Long-term outcomes after liver transplantation in children

Recent advances in surgical strategies and liver transplantation for hepatoblastoma

Hepatoblastoma (HB) is the most common malignant liver tumor in children. Although the development of treatment strategies with advances in chemotherapy has greatly improved the prognosis of HB, surgical resection and liver transplantation still play a vital role in the treatment of HB. In recent years, technological innovations have led to the development of new surgical approaches for HB. In this review, we describe the latest research on the surgical management of HB, including new imaging technologies, minimally invasive approaches, and the application of associating liver partition portal vein ligation for staged hepatectomy. We also discuss the current role of liver transplantation, use of ante-situm or ex-situ liver resection with auto-transplantation, and management of metastatic HB.

Outcomes following liver transplantation in young infants: Data from the SPLIT registry

Liver transplantation (LT) in young patients is being performed with greater frequency. We hypothesized that objective analysis of pre-, intra-, and postoperative events would help understand contributors to successful outcomes and guide transplant decision processes. We queried SPLIT registry for pediatric transplants between 2011 and 2018. Outcomes were compared for age groups: 0-<3, 3-<6, 6-<12 months, and 1-<3 years (Groups A, B, C, D respectively) and by weight categories: <5, 5-10, >10 kg; 1033 patients were available for analysis. Cholestatic disease and fulminant failure were highest in group A and those <5 kg; and biliary atresia in group C (72.8%). Group A had significantly higher life support dependence (34.6%; P < .001), listing as United Network for Organ Sharing status 1a/1b (70.4%; P < .001), and shortest wait times (P < .001). The median (interquartile range) for international normalized ratio and bilirubin were highest in group A (3.0 [2.1-3.9] and 16.7 [6.8-29.7] mg/dL) and those <5 kg (2.6 [1.8-3.4] and 13.5 [3.0-28.4] mg/dL). A pediatric end -stage liver disease score ≥40, postoperative hospital stays, rejection, and nonanastomotic biliary strictures were highest in group A with lowest survival at 93.1%. Infants 0 to <3 months and those <5 kg need more intensive care with lower survival and higher complications. Importantly, potential LT before reaching status 1a/1b and aggressive postoperative management may positively influence their outcomes.

Adherence to medical regimen after pediatric liver transplantation: a systematic review and meta-analysis

PURPOSE

Adherence to the medical regimen after pediatric liver transplantation is crucial for good clinical outcomes. However, the existing literature provides inconsistent evidence regarding the prevalence of and risk factors for nonadherence to the medical regimen after pediatric liver transplantation. This study aimed to investigate such nonadherence after pediatric liver transplantation and risk factors associated with this nonadherence using findings of reported studies.

METHODS

The electronic databases of Excerpta Medica, Ovid Technologies, PubMed and WanFang Data were searched using the keywords "adherence", "liver transplant" and "paediatric". Additionally, relevant references cited in related studies were used to obtain original articles. Using 22 original articles, data regarding nonadherence to the medical regimen after pediatric liver transplantation were quantitatively combined, and risk factors associated with nonadherence were qualitatively identified. Average rates of nonadherence in four areas of medical regimens were calculated. The heterogeneity of the included original articles was also analyzed. When I ²>50 and P<0.05, a random effects model was used; otherwise, a fixed effects model was used. Moreover, Egger's and Begg's tests were used to evaluate publication bias, if any, and original articles with P>0.05 were considered to have no publication bias.

RESULTS

The clinical attendance nonadherence rate was 45% (95% confidence interval [CI]: 39-51), global nonadherence rate was 17% (95% CI: 13-21) and immunosuppression non-adherence rates were 39% (95% CI: 26-52) and 34% (95% CI: 30-39) for cyclosporine and tacrolimus, respectively. Risk factors included older age of the pediatric patient, low family cohesion, poor social functioning, poor mental health and single-parent family.

CONCLUSIONS

The nonadherence rate in pediatric liver transplantation is high. Therefore, intervention on the basis of risk factors, such as mental health and family function, may be necessary. Moreover, a standard technique for assessing nonadherence to the medical regimen after pediatric liver transplantation, comprising as many dimensions as possible, is required in order to be more objective and comprehensive when assessing nonadherence.

Technology and vascularized composite allotransplantation (VCA)-lessons learned from the first bilateral pediatric hand transplant

The reconstructive principle of replacing "like with like" is best met with vascularized composite allotransplantation in which the components of an existing defect are "matched" to the greatest extent possible in a single stage restoration. Hand transplantation is a labor-intensive and time-intensive process and can be conceptualized into distinct phases that include (1) patient selection and preoperative preparation, (2) technical execution of the procedure, and (3) postoperative rehabilitation and follow-up. The advent of technological innovations, such as 3D printing technology, novel implant technology, as well as innovative imaging technology, such as functional magnetic resonance imaging have the potential of favorably affecting all phases of this process, thus contributing to improved outcomes. The use of these technologies in the world's first case of bilateral hand transplantation in a pediatric patient is discussed.

Longterm outcomes of auxiliary partial orthotopic liver transplantation in preadolescent children with fulminant hepatic failure

By preserving part of the native liver, auxiliary partial orthotopic liver transplantation (APOLT) provides the advantage of potential immunosuppression (ISP) withdrawal if the native liver recovers but has had limited acceptance, especially in the United States, due to technical complications and low rates of native liver regeneration. No previous study has evaluated APOLT specifically for preadolescent children with fulminant hepatic failure (FHF). This population might benefit especially based on greater capacity for liver regeneration. Data from 13 preadolescent children who underwent APOLT were compared to 13 matched controls who underwent orthotopic liver transplantation (OLT) for FHF from 1996 to 2013. There were no significant differences in patient demographics or survival between the 2 groups. However, all surviving OLT recipients (10/13) remain on ISP, while all but 1 surviving APOLT recipient (12/13) showed native liver regeneration, and the first 10 recipients (76.9%) are currently off ISP with 2 additional patients currently weaning. In our experience, APOLT produced excellent survival and high rates of native liver regeneration in preadolescent children with FHF. This represents the largest series to date to report such outcomes. Liberating these children from lifelong ISP without the downside of increased surgical morbidity makes APOLT an attractive alternative. In conclusion, we therefore propose that, with the availability of technical expertise and with the technical modifications above, APOLT for FHF should be strongly considered for preteenage children with FHF.

A common peripheral blood gene set for diagnosis of operational tolerance in pediatric and adult liver transplantation

To identify biomarkers of operational tolerance in pediatric and adult liver transplant recipients, transcriptional profiles were examined from 300 samples by microarrays and Q-PCR measurements of blood specimens from pediatric and adult liver transplant recipients and normal tissues. Tolerance-specific genes were validated in independent samples across two different transplant programs and validated by Q-PCR. A minimal set of 13 unique genes, highly expressed in natural killer cells (p = 0.03), were significantly expressed in both pediatric and adult liver tolerance, irrespective of different clinical and demographic confounders. The performance of this gene set by microarray in independent samples was 100% sensitivity and 83% specificity and the AUC was 0.988 for only three genes by Q-PCR. 26% of adults and 64% of children with excellent liver allograft function, on minimal or dual immunosuppression, showed high prediction scores for tolerance. Novel peripheral transcriptional profiles can be identified in operational tolerance in pediatric and adult recipients of liver allografts, suggesting a high incidence of a pro-tolerogenic phenotype in stable patients on chronic immunosuppression. Given the high incidence of viral infections and malignancies in liver transplant recipients, this gene set provides an important monitoring tool that can move the field toward personalized and predictive medicine in organ transplantation.

Successful treatment of unresectable advanced hepatoblastoma: living liver transplantation after surgical removal of lung metastasis

Hepatoblastoma is a rare malignant tumor of the liver in children. Intensive combination chemotherapy has increased the number of surgically resectable cases and improved prognosis markedly. However, unresectable cases and cases with residual metastasis, including lung metastases, have a poor prognosis. In these refractory cases, treatment strategy has not been established. On the other hand, living liver transplantation has been shown to be effective in cases of advanced hepatoblastoma, but its effectiveness in cases with residual distant metastases after chemotherapy remains unclear. We report one successful case of advanced unresectable hepatoblastoma with multiple lung metastases. Intensive chemotherapy consisting of high-dose chemotherapy with autologous hematopoietic stem cell transplantation was not effective. We performed living liver transplantation after surgical resection of residual lung metastases, which were histologically viable. After liver transplantation, the level of tumor marker decreased gradually. The patient experienced no severe complications. This case suggested that living liver transplantation could be effective in cases of advanced refractory hepatoblastoma after control of distant metastases.

Psychiatric issues in pediatric organ transplantation

Solid organ transplantation has become the first line of treatment for a growing number of life-threatening pediatric illnesses. With improved survival, research into the long-term outcome of transplant recipients has become important to clinicians. Adherence to medical instructions remains a challenge, particularly in the adolescent population. New immunosuppressant approaches promise to expand organ transplantation in additional directions. Extension of transplantation into replacement of organs such as faces and hands raises complex ethical issues.

One thousand consecutive primary liver transplants under tacrolimus immunosuppression: a 17- to 20-year longitudinal follow-up

BACKGROUND

Tacrolimus has proven to be a potent immunosuppressive agent in orthotopic liver transplantation (OLT). The aim of this study is to examine its long-term efficacy and safety.

METHODS AND RESULTS

One thousand consecutive primary OLTs performed between August 1989 and December 1992 and maintained under tacrolimus-based immunosuppression were followed up until January 2009. Patient and graft survivals with corresponding causes of death and retransplantation, maintenance immunosuppression, and adverse effects were examined. The study population includes 600 males and 400 females comprising 166 children, 630 adults, and 204 seniors. The mean follow-up was 17.83 (range, 16.1-19.50) years. The overall 20-year actuarial patient and graft survivals were 35.8% and 32.6%, respectively. At the last follow-up, 442 patients were alive; 133 (77.1%) children, 265 (34.5%) adults, and 44 (16.1%) seniors (P=0.0001). After the first post-OLT year, cardiopulmonary events, recurrence of primary disease, and malignancy were the main causes of death. Overall, 183 recipients underwent retransplants; mainly for primary nonfunction, hepatic artery thrombosis, and recurrent primary disease, 180 required dialysis, and 45 underwent kidney transplant. A total of 97.7% of the survivors were on tacrolimus and 26.2% were also receiving adjunctive immunosuppressants at the last follow-up.

CONCLUSIONS

The overall 20-year actuarial patient and graft survivals were 35.8% and 32.6%, respectively, with significantly better survival among children. Age-related complications, recurrence of primary disease, and malignancy were the major causes of late graft loss. Graft loss related to immunologic reasons was rare. The prevention of recurrent disease and newer immunosuppressive regimen will further improve these results.

Microvillous inclusion disease: how to improve the prognosis of a severe congenital enterocyte disorder

BACKGROUND AND OBJECTIVE

Microvillous inclusion disease (MVID) is a rare congenital enterocyte disorder causing severe diarrhea and intestinal failure. The objective of this study was to analyze clinical evolution and the most frequent complications of MVID in children receiving parenteral nutrition (PN) and after small-bowel transplantation (SBTx) with the aim to improve treatment strategies and prognosis.

PATIENTS AND METHODS

From 1995 to 2009, 24 patients (16 boys, median follow-up 4.7 years, range: from birth to 23.5 years) with MVID were admitted to our unit. The recorded parameters included growth, neurological development, liver and renal functions, bone disease, and outcome.

RESULTS

Almost half of the children were from consanguineous families from the Mediterranean area. All of the patients completely depended on PN. Four children died of PN complications before 4 years of age. Before or without SBTx, growth failure was common (mean height -2.5 standard deviations [SD]), as was developmental delay (12/24), liver (20/22 with fibrosis) or kidney disease (3/23 with moderate renal insufficiency), and osteoporosis (6/24). Thirteen children underwent SBTx (9 isolated, 4 combined with liver Tx) at a median age of 3.5 years. Follow-up after SBTx was 0.4 to 14 years. Patient survival rates were 63% without SBTx and 77% with SBTx. After SBTx, 4 children experienced catch-up growth.

CONCLUSIONS

PN in MVID is difficult to manage and requires expertise. Despite improved results in expert centers, the risk of death or irreversible sequelae is higher with PN than after Tx. SBTx, despite being complicated, remains the only hope to improve the quality of life and long-term prognosis of these children.

Psychiatric issues in pediatric organ transplantation

Solid organ transplantation has become the first line of treatment for a growing number of life-threatening pediatric illnesses. With improved survival, research into the long-term outcome of transplant recipients has become important to clinicians. Adherence to medical instructions remains a challenge, particularly in the adolescent population. New immunosuppressant approaches promise to expand organ transplantation in additional directions. Extension of transplantation into replacement of organs such as faces and hands raises complex ethical issues.

Long-term outcomes in pediatric liver transplantation

1. Critical clinical outcomes for pediatric liver transplantation (LT) recipients include (1) patient and graft survival, (2) complications (immune and nonimmune) of chronic immunosuppressive medications, and (3) long-term graft function. 2. Recurrence of malignancy, sepsis, and posttransplant lymphoproliferative disorder account for more than 65% of deaths occurring more than 1 year after LT. 3. Chronic rejection, late hepatic artery thrombosis, and biliary strictures account for 70% of graft loss occurring more than 1 year after LT. 4. Late histological changes in the allograft are emerging as a common problem in patients more than 5 years after LT. The pathogenesis of these findings and the impact on graft survival remain to be determined.

Meta-analysis of medical regimen adherence outcomes in pediatric solid organ transplantation

BACKGROUND

Adherence to the medical regimen after pediatric organ transplantation is important for maximizing good clinical outcomes. However, the literature provides inconsistent evidence regarding prevalence and risk factors for nonadherence posttransplant.

METHODS

A total of 61 studies (30 kidney, 18 liver, 8 heart, 2 lung/heart-lung, and 3 with mixed recipient samples) were included in a meta-analysis. Average rates of nonadherence to six areas of the regimen, and correlations of potential risk factors with nonadherence, were calculated.

RESULTS

Across all types of transplantation, nonadherence to clinic appointments and tests was most prevalent, at 12.9 cases per 100 patients per year (PPY). The immunosuppression nonadherence rate was six cases per 100 PPY. Nonadherence to substance use restrictions, diet, exercise, and other healthcare requirements ranged from 0.6 to 8 cases per 100 PPY. Only the rate of nonadherence to clinic appointments and tests varied by transplant type: heart recipients had the lowest rate (4.6 cases per 100 PPY vs. 12.7-18.8 cases per 100 PPY in other recipients). Older age of the child, family functioning (greater parental distress and lower family cohesion), and the child's psychological status (poorer behavioral functioning and greater distress) were among the psychosocial characteristics significantly correlated with poorer adherence. These correlations were small to modest in size (r=0.12-0.18).

CONCLUSIONS

These nonadherence rates provide benchmarks for clinicians to use to estimate patient risk. The identified psychosocial correlates of nonadherence are potential targets for intervention. Future studies should focus on improving the prediction of nonadherence risk and on testing interventions to reduce risk.

De novo bile salt transporter antibodies as a possible cause of recurrent graft failure after liver transplantation: a novel mechanism of cholestasis

Progressive familial intrahepatic cholestasis type 2 (PFIC-2) is caused by mutations of the bile salt export pump (BSEP [ABCB11]), an ATP-binding cassette (ABC)-transporter exclusively expressed at the canalicular membrane of hepatocytes. An absence of BSEP from the canalicular membrane causes cholestasis and leads to liver cirrhosis, which may necessitate liver transplantation in early childhood. We report on the first case of a child with PFIC-2 suffering from repeated posttransplant recurrence of progressive intrahepatic cholestasis due to autoantibodies against BSEP. These antibodies occurred after transplantation and were detected in the patient's serum and at the canalicular membrane of two consecutive liver transplants. The antibodies were reactive toward the first extracellular loop of BSEP, were of high affinity, and inhibited transport activity of BSEP, thus causing severe cholestasis. The patient had three homozygous, missense changes in the BSEP gene. Their combination resulted in the complete absence of BSEP, which explains the lack of tolerance, a prerequisite of autoantibody formation toward BSEP. The findings illustrate a novel disease mechanism due to a new class of functionally relevant autoantibodies resulting in cholestasis and subsequent liver failure.