significantly improved TVLT graft survival compared with low-volume centers ( P < 0.001). Transplantation at a low-volume center was significantly associated with graft failure (adjusted hazard ratio, 1.6; 95% confidence interval, 1.14-2.24; P = 0.007 in patients <12 y old and 1.8; 95% confidence interval, 1.13-2.87; P = 0.013 in patients ≥12 y old). A subset of high-volume centers with a significantly higher rate of TVLT use demonstrated a 23% reduction in waitlist mortality.

CONCLUSIONS

Prompt transplantation with increased TVLT utilization at high-volume centers may reduce pediatric waitlist mortality without compromising graft survival.

Biliary Leak after Pediatric Liver Transplantation Treated by Percutaneous Transhepatic Biliary Drainage-A Case Series

BACKGROUND

Biliary leaks are a severe complication after pediatric liver transplantation (pLT), and successful management is challenging.

OBJECTIVES

The aim of this case series was to assess the outcome of percutaneous transhepatic biliary drainage (PTBD) in children with bile leaks following pLT. The necessity of additional percutaneous bilioma drainage and laboratory changes during therapy and follow-up was documented.

MATERIAL AND METHODS

All children who underwent PTBD for biliary leak following pLT were included in this consecutive retrospective single-center study and analyzed regarding site of leak, management of additional bilioma, treatment response, and patient and transplant survival. The courses of inflammation, cholestasis parameters, and liver enzymes were retrospectively reviewed.

RESULTS

Ten children underwent PTBD treatment for biliary leak after pLT. Seven patients presented with leakage at the hepaticojejunostomy, two with leakage at the choledocho-choledochostomy and one with a bile leak because of an overlooked segmental bile duct. In terms of the mean, the PTBD treatment started 40.3 ± 31.7 days after pLT. The mean duration of PTBD treatment was 109.7 ± 103.6 days. Additional percutaneous bilioma drainage was required in eight cases. Bile leak treatment was successful in all cases, and no complications occurred. The patient and transplant survival rate was 100%. CRP serum level, leukocyte count, gamma-glutamyl transferase (GGT), and total and direct bilirubin level decreased significantly during treatment with a very strong effect size. Additionally, the gamma-glutamyl transferase level showed a statistically significant reduction during follow-up.

CONCLUSIONS

PTBD is a very successful strategy for bile leak therapy after pLT.

Utilization of Segmental Grafts Is Associated With Higher Transplant Rates in Pediatric Patients

INTRODUCTION

In July 2017, a policy to increase the use of segmental grafts (SGs) was implemented at our institution. The aim was to compare changes in waitlist activity after implementation of this policy.

METHODS

A single-center, retrospective study. Pediatric patients on the liver waiting list between January 2015 and December 2019 were screened. Patients were classified as receiving a liver transplant (LT) before (Period 1) or after (Period 2) policy changes. Primary end points were transplant rates and time to transplant.

RESULTS

Sixty five first LT performed on 65 patients were included. Twenty nine LT were performed during Period 1 and 36 during Period 2. More than half (55%) of LT in Period 2 were SG, compared to 10.3% in Period 1 (P < 0.001). Forty nine and 56 pediatric candidates on the waiting list accounted for 38.78 and 24.48 person-years during Period 1 and Period 2, respectively. Transplant rates per 100 person-years on the waiting list increased from 85.09 during Period 1 to 187.87 in Period 2 (Rate ratio: 2.20; P < 0.001). Median time to receive a LT decreased from 229 d in Period 1 to 75 d during Period 2 (P = 0.013). One-year patient survival rates were 96.6% in Period 1 and 95.7% in Period 2. One-year graft survival rates were 89.7% and 88% in Period 1 and Period 2, respectively.

CONCLUSIONS

A policy to increase the use of SG was associated with significantly higher transplant rates and lower waiting times. Implementation of this policy can be done successfully with no observed negative impact on patient and graft survival.

Comparative analysis of whole vs. split liver transplantation in infants

BACKGROUND

Liver transplantation (LT) in infants can be challenging due to their small size and small vasculature. Although both whole LT (WLT) and split LT (SLT) have been described in infants, the head-to-head comparison of these techniques in this population is sparse.

METHODS

We retrospectively analyzed the records of all patients with age ≤1 year at Indiana University between 2016 and 2022. All SLT were left lateral segment grafts split in situ.

RESULTS

A total of 24 infants were transplanted, with 11 SLT and 13 WLT. The median follow-up time was 52.1 months. Donor and recipient characteristics were comparable except for donor age (19 years vs. 2 years; p < .01) and weight (64 kg vs. 14.2 kg; p < .01). Early allograft dysfunction, primary nonfunction, and hepatic artery thrombosis developed more frequently in the WLT group. There were no biliary complications. There were two early deaths (2 and 4 days) in the WLT group. One-year graft survival (100% vs. 77%; p = .10) and patient survival (100% vs. 85%; p = .18) were numerically higher in the SLT group.

CONCLUSIONS

SLT with LLS offers a safe and viable option for liver transplantation in infants and is associated with a trend toward superior outcomes. SLT should be considered as a strategy to reduce waitlist times for infants in the absence of small, deceased donors for WLT.

Outcome of split liver transplantation vs living donor liver transplantation: A systematic review and meta-analysis

BACKGROUND

The outcomes of liver transplantation (LT) from different grafts have been studied individually and in combination, but the reports were conflicting with some researchers finding no difference in both short-term and long-term outcomes between the deceased donor split LT (DD-SLT) and living donor LT (LDLT).

AIM

To compare the outcomes of DD-SLT and LDLT we performed this systematic review and meta-analysis.

METHODS

This systematic review was performed in compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. The following databases were searched for articles comparing outcomes of DD-SLT and LDLT: PubMed; Google Scholar; Embase; Cochrane Central Register of Controlled Trials; the Cochrane Database of Systematic Reviews; and Reference Citation Analysis (https://www.referencecitationanalysis.com/). The search terms used were: "liver transplantation;" "liver transplant;" "split liver transplant;" "living donor liver transplant;" "partial liver transplant;" "partial liver graft;" "ex vivo splitting;" and "in vivo splitting."

RESULTS

Ten studies were included for the data synthesis and meta-analysis. There were a total of 4836 patients. The overall survival rate at 1 year, 3 years and 5 years was superior in patients that received LDLT compared to DD-SLT. At 1 year, the hazard ratios was 1.44 (95% confidence interval: 1.16-1.78; P = 0.001). The graft survival rate at 3 years and 5 years was superior in the LDLT group (3 year hazard ratio: 1.28; 95% confidence interval: 1.01-1.63; P = 0.04).

CONCLUSION

This meta-analysis showed that LDLT has better graft survival and overall survival when compared to DD-SLT.

Center use of technical variant grafts varies widely and impacts pediatric liver transplant waitlist and recipient outcomes in the United States

To assess the impact of technical variant grafts (TVGs) [including living donor (LD) and deceased donor split/partial grafts] on waitlist (WL) and transplant outcomes for pediatric liver transplant (LT) candidates, we performed a retrospective analysis of Organ Procurement and Transplantation Network (OPTN) data on first-time LT or liver-kidney pediatric candidates listed at centers that performed >10 LTs during the study period, 2004-2020. Center variance was plotted for LT volume, TVG usage, and survival. A composite center metric of TVG usage and WL mortality was developed to demonstrate the existing variation and potential for improvement. Sixty-four centers performed 7842 LTs; 657 children died on the WL. Proportions of WL mortality by center ranged from 0% to 31% and those of TVG usage from 0% to 76%. Higher TVG usage, from deceased donor or LD, independently or in combination, significantly correlated with lower WL mortality. In multivariable analyses, death from listing was significantly lower with increased center TVG usage (HR = 0.611, CI: 0.40-0.92) and LT volume (HR = 0.995, CI: 0.99-1.0). Recipients of LD transplants (HR = 0.637, CI: 0.51-0.79) had significantly increased survival from transplant compared with other graft types, and recipients of deceased donor TVGs (HR = 1.066, CI: 0.93-1.22) had statistically similar outcomes compared with whole graft recipients. Increased TVG utilization may decrease WL mortality in the US. Hence, policy and training to increase TVG usage, availability, and expertise are critical.

Comparing the Outcomes of Pediatric Liver Transplantation

BACKGROUND

Liver transplantation is a life-saving treatment for end-stage pediatric liver failure. We aimed to present the results of pediatric liver transplants performed in our center in the last 11 years (between 2012 and March 2022) in association with prognostic factors affecting survival.

METHODS

Demographic characteristics, etiologic reasons, previous operations (Kasai procedure), morbidity, mortality, survival, and bilio-vascular complication rates were determined, and outcomes were evaluated. In the postoperative period, the duration of mechanical ventilation and intensive care unit stay and surgical and other complications were evaluated. Graft and patient survival rates were determined, and univariate and multivariate factors affecting these rates were evaluated.

RESULTS

In the last 10 years, 229 pediatric liver transplantaion (Pe-LT)/1513 adult liver taransplantation (Ad-LT) (21.35%) were performed in our center. This ratio (Pe-LT/Ad-LT ratio) is 1741/15,886 (10.95%) for our country. A total of 229 liver transplants were performed in 214 pediatric patients. Retransplantation was performed in 15 patients (6.55%). Cadaveric liver transplantation was performed in 9 patients. Graft survival rates were 87%, 83%, 78%, 78%, 78%, and 78% at <30 days, 30 to 90 days, 91 to 364 days, 1 to 3 years, and >3 years, respectively. Patient survival rates for <30 days, 30 to 90 days, 91 to 364 days, 1 to 3 years, and >3 years were 91.5%, 85.7%, 82%, 81.5%, and 81.5%, respectively. Our 5-year survival rates in metabolic diseases and the acute fulminant failure group are 93.8% and 100%, respectively.

CONCLUSIONS

The fact that the 1- and 5-year survival rates are the same shows that when patients overcome biliary vascular and infectious problems, their survival is prolonged.

An appraisal of technical variant grafts compared to whole liver grafts in pediatric liver transplant recipients: Multicenter analysis from the SPLIT registry

BACKGROUND

Shortages of liver allografts for children awaiting transplantation have led to high LT waitlist mortality. Prior studies have shown that usage of TVG can reduce waiting time and waitlist mortality, but their use is not universal. We sought to compare patient and graft survival between WLG and TVG and to identify potential associated risk factors in a contemporary pediatric LT cohort.

METHODS

We performed a retrospective analysis of patient survival, graft survival, and biliary and vascular complications for LT recipients <18 years old entered into the Society of Pediatric Liver Transplantation prospective multicenter database.

RESULTS

Of 1839 LT recipients, 1029 received a WLG and 810 received a TVG from either a LD or a DD. There was no difference in patient survival or graft survival by graft type. Three-year patient survival and graft survival were 96%, 93%, and 96%, and 95%, 89%, and 92% for TVG-LD, TVG-DD, and WLG, respectively. Biliary complications were more frequent in TVG. Hepatic artery thrombosis was more frequent in WLG. Multivariate analysis revealed primary diagnosis was the only significant predictor of patient survival. Predictors for graft survival included time-dependent development of biliary and vascular complications.

CONCLUSIONS

There were no significant differences in patient and graft survival based on graft types in this North American multi-center pediatric cohort. Widespread routine use of TVG should be strongly encouraged to decrease mortality on the waitlist for pediatric LT candidates.

The impact of portal vein reconstruction on portal vein complications after pediatric living-donor liver transplantation with left lobe graft

BACKGROUND

This study aimed to determine whether the different methods of portal vein reconstruction have an impact on the occurrence of portal vein complications after pediatric living-donor liver transplantation with left lobe graft.

METHODS

A total of 567 recipients were eligible for enrollment in this study and were divided into the following 2 groups according to the type of portal vein reconstruction: group 1 underwent anastomosis of the left and right bifurcations of the recipient portal vein to the donor portal vein (type 1), whereas group 2 underwent anastomosis of the bevel formed by the main trunk and right branch of the recipient portal vein to the donor portal vein (type 2). Postoperative portal vein complications and recipient and graft survival rates were compared between the 2 groups before and after propensity score matching.

RESULTS

Portal vein complications occurred in 53 (9.3%) patients, including 46 recipients with portal vein stenosis and 7 with portal vein thrombosis. After propensity score matching, the incidence of portal vein stenosis in group 2 was lower than that in group 1 (P = .035). The first diagnosis time of portal vein stenosis in group 2 was later than that in group 1 (P = .033), and the incidence of early portal vein stenosis was lower than that in group 1 (P = .009). There were no statistically significant differences in the incidence of portal vein thrombosis and recipient and graft survival rates between the 2 groups.

CONCLUSIONS

Type 2 portal vein reconstruction appears to be a viable technique in pediatric living-donor liver transplantation with left lobe graft that can effectively reduce the incidence of portal vein stenosis.

Long-term outcomes of pediatric liver transplantation using organ donation after circulatory death: Comparison between full and reduced grafts

BACKGROUND

The shortage of donors' livers for pediatric recipients inspired the search for alternatives including donation after cardiac death (DCD).

METHODS

Retrospective review of pediatric liver transplant (PLT) using DCD grafts. Patients were divided into either FLG or RLG recipients. Pre-transplant recipient parameters, donor parameters, operative parameters, post-transplant recipient parameters, and outcomes were compared.

RESULTS

Overall, 14 PLTs from DCD donors between 2005 and 2018 were identified; 9 FLG and 5 RLG. All donors were Maastricht category III. Cold ischemia time was significantly longer in RLG (8.2 h vs. 6.2 h; p = .038). Recipients of FLG were significantly older (180 months vs. 7 months; p = .012) and waited significantly longer (168 days vs. 22 days; p = .012). Recipients of RLG tended to be sicker in the immediate pre-transplant period and this was reflected by the need for respiratory or renal support. There was no significant difference between groups regarding long-term complications. Three patients in each group survived more than 5 year post-transplant. One child was re-transplanted in the RLG due to portal vein thrombosis but failed to survive after re-transplant. One child from FLG also died from a non-graft-related cause.

CONCLUSIONS

Selected DCD grafts are an untapped source to widen the donor pool, especially for sick recipients. In absence of agreed criteria, graft and recipient selection for DCD grafts should be undertaken with caution.

Treatments and outcomes of intra-operative portal vein thrombosis in living-donor liver transplantation due to biliary atresia

BACKGROUND

Pediatric living-donor liver transplantation (LDLT) has become one of the most effective therapies for pediatric end-stage liver diseases. We aim to investigate the risk factors for intra-operative portal vein thrombosis (PVT) and the short- and long-term outcomes in children post LDLT.

METHODS

This was a retrospective analysis from 584 cases of biliary atresia (BA) patients who had undergone LDLT from January 2014 to December 2019 at our hospital. Patients were divided into PVT and non-PVT groups according to the occurrence of PVT during LDLT.

RESULTS

The median age of recipients at transplantation was 7.22 (quartiles, 6.03, 9.50) months, the incidence of intra-operative PVT was 5.31% (31/584). The independent risk factors for intra-operative PVT were the diameter of the recipient's PV not greater than 4 mm and a higher ratio of graft-to-recipient PV diameter. The cumulative survival rates of grafts and recipients were 93.5% and 93.5% in the PVT group, and 94.9% and 95.3% in the non-PVT group, respectively, without significant difference. The recovery of graft function was similar in recipients with or without interposed graft vessel (IGV). However, the incidence of PV stenosis was higher in recipients with IGV after LDLT.

CONCLUSION

Intra-operative PVT is a common complication in pediatric LDLT, but an excellent prognosis can be achieved by appropriate and individualized surgical treatment. We noted that intra-operative PVT did not affect the survival rates of grafts and recipients, but there was a higher incidence of PV complications after LDLT.

LEVEL OF EVIDENCE

Ⅲ.

Epidemiology and outcomes of surgical site infections among pediatric liver transplant recipients

INTRODUCTION

Surgical site infections (SSI) are a significant cause of morbidity in liver transplant recipients, and the current data in the pediatric population are limited. The goal of this study was to identify the incidence, classification, risk factors, and outcomes of SSIs among children undergoing liver transplantation (LT).

METHODS

A single-center, retrospective descriptive analysis was performed of patients age ≤18 years undergoing LT between September 2007 and April 2017. SSI identified within the first 30 days were analyzed. Primary endpoints included incidence, classification, risk factors, and outcomes associated with SSIs.

RESULTS

We included 86 patients, eight patients (9.3%) developed SSIs. Among segmental grafts (SG) recipients, 7/61 (11.4%) developed SSI. Among whole grafts recipients, 1/25 (4%) developed SSI. SSIs were associated with the presence of biliary complications (35% vs. 3%, p < .01; odds ratios 24, 95% CI: 3.41-487.37, p<.01). There were no differences in long term graft or patient survival associated with SSI. Patients who developed SSI were more likely to undergo reoperation (50% vs. 16.7%, p = .045) and had an increased total number of hospital days in the first 60 days post-transplant (30.5 vs. 12.5 days, p = .001).

CONCLUSIONS

SSIs after pediatric LT was less frequent than what has been previously reported in literature. SSIs were associated with the presence of biliary complications without an increase in mortality. SG had an increased rate of biliary complications without an association to SSIs but, considering its positive impact on organ shortage barriers, should not be a deterrent to the utilization of SGs.

The Role of Imaging in Portal Vein Thrombosis: From the Diagnosis to the Interventional Radiological Management

PURPOSE

To illustrate diagnostic and interventional imaging for the characterization and treatment of portal vein thrombosis (PVT).

INTRODUCTION

The broad spectrum of congenital and acquired PVT manifestations is illustrated, with a focus on the pediatric population; diagnostic and interventional imaging techniques are described.

DESCRIPTION

PVT frequently presents as an incidental finding at imaging in the screening for liver diseases or for other unrelated reasons. PVT can be classified based on: extension (intrahepatic, extrahepatic, involving the spleno-mesenteric tract, etc.); degree (partial or complete); onset (acute or chronic); and with or without cavernomatous transformation. This comprehensive review relies on the experience gained from a large series of congenital and acquired PVT in a referral center for pediatric and adult liver transplantation. Diagnostic and interventional imaging techniques are described, including: color-Doppler and contrast-enhanced Ultrasound; CT and MR angiography; retrograde portography; percutaneous transhepatic, transplenic, and transmesenteric portography; transjugular intrahepatic portosystemic shunt creation. Pre- and post-operative imaging assessment of the surgical meso-rex bypass is discussed. The description is enriched with an original series of pictorial imaging findings.

CONCLUSION

PVT is a clinical condition associated with significant morbidity and mortality. Diagnostic and interventional imaging plays a crucial role in both conservative and operative management.

Liver transplantation of partial grafts after ex situ splitting during hypothermic oxygenated perfusion-The HOPE-Split pilot study

Partial liver grafts from ex situ splitting are considered marginal due to prolonged static cold storage. The use of ex situ hypothermic oxygenated perfusion (HOPE) may offer a strategy to improve preservation of ex situ split grafts. In this single-center pilot study, we prospectively performed ex situ liver splitting during HOPE (HOPE-Split) for adult and pediatric partial grafts over a 1-year period (November 1, 2020 to December 1, 2021). The primary safety endpoint was based on the number of liver graft-related adverse events (LGRAEs) per recipient, including primary nonfunction, biliary complications, hepatic vascular complications, and early relaparotomies and was compared with consecutive single-center standard ex situ split transplantations (Static-Split) performed from 2018 to 2020. Secondary endpoints included preservation characteristics and early outcomes. Sixteen consecutive HOPE-Split liver transplantations (8 HOPE-Split procedures) were included and compared with 24 Static-Splits. All HOPE-Split grafts were successfully transplanted, and no graft loss nor recipient death was encountered during the median follow-up of 7.5 months (interquartile range, 5.5-12.5). Mean LGRAE per recipient was similar in both groups (0.31 ± 0.60 vs. 0.46 ± 0.83; p = 0.78) and split duration was not significantly increased for HOPE-Split (216 vs. 180 min; p = 0.45). HOPE-Split grafts underwent perfusion for a median of 125 min, which significantly shortened static cold storage (472 vs. 544 min; p = 0.001), whereas it prolonged total ex vivo preservation (595 vs. 544 min; p = 0.007) and reduced neutrophil infiltration on reperfusion biopsies (p = 0.04) compared with Static-Split. This clinical pilot study presents first feasibility and safety data for transplantation of partial liver grafts undergoing ex situ split during HOPE and suggests improved preservation compared with static ex situ splitting. These preliminary results will allow to set up large-scale trials on the use of machine perfusion in pediatric and split-liver transplantation.

Early thrombotic and hemorrhagic complications associated with a risk-adjusted postoperative anticoagulation protocol after pediatric liver transplantation

BACKGROUND

Systemic anticoagulation after pediatric liver transplantation (pLT) is believed to reduce the incidence of vascular thrombosis, but it may also cause an increase in hemorrhagic complications.

PROCEDURE

A 5-year retrospective review of pLT done at our institution was performed (2014-2018). The occurrence of early hemorrhagic and thrombotic complications was compared when using low-dose or high-dose anticoagulation after transplant (p < .05 considered significant).

RESULTS

Sixty-nine patients received 73 transplants during the study period. Median age at transplant was 2.3 years (40 days to 18.5 years). Low-dose anticoagulation was utilized in 71% cases. Additionally, six patients were converted from low-dose to high-dose anticoagulation because of a thrombotic event or concerns for suboptimal vascular inflow. Postoperative anticoagulation was discontinued in 18 occurrences due to bleeding (low dose 19%, high dose 47% vs. low dose to high dose 17%, p = .085). Surgical take back for bleeding occurred in 17 occasions (low dose 13.5%, high dose 53% vs. low dose to high dose 33%, p = .005). The overall incidence of hepatic artery thrombosis (HAT) and portal vein thrombosis were each 5.5%, respectively. While patient survival was not statistically different between groups, graft survival was significantly lower in the high-dose group (low dose 93%, high dose 73% vs. low dose to high dose 100%, p = .046). However, graft losses from HAT were similar between groups (low dose 2%, high dose 7% vs. low dose to high dose 0%, p = .56).

CONCLUSION

The use of a standardized risk-adjusted anticoagulation protocol after pLT is associated with a low occurrence of thrombotic and hemorrhagic complications. High-dose anticoagulation leads to more bleeding, but those risks outweigh the risks of possible graft loss.

Recipient Age Predicts 20-Year Survival in Pediatric Liver Transplant

INTRODUCTION

Pediatric liver transplant recipients have demonstrated excellent long-term survival. The purpose of this analysis is to investigate factors associated with 20-year survival to identify areas for improvement in patient care.

METHODS

Kaplan-Meier with log-rank test as well as univariate and multivariate logistic regression methods were used to retrospectively analyze 4,312 liver transplant recipients under the age of 18 between September 30, 1987 and March 9, 1998. Our primary endpoint was 20-year survival among one-year survival.

RESULTS

Logistic regression analysis identified recipient age as a significant risk factor, with recipients below 5 years old having a higher 20-year survival rate (p < 0.001). A preoperative primary diagnosis of a metabolic dysfunction was found to be protective compared to other diagnoses (OR 1.64, CI 1.20-2.25). African-American ethnicity (OR 0.71, CI 0.58-0.87) was also found to be a risk factor for mortality. Technical variant allografts (neither living donor nor cadaveric) were not associated with increased or decreased rates of 20-year survival.

CONCLUSIONS

Our analysis suggests that long-term survival is inversely correlated with recipient age following pediatric liver transplant. If validated with further studies, this conclusion may have profound implications on the timing of pediatric liver transplantation.

The survival rate of liver transplantation in children: a systematic review and meta-analysis

Liver transplantation is a life-saving treatment for children who are in liver failure. The survival rate index is used to assess the success rate of liver transplantation. The study aimed to assess the survival rate of liver transplantation in children. We searched 5 international databases in this study, including Medline/PubMed, ProQuest, Scopus, Web of Knowledge, and Google Scholar, for published articles by the end of 2020. Also, meta-regression analysis was performed based on the year of the study, and subgroup analysis was performed according to continents. A total of 425 titles were reviewed. Based on the results, 96 articles were entered in the meta-analysis. Established on the random-effect model, the survival rates of 1, 3, 5, and 10 years of transplantation were 86.62%, 77.74%, 73.95%, and 68.60%, respectively. Also, based on the meta-regression results, there was a relationship between the year of the study and the survival rate, as the study year gets more recent, the survival rate is increased. This study can provide documented and comprehensive evidence which can be the basis of many policies and decisions in various sectors of health development, including evaluating treatment options and health interventions in transplantation.

Predictors of portal vein complications after pediatric liver transplantation: A German center experience

BACKGROUND

Portal vein complications (PVCs) after pediatric liver transplantation (LT) are sometimes asymptomatic, especially in the early phase, and can threaten both the graft and patient's survival. Therefore, the purpose of this study is to analyze the risk factors for portal vein thrombosis (PVT) and portal vein stenosis (PVS) after pediatric LT.

METHODS

All pediatric patients (n = 115) who underwent primary LT at Regensburg University Hospital between January 2010 and April 2017 were included in this study. The pre-, intra-, and postoperative parameters of all patients were retrospectively reviewed and risk factors for both PVT and PVS were analyzed.

RESULTS

Of the 115 patients, living donor LT was performed on 57 (49.5%) patients, and biliary atresia was the primary diagnosis in 65 patients (56%). After pediatric LT, 9% of patients developed PVT, and 16.5% developed PVS. Patient weight ≤7 kg [odds ratio (OR) 9.35, 95% confidence interval (CI) 1.03-84.9, p = .04] and GRWR >3% (OR 15.4, 95% CI 1.98-129.5, p = .01) were the independent risk factors for the development of PVT and PVS, respectively upon multivariate analysis. The overall patient survival rates at 1, 3, and 5 years were 91%, 90%, and 89%, respectively, and there was no difference in patient survival among those with and without PVCs.

CONCLUSIONS

Pediatric patients with body weight <7 kg and/or receiving a graft with GRWR >3% may develop PVCs and so require certain surgical modifications, close follow-up, and prophylactic anticoagulant therapy following transplant.

Pediatric Liver Transplantation

Liver transplantation (LT) for children results in excellent short- and long-term patient and graft survival. LT is a lifesaving procedure in children with acute or chronic liver disease, hepatic tumors, and select genetic metabolic diseases in which it can significantly improve quality of life. In this article, the authors discuss the unique aspects of pediatric LT, including the indications, appropriate patient selection and evaluation, allocation of organs, transplant surgery including the use of variant grafts, posttransplant care including immunosuppression management, prognosis, and transition of care.

Portal vein complications and outcomes following pediatric liver transplantation: Data from the Society of Pediatric Liver Transplantation

Children who undergo liver transplantation are at risk for portal vein complications (PVCs) including thrombosis (PVT) and stenosis (PVS). Using multicenter data from the Society of Pediatric Liver Transplantation, we analyzed the prevalence, timing, and risk factors for PVC following a first liver transplantation, and assessed the potential impact of PVC on patient outcomes. Our cohort included 4278 patients, of whom 327 (7.6%) developed PVC. Multivariate analysis discovered several factors independently associated with PVC: younger recipient age, lower weight at time of transplantation, diagnosis of biliary atresia (BA), receiving a technical variant graft (TVG), warm ischemia time over 3 h, PVT in the recipient's pretransplantation native liver, and concurrent hepatic artery thrombosis (all p < 0.05). Subgroup analysis of those with BA found higher prevalence in patients transplanted at less than 2 years of age and those with TVGs. There was no difference in PVC prevalence among patients with BA with vs. without prior Kasai portoenterostomy. Most PVT (77.7%) presented within 90 days after transplantation. Patients with PVC had a higher risk of graft failure (23.9% vs. 8.3%; adjusted hazard ratio [HR], 3.08; p < 0.001) and a higher risk of death (16.4% vs. 8.9%; adjusted HR, 1.96; p = 0.01). Recurrence after retransplantation was similar to the overall prevalence in the cohort (8.2%). Our results recognize the common occurrence of PVC following pediatric liver transplantation, describe independently associated risk factors, and determine that patients with PVC have worse outcomes. Further studies are needed to improve PVC prevention, detection, and management strategies.

Recent Improvement in Survival Outcomes and Reappraisal of Prognostic Factors in Pediatric Living Donor Liver Transplantation

Living donor liver transplantation (LDLT) is a significant advancement for the treatment of children with end-stage liver disease given the shortage of deceased donors. The ultimate goal of pediatric LDLT is to achieve complete donor safety and zero recipient mortality. We conducted a retrospective, single-center assessment of the outcomes as well as the clinical factors that may influence graft and patient survival after primary LDLTs performed between 1994 and 2020. A Cox proportional hazards model was used for multivariate analyses. The trends for independent prognostic factors were analyzed according to the following treatment eras: 1, 1994 to 2002; 2, 2003 to 2011; and 3, 2012 to 2020. Primary LDLTs were performed on 287 children during the study period. Biliary atresia (BA; 52%), acute liver failure (ALF; 26%), and monogenic liver disease (11%) were the leading indications. There were 45 graft losses (16%) and 27 patient deaths (7%) in this population during the study period. During era 1 (n = 81), the cumulative survival rates at 1 and 5 years after LDLT were 90.1% and 81.5% for patients and 86.4% and 77.8% for grafts, respectively. During era 2 (n = 113), the corresponding rates were 92.9% and 92% for patients and 89.4% and 86.7% for grafts, respectively. During era 3 (n = 93), the corresponding rates were 100% and 98.6% for patients and 98.9% and 95.4% for grafts, respectively. In the multivariate analyses, primary diagnosis ALF, bloodstream infection, posttransplant lymphoproliferative disease, and chronic rejection were found to be negative prognostic indicators for patient survival. Based on generalized care guidelines and center-oriented experiences, comprehensive advances in appropriate donor selection, refinement of surgical techniques, and meticulous medical management may eventually realize a zero-mortality rate in pediatric LDLT.

Survival Benefit of Split-Liver Transplantation for Pediatric and Adult Candidates

Patient and graft survival are similar following whole-liver transplantations (WLTs) versus split-liver transplantations (SLTs) among pediatric and adult recipients, yet SLTs are rarely used. We sought to determine the survival benefit associated with accepting a splittable graft offer for SLT versus declining and waiting for a subsequent offer using 2010 to 2018 Scientific Registry of Transplant Recipients (SRTR) data on 928 pediatric and 1814 adult liver transplantation candidates who were ever offered a splittable graft. We compared eventual mortality, regardless of subsequent transplants, between those patients who accepted versus declined a split liver offer with adjustments for Pediatric End-Stage Liver Disease/Model for End-Stage Liver Disease (MELD) scores, diagnosis, and weight among pediatric candidates and matching for MELD score, height, and offer among adult candidates. Among pediatric candidates ≤7 kg, split liver offer acceptance versus decline was associated with a 63% reduction in mortality (adjusted hazard ratio [aHR], _0.17 0.37_0.80 [P = 0.01]; 93.1% versus 84.0% 1-year survival after decision). Within 1 year of decline for those ≤7 kg, 6.4% died and 31.1% received a WLT. Among pediatric candidates >7 kg, there was no significant difference associated with acceptance of a split liver offer (aHR, _0.63 1.07_1.82 [P = 0.81]; 91.7% versus 94.4% 1-year survival after decision). Within 1 year of decline for those >7 kg, 1.8% died and 45.8% received a WLT. Among adult candidates, split liver offer acceptance was associated with a 43% reduction in mortality (aHR, _0.39 0.57_0.83 [P = 0.005]; 92.2% versus 84.4% 1-year survival after decision). Within 1 year of decline for adult candidates, 7.9% died and 39.3% received a WLT. Accepting split liver offers for SLT could significantly improve survival for small children and adults on the waiting list.

Left lateral segment pediatric liver transplantation: a 25 year experience at Mount Sinai

BACKGROUND

Outcomes of left lateral segment (LLS) grafts in pediatric recipients were compared between living (LD-LLS) and deceased donor (DD-LLS) grafts.

METHODS

195 LLS grafts (99DD-LLS-96LD-LLS) were analyzed with a median follow-up of 9.1years. The primary endpoints were overall patient/graft survival.

RESULTS

LD-LLS grafts were younger (0.9vs.1.4years, p = 0.039), more likely to have a fulminant liver failure (17.9%vs.5.3%,p = 0.002), less likely to have a metabolic disorder (6.3%vs.25.5%,p = 0.002), and less likely to be undergoing retransplantation (5.3% vs.16.2%,p = 0.015). There was a trend toward decreased hepatic artery thrombosis in LD-LLS grafts (6.6% vs. 15.5%,p = 0.054). No differences in the overall biliary complications occurred. The LD-LLS group had prolonged survival compared to the DD-LLS group with 10-year survival rates of 81%, and 74% (p = 0.005), respectively. LD-LLS grafts had longer graft survival compared to DD-LLS grafts (10-year graft survival 85%vs.67%,p = 0.005). Recipient age >1year (HR 2.39,p = 0.026), aortic reconstruction (HR 2.12,p = 0.046) and vascular complication (HR 3.12,p < 0.001) were independent predictors of poor patient survival. Non-biliary liver disease (HR 2.17,p = 0.015), DD-LLS (HR 2.06,p = 0.034) and vascular complication (HR 4.61,p < 0.001) were independent predictors of poor graft survival.

CONCLUSION

The use of SLT remains a viable option with excellent long-term outcomes. We show improved graft and patient survival with living donor grafts.

Living Donor Liver Transplant Center Volume Influences Waiting List Survival Among Children Listed for Liver Transplantation

BACKGROUND

Pediatric living donor liver transplantation (LDLT) remains infrequently performed in the United States and localized to a few centers. This study aimed to compare pediatric waiting list and posttransplant outcomes by LDLT center volume.

METHODS

The Scientific Registry of Transplant Recipients/Organ Procurement and Transplantation Network database was retrospectively reviewed for all pediatric (age <18 y) liver transplant candidates listed between January 1, 2009, and December 31, 2019. The average annual number of LDLT, deceased donor partial liver transplant (DDPLT), and overall (ie, LDLT + DDPLT + whole liver transplants) pediatric liver transplants performed by each transplant center during the study period was calculated.

RESULTS

Of 88 transplant centers, only 44 (50%) performed at least 1 pediatric LDLT during the study period. LDLT, DDPLT, and overall transplant center volume were all positively correlated. LDLT center volume was protective against waiting list dropout after adjusting for confounding variables (adjusted hazard ratio, 0.92; 95% confidence interval, 0.86-0.97; P = 0.004), whereas DDPLT and overall center volume were not (P > 0.05); however, DDPLT center volume was significantly protective against both recipient death and graft loss, whereas overall volume was only protective against graft loss and LDLT volume was not protective for either.

CONCLUSIONS

High-volume pediatric LDLT center can improve waiting list survival, whereas DDPLT and overall volume are associated with posttransplant survival. Expertise in all types of pediatric liver transplant options is important to optimize outcomes.

Whole liver transplantation in children under 10 kg: How to minimize the high risks of a still challenging procedure

BACKGROUND

Whole liver transplantation in infants <10 kg is a rare procedure with moderate outcomes (67%-79% graft survival at 1 year) and high rates of vascular complications (hepatic artery thrombosis 5-26%).

METHODS

Retrospective single-center analysis of whole liver transplantation in infants <10 kg and systematic review of the literature focused on survival rates and surgical complications.

RESULTS

Between January 2005 and December 2020, 175 liver transplantations in 173 children were performed at our center. A total of 92 (53%) children weighed less than 10 kg; 19 (21%) of them underwent WLT and constitute the study population. Median age of the recipients was 10 months (21 days-24 months) and median body weight 6.5 (3.1-9.8) kg. Median age of the donors was 5 (1-84) months and median body weight 6.1 (4-21) kg. Median donor-to-recipient body weight ratio was 1.2 (range: 0.6-4.5). Postoperatively, neither hepatic artery nor portal vein thrombosis occurred. A biliary complication occurred in 4 cases: 1 bile leak (early), 3 anastomotic stenoses (1 delayed and 2 late), and 1 non-anastomotic stenosis (late). Patient survival rate at 1, 5, and 10 years was 100%, 92%, and 92%, respectively. Overall, death-censored graft survival after 1, 5, and 10 was 100%.

CONCLUSION

Our results are excellent in terms of complications and graft and patient survival. This involves not only high-end surgical performance but also close interdisciplinary perioperative cooperation based on strong standard operating procedures and mainly focused on fluid management, hemostasiology, and strict monitoring of vessel patency.

North American Biliary Stricture Management Strategies in Children After Liver Transplantation: A Multicenter Analysis From the Society of Pediatric Liver Transplantation (SPLIT) Registry

Biliary strictures affect 4%-12% of pediatric liver transplantations. Biliary strictures can contribute to graft loss if left untreated; however, there remains no consensus on the best course of treatment. Study objectives included analyses of outcomes associated with biliary stricture management strategies via percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography (ERCP), or surgery. We identified pediatric liver transplantation recipients (2011-2016) with biliary strictures from the Society of Pediatric Liver Transplantation (SPLIT) registry and retrieved imaging, procedural, and operative reports from individual centers. Subanalyses were performed to specifically evaluate PTC and ERCP for "optimal biliary outcome" (OBO), defined as graft survival with stricture resolution and without recurrence or surgery. A total of 113 children with a median follow-up of 3.9 years had strictures diagnosed 100 days (interquartile range, 30-290) after liver transplantation; 81% were isolated anastomotic strictures. Stricture resolution was achieved in 92% within 101 days, more frequently with isolated anastomotic strictures (96%). 20% of strictures recurred, more commonly in association with hepatic artery thrombosis (32%). Patient and graft survival at 1 and 3 years were 99% and 98% and 94% and 92%, respectively. In a subgroup analysis of 79 patients with extrahepatic strictures managed by PTC/ERCP, 59% achieved OBO following a median of 4 PTC, and 75% following a median of 3 ERCP (P < 0.001). Among patients with OBO, those with ERCP had longer time intervals between successive procedures (41, 47, 54, 62, 71 days) than for PTC (27, 31, 36, 41, 48 days; P < 0.001). Allograft salvage was successful across all interventions. Stricture resolution was achieved in 92%, with 20% risk of recurrence. Resolution without recurrence was highest in patients with isolated anastomotic strictures and without hepatic artery thrombosis.

Pediatric liver transplantation outcomes from a single center in Thailand

BACKGROUND

Liver transplantation (LT) has become an acceptable curative method for children with several liver diseases, especially irreversible acute liver failure and chronic liver diseases. King Chulalongkorn Memorial Hospital is one of Thailand's largest liver transplant centers and is responsible for many pediatric cases.

AIM

To report the experience with pediatric LT and evaluate outcomes of living-related vs deceased-donor grafts.

METHODS

This evaluation included children who underwent LT between August 2004 and November 2019. Data were retrospectively reviewed, including demographics, diagnoses, laboratory values of donors and recipients, the pediatric end-stage liver disease (PELD) or model for end-stage liver disease (MELD) score, graft source, wait time, perioperative course, postoperative complications, and survival rates. Continuous data were reported using the median and interquartile range. The Mann-Whitney U-test was used to compare the wait time between the living-related and deceased-donor groups. The chi-square or Fisher's exact test were used to compare the frequencies of between-group complications. Survival rates were calculated using the Kaplan-Meier method.

RESULTS

Ninety-four operated pediatric liver transplant patients were identified (54% were females). The median age at transplantation was 1.2 (0.8-3.8) years. The median PELD and MELD scores were 20 (13-26.8) and 19.5 (15.8-26.3), respectively. Most grafts (81.9%) were obtained from living-related donors. The median wait time for the living donors was significantly shorter compared with the deceased donors at 1.6 (0.3-3.1) mo vs 11.2 (2.1-33.3) mo (P = 0.01). Most patients were diagnosed with biliary atresia (74.5%), and infection was the most common complication within 30 d post-transplantation (14.9%). Without a desensitization protocol, 9% of transplants were ABO-incompatible. Eight hepatitis B core antibodies (anti-HBc)-negative recipients received positive anti-HBc grafts without different observed complications. The overall survival rate was 93.6% and 90.3% at 1 and 5 years, respectively. No graft loss during follow-up was noted among survivors.

CONCLUSION

A significant number of pediatric LT cases were reported in Thailand. Based on relatively comparable outcomes, ABO-incompatible and HBc antibody-positive grafts may be considered in an organ shortage situation.

Over 30 Years of Pediatric Liver Transplantation at the Charité-Universitätsmedizin Berlin

Background: Pediatric liver transplantation (LT) is the treatment of choice for children with end-stage liver disease and in certain cases of hepatic malignancies. Due to low case numbers, a technically demanding procedure, the need for highly specialized perioperative intensive care, and immunological, as well as infectious, challenges, the highest level of interdisciplinary cooperation is required. The aim of our study was to analyze short- and long-term outcomes of pediatric LT in our center. Methods: We conducted a retrospective single-center analysis of all liver transplantations in pediatric patients (≤16 years) performed at the Department of Surgery, Charité – Universitätsmedizin Berlin between 1991 and 2021. Three historic cohorts (1991–2004, 2005–2014 and 2015–2021) were defined. Graft- and patient survival, as well as perioperative parameters were analyzed. The study was approved by the institutional ethics board. Results: Over the course of the 30-year study period, 212 pediatric LTs were performed at our center. The median patient age was 2 years (IQR 11 years). Gender was equally distributed (52% female patients). The main indications for liver transplantation were biliary atresia (34%), acute hepatic necrosis (27%) and metabolic diseases (13%). The rate of living donor LT was 25%. The median cold ischemia time for donation after brain death (DBD) LT was 9 h and 33 min (IQR 3 h and 46 min). The overall donor age was 15 years for DBD donors and 32 years for living donors. Overall, respective 1, 5, 10 and 30-year patient and graft survivals were 86%, 82%, 78% and 65%, and 78%, 74%, 69% and 55%. One-year patient survival was 85%, 84% and 93% in the first, second and third cohort, respectively (p = 0.14). The overall re-transplantation rate was 12% (n = 26), with 5 patients (2%) requiring re-transplantation within the first 30 days. Conclusion: The excellent long-term survival over 30 years showcases the effectiveness of liver transplantation in pediatric patients. Despite a decrease in DBD organ donation, patient survival improved, attributed, besides refinements in surgical technique, mainly to improved interdisciplinary collaboration and management of perioperative complications.

Predictors of patient and graft survival following pediatric liver transplantation: Long-term analysis of more than 300 cases from single centre

BACKGROUND

Pediatric liver transplant (PLT) activity has flourished over time although with limited expansion in the graft pool. The study aims to identify pre-transplant factors that predict post-transplant patient and graft survival in the PLT population.

METHODS

Retrospective review of PLTs at a single tertiary transplant unit from 2000 to 2019. Univariate and multivariate analyses of pre-transplant factors were performed to identify predictors of patient and graft survival.

RESULTS

Two hundred and seventy-six patients received 320 PLTs. The most common cause of graft loss was hepatic artery thrombosis (n = 13, 29.6%). The most common cause of mortality was sepsis (n = 11, 29.7%). Univariate analysis showed that the following variables had a significant (p < .05) impact on patient survival: recipient age, weight, height, graft type (technical variant graft), transplant category (acute liver failure), the era of transplant, and invasive ventilation. The following variables had a significant (p < .05) impact on graft survival: recipient age, weight, height, transplant category (acute liver failure), and the era of transplant. Multivariate analysis precluded the era of transplant as the only significant factor for patient survival; patients transplanted after 2005 had significantly higher patient survival. No independent factor predicting graft survival was identified. For children transplanted after 2005, the only factor that predicted patient survival was pre-transplant invasive ventilation.

CONCLUSIONS

Our study suggests that the learning curve and pre-transplant invasive ventilation in the recipient have a significant impact on patient survival. The traditional view of worse outcomes of smaller PLT candidates should be changed.

Impact of Monosegment Graft Use for Infants in Pediatric Living Donor Liver Transplantation

BACKGROUND

Left lateral segment grafts are generally used for very young pediatric patients undergoing living donor liver transplantation (LDLT). Recently, graft reduction techniques were developed for LDLT. Monosegment grafting has been used in newborns. The aim of this study was to determine the usefulness of monosegment grafting for infants.

METHODS

Recipients <2 years of age who underwent LDLT with a monosegment graft between 2010 and 2020 were gathered. Parents comprised all LDLT donors. A segment 2 monosegment graft was resected as a graft from the donor. Standard liver volume (SLV) was estimated using Urata's equation. Graft type, graft weight (GW), and native liver weight were assessed.

RESULTS

Eight patients were included in the study. Original diseases consisted of biliary atresia (n = 6) and fulminant hepatitis (n = 2). Final graft type included monosegment (n = 5) and reduced monosegment (n = 3). Median final GW/body weight after reduction was 3% (range, 2%-3.4%). Median native liver weight/SLV was 134% except in patients with fulminant hepatitis. Median pre-reduction graft volume (GV)/estimated GV was 113% (range, 60%-208%). Median pre-reduction GV/SLV of monosegment grafts that required reduction (n = 3) was 109% (range, 106%-121%). Median final reduced graft GV/SLV was 80% (range, 74%-91%). Complications due to large-for-size grafts were not observed. One case of bile leakage due to graft reduction occurred as a complication. Grafts were functioning well with the exception of one graft loss due to antibody-mediated rejection.

CONCLUSION

Estimated GV in infants varies widely. Monosegment grafting can be useful for infants as well as newborns.

Are split liver grafts a suitable option in high-risk liver transplant recipients?

PURPOSE OF REVIEW

To assess the outcomes of split liver transplantation (SLT) in adults and children and evaluate its role in high-risk recipients with a high model for end-stage liver disease (MELD) score, an urgent indication or requiring retransplantation.

RECENT FINDINGS

Split liver grafts in general have equivalent long-term survival outcomes to whole grafts despite an increase in biliary complications. Recent success and technical advances have encouraged use of these grafts in high-risk recipients. Split liver grafts can be used successfully in recipients with a high MELD score if there is adequate weight-matching. There are mixed results in urgent indication recipients and for retransplantation such that use in this group of patients remains controversial.

SUMMARY

SLT addresses donor shortages by facilitating the transplant of two recipients from the same donor liver. By using careful donor and recipient selection criteria, SLT can achieve equivalent long-term outcomes to whole grafts. These grafts have been used successfully in recipients with a high MELD score, but should be used selectively in urgent indication recipients and for retransplantation.

Contrast-enhanced ultrasound of transplant organs - liver and kidney - in children

Ultrasound (US) is the first-line imaging tool for evaluating liver and kidney transplants during and after the surgical procedures. In most patients after organ transplantation, gray-scale US coupled with color/power and spectral Doppler techniques is used to evaluate the transplant organs, assess the patency of vascular structures, and identify potential complications. In technically difficult or inconclusive cases, however, contrast-enhanced ultrasound (CEUS) can provide prompt and accurate diagnostic information that is essential for management decisions. CEUS is indicated to evaluate for vascular complications including vascular stenosis or thrombosis, active bleeding, pseudoaneurysms and arteriovenous fistulas. Parenchymal indications for CEUS include evaluation for perfusion defects and focal inflammatory and non-inflammatory lesions. When transplant rejection is suspected, CEUS can assist with prompt intervention by excluding potential underlying causes for organ dysfunction. Intracavitary CEUS applications can evaluate the biliary tract of a liver transplant (e.g., for biliary strictures, bile leak or intraductal stones) or the urinary tract of a renal transplant (e.g., for urinary obstruction, urine leak or vesicoureteral reflux) as well as the position and patency of hepatic, biliary and renal drains and catheters. The aim of this review is to present current experience regarding the use of CEUS to evaluate liver and renal transplants, focusing on the examination technique and interpretation of the main imaging findings, predominantly those related to vascular complications.

Influence of early biliary complications on survival rates after pediatric liver transplantation-A positive outlook

BACKGROUND

Early biliary complications (EBC) constitute a burden after pediatric liver transplantation frequently requiring immediate therapy. We aimed to assess the impact of EBC on short- and long-term patient and graft survival as well as post-transplant morbidity.

METHODS

We analyzed 121 pediatric liver transplantations performed between 1984 and 2019 at the Medical University of Innsbruck for the occurrence of early (<90 days) biliary complications and investigated the influence of EBC on patient and graft survival.

RESULTS

Early biliary complications occurred in 30 (24.8%) out of the 121 pediatric liver transplant recipients. Patient survival at 15 years (89.2% vs. 84.2%, p = .65) and all-cause (82.5% vs. 74.0%) and death-censored graft survival (82.5% vs. 75.1%, p = .71) at 10 years were similar between the EBC and the non-EBC group. The EBC group had a significantly longer ICU (25 vs. 16 days, p < .001) and initial hospital stay (64 vs. 42 days, p = .002). Livers of patients with EBC were characterized by multiple bile ducts (33.3% vs. 13.2%, p = .027), and patients with EBC had a higher risk to develop late biliary complications (OR 2.821 [95% CI 1.049-7.587], p = .044) and bowel obstruction/perforation (OR 4.388 [95% CI 1.503-12.812], p = .007).

CONCLUSION

Early biliary complications after pediatric liver transplantation is frequent. The occurrence of EBC significantly increased post-transplant morbidity without affecting mortality. Multiple bile ducts were the only risk factor for the development of EBC in our cohort.

Living Donor Versus Deceased Donor Pediatric Liver Transplantation: A Systematic Review and Meta-analysis

Reduced-size deceased donors and living donor liver transplantation (LDLT) can address the organ shortage for pediatric liver transplant candidates, but concerns regarding technical challenges and the risk of complications using these grafts have been raised. The aim of this study was to compare outcomes for pediatric LDLT and deceased donor liver transplantation (DDLT) via systematic review.

METHODS

A systematic literature search was performed to identify studies reporting outcomes of pediatric (<18 y) LDLT and DDLT published between 2005 and 2019. A meta-analysis was conducted to examine peri- and postoperative outcomes using fixed- and random-effects models.

RESULTS

Overall, 2518 abstracts were screened, and 10 studies met criteria for inclusion. In total, 1622 LDLT and 6326 DDLT pediatric patients from 4 continents were examined. LDLT resulted in superior patient survival when compared with DDLT at 1, 3, and 5 y post-LT (1-y hazard ratio: 0.58, 95% confidence interval [CI] 0.47-0.73, P < 0.0001). Similarly, LDLT resulted in superior graft survival at all time points post-LT when compared with DDLT (1-y hazard ratio: 0.56 [95% CI 0.46-0.68], P < 0.0001]. The OR for vascular complications was 0.73 (95% CI 0.39-1.39) and 1.31 (95% CI 0.92-1.86) for biliary complications in LDLT compared with DDLT, whereas LDLT was associated with lower rates of rejection (OR: 0.66 [95% CI 0.45-0.96], P = 0.03).

CONCLUSIONS

This meta-analysis demonstrates that LDLT may offer many advantages when compared with DDLT in children and suggests that LDLT should continue to be expanded to optimize outcomes for pediatric LT candidates.

The Surge in Deceased Liver Donors Due to the Opioid Epidemic: Is It Time to Split the Difference?

BACKGROUND

This study aimed to compare trends in use of drug overdose (DO) donors in adult versus pediatric liver transplants and the utilization of split liver transplantation in this donor population.

METHODS

The United Network for Organ Sharing database was reviewed for deceased donor liver transplants from March 2002 to December 2017. Recipients were categorized by donor mechanism of death. Donor splitting criteria was defined as age <40 y, single vasopressor or less, transaminases no >3 times the normal limit, and body mass index ≤ 28 kg/m2.

RESULTS

Adult liver transplants from DO donors increased from 2% in 2002 to 15% in 2017, while pediatric liver transplants from DO donors only increased from <1% to 3% in the same time. While 28% of DO donors met splitting criteria, only 3% of those meeting splitting criteria were used as a split graft. Both pediatric and adult recipients of DO donor livers achieved excellent patient and graft survival.

CONCLUSIONS

DO donors are underutilized in pediatric liver transplantation. Increased splitting of DO donor livers could significantly decrease, if not eliminate, the pediatric liver waiting list.

Comparison of cystatin C, creatinine, and iohexol clearance in pediatric liver transplantation-a retrospective cohort study

Impaired renal function after pediatric (LT) is a recognized problem. Accurate monitoring of (GFR) is imperative to detect declining renal function. GFR can be estimated via s-creatinine and/or p-cystatin C or measured by inulin and or/iohexol clearances. We retrospectively compared eGFRcrea and eGFRcyst, to mGFRiohex after LT. Data from 91 children with 312 concomitant measurements of s-creatinine, p-cystatin C, and iohexol clearance, obtained between 2007 and 2015, were analyzed. eGFR was calculated by using the p-cystatin C-based CAPA and CKD-EPI formulas, and the s-creatinine-based Schwartz-LYON, FAS, revised Schwartz and MDRD formulas. Also, the arithmetic means of cystatin C-based and creatinine-based equations were used. Every calculated eGFR was compared to mGFRiohex in statistical correlation, accuracy, precision, bias, and misclassifications. Among the different equations, p-cystatin C-based formulas (CAPA and CKD-EPI) as well as the s-creatinine-based Schwartz-LYON formula showed the most correct estimates regarding accuracy (84-87.5%), bias (0.19-4.0 ml/min/1.73 m² ), and misclassification rate (24.7-25%). In patients with renal function <75 ml/min/1.73 m² , cystatin C-based formulas were significantly more accurate and less biased than creatinine-based formulas. In conclusion, S-creatinine could be used in a clinical setting on a regular basis in liver transplanted pediatric patients, with reliable results, if eGFR is calculated by the Schwartz-LYON formula. When suspected renal dysfunction, cystatin C-based eGFR should be calculated, since it gives more accurate and less biased estimates than creatinine-based eGFR, and should be confirmed by mGFR (iohexol).

Serum bile acid levels assist the prediction of biliary stricture and survival after liver transplantation in children

Biliary stricture is an important biliary complication after liver transplant in children. We aimed to investigate the utility of serum bile acid levels for prediction of biliary stricture in children after liver transplant. This study enrolled 60 children who underwent liver transplantation at a mean age of 2.04±0.30 years; serum bile acid levels were surveyed in a cross-sectional design. These patients were followed regularly at our institute, and the clinical data were collected prospectively. The major indication of liver transplant in this pediatric cohort was biliary atresia (78.33%). During the follow-up period (3.08±0.30 years), nine patients (15%) developed biliary stricture after the check of serum bile acid. A receiver operating characteristic curve analysis yielded a serum bile acid cutoff of >40 μM for the prediction of biliary stricture (P = 0.002). A serum bile acid level >40 is the most important predictor of a biliary stricture after liver transplant (odds ratio=65.65, P = 0.003) after adjusting for gender and GGT levels. The phenomenon remained on Cox's proportional hazard survival analysis (hazard ratio =15.42, P = 0.001). The mortality risk after liver transplant was significantly higher in subjects with serum bile acid levels >40 μM than in those with levels ≤40 μM (log-rank test, P = 0.004).Conclusion: Serum bile acid levels can be used for non-invasive screening and prediction of biliary stricture and mortality in children after liver transplantation. What is Known: • Biliary stricture is a major biliary complication after pediatric liver transplantation, and we showed the serum bile acid level significantly associates with biliary stricture. What is New: • In this study, we demonstrated the serum bile acid level may assist in the early detection of biliary stricture and mortality non-invasively.

Internal split liver transplants reduce the waiting list time for teenagers with a low calculated Model for End-stage Liver Disease score

BACKGROUND

Split liver transplantation allows for the simultaneous transplantation of two patients, typically a child and an adult, with a single organ. We report our experience with "internal splits" in which 10 pediatric patients from our institution were transplanted with five organs. We hypothesized that this would reduce the WL time for teenagers with a low calculated MELD score.

METHODS

A retrospective chart review of those 10 patients was done. Their WL time was compared with local, regional, and national data. P < .05 was considered significant.

RESULTS

The median age of the five primary recipients to whom the liver was first allocated was 2.3 years (0.7-7.4) (median weight 10.4 kg (8.4-17.7)). They received a segment 2-3 graft. Five "secondary" recipients (median age 17.4 years (16.6-18.9); median weight 66.2 kg (53.7-70.0)) were identified on our WL to receive the trisector graft. At transplant, their median calculated MELD score was 11 (8-20). Their mean WL time (241.6 ± 218.9 days) was significantly shorter than local (480.6 ± 833.6 days), regional (370.4 ± 563.4 days), and national patients (245.6 ± 465.4 days) with MELD ≤ 20 (P = .047). There was no significant difference between their WL time and that of patients with a MELD 8 ≤ x≤31 (equivalent to their median exception score, P = .63). Patient and graft survival was 100% for all 10 patients.

CONCLUSION

In our experience, simultaneous internal split liver transplantation allowed teenagers with a low calculated MELD score to be transplanted faster than patients with a similar score. Promoting the use of internal split liver transplantation could help reduce the pediatric waitlist mortality.