Failure to Rescue Pediatric Recipients of Living Donor Liver Transplantation: A Single-Center Study of Technical Complications in 500 Primary Grafts.

BACKGROUND: The concept of failure to rescue (FTR) has been used to evaluate the quality of care in several surgical specialties but has not been well-studied after living donor liver transplantation (LDLT) in children. METHODS: This study retrospectively reviewed 500 pediatric LDLT performed at a single center between 1993 and 2022. The recipient outcomes were assessed by means of patient and graft survival rates, retransplantation rates, and arterial/portal/biliary complication rates. Graft and patient losses secondary to these complications were calculated regarding FTR for patients (FTRp) and grafts (FTRg). RESULTS: Overall 1- and 5-year patient survival rates were 94.5% and 92.1%, respectively, the corresponding figures for graft survival being 92.7% and 89.8%. One-year hepatic artery complication rate was 3.6% (n = 18 cases), the respective rates for portal vein complications and biliary complications being 5.7% (n = 57) and 15.6% (n = 101). One-year FTRp rates for hepatic artery thrombosis, portal vein thrombosis, anastomotic biliary stricture, and intrahepatic biliary stricture were 28.6%, 9.4%, 3.6%, and 0%, respectively. The corresponding FTRg rates being 21.4%, 6.3%, 0%, and 36.4%. CONCLUSION: Such novel analytical method may offer valuable insights for optimizing quality of care in pediatric LDLT.

Nasobiliary drainage prior to surgical biliary diversion in progressive familial intrahepatic cholestasis type II.

Progressive familial intrahepatic cholestasis (PFIC) can cause intense pruritus that is refractory to medical therapy. Surgical biliary diversion techniques, including partial internal biliary diversion (PIBD), have been developed over the years to relieve pruritus without requiring liver transplantation. No clinical or genetic features can currently predict postoperative pruritus response. We present three PFIC type 2 (PIFC 2) patients who underwent transient endoscopic nasobiliary drainage (NBD) prior to PIBD surgery. Two patients repeatedly responded to NBD and presented with complete pruritus resolution after subsequent PIBD. NBD failed technically in the third patient, and PIBD was partially successful. Mild post-endoscopic biological pancreatitis occurred in 2/6 NBD procedures and resolved spontaneously. The only adverse effect observed within 7 years post-PIBD was very mild transient osmotic diarrhea.Conclusion: Our limited data suggest that NBD is a safe and effective way to predict pruritus response before performing permanent biliary diversion surgery in PFIC patients. What is Known: • Surgical biliary diversion techniques have been developed to relieve intractable pruritus in progressive familial intrahepatic cholestasis (PFIC). • No clinical or genetic features can currently predict pruritus response to surgery. What is New: • Our data suggest that nasobiliary drainage could be a safe and effective tool to predict pruritus response to biliary diversion and avoid unnecessary surgery in PFIC patients.

Challenges in Pediatric Liver Retransplantation: A Technical Perspective.

BACKGROUND/OBJECTIVES: Liver retransplantation (reLT) is the only option for pediatric patients experiencing graft loss. Despite recent advancements in surgical techniques and perioperative management, it remains a high-risk procedure. Our aim is to describe our experience in pediatric reLT, focusing on the technical aspects and surgical challenges. METHODS: We systematically analyzed surgical reports from pediatric reLT performed at our center between 2006 and 2023 to identify recurrent intraoperative findings and specific surgical techniques. We focused on challenges encountered during different phases of reLT, including hepatectomy, vascular, and biliary reconstruction. Additionally, we compared patient and graft survival rates among different groups. RESULTS: During the study period, 23 children underwent 25 reLT procedures at our center. Major surgical challenges included complex hepatectomy and vascular reconstructions, necessitating tailored approaches. Our analysis shows that patient and graft survival were significantly lower for reLT compared to primary transplantation (p = 0.002). Early reLT had a significantly lower graft survival compared to late reLT (p = 0.002), although patient survival was comparable (p = 0.278). Patient and graft survival rates were comparable between the first and second reLT (p = 0.300, p = 0.597). Patient survival tended to be higher after living-donor liver transplantation (LDLT) compared to deceased-donor liver transplantation (DDLT), although the difference was not statistically significant (p = 0.511). CONCLUSIONS: Pediatric reLT involves significant technical challenges and lower survival rates. Advances in perioperative management are crucial for improving outcomes. Further research is needed to optimize surgical strategies and evaluate the long-term benefits of LDLT in pediatric reLT.

Premature senescence of the liver in Alagille patients.

INTRODUCTION: Alagille syndrome (ALGS) is an autosomal dominant disease characterized by a multisystem involvement including bile duct paucity and cholestasis, caused by JAG1 or NOTCH2 mutations in most of the cases. Jagged1-Notch2 interactions are known to be crucial for intrahepatic biliary tract development, but the Notch signaling pathway is also involved in the juxtacrine transmission of senescence and in the induction and modulation of the senescence-associated secretory phenotype (SASP). AIM: Our aim was to investigate premature senescence and SASP in ALGS livers. METHODS: Liver tissue from ALGS patients was prospectively obtained at the time of liver transplantation (n = 5) and compared to control livers (n = 5). RESULTS: We evidenced advanced premature senescence in the livers of five JAG1 mutated ALGS pediatric patients through increased senescence-associated beta-galactosidase activity (p<0.05), increased p16 and p21 gene expression (p<0.01), and increased p16 and γH2AX protein expression (p<0.01). Senescence was located in hepatocytes of the whole liver parenchyma as well as in remaining bile ducts. The classical SASP markers TGF-ß1, IL-6, and IL-8 were not overexpressed in the livers of our patients. CONCLUSIONS: We demonstrate for the first time that ALGS livers display important premature senescence despite Jagged1 mutation, underlying the complexity of senescence and SASP development pathways.

Senescence and senotherapies in biliary atresia and biliary cirrhosis.

BACKGROUND: Premature senescence occurs in adult hepatobiliary diseases and worsens the prognosis through deleterious liver remodeling and hepatic dysfunction. Senescence might also arises in biliary atresia (BA), the first cause of pediatric liver transplantation. Since alternatives to transplantation are needed, our aim was to investigate premature senescence in BA and to assess senotherapies in a preclinical model of biliary cirrhosis. METHODS: BA liver tissues were prospectively obtained at hepatoportoenterostomy (n=5) and liver transplantation (n=30) and compared to controls (n=10). Senescence was investigated through spatial whole transcriptome analysis, SA-ß-gal activity, p16 and p21 expression, γ-H2AX and senescence-associated secretory phenotype (SASP). Human allogenic liver-derived progenitor cells (HALPC) or dasatinib and quercetin (D+Q) were administrated to two-month-old Wistar rats after bile duct ligation (BDL). RESULTS: Advanced premature senescence was evidenced in BA livers from early stage and continued to progress until liver transplantation. Senescence and SASP were predominant in cholangiocytes, but also present in surrounding hepatocytes. HALPC but not D+Q reduced the early marker of senescence p21 in BDL rats and improved biliary injury (serum γGT and Sox9 expression) and hepatocytes mass loss (Hnf4a). CONCLUSIONS: BA livers displayed advanced cellular senescence at diagnosis that continued to progress until liver transplantation. HALPC reduced early senescence and improved liver disease in a preclinical model of BA, providing encouraging preliminary results regarding the use of senotherapies in pediatric biliary cirrhosis.

Everolimus is Safe as a Second-/Third-Line Therapy in Pediatric Autoimmune Hepatitis.

Autoimmune hepatitis (AIH) can lead to progressive fibrosis in patients refractory to conventional therapy with prednisolone and azathioprine. The use of mammalian target of rapamycin (mTOR) inhibitors has recently emerged in refractory AIH, but no data have been published about everolimus in pediatric AIH to date. Our aim was to share our experience about everolimus as a second-/third-line therapy in pediatric AIH. Methods: Pretransplant AIH patients aged 0-18 years who received everolimus therapy from 2014 to 2021 were retrospectively identified. All patients underwent regular plasma monitoring of everolimus trough levels to avoid toxicity and assess adherence. Special attention was paid to the clinical and biochemical occurrence of everolimus-related adverse events. Results: We report six difficult-to-treat AIH patients who received everolimus therapy for 8-46 months (median 28 months). No side effects were reported when everolimus plasma trough levels were in the therapeutic range. Liver transaminases improved in 5 of 6 patients at everolimus introduction and significantly decreased at the last follow-up (FU) in our cohort (P < 0.05). None of our patients achieved complete biochemical remission at the last FU and 3 of 6 admitted to have suboptimal adherence to therapy. Conclusions: Our data bring preliminary safety for the use of everolimus as a second-/third-line therapy in pediatric AIH. Although liver transaminases improved in our cohort, prospective studies are needed to determine if everolimus can induce long-term remission.

An Optimized Protocol for Histochemical Detection of Senescence-associated Beta-galactosidase Activity in Cryopreserved Liver Tissue.

Senescence-associated beta-galactosidase (SA-ß-gal) activity assay is commonly used to evaluate the increased beta-galactosidase (ß-gal) activity in senescent cells related to enhanced lysosomal activity. Although the optimal pH for ß-gal is 4.0, this enzymatic activity has been most commonly investigated at a suboptimal pH by using histochemical reaction on fresh tissue material. In the current study, we optimized a SA-ß-gal activity histochemistry protocol that can also be applied on cryopreserved hepatic tissue. This protocol was developed on livers obtained from control rats and after bile duct resection (BDR). A significant increase in ß-gal liver activity was observed in BDR rats vs controls after 2 hr of staining at physiological pH 4.0 (6.98 ± 1.19% of stained/total area vs 0.38 ± 0.22; p<0.01) and after overnight staining at pH 5.8 (24.09 ± 6.88 vs 0.12 ± 0.08; p<0.01). Although we noticed that ß-gal activity staining decreased with cryopreservation time (from 4 to 12 months of storage at -80C; p<0.05), the enhanced staining observed in BDR compared with controls remained detectable up to 12 months after cryopreservation (p<0.01). In conclusion, we provide an optimized protocol for SA-ß-gal activity histochemical detection at physiological pH 4.0 on long-term cryopreserved liver tissue.