Renal Function Recovery in Children Undergoing Combined Liver Kidney Transplants

Current status and future directions of liver transplantation for metabolic liver disease in children

Orthotopic liver transplantation (OLT) in the care of children with inborn errors of metabolism (IEM) is well established and represent the second most common indication for pediatric liver transplantation in most centers worldwide, behind biliary atresia. OLT offers cure of disease when a metabolic defect is confined to the liver, but may still be transformative on a patient's quality of life reducing the chance of metabolic crises causing neurological damage in children be with extrahepatic involvement and no "functional cure." Outcomes post-OLT for inborn errors of metabolism are generally excellent. However, this benefit must be balanced with consideration of a composite risk of morbidity, and commitment to a lifetime of post-transplant chronic disease management. An increasing number of transplant referrals for children with IEM has contributed to strain on graft access in many parts of the world. Pragmatic evaluation of IEM referrals is essential, particularly pertinent in cases where progression of extra-hepatic disease is anticipated, with long-term outcome expected to be poor. Decision to proceed with liver transplantation is highly individualized based on the child's dynamic risk-benefit profile, their family unit, and their treating multidisciplinary team. Also to be considered is the chance of future treatments, such as gene therapies, emerging in the medium term.

Short-Term Outcome of Isolated Kidney Transplantation in Children with Autosomal Recessive Polycystic Kidney Disease: A Case Series and Literature Review

Autosomal recessive polycystic kidney disease (ARPKD) is often associated with hepatobiliary disease in the form of hepatic fibrosis and/or Caroli disease. Combined liver-kidney transplantation (CLKT) is a transplant modality of choice in children with both end-stage renal disease (ESRD) and severe hepatic disease. However, there is no consensus on whether children with ARPKD-associated ESRD without severe hepatic disease can be treated with isolated kidney transplantation (KT) without the need for CLKT. We retrospectively studied the efficacy of isolated KT in children with ARPKD without severe hepatic disease, and followed the course of hepatic disease post KT. This is a single-center study of three children with ARPKD and ESRD who underwent isolated KT. None of them had severe hepatic disease at the time of KT. All children were clinically diagnosed with ARPKD in the immediate postnatal period. All had hepatic fibrosis of varying degrees and two had intrahepatic biliary duct (IHBD) dilatation. None had gastrointestinal (GI) bleed, portal hypertension or cholangitis. Two children had preemptive KT. Pre-transplant unilateral or bilateral native nephrectomy were performed for two children, and one underwent unilateral native nephrectomy at the time of KT. The median creatinine clearance at a median post-KT follow-up of 24 months was 60.3 mL/min/1.73 m2. The two-year graft and patient survival were both 100%. Post KT, all three patients continued to demonstrate evidence of hepatic fibrosis and IHBD on sonogram; however, none of them were either evaluated for or required liver transplantation given normal synthetic liver function and absence of portal hypertension or other severe hepatobiliary disease. There were no adverse events observed such as cholangitis, GI bleed, or multiorgan failure. Hence, an excellent short-term graft and patient survival was demonstrated in this study of children with ARPKD and mild to moderate hepatic disease who received isolated KT. Long-term follow-up and larger studies are important to assess the efficacy of isolated KT in this subset of children with ARPKD.

Transplantation outcomes in patients with primary hyperoxaluria: a systematic review

BACKGROUND

Primary hyperoxaluria type 1 (PH1) is characterized by hepatic overproduction of oxalate and often results in kidney failure. Liver-kidney transplantation is recommended, either combined (CLKT) or sequentially performed (SLKT). The merits of SLKT and the place of an isolated kidney transplant (KT) in selected patients are unsettled. We systematically reviewed the literature focusing on patient and graft survival rates in relation to the chosen transplant strategy.

METHODS

We searched MEDLINE and Embase using a broad search string, consisting of the terms 'transplantation' and 'hyperoxaluria'. Studies reporting on at least four transplanted patients were selected for quality assessment and data extraction.

RESULTS

We found 51 observational studies from 1975 to 2020, covering 756 CLKT, 405 KT and 89 SLKT, and 51 pre-emptive liver transplantations (PLT). Meta-analysis was impossible due to reported survival probabilities with varying follow-up. Two individual high-quality studies showed an evident kidney graft survival advantage for CLKT versus KT (87% vs. 14% at 15 years, p<0.05) with adjusted HR for graft failure of 0.14 (95% confidence interval: 0.05-0.41), while patient survival was similar. Three other high-quality studies reported 5-year kidney graft survival rates of 48-89% for CLKT and 14-45% for KT. PLT and SLKT yielded 1-year patient and graft survival rates up to 100% in small cohorts.

CONCLUSIONS

Our study suggests that CLKT leads to superior kidney graft survival compared to KT. However, evidence for merits of SLKT or for KT in pyridoxine-responsive patients was scarce, which warrants further studies, ideally using data from a large international registry.

Clinical analysis of 13 children with primary hyperoxaluria type 1

A retrospective statistical analysis of primary hyperoxaluria type 1 (PH1) in children from June 2016 to May 2019 was carried out to discover its clinical and molecular biological characteristics. Patients were divided into two groups (infant and noninfant) according to clinic type. There were 13 pediatric patients (male:female = 6:7) with PH1 in the cohort from 11 families (four of which were biological siblings from two families), whose median age of symptom onset was 12 months and median confirmed diagnosis age was 14 months. Infant type (6 patients) was the most common type. The infant type mortality rate (100%) was higher than the noninfant (14.3%) (p = 0.029). The incidence of renal failure in infant patients was 67%, while the noninfant was 14.3%. 8 of 10 patients with nephrocalcinosis (NC) (76.92%, 10/13) were diagnosed by radiological imaging examinations, including X-ray (3 patients), CT (4 patients) and MRI (1 patient). NC was an independent risk factor for renal insufficiency [OR 3.33, 95% CI (0.7-1.2)], p < 0.05). Nine types of AGXT gene mutations were found; 1 type, c.190A > T, were first reported here. The most common AGXT gene mutation was c.679_680del, which occurred in exon 6 (5 patients). The infant type is the most common type of pediatric PH, with a relatively higher ratio of renal failure at symptom onset and poor prognosis. NC is an independent risk factor leading to renal failure, and radiological imaging examination is recommended for patients with abnormal ultrasound examination to identify NC. AGXT gene detection is important for the diagnosis and treatment of PH1 in children.

Impact on the hepatic flow velocity after pediatric combined liver-kidney transplantation compared to isolated pediatric liver transplantation-A matched-pair analysis

BACKGROUND

Combined liver-kidney transplantation (CLKT) in children is still a rarely performed procedure. Our aim was to analyze the effect of the simultaneous transplantation of the kidney in pediatric CLKT on the liver graft flow velocity, and vascular complications compared to singular liver transplantation (LTX) in children.

METHODS

All pediatric CLKT performed at our institution from 1998 to 2016 were matched with singular LTX and retrospectively analyzed.

RESULTS

Overall 30 CLKT were performed in 28 children (median age 8 years, range 1-16) and matched with 30 children undergoing singular LTX (median age 7.9 years, range 1-16). No significant differences were found concerning the systolic peak flow velocity of the hepatic artery (HA) or the resistance index (RI). Vascular complications of the hepatic vessels occurred in 16.7% (CLKT) and 6.7% (LTX). The 1-/5- and 10-year patient survival was 93.3%/93.3% and 93.3% (CLKT) and 100%/100% and 92.9% (LTX). 1-/5-and 10-year liver graft survival was 76.7%/73.2% and 73.2% (CLKT) and 84.4%/75.9% and 69.6% (LTX).

CONCLUSION

The simultaneous transplantation of the kidney in CLKT had no negative impact on hepatic flow velocity or vascular complications. Frequent Doppler ultrasound examinations, accurate volume management, and avoidance of abdominal pressure might be an explanation for the results and an excellent graft- and patient survival.

Evolving Trends in Liver Transplant for Metabolic Liver Disease in the United States

Indications for liver transplantation (LT) in metabolic disease are evolving. We reviewed the US experience with primary LT for metabolic disease in the Scientific Registry for Transplant Recipients (October 1987 to June 2017) to determine the following: temporal changes in indications, longterm outcomes, and factors predicting survival. Patients were grouped by the presence of structural liver disease (SLD) and whether the defect was confined to the liver. There were 5996 patients who underwent LT for metabolic disease, 2354 (39.3%) being children. LT for metabolic disease increased in children but not in adults. Children experienced a 6-fold increase in LT for metabolic disease without SLD. Indications for LT remained stable in adults. Living donor liver transplantation increased between era 1 and era 3 from 5.6% to 7.6% in children and 0% to 4.5% in adults. Patient and graft survival improved with time. The latest 5-year patient survival rates were 94.5% and 81.5% in children and adults, respectively. Outcomes were worse in adults and in those with extrahepatic disease (P < 0.01), whereas SLD did not affect outcomes. Survival improved with younger age at LT until age <2 years. On multivariate analysis, diagnostic category, inpatient status, age at LT, and transplant era significantly predicted outcomes in all ages with male sex predicting survival in childhood only. Children without structural disease were less likely to die awaiting LT and had improved post-LT survival compared with children with chronic liver disease. In conclusion, LT for metabolic disease is increasingly used for phenotypic correction in children; extrahepatic manifestations significantly impact survival at all ages; where indicated, transplantation should not be unnecessarily delayed; and the development of new allocation models may be required.

Successful long-term outcome of pediatric liver-kidney transplantation: a single-center study

INTRODUCTION

Liver-kidney transplantation is a rare procedure in children, with just ten to 30 cases performed annually worldwide. The main indications are autosomal recessive polycystic liver-kidney disease and primary hyperoxaluria. This study aimed to report outcomes of liver-kidney transplantation in a cohort of pediatric patients.

METHODS

We retrospectively analyzed all pediatric liver-kidney transplantations performed in our center between September 2000 and August 2015. Patient data were obtained by reviewing inpatient and outpatient medical records and our transplant database.

RESULTS

A total of 14 liver-kidney transplants were performed during the study period, with a median patient age and weight at transplant of 144.4 months (131.0-147.7) and 27.3 kg (12.0-45.1), respectively. The indications for liver-kidney transplants were autosomal recessive polycystic liver-kidney disease (8/14), primary hyperoxaluria -1 (5/14), and idiopathic portal hypertension with end-stage renal disease (1/14). Median time on waiting list was 8.5 months (5.7-17.3). All but two liver-kidney transplants were performed simultaneously. Patients with primary hyperoxaluria-1 tended to present a delayed recovery of renal function compared with patients transplanted for other indications (62.5 vs 6.5 days, respectively, P 0.076). Patients with liver-kidney transplants tended to present a lower risk of acute kidney rejection than patients transplanted with an isolated kidney transplant (7.2% vs 32.7%, respectively; P < 0.07). Patient and graft survival at 1, 3, and 5 years were 100%, 91.7%, 91.7%, and 91.7%, 83.3%, 83.3%, respectively. No other grafts were lost.

CONCLUSION

Long-term results of liver-kidney transplants in children are encouraging, being comparable with those obtained in isolated liver transplantation.

Sequential kidney-liver transplantation from the same living donor for lecithin cholesterol acyl transferase deficiency

BACKGROUND

Lecithin cholesterol acyl transferase (LCAT) deficiency is a rare autosomal recessive disorder of lipoprotein metabolism that results in end-stage renal disease (ESRD) necessitating transplantation. As LCAT is produced in the liver, combined kidney and liver transplantation was proposed to cure the clinical syndrome of LCAT deficiency.

METHODS

A 29-year-old male with ESRD secondary to LCAT deficiency underwent a sequential kidney-liver transplantation from the same living donor (LD). One year following the kidney transplant, auxiliary partial orthotopic liver transplant (APOLT) of a left lateral segment from the same donor was performed.

RESULTS

At 5 years follow-up, there have been no major complications, readmissions, or rejection episodes. Serum lipid abnormalities recurred within the first year, but liver and kidney allograft function remains intact.

CONCLUSION

Few cases of sequential transplantation from the same LD have been performed in adults. This is the first APOLT and multi-organ transplant performed for LCAT deficiency. Sequential organ transplant from the same LD for ESRD secondary to a metabolic disorder of the liver is feasible in adults and should be further investigated.

Outcomes of combined liver-kidney transplantation in children: analysis of the scientific registry of transplant recipients

Combined liver-kidney transplantation (CLKT) in children is uncommon and outcomes have not been well defined. Using the Scientific Registry of Transplant Recipients, data were analyzed on 152 primary pediatric CLKTs performed from October 1987 to February 2011, to determine their outcome in the largest series reported to date. Patient survival was 86.8%, 82.1% and 78.9% at 1, 5 and 10 years, liver graft survival was 81.9%, 76.5% and 72.6%, and kidney graft survival was 83.4%, 76.5% and 66.8%. By way of comparison, the Registry was queried for pediatric patient survival following isolated liver transplantation (LT) during the same time frame: 86.7%, 81.2% and 77.4% and following isolated kidney transplant (KT): 98.2%, 95.4% and 90% at 1, 5 and 10 years. In patients having undergone CLKT, primary hyperoxaluria was associated with reduced patient (p = 0.01), liver graft (p = 0.01) and kidney graft survival (p = 0.01). Furthermore, graft outcome following CLKT improved over the past decade (p = 0.04 for liver, p = 0.02 for kidney), but this did not translate into improved patient outcome (p = 0.2). All in all, our results confirmed that survival following LT was less than following KT, and that CLKT offered similar patient survival to isolated LT.

Combined liver and kidney transplantation in children

Simultaneous combined liver-kidney transplantation (CLKT) is a rare operation in pediatric patients so that annually only 10-30 operations are performed worldwide. The main indications for CLKT are primary hyperoxaluria type 1 and autosomal recessive polycystic kidney disease. In addition, CLKT is indicated in individual patients with metabolic or cirrhotic liver diseases and end-stage kidney disease. The surgery and immediate post-operative management of CLKT remain challenging in infants and small children. The patients should be operated on before they become severely ill or develop major systemic manifestations of their metabolic disorder. The liver allograft is immunologically protective of the kidney graft in simultaneous CLKT, often resulting in well-preserved kidney function. The long-term outcome after CLKT is nowadays comparable to that of isolated liver and kidney transplantations.

Combined liver-kidney transplantation for children with autosomal recessive polycystic kidney disease (ARPKD): indication and outcome

In ARPKD, mutations in the PKHD1 gene lead to remodeling of the kidneys and liver. These may result in progressive liver fibrosis with portal hypertension requiring combined liver and kidney transplantation (CLKT). There is currently no consensus on the indication for CLKT and data on long-term outcomes are scarce. We analyzed in detail the pretransplant liver symptomatology, laboratory and ultrasound data, histological studies, and genotypes in eight patients undergoing CLKT. The median age was 10.1 years (range 1.7-16) and median follow-up was 4.6 years (range 1.1-8.9). All patients had clinical signs of portal hypertension and abnormal ultrasound findings. Congenital hepatic fibrosis was present in all pretransplant biopsies (6 out of 8 patients) and in all explanted livers. All patients survived; liver and kidney graft survival was 72% and 88%, respectively. Liver and kidney function were stable in all patients with a median eGFR of 70 ml/min/1.73 m² (range 45-108 ml/min/1.73 m²). Height-SDS improved significantly after 12, 24, and 36 months (P = 0.016, 0.022 and 0.018 respectively). The indication for CLKT remains challenging and controversial. A favorable outcome for patients with ARPKD can be achieved by using the degree of portal hypertension, longitudinal ultrasound examinations, and preoperative liver histology as parameters for CLKT.

Surgical aspects and outcome of combined liver and kidney transplantation in children

In children with renal insufficiency and accompanying or underlying liver disease, combined liver and kidney transplantations (CLKT) are indicated. However, because of the rare indications, the number of paediatric CLKT is low. Our aim was to analyse CLKT in children with special regard to surgical aspects and outcome. All paediatric CLKT performed at our institution between 1998 and 2009 were retrospectively analysed. Between 1998 and 2009, 15 CLKT were performed in 14 paediatric patients (median age 8 years, range 1-16 years). The indications for CLKT were autosomal recessive polycystic kidney disease (n = 7), primary hyperoxaluria type 1 (n = 7) and retransplantation because of primary liver nonfunction (n = 1). In the postoperative course, six patients showed bleeding complications, thereof three patients needed operative revision for intra-abdominal bleeding. Eight of 15 patients (53%) needed dialysis. The 1- and 5-year patient survival was 100%; and 1- and 5-year graft survival was 80% for the liver and 93% for the kidney allograft. A number of different complications, especially secondary haemorrhage have to be anticipated after CLKT, requiring a timely and interdisciplinary treatment approach. With this management, our patients showed an excellent graft and patient survival.

Paediatric liver transplantation for metabolic disorders. Part 1: Liver-based metabolic disorders without liver lesions

Liver-based metabolic disorders account for 10 to 15% of the indications for paediatric liver transplantation. In the last three decades, important progress has been made in the understanding of these diseases, and new therapies have emerged. Concomitantly, medical and surgical innovations have lead to improved results of paediatric liver transplantation, patient survival nowadays exceeding 80% 10-year after surgery with close to normal quality of life in most survivors. This review is a practical update on medical therapy, indications and results of liver transplantation, and potential future therapies, for the main liver-based metabolic disorders in which paediatric liver transplantation may be considered. Part 1 focuses on metabolic based liver disorders without liver lesions, and part 2 on metabolic liver diseases with liver lesions.

Liver transplantation for inherited metabolic disorders of the liver

PURPOSE OF REVIEW

Liver transplantation is curative, life saving or both for a range of inherited diseases affecting the liver. Indications, timing and outcome of transplantation for these diseases are the focus of this review.

RECENT FINDINGS

Liver transplant represents a mode of gene replacement therapy for several disorders, including Wilson disease, hemochromatosis, tyrosinemia, urea cycle defects and hypercholesterolemia in which the primary defect residing in the liver results in hepatic complications or severe extrahepatic disease. Liver transplant is also an important therapeutic modality in multisystemic genetic disorders with major hepatic disease such as glycogen storage disease types I, III and IV and porphyria. For familial amyloidosis and primary hyperoxaluria, liver replacement eliminates the source of the injurious products that results in extrahepatic disease. Innovations in medical and surgical management of these patients have led to improved outcomes providing an important benchmark for future gene therapy of these disorders.

SUMMARY

Recent developments have refined the indications for liver transplant in the treatment of inherited metabolic diseases. The full potential of liver transplant in these disorders can be harnessed by careful patient selection, optimizing timing and perioperative metabolic management of these patients.

Pre-emptive liver transplantation for primary hyperoxaluria (PH-I) arrests long-term renal function deterioration

BACKGROUND

Primary hyperoxaluria-I (PH-I) is a serious metabolic disease resulting in end-stage renal disease. Pre-emptive liver transplantation (PLT) for PH-I is an option for children with early diagnosis. There is still little information on its effect on long-term renal function in this situation.

METHODS

Long-term assessment of renal function was conducted using Schwartz's formula (estimated glomerular filtration rate-eGFR) in four children (Group A) undergoing PLT between 2002 and 2008, and a comparison was done with eight gender- and sex-matched controls (Group B) having liver transplantation for other indications.

RESULTS

All patients received a liver graft from a deceased donor. Median follow-up for the two groups was 64 and 94 months, respectively. One child in Group A underwent re-transplantation due to hepatic artery thrombosis, while acute rejection was seen in one. A significant difference was seen in eGFR at transplant (81 vs 148 mL/min/1.73 m(2)) with greater functional impairment seen in the study population. In Group A, renal function reduced by 21 and 11% compared with 37 and 35% in Group B at 12 and 24 months, respectively. At 2 years post-transplantation, there was no significant difference in eGFR between the two groups (72 vs 100 mL/min/1.73 m(2), respectively; P = 0.06).

CONCLUSIONS

Renal function remains relatively stable following pre-emptive LTx for PH-I. With early diagnosis of PH-I, isolated liver transplantation may prevent progression to end-stage renal disease and the need for renal transplantation.