Four hundred thirty consecutive pediatric living donor liver transplants: variables associated with posttransplant patient and graft survival

Living Donor Whole and Partial Liver Grafts, Deceased Donor Whole Liver and SPLIT: Outcome Comparison

BACKGROUND

Currently, graft options for pediatric liver transplantation (PLT) include whole (WL) and partial (P) grafts, in the form of either deceased donor transplantation (DD) or living donor liver transplantation (LD). WL transplants from LD are commonly referred to as domino LT. The objective of this manuscript is to compare the outcomes of PLT performed with each of the available graft options.

METHODS

Retrospective cohort study from Jan. 2010 to Dec. 2022. The variables included data on the recipients' preoperative clinical status, intraoperative technical aspects, post-operative complications, and survival studies. There were 4 groups: SPLIT (17), DD-WL (55), LD-WL (824), and LD-P (22).

RESULTS

The median age and BW of the recipients was smaller in SPLIT, LD-P, and LD-WL compared to DDT-WL groups. HVOO (HR 15.87, 95% CI 1.89-133.06, P = 0.01), retransplantation (HR 7.94, 95% CI 2.63-24.02, P < 0.01), and malignancies (HR 3.08, 95% CI 1.29-7.37, P = 0.01) were independently associated with decreased patient survival. HAT (HR 27.54, 95% CI 10.44-72.68, P < 0.01) and malignancies (HR 2.42, 95% CI 1.10-5.34, P = 0.03) increased the risk of graft loss. The overall survival in this series was 91.4% (mean follow-up of 74.3 months). Patient and graft survival were not different among groups.

CONCLUSION

HAT and malignancies were associated with reduced graft survival. Whole liver from living donors with MSUD presented 100% patient survival at 120 months. Even without statistical differences in survival among the studied groups, LD-P and LD-WL recipients presented a trend towards better outcomes.

LEVEL OF EVIDENCE

LEVEL III.

Treatment Strategies for Bile Leak Following Pediatric Liver Transplantation

There are no standard management protocols for the treatment of bile leak (BL) after liver transplantation. The objective of this study is to describe treatment options for BL after pediatric LT.

METHODS

Retrospective analysis (January 2010-March 2023).

VARIABLES STUDIED

preoperative data, status at diagnosis, and postoperative outcome. Four groups: observation (n = 9), percutaneous transhepatic cholangiography (PTC, n = 38), ERCP (2), and surgery (n = 27).

RESULTS

Nine hundred and thirty-one pediatric liver transplantation (859 LDLT and 72 DDT); 78 (8.3%) patients had BL, all in LDLT. The median (IQR) peritoneal bilirubin (PB) level and fluid-to-serum bilirubin ratio (FSBR) at diagnosis was 14.40 mg/dL (8.5-29), and 10.7 (4.1-23.7). Patients who required surgery for treatment underwent the procedure earlier, at a median of 14 days (IQR: 7-19) versus 22 days for PTC (IQR: 15-27, p = 0.002). PB and FSBR were significantly lower in the observation group. In 11 cases, conservative management had resolution of the BL in an average time of 35 days, and 38 patients underwent PTC in a median time of 22 days (15-27). Twenty-seven (34.6%) patients were reoperated as initial treatment for BL in a median time of 17 days (1-108 days); 25 (33%) patients evolved with biliary stricture, 5 (18.5%) after surgery, and 20 (52.6%) after PTC (p = 0.01).

CONCLUSION

Patients with BL who were observed presented significantly lower levels of PB and FSBR versus those who underwent PTC or surgery. Patients treated with PTC presented higher rates of biliary stricture during the follow-up.

Are the Post-transplant Outcomes of Kasai's Early Failure and Late Failure Comparable to the Primary Liver Transplantation?

It is uncertain whether prior Kasai procedures negatively impact the outcomes of liver transplantation (LT). The prior meta-analysis did not distinguish between Kasai early failure (K-EF) and late failure (K-LF). Numerous studies have been recently published; therefore, we perform a systematic review and meta-analysis. We searched PubMed and Embase databases to identify studies comparing the outcomes of biliary atresia (BA) patients undergoing primary LT versus patients with prior Kasai procedures. Subgroup analysis was done at the time of Kasai failure (early vs. late). Twenty-five studies comprising 6,408 patients receiving LT were included in the analysis. We found a statistically significant increase in one-year graft survival in K-LF versus primary liver transplant (pLT) (P = 0.0003). One-year patient survival was also increased in K-LF, although not statistically significant (P = 0.09). No difference in the one- and five-year graft and patient survival, reoperation rate, infection, and biliary complication was seen in pLT vs overall prior Kasai (K-EF and K-LF). These results suggest that prior kasai procedure does not negatively impact the outcome of LT. In addition, BA patients with prior Kasai undergoing LT later in life tend to perform better than primary liver transplants.

Treatment of maple syrup urine disease: Benefits, risks, and challenges of liver transplantation

Maple syrup urine disease (MSUD) is caused by a deficiency in the activity of the branched-chain α-ketoacid dehydrogenase (BCKD) complex, promoting the accumulation of the branched-chain amino acids (BCAA) leucine, isoleucine, and valine, as well as their respective α-keto acids. MSUD is an autosomal recessive hereditary metabolic disorder characterized by ketoacidosis, ataxia, coma, and mental and psychomotor retardation. The mechanisms involved in the brain damage caused by MSUD are not fully understood. Early diagnosis and treatment, as well as proper control of metabolic decompensation crises, are crucial for patients' survival and for a better prognosis. The recommended treatment consists of a high-calorie diet with restricted protein intake and specific formulas containing essential amino acids, except those accumulated in MSUD. This treatment will be maintained throughout life, being adjusted according to the patients' nutritional needs and BCAA concentration. Because dietary treatment may not be sufficient to prevent neurological damage in MSUD patients, other therapeutic strategies have been studied, including liver transplantation. With transplantation, it is possible to obtain an increase of about 10% of the normal BCKD in the body, an amount sufficient to maintain amino acid homeostasis and reduce metabolic decompensation crises. However, the experience related to this practice is very limited when considering the shortage of liver for transplantation and the risks related to the surgical procedure and immunosuppression. Thus, the purpose of this review is to survey the benefits, risks, and challenges of liver transplantation in the treatment of MSUD.

Intra-Abdominal Hypertension and Compartment Syndrome after Pediatric Liver Transplantation: Incidence, Risk Factors and Outcome

In pediatric liver transplantation (pLT), the risk for the manifestation and relevance of intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) is high. This observational study aimed to evaluate the incidence, relevance and risk factors for IAH and ACS by monitoring the intra-abdominal pressure (IAP), macro- and microcirculation (near-infrared spectroscopy (NIRS)), clinical and laboratory status and outcomes of 27 patients (16 female) after pLT (median age at pLT 35 months). Of the patients, 85% developed an elevated IAP, most of them mild. However, 17% achieved IAH° 3, 13% achieved IAH° 4 and 63% developed ACS. A multiple linear regression analysis identified aortal hepatic artery anastomosis and cold ischemia time (CIT) as risk factors for increased IAP and longer CIT and staged abdominal wall closure for ACS. ACS patients had significantly longer mechanical ventilation (p = 0.004) and LOS-PICU (p = 0.003). No significant correlation between NIRS or biliary complications and IAH or ACS could be shown. IAH and ACS after pLT were frequent. NIRS or grade of IAH alone should not be used for monitoring. A longer CIT is an important risk factor for higher IAP and ACS. Therefore, approaches such as the ex vivo machine perfusion of donor organs, reducing CIT effects on them, have great potential. Our study provides important basics for studying such approaches.

The impact of low recipient weight [≤ 7kg] on long-term outcomes in 1078 pediatric living donor liver transplantations

BACKGROUND

infants who require liver transplantation represent a treatment challenge because chronic liver disease at this early age affects the child's growth and development during a critical phase. The aim is to compare demographics, operative data, and long-term outcomes according to recipient weight at the time of LDLT.

METHODS

This retrospective study included primary LDLT analyzed in 2 groups: BW ≤ 7 kg (n = 322) and BW > 7 kg (n = 756). A historical comparison between periods was also investigated.

RESULTS

BW ≤ 7 kg had significantly lower height/age and weight/age z-scores, with median PELD score of 19. Transfusion rates were higher in the BW ≤ 7 kg group (30.9 ml/kg versus 15.5 ml/kg, P < 0.001). Higher frequencies of PV complications were seen in the BW ≤ 7 kg cohort. HAT and retransplantation rates were similar. Those with BW ≤ 7 kg required longer ICU and hospital stays. Patient and graft survival were similar. Patient survival in BW≤ 7 kg was significantly better in the most recent period.

CONCLUSION

Malnutrition and advanced liver disease were more frequent in BW ≤ 7 kg. Despite increased rates of PVT and longer hospital stay, patient and graft long-term survival were similar between groups.

Intestinal complications are common in patients with acquired diaphragmatic hernia after pediatric living donor liver transplantation

BACKGROUND

Acquired diaphragmatic hernia (DH) following liver transplantation (LT) is usually considered a surgical emergency. Interplay of contributing elements determines its occurrence but, in children, LT with partial liver grafts seems to be the most important causative factor.

METHODS

This retrospective study describes the clinical scenario and outcomes of 11 patients with acquired DH following LDLT.

RESULTS

During the study period, 1109 primary pediatric LDLT were performed (0.8% DH). The median age and BW of the recipients with DH at transplantation were 17 months and 11.1 kg, respectively; 63.7% of the cases had a weight/age Z-score of less than -2 at transplantation. The median interval between transplantation and diagnosis of DH was 114 days (32-538 days). A total of 6 (54.5%) of the patients had bowel obstruction due to bowel migration into the hemithorax. Ten defects were right-sided. Three patients required enterectomy and enterorrhaphy. Two patients required a new bilioenteric anastomosis, and one of them had complete necrosis of the Roux-in-Y limb. The patient with left-side DH presented gastroesophageal perforation.

CONCLUSION

Most defects necessitate primary closure as the first treatment, and recurrence is rare. The associated problems encountered, especially related to intestinal complications, can determine increased morbidity following DH repair. Early diagnosis and intervention are required for achieving better outcomes.

Undernutrition and Hypoleptinemia Modulate Alloimmunity and CMV-specific Viral Immunity in Transplantation

BACKGROUND

Immunological mechanisms linking undernutrition to infection and the alloimmune response are poorly understood in transplantation. We aimed to determine how undernutrition and hypoleptinemia impact T-cell allospecific and cytomegalovirus (CMV) viral-specific immunity in a murine model.

METHODS

Fed, fasted for 48 h (model of undernutrition), and fasted with leptin injections (leptin rescue), C57BL/6 mice received skin grafts from either C57BL/6 (syngeneic) or BALB/c (allogeneic) mice donors. Allograft rejection and survival were monitored. Fed, fasted, and leptin rescue C57BL/6 mice were inoculated with murine cytomegalovirus (mCMV). Mouse spleens were retrieved for T-cell flow cytometry analysis, mCMV DNA extraction, and quantitative polymerase chain reaction. Serum leptin levels were measured with ELISA.

RESULTS

Fasted mice had prolonged rejection-free and graft survival compared with fed mice (P = 0.0002 and P = 0.043). Leptin administration did not alter rejection-free survival or allograft failure. CD8+ central memory T cell and CD8+ effector T cell proportions were significantly lower in fasted mice receiving allogeneic skin transplants compared with fed mice (P = 0.0009 and P = 0.0015). Fasted mice had higher viral loads (P = 0.0028) and impaired mCMV-specific interferon-gamma-producing CD8+ T cells (P = 0.0007), which improved with leptin rescue (P = 0.032).

CONCLUSIONS

Undernutrition and its associated hypoleptinemia correlated with impaired allospecific and viral-specific immunities. Leptin administration decreased mCMV viral burden and increased mCMV-specific T-cell immunity, however, it did not increase rejection or worsen graft survival in complete major histocompatibility complex-mismatched skin allografts. Leptin may be a potential adjunctive therapy for CMV viremia in undernourished transplant recipients.

Impact of sarcopenia in infants with liver transplantation for biliary atresia

While sarcopenia is an important predictor of LT outcomes in adults, few studies have examined the association of sarcopenia with LT outcomes in pediatric patients. We investigated the clinical influence of sarcopenia on the post-transplant outcomes in infants with BA. To define sarcopenia in infants, the cross-sectional area of the tPMA in 93 healthy control infants was measured by computed tomography. Sarcopenia was defined as a tPMA lower than two standard deviations below the mean of healthy control infants. Eighty-nine infants with BA with a median age at LT of 7.6 months old were enrolled. The clinical characteristics and outcomes of LT were verified in the sarcopenia group (n = 21) and non-sarcopenia group (n = 68). The sarcopenia group had a significantly longer operation time and greater blood loss during LT than the non-sarcopenia group (P = .03 and 0.02). The incidence of portal vein stenosis and post-operative bloodstream infection was also significantly higher in the sarcopenia group than in the non-sarcopenia group (23.8% vs 4.4%, P = .02 and 28.6% vs 10.3%, P = .04, respectively). The total length of hospital stay did not differ significantly. The 1-year patient and graft survival rates tended to be lower in the sarcopenia group than in the non-sarcopenia group (90.5% vs 98.5%, P = .07 and 85.7% vs 97.1%, P = .05, respectively). Sarcopenia in infants with BA may be associated with the patient survival and serve as an effective marker for post-operative outcomes of LT.

Impact of hypoxemia on pediatric liver transplantation for hepatopulmonary syndrome

BACKGROUND

The treatment of choice for patients with cirrhosis and HPS is LT. The clinical manifestations associated with hypoxemia result in limitations and a poor health-related quality of life of affected patients. The present report aims to study the differences in outcomes between patients with PaO₂  < 50 mm Hg and those with PaO₂  ≥ 50 mm Hg.

METHODS

This was a retrospective study of 21 patients under 18 years of age conducted from 2001 to 2018; the patients were divided into 2 groups: G1-PaO₂  ≥ 50 mm Hg, 11 patients, and G2-PaO₂  < 50 mm Hg, 10 patients. Demographic, clinical, laboratory, and perioperative data; outcome variables; and post-transplant survival were compared between the groups.

RESULTS

In total, 2/11 (18.2%) patients in G1 and 8/10 (80%) patients in G2 required supplemental oxygen therapy at home (P = .005). Patients in G2 required prolonged MV (median 8.5 days in G2 vs 1 day in G1, P = .015) and prolonged ICU and hospital stays (P = .002 and P = .001, respectively). Oxygen weaning time was longer in G2 (median 127.5 days) than in G1 (median 3 days; P = .004). One (9.1%) patient in G1 and three (30%) patients in G2 died (P = .22). The survival at 90 months was 90.9% in G1 and 70% in G2 (P = .22).

CONCLUSION

The survival between groups was similar. Patients with very severe HPS required a longer MV time, longer ICU and hospital stays, and a longer O₂ weaning time than those with mild, moderate, or severe HPS.

METABOLIC AND NUTRITIONAL REPERCUSSIONS OF LIVER DISEASE ON CHILDREN: HOW TO MINIMIZE THEM?

Objective:

To describe the metabolic and nutritional repercussions of chronic liver disease (CLD), proposing strategies that optimize nutritional therapy in the pre- and post-liver transplantation (LT) period, in order to promote favorable clinical outcomes and adequate growth and development, respectively.

Data sources:

Bibliographic search in the PubMed, Lilacs and SciELO databases of the last 12 years, in English and Portuguese; target population: children from early childhood to adolescence; keywords in Portuguese and their correlates in English: “Liver Transplant,” “Biliary Atresia,” “Nutrition Therapy,” “Nutritional Status,” and “Child”; in addition to Boolean logics “and” and “or,” and the manual search of articles.

Data synthesis:

Malnutrition in children with CLD is a very common condition and an important risk factor for morbidity and mortality. There is an increase in energy and protein demand, as well as difficulties in the absorption of carbohydrates, lipids and micronutrients such as fat-soluble vitamins and some minerals. An increase in the supply of energy, carbohydrates and proteins and micronutrients, especially fat-soluble vitamins, iron, zinc and calcium, is suggested, except in cases of hepatic encephalopathy (this restriction is indicated for a short period).

Conclusions:

Based on metabolic changes and anthropometric and body composition monitoring, a treatment plan should be developed, following the nutritional recommendations available, in order to minimize the negative impact of malnutrition on clinical outcomes during and after LT.

The "W" Technique: A Safe and Reproducible Technique for Hepatic Artery Reconstruction in Living Donor Liver Transplantation

Background

Reconstruction of the hepatic arterial inflow can be technically demanding in living donor liver transplantation, and thrombosis can result in graft loss and mortality. We describe the safe and reproducible “W” technique to reconstruct the hepatic artery and outcomes before and after adoption of the technique in a consecutive series of liver transplants at 2 high-volume living donor liver transplant centers.

Material/Methods

Prospectively collected data were analyzed to compare the outcomes before and after introduction of a standardized “W” technique for reconstruction of the hepatic artery in 2 high-volume living donor liver transplant programs.

Results

In a consecutive series of 675 liver transplants, of which 27 were deceased donor transplants and 648 were living donor transplants, 443 transplants were performed with a standard interrupted reconstruction of the hepatic artery under loupes. These transplants were performed by a single surgeon, with an incidence of hepatic artery thrombosis of 2%. After introduction of the “W” technique, despite the arterial reconstruction being done by several surgeons in the early part of their learning curve, the incidence of hepatic artery thrombosis decreased to 0.86% in the next 232 transplants.

Conclusions

The “W” technique is a simple, easy to learn and teach technique for reconstruction of the hepatic artery without the use of the operating microscope in living donor liver transplantation.

Technical Choices in Pediatric Living Donor Liver Transplantation: The Path to Reduce Vascular Complications and Improve Survival

Pediatric living donor liver transplantation (PLDLT) is a successful therapeutic option for children with chronic and acute liver disease. After early transplant results, many technical advancements were introduced in the field to reduce the rate of complications and improve survival. The aim of this study is to present the outcomes of 975 primary PLDLTs in 3 periods: initial practice (period 1, 29 patients, January 1995 to December 1999), second period (period 2, 331 patients, January 2000 to December 2009), and third period (period 3 [P3], 615 patients, January 2010 to September 2019). Among the technical refinements introduced in P3 are the use of hyperreduced left lateral segment grafts, abdominal wall prosthetic mesh closure, double hepatic artery anastomosis, and increased use of vascular grafts for portal vein reconstruction. The outcomes included significant reductions of hepatic artery thrombosis (HAT), early portal vein thrombosis (EPVT), and retransplantation, with better patient and graft survival in P3. Additional analyses showed that the factors independently associated with worse 90-day patient survival were HAT, EPVT, and increasing Pediatric End-Stage Liver Disease score. In conclusion, the introduction of technical refinements in P3, in addition to improvements in patient care, determined a reduction in EPVT, HAT, and retransplantation. Consequently, patient and graft survival rates increased in all time points studied.

Projected 20- and 30-Year Outcomes for Pediatric Liver Transplant Recipients in the United States

BACKGROUND

Observed long-term outcomes no longer reflect the survival trajectory facing pediatric liver transplant (LT) recipients today. We aimed to use national registry data and parametric models to project 20- and 30-year post-transplant outcomes for recently transplanted pediatric LT recipients.

METHODS

We conducted a retrospective cohort study of 13,442 first-time pediatric (age <18) LT recipients using 1987 to 2018 Scientific Registry of Transplant Recipients data. We validated the proposed method (ie, to project long-term patient and graft survival using parametric survival models and short-term data) in 2 historic cohorts (1987-1996 and 1997-2006) and estimated long-term projections among patients transplanted between 2007 and 2018. Projections were stratified by raft type, recipient age, and indication for transplant.

RESULTS

Parsimonious parametric models with Weibull distribution can be applied to post-transplant data and used to project long-term outcomes for pediatric LT recipients beyond observed data. Projected 20-year patient survival for pediatric LT recipients transplanted in 2007 to 2018 was 84.0% (95% confidence interval 81.5-85.8), compared to observed 20-year survival of 72.8% and 63.6% among those transplanted in 1997 to 2006 and 1987 to 1996, respectively. Projected 30-year survival for pediatric LT recipients in 2007 to 2018 was 80.1% (75.2-82.7), compared to projected 30-year survival of 68.6% (66.1-70.9) in the 1997 to 2006 cohort and observed 30-year survival of 57.5% in the 1987 to 1996 cohort. Twenty- and 30-year patient and graft survival varied slightly by recipient age, graft type, and indication for transplant.

CONCLUSIONS

Projected long-term outcomes for recently transplanted pediatric LT recipients are excellent, reflective of substantial improvements in medical care, and informative for physician-patient education and decision making in the current era.

Donor-to-recipient weight ratio is a risk factor for hepatic artery thrombosis after whole-liver transplantation in children under 25 kg

Hepatic artery thrombosis (HAT) following pediatric liver transplantation increases morbidity and risk of graft failure. We performed a retrospective chart review of all patients who underwent deceased-donor liver transplantation from August 2002 to July 2016. Multi-organ transplant recipients were excluded. We examined the incidence of HAT at our institution and sought to identify associated donor or recipient risk factors. A total of 127 deceased-donor liver transplant patients with a median age of 1.7 years (IQR 0.67-6.7) were identified. Of those, 14 developed HAT, all weighing under 25 kg. Among 100 patients under 25 kg, whole-liver graft recipients had an odds ratio of 3.98 (95% confidence interval [CI]: 1.03, 15.34; P = .045) for developing HAT compared with split-liver graft recipients. Within the whole-liver recipient group under 25 kg, 11 patients developed HAT with a median donor-to-recipient ratio (DRWR) of 0.9 (IQR: 0.7-1.2) compared with a median DRWR of 1.4 (IQR: 1.1-1.9) for those who did not develop HAT. Multivariate analysis showed DRWR to be an independent risk factor for HAT in patients weighing under 25 kg who received whole organ grafts, with an odds ratio of 3.89 (95% CI: 1.43, 10.54; P = .008) for each 0.5 unit decrease in DRWR. Our results suggest that in recipients under 25 kg 1) split-liver grafts may have a lower rate of HAT and 2) selecting whole organ donors with a higher DRWR may decrease the incidence of HAT.

Impact of the Pediatric End-Stage Liver Disease (PELD) growth failure thresholds on mortality among pediatric liver transplant candidates

The Pediatric End-Stage Liver Disease (PELD) score is intended to determine priority for children awaiting liver transplantation. This study examines the impact of PELD's incorporation of "growth failure" as a threshold variable, defined as having weight or height <2 standard deviations below the age and gender norm (z-score <2). First, we demonstrate the "growth failure gap" created by PELD's current calculation methods, in which children have z-scores <2 but do not meet PELD's growth failure criteria and thus lose 6-7 PELD points. Second, we utilized United Network for Organ Sharing (UNOS) data to investigate the impact of this "growth failure gap." Among 3291 pediatric liver transplant candidates, 26% met PELD-defined growth failure, and 17% fell in the growth failure gap. Children in the growth failure gap had a higher risk of waitlist mortality than those without growth failure (adjusted subhazard ratio [SHR] 1.78, 95% confidence interval [95% CI] 1.05-3.02, P = .03). They also had a higher risk of posttransplant mortality (adjusted HR 1.55, 95% CI 1.03-2.32, P = .03). For children without PELD exception points (n = 1291), waitlist mortality risk nearly tripled for those in the gap (SHR 2.89, 95% CI 1.39-6.01, P = .005). Current methods for determining growth failure in PELD disadvantage candidates arbitrarily and increase their waitlist mortality risk. PELD should be revised to correct this disparity.

20- to 25-year patient and graft survival following a single pediatric liver transplant-Analysis of the United Network of Organ Sharing database: Where to go from here

To understand factors contributing to liver graft loss and patient death, we queried a national database designed to follow pediatric patients transplanted between 1987 and 1995 till adulthood. A comparison was made to a cohort transplanted between 2000 and 2014. The 5-, 10-, 15-, 20-, and 25-year patient survival and graft survival were 95.5%, 93.7%, 89.1%, 80.8%, and 73.1%, and 92.5%, 86.7%, 77.6%, 68.7%, and 62.2%, respectively. The twenty-year patient/graft survival was significantly worse in those transplanted between 5 and 17 years of age compared to those transplanted at <5 years of age (P < 0.001). For the modern era cohort, the 3-year patient survival was significantly lower in children transplanted at 16-17 years of age compared to those transplanted at <5 and 11-15 years of age (P ≤ 0.02). The 3-year graft survival was similarly lower in children transplanted at 16-17 years of age compared to those transplanted at <5, 5-10, and 11-15 years of age (P ≤ 0.001). Infection as a cause of death occurred either early or >15 years post-transplant. Chronic rejection remained the leading cause of graft loss in both cohorts and the commonest indication for retransplantation 20-25 years following primary transplant. Further research is required to identify modifiable factors contributing to development of chronic rejection.

Thrombosis prophylaxis in pediatric liver transplantation: A systematic review

AIM

To review current literature of thrombosis prophylaxis in pediatric liver transplantation (PLT) as thrombosis remains a critical complication.

METHODS

Studies were identified by electronic search of MEDLINE, EMBASE and Cochrane Library (CENTRAL) databases until March 2018. The search was supplemented by manually reviewing the references of included studies and the references of the main published systematic reviews on thrombosis and PLT. We excluded from this review case report, small case series, commentaries, conference abstracts, papers which describing less than 10 pediatric liver transplants/year and articles published before 1990. Two reviewers performed study selection independently, with disagreements solved through discussion and by the opinion of a third reviewer when necessary.

RESULTS

Nine retrospective studies were included in this review. The overall quality of studies was poor. A pooled analysis of results from studies was not possible due to the retrospective design and heterogeneity of included studies. We found an incidence of portal vein thrombosis (PVT) ranging from 2% to 10% in pediatric living donor liver transplantation (LDLT) and from 4% to 33% in pediatric deceased donor liver transplantation (DDLT). Hepatic artery thrombosis (HAT) was observed mostly in mixed LDLT and DDLT pediatric population with an incidence ranging from 0% to 29%. In most of the studies Doppler ultrasonography was used as a first line diagnostic screening for thrombosis. Four different surgical techniques for portal vein anastomosis were reported with similar efficacy in terms of PVT reduction. Reduced size liver transplant was associated with a low risk of both PVT (incidence 4%) and HAT (incidence 0%, P < 0.05). Similarly, aortic arterial anastomosis without graft interposition and microsurgical hepatic arterial reconstruction were associated with a significant reduced HAT incidence (6% and 0%, respectively). According to our inclusion and exclusion criteria, we did not find eligible studies that evaluated pharmacological prevention of thrombosis.

CONCLUSION

Poor quality retrospective studies show the use of tailored surgical strategies might be useful to reduce HAT and PVT after PLT; prospective studies are urgently needed.

Long-term outcome of liver transplantation in childhood: A study of 20-year survivors

We report the results of a study of survival, liver and kidney functions, and growth with a median follow-up of 24 years following liver transplantation in childhood. From 1988 to 1993, 128 children underwent deceased donor liver transplantation (median age: 2.5 years). Twenty-year patient and graft survival rates were 79% and 64%, respectively. Raised serum aminotransferase and/or γ-glutamyl transferase activities were present in 42% of survivors after a single transplantation. Graft histology (35 patients) showed signs of chronic rejection in 11 and biliary obstruction in 5. Mean total fibrosis scores were 4.5/9 and 3/9 in patients with abnormal and normal serum liver tests, respectively. Glomerular filtration rate was <90 mL·min^-1 in 35 survivors, including 4 in end-stage renal disease who were undergoing dialysis or had undergone renal transplantation. Median final heights were 159 cm for women and 172 cm for men; final height was below the target height in 37 patients. Twenty-year survival after childhood liver transplantation may be close to 80%, and final height is within the normal range for most patients. However, chronic kidney disease or altered liver biochemistries are present in over one third of patients, which is a matter of concern for the future.

Acquired diaphragmatic hernia in pediatrics after living donor liver transplantation: Three cases report and review of literature

RATIONALE

Diaphragmatic hernia (DH) in pediatrics following living donor liver transplantation (LDLT) has been seldom reported in the past.

PATIENT CONCERNS

We report successful diagnosis and treatment of three pediatric cases with DH secondary to LDLT, discuss the possible etiology, and review the relevant literature.

DIAGNOSES

The primary disease was biliary atresia and DH was diagnosed by computed tomography scan or x-ray of chest.

INTERVENTIONS

Laparotomy was performed successfully to repair the DH.

OUTCOMES

The respiratory and digestive function was gradually recovered in 1 to 2 weeks after repair operation. In 2 to 8 months follow-up, patients were asymptomatic without any respiratory or digestive complications.

LESSONS

DH post-LDLT should be recognized as a possible complication when a left lateral segment graft is used. Careful clinical examination and prompt surgery could minimize complications.

Living donor liver transplantation for post-Kasai biliary atresia: Analysis of pretransplant predictors of outcomes in infants

After decades of dramatic surgical innovations in pediatric living donor liver transplantation (LDLT), LDLT for biliary atresia (BA) still poses various challenges. This study reviewed our experience with LDLT for children with post-Kasai BA and evaluated outcomes and prognostic factors. From 2005 to 2016, 168 post-Kasai BA LDLT patients were enrolled and divided into 3 groups by age. Patient characteristics and perioperative data were compared. Predictors of morbidity and mortality following LDLT were analyzed in 93 infants. Outcome was relatively worse in infants than older children, with overall survival at 1 and 5 years of 94.5% and 93.2%, respectively, and graft survival at 1 and 5 years of 91.1% each. Incidence of vascular complications was not significantly higher in infants. High Pediatric End-Stage Liver Disease (PELD) score (odds ratio [OR], 3.72; 95% confidence interval [CI], 1.30-10.67; P = 0.02) and portal vein (PV) hypoplasia (OR, 3.23; 95% CI, 1.10-9.52; P = 0.03) were independent risk factors for morbidity. Low weight-for-age z score (hazard ratio, 5.76; 95% CI, 1.05-31.47; P = 0.03) was identified as a significant risk factor for mortality after LDLT, but not age or absolute body weight (BW). Infants with BW deficit had a significantly smaller PV diameter (P = 0.005), greater blood loss (P = 0.001), and higher incidence of postoperative bacteremia (P = 0.01). In conclusion, high PELD score and PV hypoplasia were independent risk factors for morbidity, and BW deficit was associated with poor survival in infants with post-Kasai BA after LDLT. However, LDLT in these infants at the earliest possible time after referral is a feasible option with excellent patient survival in an experienced center. Liver Transplantation 23 1199-1209 2017 AASLD.

Twenty Years of Experience in Pediatric Living Donor Liver Transplantation: Focus on Hepatic Artery Reconstruction, Complications, and Outcomes

BACKGROUND

Hepatic artery thrombosis (HAT) increases morbidity and mortality after liver transplantation (LT). The identification of risk factors for HAT may aid transplant teams in the development of strategies aimed at reducing HAT. This article describes the risk factors for HAT and outcomes after LT.

METHODS

This report describes a retrospective study (1995 to 2015) of primary pediatric living donor LT (LDLT). Pretransplant and technical variables were included in the study. Binary logistic regression was used for data analysis.

RESULTS

This study included 656 primary LDLT. The median age, body weight, and pediatric end-stage liver disease score at the time of transplant were 13 months, 8.4 kg and 15, respectively. Twenty-one (3.2%) patients developed HAT. Intraoperative HAT (odds ratio, 62.63; 95% confidence interval, 12.64-310.19; P < 0.001) and the use of liver grafts with a graft-to-recipient weight ratio less than 1.1% (odds ratio, 24.46; 95% confidence interval, 4.55-131.56; P < 0.001) retained statistical significance in the multivariate model. Patient and graft survivals were significantly worse in cases with HAT. The overtime trend analysis revealed a decrease in the incidence of HAT (P = 0.008) and an increase in the use of 2-arterial anastomosis (P < 0.001).

CONCLUSIONS

A graft-to-recipient weight ratio of 1.1% or less and intraoperative HAT were independently associated with HAT. Trend analysis further revealed a significant reduction in the incidence of HAT over time, as well as the increased use of 2 hepatic arteries for anastomosis during graft implantation. The double artery anastomosis may represent an extra protection to pediatric recipients undergoing LDLT.

Outcomes and technical aspects of liver retransplantation with living donors in children

Re-LT is the only recourse for patients with liver graft failure. However, survival rates after re-LT are lower than those of primary transplants. Few reports are available regarding re-LT with LDs in children. The objective of this study was to describe our cohort of patients retransplanted with LD and emphasize the technical aspects of a re-LT with LD. This is a retrospective report of a series of 18 children (<18 yr old) submitted to 20 re-LT from January 1997 to December 2013 at Hospital Sirio-Libanes and Hospital AC Camargo Cancer Center. The one- and five-yr survival for patients retransplanted with LD was 70.6% and 58.6%. Little technical modifications from a regular LD primary transplant were needed in patients retransplanted with LD. Seven (38.8%) patients presented vascular complications following re-LT and three presented biliary complications (16.6%). In conclusion, a re-LT with LD is an acceptable alternative for children who experience liver graft failure and it does not compromise the donor pool. Further experience with re-LT with LD may support this therapy.

Liver Transplantation in Brazil

Over 1700 liver transplantations (LTs) are performed annually in Brazil. In absolute terms, the country performs more LT surgeries than anywhere else in Latin America and is third worldwide. However, due to its increasing population and inadequate donor organ supply, the country averages 5-10 LTs per million population, far lower than required. There is a marked heterogeneity in organ donation and LT activity throughout the country. Access to LT in the underprivileged North, Midwest, and Northeast regions of Brazil is scarce. Major challenges for the future of LT in Brazil will be to increase organ donation and access to LT. The reduction of those geographical disparities in donation, organ procurement, and LT due to political and financial constraints is of utmost importance. Liver Transplantation 22 1254-1258 2016 AASLD.

Alternatives for vascular reconstruction in pediatric living donor liver transplantation

Many publications discuss the various strategies for vascular reconstruction (VR) in pediatric LDLT. Having knowledge of alternative techniques is helpful in planning transplants. This article presents three case reports that illustrate some of the alternative techniques for HV, PV, and HA reconstruction in pediatric LDLT. It also reviews the available alternative strategies reported for VR in pediatric LDLT. In the first case, a 13-month-old girl presented a PRETEXT III HB with invasion of the retrohepatic vena cava. An LLS graft HV was anastomosed to a DD iliac vein graft and subsequently implanted in a "standard" fashion in the recipient. In the second case, a 44-month-old boy presented with multifocal HB and portomesenteric thrombosis and the portal inflow was done through a renoportal anastomosis. In the third case, a 22-month-old child with a failed Kasai procedure had extensive HA thrombosis. The HA reconstruction was performed with an interposition of the recipient's IMV graft. The use of alternative techniques for VR in pediatric LDLT is paramount to the success of such a complex procedure. Imaging studies can help transplant surgeons outline surgical strategies and define the best technique to be used in each case.

Pediatric liver transplantation in Latin America: Where do we stand?

LT started in LA in 1968, and pediatric LT records are available starting in the 1990s. Currently, eight countries perform pediatric LT in LA. Registries by national organizations fail to report robust data on pediatric LT. The aim of this paper was to report on the pediatric LT activity in LA. Data were gathered retrospectively through information available in the national registries websites and from local centers. Of the eight countries that report pediatric LT activity, Brazil, Argentina, Mexico, and Colombia have adequate registries of the numbers of LT performed. These countries concentrate most of the activity for pediatric LT. A total of 4593 pediatric LT were reported in LA. Websites for national organizations do not provide open data on post-transplant survival rates or waiting list mortality. The information herein is based on reports by local centers. Overall, survival from select centers is similar to that reported on North American and European registries, between 80 and 90% in the first year post-transplant. In conclusion, pediatric LT activity is growing in LA, especially in Brazil and Argentina. However, the lack of an appropriate LA registry restricts the assessment of quality and therefore restricts interventions aimed at quality improvements in different regions.

Living donor liver transplantation in Brazil-current state

Currently in Brazil, living donor liver transplantation (LDLT) represents 8.5% of liver transplantation (LT), being the majority pediatric one. Up to now, according to Brazilian Organ Transplantation Association (ABTO) annual report, 2,086 procedures have been done nationwide, most of them in southeast and south regions. Based on national centers reports, biliary complication is the most common recipient postoperative complication (14.5-20.6%), followed by hepatic artery thrombosis (3.1-10.7%) and portal vein thrombosis (2.3-9.1%). Patient and graft overall 5-y survival correspond to 76% and 74%, respectively. Regarding the donor, morbidity rate ranges from 12.4% to 28.3%, with a national mortality rate of 0.14%. In conclusion, Brazilian LDLT programs enhance international experience that this is a feasible and safe procedure, as well as an excellent alternative strategy to overcome organs shortage.

Risk Factors Associated with Increased Morbidity in Living Liver Donation

Living donor liver donation (LDLD) is an alternative to cadaveric liver donation. We aimed at identifying risk factors and developing a score for prediction of postoperative complications (POCs) after LDLD in donors. This is a retrospective cohort study in 688 donors between June 1995 and February 2014 at Hospital Sírio-Libanês and A.C. Camargo Cancer Center, in São Paulo, Brazil. Primary outcome was POC graded ≥III according to the Clavien-Dindo classification. Left lateral segment (LLS), left lobe (LL), and right lobe resections (RL) were conducted in 492 (71.4%), 109 (15.8%), and 87 (12.6%) donors, respectively. In total, 43 (6.2%) developed POCs, which were more common after RL than LLS and LL (14/87 (16.1%) versus 23/492 (4.5%) and 6/109 (5.5%), resp., p < 0.001). Multivariate analysis showed that RL resection (OR: 2.81, 95% CI: 1.32 to 3.01; p = 0.008), smoking status (OR: 3.2, 95% CI: 1.35 to 7.56; p = 0.012), and blood transfusion (OR: 3.15, 95% CI: 1.45 to 6.84; p = 0.004) were independently associated with POCs. RL resection, intraoperative blood transfusion, and smoking were associated with increased risk for POCs in donors.

Serum proinflammatory cytokines and nutritional status in pediatric chronic liver disease

AIM: To evaluate the nutritional status and its association with proinflammatory cytokines in children with chronic liver disease.

METHODS: We performed a cross-sectional study with 43 children and adolescents, aged 0 to 17 years, diagnosed with chronic liver disease. All patients regularly attended the Pediatric Hepatology Unit and were under nutritional follow up. The exclusion criteria were fever from any etiology at the time of enrollment, inborn errors of the metabolism and any chronic illness. The severity of liver disease was assessed by Child-Pugh, Model for End-stage Liver Disease (MELD) and Pediatric End Stage Liver Disease (PELD) scores. Anthropometric parameters were height/age, body mass index/age and triceps skinfold/age according to World Health Organization standards. The cutoff points for nutritional status were risk of malnutrition (Z-score < -1.00) and malnutrition (Z-score < -2.00). Interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α levels were assessed by commercial ELISA kits. For multivariate analysis, linear regression was applied to assess the association between cytokine levels, disease severity and nutritional status.

RESULTS: The median (25^th-75^th centile) age of the study population was 60 (17-116)-mo-old, and 53.5% were female. Biliary atresia was the main cause of chronic liver disease (72%). With respect to Child-Pugh score, cirrhotic patients were distributed as follows: 57.1% Child-Pugh A, a mild presentation of the disease, 34.3% Child-Pugh B, a moderate stage of cirrhosis and 8.6% Child-Pugh C, were considered severe cases. PELD and MELD scores were only above the cutoff point in 5 cases. IL-6 values ​​were increased in patients at nutritional risk (34.9%) compared with those who were well-nourished [7.12 (0.58-34.23) pg/mL vs 1.63 (0.53-3.43) pg/mL; P = 0.02], correlating inversely with triceps skinfold-for-age z-score (r_s = -0.61; P < 0.001). IL-6 levels were associated with liver disease severity assessed by Child-Pugh score (P = 0.001). This association remained significant after adjusting for nutritional status in a linear regression model.

CONCLUSION: High IL-6 levels were found in children with chronic liver disease at nutritional risk. Inflammatory activity may be related to nutritional status deterioration in these patients.

Impact of Kasai portoenterostomy on liver transplantation outcomes: A retrospective cohort study of 347 children with biliary atresia

Biliary atresia (BA) is the main diagnosis leading to liver transplantation (LT) in children. When diagnosed early in life, a Kasai portoenterostomy (Kasai-PE) can prevent or postpone LT. Instances of previous operations can result in difficulties during the LT. We hypothesized that a previous Kasai-PE could affect LT outcomes. A retrospective cohort study of 347 BA patients submitted to LT between 1995 and 2013 at Hospital Sírio-Libanês and A. C. Camargo Cancer Center was conducted. Patients were divided into those with a previous Kasai portoenterostomy early failure (K-EF), Kasai portoenterostomy late failure (K-LF), and those with no Kasai portoenterostomy (No-K). Primary outcomes were patient and graft survival. A total of 94 (27.1%) patients had a K-EF, 115 (33.1%) had a K-LF, and 138 (39.8%) had No-K before LT. Children in the K-LF group were older and had lower Pediatric End-Stage Liver Disease (PELD) scores. Patients in both K-EF and K-LF groups had more post-LT biliary complications. After Cox-multivariate analysis adjusting for confounding factors to determine the influence of Kasai-PE on patient and graft survival, the K-LF group had an 84% less probability of dying and a 55% less chance to undergo retransplantation. The K-LF group had a protective effect on posttransplant patient and graft survival. When properly performed, the Kasai procedure can postpone LT and positively affect outcomes. Having a K-EF and having not performed a Kasai-PE had the same effect in patient and graft survival; however, a previous Kasai-PE can increase post-LT complications as biliary complications and bowel perforations.

Lessons Learned From Review of a Single Center Experience With 500 Consecutive Liver Transplants in a Region With Insufficient Deceased-Donor Support

OBJECTIVES

We present here the outcomes of our first 500 liver transplants and discuss the lessons learned during this time.

MATERIALS AND METHODS

We retrospectively analyzed the first 500 consecutive transplants within the listing criteria of the United Network for Organ Sharing, with recipients and donors with minimum 1-year follow-up. Patient survival and donor complications were analyzed for 31 liver transplant recipients with hepatocellular carcinoma beyond the Milan criteria who had transplant performed during the same time.

RESULTS

Between August 2006 and March 2013, there were 519 liver transplants performed in 500 patients (365 adult, 135 pediatric). There were 394 living-donor and 125 deceased-donor liver transplants. In addition, 31 adult liver transplants were performed in patients with hepatocellular carcinoma beyond Milan criteria (22 living-donor and 9 deceased-donor transplants). The main cause of chronic liver failure was biliary atresia in pediatric patients (30.4%) and chronic hepatitis B infection in adults (35.6%). The complication rate for primary nonfunction was 3.8%, overall biliary complications 24.0% (significantly higher after adult living-donor liver transplant, 30.3%), hepatic artery thrombosis 1.6%, portal vein thrombosis 3.0%, retransplant 3.8%, acute cellular rejection 29.6%, and bacterial infection 39.4%. Overall 1-, 3-, and 5-year patient survival rates in the first 500 consecutive transplants performed on recipients within United Network for Organ Sharing listing criteria were 87.8%, 85.0%, and 78.6%; for hepatocellular carcinoma patients beyond the Milan criteria, survival rates were 71.9%, 52.5%, and 38.2%.

CONCLUSIONS

In regions without a sufficient number of deceased donors, living-donor liver transplant, with its associated problems, is the only alternative to deceased-donor liver transplant. Liver transplant requires teamwork, with all players working well together for a successful outcome. The important keys to success in liver transplant include decision-making, timing, surgical skills, experience, and close follow-up.

Pediatric transplantation: preventing thrombosis

Due to progressive advances in surgical techniques, immunosuppressive therapies, and supportive care, outcomes from both solid organ transplantation and hematopoietic stem cell transplantation continue to improve. Thrombosis remains a challenging management issue in this context, with implications for both graft survival and long-term quality of life. Unfortunately, there remains a general paucity of pediatric-specific data regarding thrombosis incidence, risk stratification, and the safety or efficacy of preventative strategies with which to guide treatment algorithms. This review summarizes the available evidence and rationale underlying the spectrum of current practices aimed at preventing thrombosis in the transplant recipient, with a particular focus on risk factors, pathophysiology, and described antithrombotic regimens.

Percutaneous yttrium aluminum garnet-laser lithotripsy of intrahepatic stones and casts after liver transplantation

Bile duct stones and casts (BDSs) contribute importantly to morbidity after liver transplantation (LT). The purpose of this study was to estimate the clinical efficacy, safety, and long-term results of percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) in transplant recipients and to discuss underlying factors affecting the outcome. A retrospective chart review revealed 18 recipients with BDSs treated by PTCSL laser lithotripsy with a holmium-yttrium aluminum garnet laser probe at 365 to 550 µm. They were analyzed in a median follow-up time of 55 months. In all but 1 patient (17/18 or 94%), it was technically feasible to clear all BDSs with a mean of 1.3 sessions. PTCSL was unsuccessful in 1 patient because of multiple stones impacting the bile ducts bilaterally; 17% had early complications (Clavien II). All biliary casts were successfully cleared; 39% had total remission; 61% needed additional interventions in the form of percutaneous transhepatic cholangiography and dilation (17%), re-PTCSL (11%), self-expandable metallic stents (22%), or hepaticojejunostomy (6%); and 22% eventually underwent retransplantation. The overall liver graft survival rate was 78%. Two patients died during follow-up for reasons not related to their BDS. Nonanastomotic strictures (NASs) were significantly associated with treatment failure. We conclude that PTCSL in LT patients is safe and feasible. NASs significantly increased the risk of relapse. Repeated minimally invasive treatments, however, prevented graft failure in 78% of the cases.

The role of adult living donor liver transplantation and recent advances

Twenty years since the first cases were described, adult living donor liver transplantation (ALDLT) is now considered a valid option to expand the donor pool in view of the ongoing shortage of organs and the high waiting list mortality rate. Despite the rapid evolution and acceptance of this complex process of donation and transplantation in clinical practice, the indications, outcome, ethical considerations and quality and safety aspects continue to evolve based on new data from large cohort studies. This article reviews the surgical and clinical advances in the field of liver transplantation, focusing on technical refinements and discussing the issues that may lead to a further expansion of this complex surgical procedure and the role of ALDLT.

Cost-effective analysis of screening for biliary atresia with the stool color card

BACKGROUND

Biliary atresia (BA) is the leading cause of pediatric end-stage liver disease and liver transplantation in the United States. Early diagnosis leads to improved outcomes, but diagnosis is often delayed, leading to increased rates of transplantation and mortality.

METHODS

A Markov model was developed to simulate the natural history and transplant-related outcomes of patients with BA in a US cohort studied for 20 years. Data regarding proportions of individuals in different health states, including transplant and death, were obtained from published literature. Costs were derived from the literature and the Johns Hopkins database of charges using the cost-to-charge ratio. Strategy A represented the status quo and assumed no screening. Strategy B used nationwide screening with the stool color card developed by the Taiwan Health Bureau. The cost associated with both strategies was compared with the number of life-years gained, deaths, and the number of transplants for a 20-year interval. A dominant strategy was one that was associated with lower cost alongside improved outcomes, including increases in life-years gained, reductions in number of deaths, and reductions in number of transplants. One-way and probabilistic sensitivity analyses were performed.

RESULTS

In strategy A, the 20-year cost was $142,479,725 with 3702 life-years, 74 deaths and 158 liver transplants. For strategy B, the cost was $133,893,563 with 3731.7 life-years, 71 deaths and 147 liver transplants. There was a >97% probability that screening with the stool color card would be cost saving and associated with an increase in life-years gained. Among all parameters, only stool color card specificity was associated with the potential for screening to no longer be cost saving.

CONCLUSIONS

Compared with no screening, screening with the stool color card is a dominant strategy associated with lower costs and better outcomes. These findings suggest that screening with the stool color card could be an important, economically feasible strategy for improving outcomes in BA in the United States.

Analysis of factors associated with portal vein thrombosis in pediatric living donor liver transplant recipients

The technique of vascular reconstruction plays a major role in the outcome of living donor liver transplantation (LDLT). An increased use of vascular grafts (VGs) as replacements for sclerotic portal veins has become a standard technique for our group. The aim of this study was to analyze the factors associated with portal vein thrombosis (PVT) in pediatric LDLT. We performed a retrospective analysis of 486 primary pediatric LDLT procedures performed between October 1995 and May 2013. VGs used for portal reconstruction included living donor inferior mesenteric veins, living donor ovarian veins, recipient internal jugular veins, deceased donor iliac arteries, and deceased donor iliac veins. Thirty-four patients (7.0%) developed PVT. The incidence of PVT dropped from 10.1% to 2%; the overall utilization of VGs increased from 3.5% to 37.1%. In a multivariate analysis, only the use of VGs remained an independent risk factor for the occurrence of PVT (hazard ratio = 7.2, 95% confidence interval = 2.8-18.7, P < 0.001). There was no difference in survival rates between patients with PVT and patients without PVT. No patient with PVT underwent retransplantation. In conclusion, the use of VGs was independently associated with the development of PVT. Over time, there was a reduction in the incidence of early PVT in this cohort, and there was a trend toward a reduction in total PVT. The occurrence of isolated PVT in this study was not associated with decreased patient or graft survival.

Liver transplantation in Latin America: the state-of-the-art and future trends

We reviewed the current status of liver transplantation in Latin America. We used data from the Latin American and Caribbean Transplant Society and national organizations and societies, as well as information obtained from local transplant leaders. Latin America has a population of 589 million (8.5% of world population) and more than 2,500 liver transplantations are performed yearly (17% of world activity), resulting in 4.4 liver transplants per million people (pmp) per year. The number of liver transplantations grows at 6% per year in the region, particularly in Brazil. The top liver transplant rates were found in Argentina (10.4 pmp), Brazil (8.4 pmp), and Uruguay (5.5 pmp). The state of liver transplantation in some countries rivals those in developed countries. Model for End-Stage Liver Disease-based allocation, split, domino, and living-donor adult and pediatric transplantations are now routinely performed with outcomes comparable to those in advanced economies. In contrast, liver transplantation is not performed in 35% of Latin American countries and lags adequate resources in many others. The lack of adequate financial coverage, education, and organization is still the main limiting factor in the development of liver transplantation in Latin America. The liver transplant community in the region should push health care leaders and authorities to comply with the Madrid and Istambul resolutions on organ donation and transplantation. It must pursue fiercely the development of registries to advance the science and quality control of liver transplant activities in Latin America.

Diagnosis and management of biliary complications in pediatric living donor liver transplant recipients

The incidence of biliary complications (BCs) after living donor liver transplantation (LDLT) can reach 40%. Published data on the pediatric population are limited, and treatment protocols vary. Our aim was to describe the clinical scenario for BCs and treatment approaches after LDLT. Between October 1995 and December 2012, 489 pediatric LDLT procedures were performed. BCs developed in 71 patients (14.5%). Biliary strictures (BSs) developed in 45 (9.2%) patients, and bile leaks (BLs) developed in 33 patients (6.7%). The BL diagnosis was clinical in all cases, and 69.7% of the patients underwent surgery. Nearly half of the BS cases had clinical features or suggestive ultrasound findings. Liver biopsy findings suggested BSs in 51.7%. Percutaneous transhepatic cholangiography was performed in 95.6% of the BS patients. The success rate was 77% [mean number of percutaneous biliary interventions (PBIs) = 3.9 ± 1.98, median drainage time = 8 months]. In conclusion, BL patients can be managed with conservative therapy, even though most of these patients will ultimately be treated with surgery. Diagnosing a BS requires a high degree of clinical suspicion because the available resources for its identification can fail in up to 50% of cases. A higher number of PBIs and the use of a drainage catheter for a longer time may be required to achieve better results with this technique.

Frequency of and factors associated with vascular complications after pediatric liver transplantation

OBJECTIVE

to evaluate the frequency and factors associated with vascular complications after pediatric liver transplantation.

METHOD

risk factors were evaluated in 99 patients under 18 years of age with chronic liver disease who underwent deceased donor liver transplantation (DDLT) between March of 1995 and November of 2009 at the Hospital de Clínicas de Porto Alegre, Brazil. The variables analyzed included donor and recipient age, gender, and weight; indication for transplant; PELD/MELD scores; technical aspects; postoperative vascular complications; and survival.

RESULTS

vascular complications occurred in 19 patients (19%). Arterial events were most common, occurred earlier in the postoperative period, and were associated with high graft loss and mortality rates. In the multivariate analysis, the following factors were identified: portal vein diameter ≤ 3mm, donor-to-recipient body weight ratio (DRWR), prolonged ischemic time, and use of arterial grafts.

CONCLUSION

the choice of treatment depends on the timing of diagnosis; however, in this study, surgical revision or correction produced worse outcomes than percutaneous angioplasty. The reduction of risk factors and early detection of vascular complications are key elements to a successful transplantation.

Long-term outcomes of pediatric living donor liver transplantation in Japan: an analysis of more than 2200 cases listed in the registry of the Japanese Liver Transplantation Society

The Japanese Liver Transplantation Society (JLTS) was established in 1980 in order to characterize and follow trends in patient characteristics and graft survival among all liver transplant patients in Japan. This study analyzed the comprehensive factors that may influence the outcomes of pediatric patients who undergo living donor liver transplantation (LDLT) by evaluating the largest cohort in the world. Between November 1989 and December 2010, 2224 pediatric patients underwent LDLT in Japan. There were 998 male (44.9%) and 1226 female donors (55.1%) without donor mortalities related to transplant surgery. There were 946 male (42.5%) and 1278 female (57.5%) recipients with a median age of 4.0 years (range: 13 days to 17.9 years). Cholestatic liver disease was the leading indication for LDLT (n = 1649; 76.2%), followed by metabolic disorders (n = 194; 8.7%), acute liver failure (n = 192; 8.6%) and neoplastic liver disease (n = 66; 3.0%). The 1-, 5-, 10- and 20-year patient survival rates were 88.3%, 85.4%, 82.8% and 79.6%, respectively. Blood-type incompatibility, recipient age, etiology of liver disease and transplant era were found to be significant predictors of overall survival. We are able to achieve satisfactory long-term pediatric patient survival outcomes in the JLTS series without compromising the living donors.

Rapid correction rate of hyponatremia as an independent risk factor for neurological complication following liver transplantation

Hyponatremia is prevalent before liver transplantation and generally corrected immediately after transplantation. However, the clinical significance of correction rate of hyponatremia is not well investigated. The prognostic impact of pre-transplant serum sodium concentrations and post-transplant correction rate of hyponatremia were assessed. A total of 512 patients who received orthotopic liver transplants were enrolled. The correction rate of hyponatremia (delta sodium, ΔNa) was calculated based on the data collected during the first 48 hours following liver transplantation. Outcomes, including in-hospital mortality, delirium, neurological complications, acute kidney injury, and infections, were compared according to the serum sodium levels (sNa < 125, 125-135, and ≥ 135 mmol/L), and the risk factors for in-hospital mortality and neurological complications were analyzed using multivariate logistic regression methods. Patients with severe hyponatremia (sNa < 125 mmol/L) had higher rates of in-hospital mortality (9.6%, P = 0.010), delirium (54.8%, P = 0.003), neurological complications (24.7%, P = 0.003), and acute kidney injury (57.5%, P = 0.005). In multivariate analysis, serum sodium levels (OR = 0.975, P = 0.402) and delta sodium (OR = 1.097, P = 0.066) were not independent risk factors for in-hospital mortality. However, delta sodium (OR = 1.093, P = 0.003) and fast correction rate of hyponatremia (ΔNa ≥ 12 mmol/L/24h, OR = 3.397, P = 0.023) were significantly associated with post-transplant neurological complications. Pre-transplantation hyponatremia was not independently associated with clinical outcomes. However, rapid correction of hyponatremia is an independent risk factor for the development of post-transplant neurological complications.

Technical aspects and outcomes of living donor liver transplantation for pediatric patients with situs inversus

The vascular anomalies encountered in patients with biliary atresia associated with polysplenia syndrome and situs inversus (SI) demand technical refinements when liver transplantation is being performed. The available data describing the technique used in living donor liver transplantation (LDLT) in this population are limited; the short vascular stumps of the donor's liver can impart additional technical difficulties during vascular reconstruction. Here we describe our experience with 9 children with biliary atresia and SI who underwent LDLT. In our series, the retrohepatic vena cava was absent for 7 patients, 7 had a preduodenal portal vein (PV), and 4 had a variant arterial anatomy. The donor's left hepatic vein was anastomosed to the confluence of the recipient's 3 hepatic veins in 7 patients. Vascular grafts were used for PV reconstruction in 3 cases. A left lateral segment graft was used in all but 1 patient who needed a graft reduction. All grafts were placed in the upper left abdomen. There were no vascular complications after transplantation. All patients were alive and well at a median follow-up of 55 months. In conclusion, LDLT can be successfully performed in pediatric patients with SI. Complex vascular anomalies associated with the use of partial liver grafts obtained from living donors are not associated with an increased occurrence of vascular complications.