Recipient-Specific Risk Factors Impairing Patient and Graft Outcome after Pediatric Liver Transplantation-Analysis of 858 Transplantations in 38 Years

Gastric sleeve as an extra-anatomical roux for biliary reconstruction in a pediatric third liver transplant

BACKGROUND

Sir Roy Calne in 1976 described "Biliary reconstruction is the Achilles heel of liver transplantation," and it remains true. In some patients, such as those with short-gut syndrome and concomitant biliary atresia, neither duct to duct nor Roux biliary reconstruction is feasible.

METHODS

We present a case of child's third liver transplant (LT), where an innovative extra-anatomical biliary bypass was created using a sleeve from greater curvature of the stomach.

RESULTS

The patient is well nearly 10 years following the LT.

CONCLUSIONS

This technique could prove to be an important addition to the armamentarium of a surgeon in difficult retransplants and in patients with short-gut syndrome as it provides a viable option with good long-term outcome.

Diminished measles immunity after paediatric liver transplantation-A retrospective, single-centre, cross-sectional analysis

Liver transplantation in childhood has an excellent long-term outcome, but is associated with a long-term risk of infection. Measles is a vaccine-preventable infection, with case series describing severe courses with graft rejection, mechanical ventilation and even death in liver transplant recipients. Since about 30% of liver transplanted children receive liver transplants in their first year of life, not all have reached the recommended age for live vaccinations. On the contrary, live vaccines are contraindicated after transplantation. In addition, vaccination response is poorer in individuals with liver disease compared to healthy children. This retrospective, single-centre, cross-sectional study examines measles immunity in paediatric liver transplant recipients before and after transplantation. Vaccination records of 239 patients, followed up at Hannover Medical School between January 2021 and December 2022 were analysed. Twenty eight children were excluded due to stem cell transplantation, regular immunoglobulin substitution or measles vaccination after transplantation. More than 55% of all 211 children analysed and 75% of all those vaccinated at least once are measles seropositive after transplantation-48% after one and 84% after two vaccinations-which is less than in healthy individuals. Interestingly, 26% of unvaccinated children also showed measles antibodies and about 5-15% of vaccinated patients who were seronegative at the time of transplantation were seropositive afterwards, both possibly through infection. In multivariable Cox proportional hazards regression, the number of vaccinations (HR 4.30 [95% CI 2.09-8.83], p<0.001), seropositivity before transplantation (HR 2.38 [95% CI 1.07-5.30], p = 0.034) and higher age at time of first vaccination (HR 11.5 [95% CI 6.92-19.1], p<0.001) are independently associated with measles immunity after transplantation. In contrast, older age at testing is inversely associated (HR 0.09 [95% CI 0.06-0.15], p<0.001), indicating a loss of immunity. Vaccination in the first year of life does not pose a risk of non-immunity. The underlying liver disease influences the level of measles titres of twice-vaccinated patients; those with acute liver failure being the lowest compared to children with metabolic disease. In summary, vaccine response is poorer in children with liver disease. Liver transplant candidates should be vaccinated before transplantation even if this is earlier in the first year of life. Checking measles IgG and re-vaccinating seronegative patients may help to achieve immunity after transplantation.

Liver transplantation for pediatric patients with congenital heart disease: A single-center study in mainland China

BACKGROUND

Liver transplantation (LT) is a serious cardiovascular stressor for patients with end-stage liver disease (ESLD). Data on the effects of cardiovascular diseases on pediatric LT is limited. No study on LT for pediatric patients with ESLD combined with congenital heart disease (CHD) has been reported from mainland China.

METHODS

A total of 1005 patients were included in this study. The Kaplan-Meier method with log-rank testing was used to evaluate survival outcomes between groups. Univariable and multivariable Cox regression models were used to determine the risk factors for patient and graft survival.

RESULTS

The most common indication for LT was biliary atresia (BA 90.3%). The prevalence of CHD was 3.8% (38). 42 CHD were found in 38 patients. The incidence of death and graft loss was more common in the CHD group than in the no-CHD group (13.2% vs. 5.0%, p = .045 and 15.8% vs. 6.2%, p = .019, respectively). The 5-year patient survival and graft survival in the CHD group versus the no-CHD group was 86.8% versus 94.7% (log-rank p = .022) and 84.2% versus 93.5% (log-rank p = .015), respectively. No significant differences were observed in re-transplantation, hepatic artery thrombosis (HAT), and portal vein thrombosis (PVT). After adjusting for age, BMI, etiology of LT, and other confounding factors, we can still find that the presence of CHD was associated with patient and graft survival after LT.

CONCLUSION

The presence of CHD was associated with higher mortality and lower graft survival after LT. If possible, the cardiac defects should be addressed prior to LT.

Global research on portal vein thrombosis and liver transplantation: A bibliometric and visualized study

In recent years, the association between portal vein thrombosis and liver transplantation has extensive attention from physicians worldwide. However, there is no available literature on bibliometric analysis in this research area. Herein, we aimed to conduct a bibliometric analysis to identify the hotspots and frontiers of research related to portal vein thrombosis and liver transplantation. Documents published between 2002 and 2022 were retrieved and downloaded from the Web of Science Core Collection database. VOSviewer was utilized to generate a visualization network map of authors, nations, institutions, journals, and keyword co-occurrence/clustering. Additionaly, CiteSpace was used to analyze the keywords with the strongest bursts. A total of 1272 articles and reviews were extracted from the database. The author Marco Senzolo published the largest number of papers. The United States was the most prolific country, and Hope-Bochon (France) was the top productive institution. Liver Transplantation was the most prolific journal in the field. The most commonly identified keywords in the study were cirrhosis, risk factors, portal vein thrombosis, and management, as revealed by the keyword co-occurrence analysis. It is suggested that patients with cirrhosis, portal vein thrombosis prevention, and management measures for portal vein thrombosis have been prominet topics in recent years. Furthermore, an analysis of keywords with the strongest citation bursts highlighted pediatric liver transplantation, direct oral anticoagulants, and nonalcoholic fatty liver disease as current research trends. Research in portal vein thrombosis and liver transplantation exhibits a general upward trend. The latest hot topics within this area of study involve pediatric patients and nonalcoholic fatty liver disease.

Long-Term Outcome Following Liver Transplantation for Primary Hepatic Tumors-A Single Centre Observational Study over 40 Years

The incidence of pediatric liver tumors in general has been rising over the last years and so is the number of children undergoing liver transplantation for this indication. To contribute to the ongoing improvement of pre- and post-transplant care, we aim to describe outcome and risk factors in our patient cohort. We have compared characteristics and outcome for patients transplanted for hepatoblastoma to other liver malignancies in our center between 1983 and 2022 and analysed influential factors on tumor recurrence and mortality using nominal logistic regression analysis. Of 39 children (16 f) who had transplants for liver malignancy, 31 were diagnosed with hepatoblastoma. The proportion of malignant tumors in the transplant cohort rose from 1.9% (1983-1992) to 9.1% in the current decade (p < 0.0001). Hepatoblastoma patients were transplanted at a younger age and were more likely to have tumor extent beyond the liver. Post-transplant bile flow impairment requiring intervention was significantly higher compared to our total cohort (48 vs. 24%, p > 0.0001). Hearing loss was a common side effect of ototoxic chemotherapy in hepatoblastoma patients (48%). The most common maintenance immunosuppression were mTor-inhibitors. Risk factors for tumor recurrence in patients with hepatoblastoma were higher AFP before transplant (AFP_pre-LTX), a low ratio of AFP_max to AFP_pre-LTX and salvage transplantation. Liver malignancies represent a rising number of indications for liver transplantation in childhood. Primary tumor resection can spare a liver transplant with all its long-term complications, but in case of tumor recurrence, transplantation might have inferior outcome. The rate of acute biopsy-proven rejections and biliary complications in comparison to our total transplant cohort needs further investigations.

Acute severe non-A-E-hepatitis of unknown origin in children - A 30-year retrospective observational study from north-west Germany

BACKGROUND & AIMS

The etiology of the current acute severe non-A-E hepatitis epidemic in children remains unclear. We aimed to describe the occurrence and outcomes of acute severe hepatitis in pediatric patients in North-West Germany over a period of more than 30 years and in the context of the current epidemic.

METHODS

We analyzed all cases of acute severe hepatitis in childhood, as defined by the World Health Organization, at Hannover Medical School from 1990 and at the University Hospital of Essen from 2009 to 16 May 2022. We separated cases into a historic cohort (1990-2018) and a COVID-19 era cohort (2019-2022).

RESULTS

After application of exclusion criteria, 107 patients with acute severe hepatitis were identified (2.32 cases/center/year). Annual incidence per center rose significantly from 2.2 (historic cohort until 2018) to 4.25/center/year (from 2019, p = 0.002). Of all cases, 75.7% presented with jaundice, while 53.3% had clinical signs of infection. Two cases of adenovirus were proven (2004/2016), other pathogens detected were HHV-6 (4), CMV, HSV, EBV(3). Sixty-nine patients (64.5%) met the criteria of pediatric acute liver failure, with 44 requiring liver transplantation. In the current cohort, patients with infection, gastrointestinal symptoms and higher alanine aminotransferase had a better chance of transplant-free survival, whereas hepatic encephalopathy, higher international normalized ratio and bilirubin predicted a poor outcome. Twenty-five patients developed hepatitis-associated aplastic anemia and 19 patients (17.8%) died.

CONCLUSIONS

Acute non-A-E-hepatitis in children is a rare but severe entity, often leading to acute liver failure. Clinical presentation in our current cohort resembles 2022 NAEH cases, with improved outcomes compared to historic controls. The rising incidence of NAEH in our centers since 2019, in the absence of adenoviral infection, indicates other potential triggers of similar NAEH cases.

IMPACT AND IMPLICATIONS

As the current epidemic of severe acute non-A-E-hepatitis cases in children highlights our limited understanding in the field, we aim to describe current cases, characterizing the presentation over time, and defining similarities and discrepancies before and during the COVID-19 pandemic. Our data show a rising incidence of non-A-E-hepatitis cases since the beginning of the COVID-19 pandemic. These cases were not associated with adenoviral infections, suggesting that the recently described accumulation of adenovirus infections in relationship to hepatitis is a new trigger for a known phenomenon, rather than a new disease entity. Therefore, the role of protective isolation and subsequent lack of contact with trivial infections in children during the pandemic should be the subject of further examinations. We expect our data to contribute to a better understanding of severe acute hepatitis in childhood, increased vigilance for this potentially lethal disease beyond the current epidemic, and ultimately improved clinical diagnosis and care.

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.

Hepatitis A Immunity and Paediatric Liver Transplantation-A Single-Centre Analysis

Following paediatric solid organ liver transplantation, risk of infection is high, both in the short and long term. Even though an infection with hepatitis A virus (HAV) is often asymptomatic and self-limited in children, some case studies describe severe cases leading to death. Vaccinations offer simple, safe and cheap protection. However, data on vaccination rates against hepatitis A in children with liver disease are scarce. Moreover, the vaccine is only approved from the age of one year old. At the same time, up to 30% of children with liver disease are transplanted within the first year of life, so the window of opportunity for vaccination is limited. This retrospective, observational, single-centre study examines the HAV immunity in paediatric liver transplant recipients before and after the first year of transplantation. Vaccination records of 229 of 279 (82.1%) children transplanted between January 2003 and June 2021 were analysed. Of 139 eligible children aged ≥ 1 year old, only 58 (41.7%) were vaccinated at least with one HAV dose prior to transplantation. In addition, seven patients received the vaccine below one year of age. After one or two doses, 38.5% or 90.6% of 65 patients were anti-HAV-IgG positive, respectively. This percentage remained stable up to the first annual check-up. For children vaccinated only once, a shorter interval from vaccination to transplantation is a risk factor for lack of immunity. Thus, HAV immunisation should be started earlier in liver transplant candidates to improve immunity in this high-risk group.

Cold Ischemia Time and Graft Fibrosis Are Associated with Autoantibodies after Pediatric Liver Transplantation: A Retrospective Cohort Study of the European Reference Network TransplantChild

The reported prevalence of autoantibodies (AAB) (ANA, SMA, LKM, SLA) after pediatric liver transplantation (pLTX) varies considerably from 26–75%, but their clinical impact on outcome is uncertain. We aimed to study the prevalence of AAB after pLTX, their association with donor-, transplant-, and recipient-characteristics, and their relation to outcome. In our multicenter retrospective study, we aimed to clarify conflicting results from earlier studies. Six ERN TransplantChild centers reported data on 242 patients, of whom 61% were AAB positive. Prevalence varied across these centers. Independent of the interval between pLTX and AAB analysis, a one-hour increase in CIT resulted in an odds ratio (OR) of 1.37 (95% CI 1.11–1.69) for SMA positivity and an OR of 1.42 (95%CI 1.18–1.72) for ANA positivity. Steroid-free immunosuppression (IS) versus steroid-including IS (OR 5.28; 95% CI 1.45–19.28) was a risk factor for SMA positivity. Liver enzymes were not associated with ANA or SMA positivity. We did not observe an association of rejection activity index with ANA or SMA. However, the liver fibrosis score in follow-up biopsies was associated with ANA titer and donor age. In conclusion, this first multicenter study on AAB after pLTX showed high AAB prevalence and varied widely between centers. Longer CIT and prednisolone-free-IS were associated with AAB positivity, whereas AAB were not indicative of rejection, but instead were associated with graft fibrosis. The detection of AAB may be a marker of liver fibrosis and may be taken into consideration when indications for liver biopsy and immunosuppressive regimes, or reduction of immunosuppression in long-term follow-up, are being discussed. Prospective immunological profiling of pLTX patients, including AAB, is important to further improve our understanding of transplant immunology and silent graft fibrosis.

Long-Term Varicella Zoster Virus Immunity in Paediatric Liver Transplant Patients Can Be Achieved by Booster Vaccinations—A Single-Centre, Retrospective, Observational Analysis

Varicella is one of the most common vaccine-preventable infections after paediatric solid organ transplantation; thus, vaccination offers simple and cheap protection. However, children with liver disease often progress to liver transplantation (LT) before they reach the recommended vaccination age. As a live vaccine, varicella zoster virus (VZV) vaccination after transplantation is controversial; however, many case series demonstrate that vaccination may be safe and effective in paediatric liver transplant recipients. Only limited data exists describing long-term vaccination response in such immunocompromised patients. We investigated retrospectively vaccination response in paediatric patients before and after transplantation and describe long-term immunity over ten years, including the influence of booster-vaccinations. In this retrospective, single-centre study, 458 LT recipients were analysed between September 2004 and June 2021. Of these, 53 were re-transplantations. Patients with no available vaccination records and with a history of post-transplant lymphoproliferative disease, after hematopoietic stem cell transplantation and clinical chickenpox were excluded from this analysis (n = 198). In total, data on 207 children with a median annual follow-up of 6.2 years was available: 95 patients (45.9%) were unvaccinated prior to LT. Compared to healthy children, the response to vaccination, measured by seroconversion, is weaker in children with liver disease: almost 70% after one vaccination and 93% after two vaccinations. One year after transplantation, the mean titres and the number of children with protective antibody levels (VZV IgG ≥ 50 IU/L) decreased from 77.5% to 41.3%. Neither diagnosis, gender, nor age were predictors of vaccination response. Booster-vaccination was recommended for children after seroreversion using annual titre measurements and led to a significant increase in mean titre and number of protected children. Response to vaccination shows no difference from monotherapy with a calcineurin inhibitor to intensified immunosuppression by adding prednisolone or mycophenolate mofetil. Children with liver disease show weaker seroconversion rates to VZV vaccination compared to healthy children. Therefore, VZV-naïve children should receive basic immunization with two vaccine doses as well as those vaccinated only once before transplantation. An average of 2–3 vaccine doses are required in order to achieve a long-term seroconversion and protective antibody levels in 95% of children.