Liver transplantation in very small infants

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Long-Term Outcome after Liver Transplantation for Progressive Familial Intrahepatic Cholestasis

Background and Objectives: Progressive familial intrahepatic cholestasis (PFIC) is a rare autosomal recessive inherited disease divided into five types (PFIC 1-5). Characteristic for all types is early disease onset, which may result clinically in portal hypertension, fibrosis, cirrhosis, hepatocellular carcinoma (HCC), and extrahepatic manifestations. Liver transplantation (LT) is the only successful treatment approach. Our aim is to present the good long-term outcomes after liver transplantation for PFIC1, focusing on liver function as well as the occurrence of extrahepatic manifestation after liver transplantation. Materials and Methods: A total of seven pediatric patients with PFIC1 underwent liver transplantation between January 1999 and September 2019 at the Department of Surgery, Charité Campus Virchow Klinikum and Charité Campus Mitte of Charité-Universitätsmedizin Berlin. Long-term follow-up data were collected on all patients, specifically considering liver function and extrahepatic manifestations. Results: Seven (3.2%) recipients were found from a cohort of 219 pediatric patients. Two of the seven patients had multilocular HCC in cirrhosis. Disease recurrence or graft loss did not occur in any patient. Two patients (male, siblings) had persistently elevated liver parameters but showed excellent liver function. Patient and graft survival during long-term follow-up was 100%, and no severe extrahepatic manifestations requiring hospitalization or surgery occurred. We noted a low complication rate during long-term follow-up and excellent patient outcome. Conclusions: PFIC1 long-term follow-up after LT shows promising results for this rare disease. In particular, the clinical relevance of extrahepatic manifestations seems acceptable, and graft function seems to be barely affected. Further multicenter studies are needed to analyze the clinically inhomogeneous presentation and to better understand the courses after LT.

Survival and Complication of Liver Transplantation in Infants: A Systematic Review and Meta-Analysis

Background: Modern surgical techniques and scientific advancements have made liver transplant (LT) in infants feasible. However, there are only a small number of studies examining the short- as well as long-term outcomes of LT in this vulnerable subset of children. Methods: Comprehensive searches were done systematically through the PubMed, Scopus, and Google scholar databases. Studies that were retrospective record based or adopted a cohort approach and reported either patient survival rates or graft survival rates or complications of LT in infants were included in the meta-analysis. Statistical analysis was done using STATA version 13.0. Results: A total of 22 studies were included in the meta-analysis. The overall pooled patient survival rate at 1 year, >1-5 years, and >5 years post-transplantation was 85% (95% CI: 78--92%), 71% (95% CI: 59-83%), and 80% (95% CI: 69-91%), respectively. The overall pooled graft survival rate at 1 year, >1-5 years, and >5 years post-transplantation was 72% (95% CI: 68-76%), 62% (95% CI: 46-78%), and 71% (95% CI: 56-86%), respectively. The overall pooled rate for vascular complications, need for re-transplantation, biliary complications, and infection/sepsis was 12% (95% CI: 10-15%), 16% (95% CI: 12-20%), 15% (95% CI: 9-21%), and 50% (95% CI: 38-61%), respectively. Conclusion: The current meta-analysis showed modest patient and graft survival rates for infant liver transplantation. However, the complication rates related to infection/sepsis were high. More comprehensive evidence is required from studies with larger sample sizes and a longer duration of follow-up.

Feasibility and safety of using low-body-weight donors in pediatric liver transplantation

BACKGROUND

Donors with low-body-weight were previously reported to be related to inferior recipient outcomes in pediatric liver transplantation. However, the scarce availability of age and size-matched organs has encouraged us to re-evaluate the feasibility and safety of using low-body-weight donors.

METHODS

We retrospectively analyzed 91 deceased donor pediatric liver transplantation between January 2014 and December 2016, donor weight less than 5 kg was defined as low-body-weight donors. The recipients were divided into two groups according to donor weight. (≤5 kg and 5 kg < to ≤20 kg). Donor and recipient characteristics, perioperative data, postoperative complications as well as graft and recipient survival rate were compared RESULTS: The recipients and grafts recovery after transplantation were comparable between two groups. The recipients receiving low-body-weight donors showed higher risk of hepatic artery thrombosis and small-for-size syndrome, however, these complications can effectively be treated by our strategies. The 2-year patient survival rates were 92.9% and 95.2%, 2-year graft survival rates were 92.9% and 93.7% in Groups 1 and 2, without significant difference.

CONCLUSIONS

Our finding suggested that the utility of livers from low-body-weight donors is a potential strategy to increase donor availability in well-selected pediatric recipients.

LEVEL OF EVIDENCE

III.

Utility of neonatal donors in pediatric liver transplantation: A single-center experience

BACKGROUND

The lack of age- and size-matched organs result in higher waiting list mortality in pediatric recipients than adults. Organs from deceased newborns and infants are a valuable source to increase donor pool in pediatric liver transplantation. However, the feasibility and safety of using neonatal donors have not been well evaluated.

METHODS

From 2014 to 2016, 48 deceased donor pediatric liver transplantations with donor age younger than 1 year old in our center were enrolled in this study. The recipients were divided into three groups based on the donor age (<1 month, 1 month ≤ to <3 months, and 3 months ≤ to <1 year). Recipient's characteristics, perioperative data, and postoperative complications were compared.

RESULTS

Two-year patient survival rates were 87.5%, 94.4%, and 95.5%, and 2-year graft survival rates were 75%, 94.4%, and 95.5%, respectively, without significant difference. The liver grafts from donors younger than 3 months were more advantageous in terms of acute rejection and virus infection, while the young grafts were related to slight higher incidence of hepatic artery thrombosis and SFSS. Those complications could be effectively prevented or treated by our perioperative care strategies. In addition, eight recipients who received neonatal livers achieved comparable outcomes with recipients with older livers.

CONCLUSION

Our data revealed that the application of liver grafts from donors younger than 1 year old could achieve excellent outcome. In particular, neonatal donors could be safely used in well-selected patients.

Predicting early outcomes of liver transplantation in young children: The EARLY study

AIM

To determine potentially modifiable predictors of early outcomes after liver transplantation in children of age < 3 years.

METHODS

This study was a retrospective chart review including all consecutive children of age less than 3-years-old having had a liver transplant done at the Western Canadian referral center from June 2005 to June 2015. Pre-specified potential predictor variables and primary and secondary outcomes were recorded using standard definitions and a case report form. Associations between potential predictor variables and outcomes were determined using univariate and multiple logistic [odds ratio (OR); 95%CI] or linear (effect size, ES; 95%CI) regressions.

RESULTS

There were 65 children, of mean age 11.9 (SD 7.1) mo and weight 8.5 (2.1) kg, with biliary-atresia in 40 (62%), who had a living related donor [LRD; 29 (45%)], split/reduced [21 (32%)] or whole liver graft [15 (23%)]. Outcomes after liver transplant included: ventilator-days of 12.5 (14.1); pediatric intensive care unit mortality of 5 (8%); re-operation in 33 (51%), hepatic artery thrombosis (HAT) in 12 (19%), portal vein thrombosis (PVT) in 11 (17%), and any severe complication (HAT, PVT, bile leak, bowel perforation, intraabdominal infection, retransplant, or death) in 32 (49%) patients. Predictors of the prespecified primary outcomes on multiple regression were: (1) HAT: split/reduced (OR 0.06; 0.01, 0.76; P = 0.030) or LRD (OR 0.16; 0.03, 0.95; P = 0.044) vs whole liver graft; and (2) ventilator-days: surgeon (P < 0.05), lowest antithrombin (AT) postoperative day 2-5 (ES -0.24; -0.47, -0.02; P = 0.034), and split/reduced (ES -12.5; -21.8, -3.2; P = 0.009) vs whole-liver graft. Predictors of the pre-specified secondary outcomes on multiple regression were: (1) any thrombosis: LRD (OR 0.10; 0.01, 0.71; P = 0.021) or split/reduced (OR 0.10; 0.01, 0.85; P = 0.034) vs whole liver graft, and lowest AT postoperative day 2-5 (OR 0.93; 0.87, 0.99; P = 0.038); and (2) any severe complication: surgeon (P < 0.05), lowest AT postoperative day 2-5 (OR 0.92; 0.86-0.98; P = 0.016), and split/reduced (OR 0.06; 0.01, 0.78; P = 0.032) vs whole-liver graft.

CONCLUSION

In young children, whole liver graft and surgeon was associated with more complications, and higher AT postoperative day 2-5 was associated with fewer complications early after liver transplantation.

Living donor liver transplantation during the first 3 months of life

Living donor liver transplantation (LDLT) is now an established technique for treating children with end-stage liver disease. Few data exist about liver transplantation (LT) for exclusively young infants, especially infants of <3 months of age. We report our single-center experience with 12 patients in which LDLT was performed during the first 3 months of life and compare the results with those of older infants who underwent LT. All of the patients were treated at the National Center of Child Health and Development, Tokyo, Japan. Between November 2005 to November 2016, 436 children underwent LT. Twelve of these patients underwent LT in the first 3 months of life (median age, 41 days; median weight, 4.0 kg). The indications for transplantation were fulminant hepatic failure (n = 11) and metabolic liver disease (n = 1). All the patients received the left lateral segment (LLS) in situ to mitigate the problem of graft-to-recipient size discrepancy. A reduced LLS graft was used in 11 patients and a segment 2 monosegment graft was used in 1 patient. We compared the results with those of infants who were 4-6 months of age (n = 67) and 7-12 months of age (n = 110) who were treated in the same study period. There were significant differences in the Pediatric End-Stage Liver Disease score and the conversion rate of tacrolimus to cyclosporine in younger infants. Furthermore, the incidence of biliary complications, bloodstream infection, and cytomegalovirus infection tended to be higher, whereas the incidence of acute cellular rejection tended to be lower in younger infants. The overall cumulative 10-year patient and graft survival rates in recipients of <3 months of age were both 90.9%. LDLT during the first 3 months of life appears to be a feasible option with excellent patient and graft survival. Liver Transplantation 23 1051-1057 2017 AASLD.

Presenting Features and Prognosis of Ischemic and Nonischemic Neonatal Liver Failure

OBJECTIVES

To describe the epidemiological features, clinical characteristics and outcomes of neonates diagnosed with liver failure, as well as determine prognostic factors.

METHODS

Cohort study conducted at a single tertiary referral and university-affiliated pediatric center. Hospital records of all neonates diagnosed with liver failure between January 2003 and December 2015 were retrospectively reviewed, and data on clinical and laboratory findings, treatment, and outcomes were collected. Survival analysis (Kaplan-Meier) and Cox regression were performed to identify prognostic factors at diagnosis. Liver failure diagnosis was established using the pediatric acute liver failure study group's diagnostic criteria for every patient with coagulopathy and biochemical pattern of liver disease.

RESULTS

Forty-five patients were included. In our series, most cases were secondary to ischemia (28.9%). Other causes were neonatal hemochromatosis (17.8%), viral infections (13.3%), and inborn errors of metabolism (13.3%). A total 55.6% (25/45) of the patients died (median age: 16 days; range 1-235 days). Alanine aminotransferase (ALT) at diagnosis was associated with higher mortality or the need for liver transplantation on day 21 after diagnosis (P = .006). For every 500 IU/L increase in ALT serum levels, the mortality/liver transplantation rate increased 1.3 times (hazard ratio 95% confidence interval: 1.1-1.6). Although ischemic neonatal acute liver failure presents with higher ALT levels, these cases appear to have better outcomes. Higher international normalized ratio tended to increase mortality/transplantation (hazard ratio 1.02; 95% confidence interval 0.91-1.2).

CONCLUSIONS

Neonatal liver failure should perhaps be considered in the differential diagnoses of any coagulopathy. ALT and international normalized ratio levels at diagnosis could predict prognosis in the short term. Ischemic liver failure appears to have a better prognosis.

Outcomes in infants listed for liver transplantation: A retrospective cohort study using the United Network for Organ Sharing database

LT in neonates and young infants can be challenging due to a variety of factors. To describe the waitlist mortality rates and outcomes of patients listed and transplanted as infants identified from the UNOS database. Infants listed for LT between January 1985 and September 2010 were identified from the UNOS database. Mortality on the waitlist as well as outcomes post-LT was compared between infants aged ≤60 days (Group 1), 61-179 days (Group 2), and 180-364 days (Group 3). Of 6763 infants listed for LT (Group 1 n = 496, Group 2 n = 2404, Group 3 n = 3863), mean age at listing was 196 ± 87 days (Group 1, 29 ± 16 days; Group 2, 132 ± 32 days; Group 3, 257 ± 52 days). Waitlist mortality was highest in Group 1 (Group 1 vs. 3 HR 3.01, 95% CI 2.19-4.15, Group 2 vs. Group 3 HR 0.82, 95% CI 0.66-1.03). One- and five-yr graft survival was 59.6% and 42% (Group 1), 66% and 45% (Group 2), and 66.8% and 41% (Group 3) (one-yr survival p = 0.20; five-yr survival p = 0.19). Infants listed for LT at age ≤60 days had greater waitlist mortality risk than older infants. Infants undergoing LT at age ≤60 days had similar rates of patient and graft survival to older infants.

Survival Outcomes Following Pediatric Liver Transplantation (Pedi-SOFT) Score: A Novel Predictive Index

A prognostic index to predict survival after liver transplantation could address several clinical needs. Here, we devised a scoring system that predicts recipient survival after pediatric liver transplantation. We used univariate and multivariate analysis on 4565 pediatric liver transplant recipients data and identified independent recipient and donor risk factors for posttransplant mortality at 3 months. Multiple imputation was used to account for missing variables. We identified five factors as significant predictors of recipient mortality after pediatric liver transplantation: two previous transplants (OR 5.88, CI 2.88-12.01), one previous transplant (OR 2.54, CI 1.75-3.68), life support (OR 3.68, CI 2.39-5.67), renal insufficiency (OR 2.66, CI 1.84-3.84), recipient weight under 6 kilograms (OR 1.67, CI 1.12-2.36) and cadaveric technical variant allograft (OR 1.38, CI 1.03-1.83). The Survival Outcomes Following Pediatric Liver Transplant score assigns weighted risk points to each of these factors in a scoring system to predict 3-month recipient survival after liver transplantation with a C-statistic of 0.74. Although quite accurate when compared with other posttransplant survival models, we would not advocate individual clinical application of the index.

Effects of ischemic preconditioning in a pig model of large-for-size liver transplantation

OBJECTIVE

In most cases of pediatric liver transplantation, the clinical scenario of large-for-size transplants can lead to hepatic dysfunction and a decreased blood supply to the liver graft. The objective of the present experimental investigation was to evaluate the effects of ischemic preconditioning on this clinical entity.

METHODS

Eighteen pigs were divided into three groups and underwent liver transplantation: a control group, in which the weights of the donors were similar to those of the recipients, a large-for-size group, and a large-for-size + ischemic preconditioning group. Blood samples were collected from the recipients to evaluate the pH and the sodium, potassium, aspartate aminotransferase and alanine aminotransferase levels. In addition, hepatic tissue was sampled from the recipients for histological evaluation, immunohistochemical analyses to detect hepatocyte apoptosis and proliferation and molecular analyses to evaluate the gene expression of Bax (pro-apoptotic), Bcl-XL (anti-apoptotic), c-Fos and c-Jun (immediate-early genes), ischemia-reperfusion-related inflammatory cytokines (IL-1, TNF-alpha and IL-6, which is also a stimulator of hepatocyte regeneration), intracellular adhesion molecule, endothelial nitric oxide synthase (a mediator of the protective effect of ischemic preconditioning) and TGF-beta (a pro-fibrogenic cytokine).

RESULTS

All animals developed acidosis. At 1 hour and 3 hours after reperfusion, the animals in the large-for-size and large-for-size + ischemic preconditioning groups had decreased serum levels of Na and increased serum levels of K and aspartate aminotransferase compared with the control group. The molecular analysis revealed higher expression of the Bax, TNF-alpha, I-CAM and TGF-beta genes in the large-for-size group compared with the control and large-for-size + ischemic preconditioning groups. Ischemic preconditioning was responsible for an increase in c-Fos, IL-1, IL-6 and e-NOS gene expression.

CONCLUSION

Ischemia-reperfusion injury in this model of large-for-size liver transplantation could be partially attenuated by ischemic preconditioning.

Neonatal haemochromatosis with reversible pituitary involvement

Neonatal haemochromatosis is a rare alloimmune gestational disease with a high mortality. The hallmark of neonatal haemochromatosis is severe neonatal liver failure associated with extrahepatic siderosis. Thus far, no pituitary dysfunction has been reported to result from the tissue damage associated with extrahepatic siderosis. The present report describes a neonate with neonatal haemochromatosis and secondary hypothyroidism associated with pituitary iron deposition. Both the conditions were successfully treated by ABO-incompatible liver transplantation. Pituitary gland dysfunction is another possible extrahepatic manifestation of neonatal haemochromatosis, and it is reversible after liver transplantation.

Long term outcomes of pediatric liver transplantation according to age

Liver transplantation (LT) has been the key therapy for end stage liver diseases. However, LT in infancy is still understudied. From 1992 to 2010, 152 children had undergone LT in Seoul National University Hospital. Operations were performed on 43 patients aged less than 12 months (Group A) and 109 patients aged over 12 months (Group B). The mean age of the recipients was 7 months in Group A and 74 months in Group B. The patients' survival rates and post-LT complications were analyzed. The mean Pediatric End-stage Liver Disease score was higher in Group A (21.8) than in Group B (13.4) (P = 0.049). Fulminant hepatitis was less common in Group A (4.8%) than in Group B (13.8%) (P = 0.021). The post-transplant lymphoproliferative disorder and portal vein complication were more common in Group A (14.0%, 18.6%) than in Group B (1.8%, 3.7%) (P = 0.005). However, the 1, 5, and 10 yr patient survival rates were 93%, 93%, and 93%, in Group A and 92%, 90%, and 88% in Group B (P = 0.212). The survival outcome of pediatric LT is excellent and similar regardless of age. LTs in infancy are not riskier than those of children.

Long-term deleterious effects of aortohepatic conduits in primary liver transplantation: proceed with caution

Aortohepatic conduits provide a vital alternative for graft arterialization during liver transplantation. Conflicting results exist with respect to the rates of comorbidities, and long-term survival data on primary grafts are lacking. To identify the complications associated with aortohepatic conduits in primary liver transplantation and their impact on survival, we conducted a single-center, retrospective cohort analysis of all consecutive adult (n = 1379) and pediatric primary liver transplants (n = 188) from 1998 to 2009. The outcomes of aortohepatic conduits were compared to those of standard arterial revascularization. Adults with a conduit (n = 267) demonstrated, in comparison with adults with standard arterialization (n = 1112), an increased incidence of late (>1 month after transplantation) hepatic artery thrombosis (HAT; 4.1% versus 0.7%, P < 0.001) and ischemic cholangiopathy (7.5% versus 2.7%, P < 0.001) and a lower 5-year graft survival rate (61% versus 70%, P = 0.01). The adjusted hazard ratio (HR) for graft loss in the conduit group was 1.38 [95% confidence interval (CI) = 1.03-1.85, P = 0.03]. Notably, the use of conduits (HR = 4.91, 95% CI = 1.92-12.58) and a warm ischemia time > 60 minutes (HR = 11.12, 95% CI = 3.06-40.45) were independent risk factors for late HAT. Among children, the complication profiles were similar for the conduit group (n = 81) and the standard group (n = 107). In the pediatric cohort, although the 5-year graft survival rate for the conduit group (69%) was significantly impaired in comparison with the rate for the standard group (81%, P = 0.03), the use of aortohepatic conduits did not emerge as an independent predictor of diminished graft survival via a multivariate analysis. In conclusion, in adult primary liver transplantation, the placement of an aortohepatic conduit should be strictly limited because of the greater complication rates (notably late HAT) and impaired graft survival; for children, its judicious use may be acceptable.

The pre-Kasai procedure in living donor liver transplantation for children with biliary atresia

BACKGROUND

Biliary atresia (BA) is a major cause of chronic cholestasis, a fatal disorder in infants. This study was undertaken to evaluate the safety and effectiveness of primary living donor liver transplantation (LDLT) in comparison with the traditional first-line treatment, the Kasai procedure.

METHODS

We assessed 28 children with BA at age of less than two years (3-21.3 months) who had undergone LDLT in two hospitals in Southwest China during the period of 2008-2011. Eighteen children who had had primary LDLT were included in a primary LDLT group, and ten children who had undergone the Kasai operation in a pre-Kasai group. All patients were followed up after discharge from the hospital. The records of the BA patients and donors were reviewed.

RESULTS

The time of follow-up ranged 12-44.5 months with a median of 31 months. The 30-day and 1-year survival rates were 85.7% and 78.6%, respectively. There was no significant difference in the 30-day or 1-year survival between the two groups (83.3% vs 90% and 77.8% vs 80%, P>0.05). The main cause of death was hepatic artery thrombosis. There were more patients with complications who required intensive medical care or re-operation in the pre-Kasai group (8, 80%) than in the primary LDLT group (9, 50%) (P=0.226). But no significant differences were observed in operating time (9.3 vs 8.9 hours, P=0.77), intraoperative blood loss (208.6 vs 197.0 mL, P=0.84) and blood transfusion (105.6 vs 100.0 mL, P=0.91) between the two groups. The durations of ICU and hospital stay in the primary LDLT group and pre-Kasai group were 180.4 vs 157.7 hours (P=0.18) and 27 vs 29 days (P=0.29), respectively.

CONCLUSIONS

Primary LDLT is a safe and efficient management for young pediatric patients with BA. Compared with the outcome of LDLT for patients receiving a previous Kasai operation, a similar survival rate and a low rate of re-operation and intensive medical care for patients with BA can be obtained.

Multivisceral transplantation using a 2.9 kg neonatal donor

Prematurity and very low birthweight have often been considered relative contraindications to neonatal organ donation. Organ procurement from neonatal donors is further complicated by unclear guidelines regarding neonatal brain death. We report a successful case of multivisceral transplantation using a graft from a 10-day-old, 2.9 kg, neonatal donor born at 36 6/7 wk in a 3.2 kg, three month old with intestinal and liver failure secondary to midgut volvulus. There was immediate liver graft function with correction of recipient coagulopathy, but delayed normalization of laboratory values and delayed return of bowel function. At six-yr post-transplant follow-up, the patient has normal intestine and liver function. Her last histologically confirmed rejection episode was 30 months prior to last follow-up. This case suggests that multivisceral grafts from very young or small neonatal donors may be transplanted successfully in selected cases. We propose a re-examination of the brain death guidelines for premature and young infants to potentially increase the availability of organs for infant recipients.

A formula for determining the standard liver volume in children: a special reference for neonates and infants

Accurately evaluating the ratio of GV to the SLV (GV/SLV) is important in successful pediatric liver transplantation. However, the formula used to calculate the SLV of children, including neonates and infants, has not yet been established. The aim of the current study was to estimate the SLV of children, including neonates, and to establish an accurate formula. The LV of 100 children (including 7 neonates and 15 infants) were measured using thin slice (3-5 mm) helical CT images. Their BSA was calculated from height and weight. A new formula to estimate the SLV was established as follows: SLV (mL) =689.9 × BSA (m(2)) -24.7. The SLV of children was significantly lower than that in previous reports (p < 0.001). A formula for calculating the SLV of children including neonates was established. This new formula will be useful in pediatric liver transplantation.

ABO-incompatible pediatric liver transplantation in very small recipients: Birmingham's experience

Liver transplantation (LT) for very small recipients is challenging but in experienced centres, good results can be achieved. Despite the risk of antibody-mediated acute rejection, some studies have demonstrated the safety of ABO incompatible liver transplantation (ILT) in children and particularly in infants. The aim of our study was to describe the outcome of liver transplantation in infants <5 kg and the safety of using ILT in this group. All LT performed between 1991 and 2010 in children <5 kg were reviewed. Twenty-nine patients were included, five of whom had an ILT. Acute liver failure was encountered in 20 cases. The recipient age and weight at transplantation were respectively 63 days (range: 14-268 days) and 4 kg (range: 2.4-5 kg). The graft-to-recipient ratio was 6.1% (range 2.3-9%). An aortic conduit and delayed abdominal closure were used respectively in 76% and 81% of the procedures. The ABO compatible liver transplantation (CLT) and ILT groups were similar regarding recipient's demographics, graft types or technical transplantation data. The one- and five-yr patient and graft survival were respectively 62%, 62% and 62%, 57.9% with a median follow-up of 95 months. Vascular complications occurred in six cases (21.4%) and biliary complications were encountered in five patients (17%). Acute and chronic rejection developed respectively in 37% and 26% of the recipients. The five patients undergoing ILT are all alive without graft lost after a median follow-up of 34 months (range 7-55 months). When compared with the CLT group, no significant differences were found regarding patient or graft survival, vascular or biliary complications and rejection rates. In our experience, ILT in small infants has short and long term outcomes comparable to ABO-compatible grafts and excellent results can be achieved with a standard immunosuppressive protocol. To avoid mortality on the waiting list for neonatal recipients, ABO-incompatible liver grafts can be used safely.

Liver transplantation in children weighing 5 kg or less: analysis of the UNOS database

LT is a major medical and surgical challenge in very small patients. Aim of the study is to determine the outcomes after LT in infants ≤ 5 kg at transplant in a large cohort of patients.

METHODS

Infants ≤ 5 kg who had LT between 10/1987 and 5/2008 were identified from the UNOS database. Risk factors for death and graft loss were analyzed by multivariate logistic regression.

RESULTS

Of 11,467 children, 570 (5%) were ≤ 5 kg at LT. Mean age and weight at LT were 0.11 ± 0.48 yr, 4.32 ± 0.74 kg, respectively. One- and five-yr patient and graft survival were 77.7%, 72.2% and 66.1%, 57.6%, respectively. The primary cause of death was infection (25.9%). Recipient age was a predictor of graft loss. Patient and graft survival have improved over time. Life support at transplant was identified as a risk factor for both death and graft loss (p < 0.02, p < 0.01, respectively).

CONCLUSION

LT recipients ≤5 kg have high mortality and graft loss. Over time, graft survival has improved, although it is still inferior to the overall reported outcomes of pediatric LT. Being on life support at transplant is a significant risk factor for death and graft loss in very small recipients.

Neonatal liver failure: aetiologies and management--state of the art

Acute liver failure in neonates is rare, but carries a high mortality. Neonatal liver failure can be defined as "failure of the synthetic function of liver within 4 weeks of birth". Encephalopathy is not essential for the diagnosis. Acute liver failure in neonates differs from children with regard to aetiology and outcome. Common causes of neonatal liver failure are neonatal hemochromatosis, haematological malignancies, viral infections and liver-based metabolic defects. Early diagnosis and referral to a paediatric liver centre is recommended as liver transplantation is the only definitive treatment when supportive or a disease-specific treatment fails.

Risk factors for portal vein complications in pediatric living donor liver transplantation

BACKGROUND

Portal vein (PV) complications in pediatric living donor liver transplantation (LDLT) are often asymptomatic in the early stages after transplantation and can be serious enough to lead to graft failure. There have been few reports on risk factors for PV complications in LDLT. The aim of this study is to investigate the influence of hepatic inflow upon PV complications and to predict patients at risk for these complications.

MATERIAL/METHOD

From 1997 to 2008, 46 pediatric patients underwent LDLT at our center. Portal venous and hepatic arterial flows and PV diameter were analyzed.

RESULTS

PV complications were identified in seven patients (15.2%) and occurred at a younger age and lower weight. As a result of appropriate treatment, none of the patients suffered graft failure. Analysis of the 46 patients and 27 patients under two yr of age identified smaller PV diameter in recipient and larger discrepancy of PV diameter as risk factors. Portal venous flow tended to be low, in contrast to hepatic arterial flow, which tended to be high.

CONCLUSION

PV size strongly influences PV complications. Other factors such as younger age, low portal venous flow, and high hepatic arterial flow may be risk factors for PV complications.

Living donor liver transplantation for neonates using segment 2 monosubsegment graft

The prognosis of liver transplantation for neonates with fulminant hepatic failure (FHF) continues to be extremely poor, especially in patients whose body weight is less than 3 kg. To address this problem, we have developed a safe living donor liver transplantation (LDLT) modality for neonates. We performed LDLTs with segment 2 monosubsegment (S2) grafts for three neonatal FHF. The recipient age and body weight at LDLT were 13-27 days, 2.59-2.84 kg, respectively. S2 or reduced S2 grafts (93-98 g) obtained from their fathers were implanted using temporary portacaval shunt. The recipient portal vein was reconstructed at a more distal site, such as the umbilical portion, to have the graft liver move freely during hepatic artery (HA) reconstruction. The recipient operation time and bleeding were 11 h 58 min-15 h 27 min and 200-395 mL, respectively. The graft-to-recipient weight ratio was 3.3-3.8% and primary abdominal wall closure was possible in all cases. Although hepatic artery thrombosis occurred in one case, all cases survived with normal growth. Emergency LDLT with S2 grafts weighing less than 100 g can save neonates with FHF whose body weight is less than 3 kg. This LDLT modality using S2 grafts could become a new option for neonates and very small infants requiring LT.

Successful Treatment of Biliary Atresia in Very Small Infants through Living Related Liver Transplantation

Improving outcomes in very small children is a major goal of pediatric liver transplantation. This report describes our experience of living related liver transplantation in an infant weighing 3.98 kg. The recipient, a 80-day-old male infant with congenital biliary atresia, was treated with living donor liver transplantation and then followed up for 6 months. The left lateral segment (segment II, III) with reduced size from the donor, his 26-year-old mother, was used as the graft. The graft weighed 200 g. The graft weight to recipient body weight ratio was 5.025%. The donor regained her liver function within 3 days and was discharged on day 8. The patient showed good results. Liver function returned to normal 9 days after the operation with bilirubin level almost decreased to normal. Cyclosporin, mycophenolate mofetil and prednisone were used for postoperative immunosuppression. No bleeding, thrombosis, infection or bile leakage occurred. The patient had slight fever because of a little collection in the abdomen and recovered after paracentesis and drainage. He was discharged on day 16. The donor and recipient are in satisfactory condition at present. Improvement of technique in hepatic surgery, microsurgical technique in vascular surgery and postoperative intensive care are the keys to ensure the success of the procedure.

Predictors of survival following liver transplantation in infants: a single-center analysis of more than 200 cases

BACKGROUND

Infants (<12 months) who require liver transplantation (LTx) represent a particularly challenging and understudied group of patients.

METHODS

This retrospective study aimed to describe a large single-center experience of infants who received isolated LTx, illustrate important differences in infants versus older children, and identify pretransplant factors which influence survival. More than 25 pre-LTx demographic, laboratory, and operative variables were analyzed using the Log-rank test and Cox proportional hazards model.

RESULTS

Between 1984 and 2006, 216 LTx were performed in 186 infants with a mean follow-up time of 62 months. Median age at LTx was 9 months, the majority had cholestatic liver disease, were hospitalized pre-LTx, and received whole grafts. Leading indications for re-LTx (n=30) included vascular complications (43%) and graft nonfunction (40%), whereas leading causes of death were sepsis and multiorgan failure. One-, 5-, and 10-year graft and patient survivals were 75%/72%/68% and 79%/77%/75%, respectively. Relative to older pediatric recipients, infants had worse overall patient survival (P=0.05). The following were significant univariate predictors of graft loss: age less than 6 months and reduced cadaveric grafts; and of patient loss: age less than 6 months, calculated CrCl less than 90, pre-LTx hospitalization, pre-LTx mechanical ventilation, repeat LTx, infants transplanted for reasons other than cholestatic liver disease, and patients transplanted between 1984 and 1994.

CONCLUSIONS

Long-term outcomes for infants undergoing LTx are excellent and have improved over time. As the largest, single-center analysis of LTx in infants, this study elucidates a unique set of predictors that can aid in medical decision making.

Early orthotopic liver transplantation in urea cycle defects: follow up of a developmental outcome study

Patients with neonatal urea cycle defects (UCDs) typically have high mortality and poor neurological outcome unless they receive liver transplantation. Neurologic outcome may be better with liver transplantation before age one year. We report on a follow up on an initial prospective study performed to assess developmental outcome after early liver transplant using the Griffiths Scales. Developmental testing up to 7years after transplantation showed average developmental quotients (DQs) of 69 for four children who underwent transplantation before one year of age (latest DQs were 47, 63, 95 and 96), and 80 for a patient who underwent transplantation at 3years of age (latest DQ was 88). We conclude that a combination of early liver transplantation, aggressive metabolic management and early childhood intervention improve the neurologic outcome of children with UCDs.

Emergency liver transplantation in neonates with acute liver failure: long-term follow-up

BACKGROUND

Acute neonatal liver failure is a rare condition that is often fatal. Liver transplantation (LTx) in affected neonates may be life saving, but there are only few data on the long-term outcome of neonatal LTx.

PATIENTS AND METHODS

We conducted a retrospective study of 11 LTx performed in 10 pediatric patients with acute liver failure in the first month of life. Median age at LTx was 15 days (range: 7-31 days) and median weight was 3.25 kg (range: 2-4 kg). The reasons for liver failure were neonatal hemochromatosis (n=5), hemangioendothelioma (n=2), infection caused by echovirus type 11 (n=1), mitochondrial disorder (n=1), unknown (n=1), and primary nonfunction after LTx (n=1). In 10 patients, LTx organs of deceased donors were used (reduced size n=5, split n=5), and living donor LTx was performed in one neonate. The patients were evaluated with respect to survival, graft function, perioperative complications, and neurodevelopmental outcome.

RESULTS

After a median follow-up time of 5 years (range: 1-14 years), 8 of 10 patients (80%) were alive. Seven of them were in good clinical condition and had normal liver function tests. One patient had to undergo retransplantation because of primary nonfunction and another is currently listed for retransplantation because of chronic graft dysfunction. Neurodevelopment was normal in 75% of the surviving patients.

CONCLUSIONS

Liver transplantation provides good short- and medium-term results in neonatal acute liver failure.

Experimental models of hepatectomy and liver regeneration using newborn and weaning rats

OBJECTIVES

Liver regeneration is a complex process that has not been completely elucidated. The model most frequently used to study this phenomenon is 70% hepatectomy in adult rats; however, no papers have examined this effect in developing animals. The aims of the present study were: 1) to standardize two models of partial hepatectomy and liver regeneration in newborn suckling and weaning rats, and 2) to study the evolution of remnant liver weight and histological changes of hepatic parenchyma on the days that follow partial hepatectomy.

METHODS

Fifty newborn and forty-four weaning rats underwent 70% hepatectomy. After a midline incision, compression on both sides of the upper abdomen was performed to exteriorize the right medial, left medial and left lateral hepatic lobes, which were tied inferiorly and resected en bloc. The animals were sacrificed on days 0 (just after hepatectomy), 1, 2, 3, 4 and 7 after the operation. Body and liver weight were determined, and hepatic parenchyma was submitted to histological analysis.

RESULTS

Mortality rates of the newborn and weaning groups were 30% and 0%, respectively. There was a significant decrease in liver mass soon after partial hepatectomy, which completely recovered on the seventh day in both groups. Newborn rat regenerating liver showed marked steatosis on the second day. In the weaning rat liver, mitotic figures were observed earlier, and their amount was greater than in the newborn.

CONCLUSIONS

Suckling and weaning rat models of partial hepatectomy are feasible and can be used for studies of liver regeneration. Although similar, the process of hepatic regeneration in developing animals is different from adults.