Living donor liver transplantation in maple syrup urine disease - Case series and world's youngest domino liver donor and recipient

Changes in branched-chain amino acids in an infant with maple syrup urine disease during perioperative pediatric liver transplant: A case report

An 11-month-old female infant diagnosed with classic subtype IB maple syrup urine disease underwent living donor liver transplantation. Blood samples for plasma amino acid analysis were collected during the three phases of the operation. Despite the perioperative prophylactic administration of 12.5% hypertonic dextrose solution with insulin and a 20% intralipid emulsion, the blood levels of the branched-chain amino acids increased dramatically during surgery, consistent with an acute intraoperative metabolic decompensation. However, these blood levels normalized soon after liver transplantation with an excellent outcome. We suggest that the occurrence of an intraoperative metabolic crisis during liver transplantation is not necessarily a sign of graft failure.

Domino liver transplantation for maple syrup urine disease in children: A single-center case series

BACKGROUND

Domino liver transplant (DLT) represents another type of liver donor to expand the donor pool. Recent reports of successful DLT in children with maple syrup urine disease (MSUD) show promising long-term outcomes.

METHODS

It was a retrospective study. All children with MSUD were paired with either recipients with end-stage liver disease (ESLD) or non-MSUD metabolic disease. Each pair underwent simultaneous liver transplant (LT), where the MSUD recipient received the graft from a living-related donor and the liver explanted from the MSUD donor was transplanted to the respective paired domino recipient. We report our experience regarding the techniques and outcomes of DLT at our center.

RESULTS

Eleven children with MSUD and 12 respective DLT recipients were enrolled, one of which was domino split-liver transplantation. DLT recipients included seven ESLD, two propionic acidemia (PA), one glycogen storage disease(GSD) type-1, one GSD type-3, and one Citrullinemia. Post-LT ICU and hospital stays were comparable (p > .05). Patient and graft survival was 100% and 66.6% in the MSUD group and DLT recipients at a mean follow-up of 13.5 and 15 months. There was no death in the MSUD group as compared to four in the DLT group. The amino acid levels rapidly normalized after the LT in the children with MSUD and they tolerated the normal unrestricted diet. No vascular, biliary, or graft-related complications were seen in the post-transplant period. No occurrence of MSUD was noted in DLT recipients.

CONCLUSION

DLTs have excellent post-surgical outcomes. DLT should be strongly considered and adopted by transplant programs worldwide to circumvent organ shortage.

Long-term results of liver transplantation for maple syrup urine disease: A single-center experience in Turkey

OBJECTIVES

Maple syrup urine disease (MSUD) is an autosomal recessive inherited disorder. Despite the advances in medical nutrition therapies, classical phenotype causes severe neurological disorders and sudden death. It is known that MSUD patients do not experience metabolic attacks despite their free diet after liver transplantation (LT). This study aims to reveal the long-term results, development, mental, motor, intellectual and nutritional status of MSUD patients who underwent LT.

METHODS

The data of 12 patients who underwent deceased donor (5 recipients) and living donor liver transplantation (7 recipients) were retrospectively analyzed. The age, genotype, psychometric and mental status, development, BCAA values, type of LT, donor-recipient proximity, complications, and survival were assessed.

RESULTS

There were 4 (33%) girls and 8 (67%) boys. The mean current age was 9.33 ± 4.58 years. The mean follow-up time was 3 ± 2.5 years. The repeated measures of leucine and isoleucine values revealed that there were no significant differences from the pre-LT to post-LT 1-year. The protein-restricted nutrition was switched to a free diet when oral intake was opened after LT. None of the recipients experienced metabolic attacks after the living donor or deceased donor LT. The 1-, 3-, and 5-year survival rate of the patients is 83.3%. There was no significant difference in survival between living and deceased donor liver transplantation.

CONCLUSIONS

Liver transplantation is a treatment option for MSUD in proper conditions to save the patient life, increase the quality of life, and provide essential amino acids with free diet intake for growth and development.

Surgical technique and the long-term outcomes of pediatric living donor domino liver transplantation from patients with maple syrup urine disease

BACKGROUND

The native liver of patients with maple syrup urine disease (MSUD) (1st recipients) can be used as a graft for non-MSUD patients with end-stage liver disease (2nd recipients). This study aimed to demonstrate the optimal operational procedures and the long-term outcomes of 2nd recipients.

METHODS

Six 2nd recipients of living donor domino liver transplantation (LD-DLT) (age: 42.5 [22-169] months at DLT) received a native liver as a graft from an MSUD patient at our hospital between June 2014 and April 2020. We reviewed the operational procedures and outcomes of 2nd recipients after LD-DLT.

RESULTS

The 2nd recipients' original diseases included biliary atresia, congenital hepatic fibrosis, congenital protein C deficiency, familial hypercholesterolemia, hepatoblastoma, and mitochondrial hepatopathy. Five of the six recipients had a whole liver and one had a right lobe graft. The site at which the vessels of the MSUD liver were dissected prioritized the safety of the 1st recipient. At the end of follow-up, all recipients were doing well without surgical complications. The mean serum amino acid values of the 2nd recipients did not exceed the upper limit of the reference values during the long-term observation period. All patients showed normal growth while maintaining the same z-score of height and weight after LD-DLT as the preoperative level.

CONCLUSION

The liver of patients with MSUD can be used safely without concern regarding long-term complications or de novo MSUD development. LD-DLT using the MSUD liver can expand the donor pool as an alternative graft in pediatric LT.

Domino transplantation for pediatric liver recipients: Obstacles, challenges, and successes

BACKGROUND

Domino liver transplantation aims to address the need to increase the liver donor supply. In a domino liver transplant, the domino recipient receives the explanted liver from the recipient of a traditional liver transplant. The domino donor typically requires liver transplant to correct a metabolic disorder; the explanted liver thus has a single gene defect but otherwise normal structure and function.

METHODS

In this review, we detail the history of domino liver transplantation, appropriate domino donor indications, the technical advances to the surgical approach, current outcomes, and future opportunities.

RESULTS

Development of de novo disease in the domino recipient has relegated adult domino liver transplant to be considered a source of marginal donor livers. However, pediatric domino liver transplant has leveraged certain metabolic disorders, especially maple syrup urine disease, in which the liver enzyme deficiency can be compensated by the systemic presence of sufficient enzyme. Advances in the surgical aspects of assuring adequate length of vasculature have improved the safety of the procedure in both domino donors and recipients.

CONCLUSIONS

Pediatric domino liver transplant utilizing domino donors with specific metabolic liver diseases should be considered a viable live donor option for children awaiting liver transplant.

Pediatric metabolic liver diseases: Evolving role of liver transplantation

Metabolic liver diseases (MLD) are the second most common indication for liver transplantation (LT) in children. This is based on the fact that the majority of enzymes involved in various metabolic pathways are present within the liver and LT can cure or at least control the disease manifestation. LT is also performed in metabolic disorders for end-stage liver disease, its sequelae including hepatocellular cancer. It is also performed for preventing metabolic crisis', arresting progression of neurological dysfunction with a potential to reverse symptoms in some cases and for preventing damage to end organs like kidneys as in the case of primary hyperoxalosis and methyl malonic acidemia. Pathological findings in explant liver with patients with metabolic disease include unremarkable liver to steatosis, cholestasis, inflammation, variable amount of fibrosis, and cirrhosis. The outcome of LT in metabolic disorders is excellent except for patients with mitochondrial disorders where significant extrahepatic involvement leads to poor outcomes and hence considered a contraindication for LT. A major advantage of LT is that in the post-operative period most patients can discontinue the special formula which they were having prior to the transplant and this increases their well-being and improves growth parameters. Auxiliary partial orthotopic LT has been described for patients with noncirrhotic MLD where a segmental graft is implanted in an orthotopic position after partial resection of the native liver. The retained native liver can be the potential target for future gene therapy when it becomes a clinical reality.

Hyperleucinosis during infections in maple syrup urine disease post liver transplantation

Maple syrup urine disease (MSUD) is due to biallelic variants in one of the three genes: BCKDHA, BCKDHB, and DBT. Branched-chain alpha-ketoacid dehydrogenase complex deficiency and elevated leucine, valine, isoleucine and alloisoleucine in body fluids are the results. We report hyperleucinosis during intercurrent illnesses in six patients with MSUD post liver transplantation. Patient charts were retrospectively reviewed. Data was entered into an Excel Database. Literature was reviewed. Six patients with MSUD were included who had post liver transplantation hyperleucinosis during an intercurrent illness. Five had encephalopathy. One received hemodialysis for the management of hyperleucinosis. All patients had unrestricted diet. Additionally, there were five patients (one patient included into the current study) reported in the literature. We suggested management considerations for the follow-up of patients with MSUD post liver transplantation after the first episode of unexplained encephalopathy or signs of acute hyperleucinosis during intercurrent illness due to our clinical experience: 1) Healthy: Unrestricted diet and monitoring of leucine levels; 2) Illness: a) home illness management: increased carbohydrate intake b) illness management at hospital: intravenous dextrose, intravenous lipid and daily plasma amino acid monitoring. We report hyperleucinosis and/or encephalopathy as a rare event post liver transplantation in MSUD as a multicenter case series. Hyperleucinosis and/or encephalopathy may occur in both related and unrelated donor liver transplantation. Based on the long-term follow-up of those patients, these suggested management considerations may be revised as per the patients' needs.

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Patients with MSUD can present with hyperleucinosis during intercurrent illness post liver transplantation.

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Hyperleucinosis in MSUD post liver transplantation can occur in related and unrelated donor liver transplantation.

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Monitoring of patients with MSUD is required after their first episode of hyperleucinosis post liver transplantation.

Living Related Liver Transplantation for Metabolic Liver Diseases in Children

ABSTRACT

Metabolic liver diseases (MLDs) are a heterogeneous group of inherited conditions for which liver transplantation can provide definitive treatment. The limited availability of deceased donor organs means some who could benefit from transplant do not have this option. Living related liver transplant (LrLT) using relatives as donors has emerged as one solution to this problem. This technique is established worldwide, especially in Asian countries, with shorter waiting times and patient and graft survival rates equivalent to deceased donor liver transplantation. However, living donors are underutilized for MLDs in many western countries, possibly due to the fear of limited efficacy using heterozygous donors. We have reviewed the published literature and shown that the use of heterozygous donors for liver transplantation is safe for the majority of MLDs with excellent metabolic correction. The use of LrLT should be encouraged to complement deceased donor liver transplantation (DDLT) for treatment of MLDs.

Technique and outcome of domino liver transplantation from patients with maple syrup urine disease: Expanding the donor pool for live donor liver transplantation

AIM/BACKGROUND

Domino liver transplantation (DLT) using liver allografts from patients with metabolic disorders enhances organ utilization. Short- and long-term course and outcome of these patients can impact the decision to offer this procedure to patients, especially those with diseases that can potentially be cured with liver transplant. We reviewed the outcomes of DLT from maple syrup urine disease (MSUD) patients in our large academic pediatric and adult transplant program.

METHODS

All patients receiving DLT were analyzed retrospectively with a minimum of one-year follow-up period for patient and donor characteristics, early and late postoperative complications and patient and graft survival with their MSUD donors in terms of age, weight, MELD/PELD scores, cold ischemia time, postoperative leucine levels, and peak ALT (alanine aminotransferase) levels during the first 48 postoperative hours.

RESULTS

Between 2006 and May 2019, 21 patients underwent domino liver transplantation with live donor allografts from MSUD patients. Four patients transplanted for different metabolic diseases are focus of a separate report. Seventeen patients with minimum one-year follow-up period are reported herein. The indications were primary sclerosing cholangitis (PSC, n = 4), congenital hepatic fibrosis (CHF, n = 2), alpha-1 antitrypsin deficiency (A-1 ATD, n = 2), progressive familial intrahepatic cholestasis (PFIC, n = 2), cystic fibrosis (n = 1), primary biliary cirrhosis (PBC, n = 1), neonatal hepatitis (n = 1), embryonal sarcoma (n = 1), Caroli disease (n = 1), hepatocellular carcinoma (HCC, n = 1), and chronic rejection after liver transplantations for PSC (n = 1). All patients and grafts survived at median follow-up of 6.4 years (range 1.2-12.9 years). Median domino recipient age was 16.2 years (range 0.6-64.6 years) and median MSUD recipient age was 17.6 years (range 4.8-32.1 years). There were no vascular complications during the early postoperative period, one patient had portal vein thrombosis 3 years after DLT and a meso-Rex bypass was successfully performed. Small for size syndrome (SFSS) occurred in reduced left lobe DLT recipient and was managed successfully with conservative management. Biliary stricture developed in 2 patients and was resolved by stenting. Comparison between DLT and MSUD recipients' peak postoperative ALT results and PELD/MELD scores showed lower levels in DLT group (P-value <.05).

CONCLUSIONS

Patient and graft survival in DLT from MSUD donors was excellent at short- and long-term follow-up. Metabolic functions have been normal in all recipients on a normal unrestricted protein diet. Ischemia preservation injury based on peak ALT was significantly decreased in DLT recipients. Domino transplantation from pediatric and adult recipients with selected metabolic diseases should be increasingly considered as an excellent option and alternative to deceased donor transplantation, thereby expanding the living donor pool. This, to date, is the largest world experience in DLT utilizing livers from patients with MSUD.

Domino Liver Transplant in Maple Syrup Urine Disease: Technical Details of Cases in Which the First Surgery Involved a Living Donor

BACKGROUND

Data describing the technical aspects of living donor (LD) domino liver transplantation (DLT) in maple syrup urine disease (MSUD) are limited. The largest published series includes only 3 cases. One great challenge of this procedure is to ensure adequate vascular stumps for the LD, the MSUD patient, and the recipient of the domino graft. Here, we describe our experience in 11 cases of LD-DLT in MSUD, highlighting the technical aspects of LD-DLT.

METHODS

From September 2012 to September 2017, 11 patients with MSUD underwent LD liver transplantation at our institution, and MSUD livers were used as domino grafts in 11 children.

RESULTS

(1) MSUD patients: 10 patients received a left lateral segment. The donor's left hepatic vein (HV) was anastomosed to the confluence of the recipient's 3 HVs. No vascular grafts (VG) were required for portal vein (PV) anastomosis. Single arterial anastomosis was performed with microsurgery in 10 of 11 patients. (2) MSUD graft recipients: In 8 cases, HV reconstruction was performed between the graft's HV confluence and the recipient's HV confluence, and in 3 cases, a vena cava triangulation was necessary; 6 MSUD grafts required HV venoplasty. No VG were needed for HV reconstruction. VG were used for PV reconstruction in 3 cases due to sclerotic PV. In 2 cases, double arterial anastomoses were performed in the MSUD liver. All patients remain alive and well.

CONCLUSIONS

Living donor liver transplantation followed by DLT for MSUD is a complex procedure and demands technical refinement. Special attention must be paid to vascular reconstruction.

Domino liver transplantation for select metabolic disorders: Expanding the living donor pool

Domino liver transplantation (DLT) involves transplanting liver from a patient with metabolic disease into a patient with end-stage liver disease with the expectation that the recipient will not develop the metabolic syndrome or the recurrent syndrome will have minimal affect. The domino donor gets a deceased donor or a segment of live-donor liver through the deceased donor organ allocation system. Waitlist mortality for the domino recipient exceeds morbidity associated with getting the donor disease. Between 2015 and 2017, four patients with three metabolic disorders at UPMC Children's Hospital of Pittsburgh underwent DLT with domino allografts from maple syrup urine disease (MSUD) patients. These included patients with propionic acidemia (PA) (n = 1), Crigler-Najjar (CN) syndrome type-1 (n = 2), and carbamoyl phosphate synthetase deficiency (CPSD) (n = 1). Mean follow-up was 1.6 years (range 1.1-2.1 years). Total bilirubin levels normalized postoperatively in both CN patients and they maintain normal allograft function. The PA patient had normal to minimal elevations of isoleucine and leucine, and no other abnormalities on low protein diet supplemented with a low methionine and valine free formula. No metabolic crises have occurred. The patient with CPSD takes normal baby food. No elevation in ammonia levels have been observed in any of the patients. DLT for a select group of metabolic diseases alleviated the recipients of their metabolic defect with minimal evidence of transferrable-branched chain amino acid elevations or clinical MSUD despite increased protein intake. DLT using allografts with MSUD expands the live donor liver pool and should be considered for select metabolic diseases that may have a different enzymatic deficiency.

A Worldwide Survey of Live Liver Donor Selection Policies at 24 Centers With a Combined Experience of 19 009 Adult Living Donor Liver Transplants

BACKGROUND

Although surgical technique in living donor liver transplantation (LDLT) has evolved with a focus on donor safety and recipient challenges, the donor selection criteria remain considerably disparate.

METHODS

A questionnaire on donor selection was sent to 41 centers worldwide. 24 centers with a combined experience of 19 009 LDLTs responded.

RESULTS

Centers were categorized into predominantly LDLT (18) or deceased donor liver transplantation (6), and high- (10) or low-volume (14) centers. At most centers, the minimum acceptable graft-to-recipient weight ratio was 0.7 or less (67%), and remnant was 30% (75%). The median upper limit of donor age was 60 years and body mass index of 33 kg/m. At 63% centers, age influenced the upper limit of body mass index inversely. Majority preferred aspartate transaminase and alanine transaminase less than 50 IU/mL. Most accepted donors with nondebilitating mild mental or physical disability and rejected donors with treated coronary artery disease, cerebrovascular accident and nonbrain, nonskin primary malignancies. Opinions were divided about previous psychiatric illness, substance abuse and abdominal surgery. Most performed selective liver biopsy, commonly for steatosis, raised transaminases and 1 or more features of metabolic syndrome. On biopsy, all considered macrovesicular and 50% considered microvesicular steatosis important. Nearly all (92%) rejected donors for early fibrosis, and minority for nonspecific granuloma or mild inflammation. Most anatomical anomalies except portal vein type D/E were acceptable at high-volume centers. There was no standard policy for preoperative or peroperative cholangiogram.

CONCLUSIONS

This first large live liver donor survey provides insight into donor selection practices that may aid standardization between centers, with potential expansion of the donor pool without compromising safety.

Ethical Analysis and Policy Recommendations Regarding Domino Liver Transplantation

Due to the widening gap between supply and demand, patients who need a liver transplant due to metabolic disease may be asked to serve as domino liver donors-to have their native liver transplanted into another candidate. We here analyze the ethical problems surrounding informed consent for the implant and explant procedures in transplant candidates who will serve as domino donors, using the case of a child with maple syrup urine disease. We discuss the need for 2 distinct consent processes separated in time to ensure that potential domino donors (or their surrogates) give a truly voluntary consent. We propose a Domino Donor Advocate-based on the concept of the independent living donor advocate to help the patient and/or his or her surrogates consider the risks, benefits and alternatives. Finally, we evaluate the Organ Procurement and Transplantation Network policy regarding "therapeutic organ donation" and propose several modifications to ensure that the decision by the potential domino donor (and/or his or her surrogate) is voluntary and informed.

Domino Liver Transplantation: Where are we Now?

BACKGROUND

Domino transplant occurs when a recipient explanted graft is used for a second recipient.

INTRODUCTION

The first experience came from thoracic surgery by the observation that many patients during heart-lung transplantation actually showed a functional heart that could be employed in other subjects with a good result.

RESULTS

This concept was then extended to the field of liver transplantation. At present, some patients transplanted for an inborn metabolic disease may be considered as excellent domino liver donors.

CONCLUSION

The results, limitations, clinical challenges and the donor and recipient features of domino liver transplantation are discussed in this manuscript.

Outcomes of domino liver transplantation compared to deceased donor liver transplantation: a propensity-matching approach

Domino liver transplantation (DLT) utilizes the explanted liver of one liver transplant recipient as a donor graft in another patient. While there may be unique risks associated with DLT, it is unclear if DLT has less favorable long-term outcomes than deceased donor liver transplantation (DDLT). We used a propensity score matching approach to compare the outcomes of DLT recipients to DDLT recipients. The United Network for Organ Sharing (UNOS) registry was queried for patients undergoing DLT or DDLT in 2002-2016. Each DLT recipient was matched to a unique DDLT recipient to compare mortality and graft failure. There were 126 DLT and 62 835 DDLT recipients meeting inclusion criteria. After propensity score matching on recipient pre-transplant characteristics, 123 DLT cases were matched to DDLT controls from the same UNOS region. On stratified Cox proportional hazards regression, DLT incurred no increase in the hazard of mortality [hazard ratio (HR) = 1.4; 95% confidence interval (CI): 0.8, 2.7; P = 0.265] or graft failure (HR = 1.2; 95% CI: 0.7, 2.1; P = 0.556) compared to DDLT. Using a large national registry, a propensity-matched analysis found no increased risk of mortality or graft failure associated with DLT compared to DDLT.

Current strategies for the treatment of inborn errors of metabolism

Inborn errors of metabolism (IEMs) are a large group of inherited disorders characterized by disruption of metabolic pathways due to deficient enzymes, cofactors, or transporters. The rapid advances in the understanding of the molecular pathophysiology of many IEMs, have led to significant progress in the development of many new treatments. The institution and continued expansion of newborn screening provide the opportunity for early treatment, leading to reduced morbidity and mortality. This review provides an overview of the diverse therapeutic approaches and recent advances in the treatment of IEMs that focus on the basic principles of reducing substrate accumulation, replacing or enhancing absent or reduced enzyme or cofactor, and supplementing product deficiency. In addition, the challenges and obstacles of current treatment modalities and future treatment perspectives are reviewed and discussed.