Posttransplant muscle mass measured by urinary creatinine excretion rate predicts long‐term outcomes after liver transplantation

Long‐term survival in orthotopic liver transplant (OLT) recipients remains impaired because of many contributing factors, including a low pretransplant muscle mass (or sarcopenia). However, influence of posttransplant muscle mass on survival is currently unknown. We hypothesized that posttransplant urinary creatinine excretion rate (CER), an established noninvasive marker of total body muscle mass, is associated with long‐term survival after OLT. In a single‐center cohort study of 382 adult OLT recipients, mean ± standard deviation CER at 1 year posttransplantation was 13.3 ± 3.7 mmol/24 h in men and 9.4 ± 2.6 mmol/24 h in women. During median follow‐up for 9.8 y (interquartile range 6.4‐15.0 y), 104 (27.2%) OLT recipients died and 44 (11.5%) developed graft failure. In Cox regression analyses, as continuous variable, low CER was associated with increased risk for mortality (HR = 0.43, 95% CI: 0.26‐0.71, P = .001) and graft failure (HR = 0.42, 95% CI: 0.20‐0.90, P = .03), independent of age, sex, and body surface area. Similarly, OLT recipients in the lowest tertile had an increased risk for mortality (HR = 2.69; 95% CI: 1.47‐4.91, P = .001) and graft failure (HR = 2.77, 95% CI: 1.04‐7.39, P = .04), compared to OLT recipients in the highest tertile. We conclude that 1 year posttransplant low total body muscle mass is associated with long‐term risk of mortality and graft failure in OLT recipients.     

Living vs. deceased donor liver transplantation for hepatocellular carcinoma: a systematic review and meta‐analysis

Experimental studies suggest that the regenerating liver provides a “fertile field” for the growth of hepatocellular carcinoma (HCC). However, clinical studies report conflicting results comparing living donor liver transplantation (LDLT) and deceased donor liver transplantation (DDLT) for HCC. Thus, disease‐free survival (DFS) and overall survival (OS) were compared after LDLT and DDLT for HCC in a systematic review and meta‐analysis. Twelve studies satisfied eligibility criteria for DFS, including 633 LDLT and 1232 DDLT. Twelve studies satisfied eligibility criteria for OS, including 637 LDLT and 1050 DDLT. Altogether, there were 16 unique studies; 1, 2, and 13 of these were rated as high, medium, and low quality, respectively. Studies were heterogeneous, non‐randomized, and mostly retrospective. The combined hazard ratio was 1.59 (95% confidence interval [CI]: 1.02–2.49; I² = 50.07%) for DFS after LDLT vs. DDLT for HCC, and 0.97 (95% CI: 0.73–1.27; I² = 5.68%) for OS. This analysis provides evidence of lower DFS after LDLT compared with DDLT for HCC. Improved study design and reporting is required in future research to ascribe the observed difference in DFS to study bias or biological risk specifically associated with LDLT.     

Graft‐versus‐host disease of the central nervous system after liver transplantation: A rare complication

Graft‐versus‐host disease (GVHD) of the central nervous system (CNS) following solid organ transplantation is a rare but serious complication and has been previously reported after bone marrow transplantation. GVHD after liver transplantation is a rare entity with a high mortality rate. We report the case of a patient who developed GVHD and subsequently had seizures and altered mental status after deceased donor liver transplantation. The diagnosis of GVHD of the CNS was established by short tandem repeat loci analysis of the cerebrospinal fluid using the polymerase chain reaction technique and gene mapping software. To our knowledge, this is the first reported case of CNS‐GVHD following liver transplantation. He eventually died of sepsis and multiorgan failure, in keeping with the overall poor prognosis of CNS‐GVHD.     

Reversal of secondary protein‐losing enteropathy after surgical revision of a jejunal Roux‐en‐Y loop in a patient after liver transplantation

Secondary protein‐losing enteropathy (PLE) is a rare complication following pediatric liver transplantation (LT), mostly related to venous outflow obstruction of the liver. Here, we discuss a thus far unknown cause of secondary PLE following pediatric LT. A 7‐month‐old boy underwent LT with biliary anastomosis using a Roux‐en‐Y jejunal loop. Eleven months later he developed PLE. Routine diagnostic workup was negative. No hepatic outflow obstruction was detected during catheterization. Although the hepatic venous pressure gradient was slightly increased (10 mm Hg), there were no clinical signs of portal hypertension. Albumin scintigraphy with specific early recordings suggested focal albumin intestinal entry in the jejunal Roux‐en‐Y loop. Local bacterial overgrowth or local lymphangiectasia, possibly due to (venous) congestion, was considered. Treatment with metronidazole did not improve albumin loss. Next, surgical revision of the jejunal Roux‐en‐Y loop was performed. The explanted loop contained a small abnormal area with a thin hyperemic mucosa, near the former anastomosis. Histopathological analysis showed changes both in the blood vessels and the lymphatic vessels with focal deeper chronic active inflammation resulting in congestion of vessels, hampering lymphatic outflow leading to lymphangiectasia and patchy distortion of lymphatic vessels. Following surgical revision, secondary PLE disappeared, up to now, 1.5 year post revision.     

Subclinical biliary strictures as a cause of long-term allograft dysfunction in children who underwent liver transplantation

We aimed to evaluate the role of liver biopsy to predict subclinical biliary strictures (BS) and assess the impact of BS on long-term allograft dysfunction following liver transplantation in children (LT). We reviewed all liver biopsies performed from 2012-2018. Percutaneous transhepatic cholangiography (PTC) was performed in patients presenting cholangiolar proliferation on cytokeratin-7 stained sections. We performed 271 biopsies in 161 children (86% with a left lateral segment); 44/161 (27%) presented with diffuse or multifocal cholangiolar proliferation. Among them, a tight BS was confirmed in 38/44 (86%, 24% of total) and it was managed by balloon dilatation. Cholangiolar proliferation showed a positive predictive value (PPV) for BS of 86.4%. Levels of alkaline phosphatase >325 IU/L predicted BS (P = .007). Dilatation of intrahepatic bile ducts on ultrasound was found only in 44% of patients with BS. Following a median follow-up of 9.2 years, only 15/38 (39%) patients resolved the BS. In conclusion subclinical BS is very common and probably underdiagnosed in these patients. Histological evidence of cholangiolar proliferation detectable by cytokeratin-7 immunostain should be preferred to liver function tests and ultrasound to suspect BS. BS in this setting should be regarded as a main cause of long-term allograft dysfunction.     

Impact of graft thickness reduction of left lateral segment on outcomes following pediatric living donor liver transplantation

Reducing graft thickness is essential to prevent large‐for‐size graft problems in pediatric living donor liver transplantation (LDLT). However, long‐term outcomes of LDLT using reduced‐thickness left lateral segment (LLS) grafts are unclear. In 89 patients who underwent LDLT using reduced LLS grafts between 2005 and 2017, short‐term and long‐term outcomes were compared between a nonanatomically reduced LLS (NAR‐LLS) graft group and a reduced‐thickness LLS graft group. Estimated blood loss was lower and abdominal skin closure was less needed in the recipient operation in the reduced‐thickness LLS graft group. Postoperatively, portal vein (PV) flow was significantly decreased in the NAR‐LLS graft group, and there was shorter intensive care unit (ICU) stay and fewer postoperative complications, especially bacteremia, in the reduced‐thickness LLS graft group. Graft survival at 1 and 3 years after LDLT using reduced‐thickness LLS grafts was 95.2% and 92.4%, respectively, which was significantly better than for NAR‐LLS grafts. Multivariate analysis revealed that fulminant liver failure, hepatofugal PV flow before LDLT, and NAR‐LLS graft were associated with poor graft survival. In conclusion, LDLT using reduced‐thickness LLS grafts is a safe and feasible option with better short‐ and long‐term outcomes in comparison with NAR‐LLS grafts.     

Pure laparoscopic living donor liver transplantation: Dreams come true

Minimally invasive approaches are increasingly being applied in surgeries and have recently been used in living donor hepatectomy. We have developed a safe and reproducible method for minimally invasive living donor liver transplantation, which consists of pure laparoscopic explant hepatectomy and pure laparoscopic implantation of the graft, which was inserted through a suprapubic incision. Pure laparoscopic explant hepatectomy without liver fragmentation was performed in a 60-year-old man with alcoholic liver cirrhosis and hepatocellular carcinoma. The explanted liver was retrieved through a suprapubic incision. A modified right liver graft, procured from his 24-year-old son using the pure laparoscopic method, was inserted through a suprapubic incision, and implantation was performed intracorporeally throughout the procedure. The time required to remove the liver was 369 min, and the total operative time was 960 min. No complications occurred during or after the surgery. The patient recovered well, and his hospital stay was of 11 days. Pure laparoscopic living donor liver transplantation from explant hepatectomy to implantation was performed successfully. It is a feasible procedure when performed by a highly experienced surgeon and transplantation team. Further studies with larger sample sizes are needed to confirm its safety and feasibility.

     

Sex‐based disparities in delisting for being “too sick” for liver transplantation

Women with cirrhosis awaiting liver transplantation (LT) experience higher rates of waitlist mortality than men; it is unknown whether practices surrounding delisting for being “too sick” for LT contribute to this disparity beyond death alone. We conducted an analysis of patients listed for LT in the United Network for Organ Sharing/Organ Procurement and Transplantation Network not receiving exception points from May 1, 2007 to July 1, 2014 with a primary outcome of delisting with removal codes of “too sick” or “medically unsuitable.” A total of 44 388 patients were included; 4458 were delisted for being “too sick” for LT. Delisting was more frequent in women (11% vs 9%, P < .001). Compared to delisted men, delisted women differed in age (58 vs 57), non–hepatitis C virus listing diagnoses (69% vs 56%), hepatic encephalopathy (36% vs 31%), height (161.9 vs 177.0 cm), private insurance (47% vs 52%), and Karnofsky performance status (60 vs 70) (P < .001 for all). There were no differences in Model for End‐Stage Liver Disease including serum sodium and Child Pugh Scores. A competing risk analysis demonstrated that female sex was independently associated with a 10% (confidence interval 2%‐18%) higher risk of delisting when accounting for rates of death and transplantation and adjusting for confounders. This study demonstrates a significant disparity in delisting practices by sex, highlighting the need for better assessments of sickness, particularly in women.     

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

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

Heterotopic segmental liver transplantation on splenic vessels after splenectomy with delayed native hepatectomy after graft regeneration: A new technique to enhance liver transplantation

We describe a patient with liver metastases from colorectal cancer treated with chemotherapy and hepatic resection, who developed unresectable multifocal liver recurrence and who received liver transplantation using a novel planned technique: heterotopic transplantation of segment 2-3 in the splenic fossa with splenectomy and delayed hepatectomy after regeneration of the transplanted graft. We transplanted a segmental liver graft after in-situ splitting without any impact on the waiting list, as it was previously rejected for pediatric and adult transplantation. The volume of the graft was insufficient to provide liver function to the recipient, so we performed this novel operation. The graft was anastomosed to the splenic vessels after splenectomy, and the native liver portal flow was modulated to enhance graft regeneration, leaving the native recipient liver intact. The volume of the graft doubled during the next 2 weeks and the native liver was removed. After 8 months, the patient lives with a functioning liver in the splenic fossa and without abdominal tumor recurrence. This is the first case reported of a segmental graft transplanted replacing the spleen and modulating the portal flow to favor graft growth, with delayed native hepatectomy.     

Dual‐graft adult living donor liver transplantation with ABO‐incompatible graft: short‐term and long‐term outcomes

ABO‐incompatible (ABOi) dual‐graft (DG) adult living donor liver transplantation (ALDLT) is not commonly performed due to its inherently intricate surgical technique and immunological complexity. Therefore, data are lacking on the short‐ and long‐term clinical outcomes of ABOi DG ALDLT. We performed a retrospective study by reviewing the medical records of patients who underwent ABOi DG ALDLT between 2008 and 2014. Additionally, computed tomography volumetric analysis was conducted to assess the graft regeneration rate. The mean age of a total of 28 recipients was 50.2 ± 8.5 years, and the mean model for end‐stage liver disease score was 12.2 ± 4.6. The 1‐, 3‐, and 5‐year patient survival rate was 96.4% during the mean follow‐up period of 57.0 ± 22.4 months. The 1‐, 3‐, and 5‐year graft survival rate was 96.4%, 94.2%, and 92.0%, respectively, and no significant differences were observed between ABO‐compatible (ABOc) and ABOi grafts (P = .145). The biliary complication rate showed no significant difference (P = .195) between ABOc and ABOi grafts. Regeneration rates of ABOi grafts were not significantly different from those of ABOc grafts. DG ALDLT with ABOi and ABOc graft combination seems to be a feasible option for expanding the donor pool without additional donor risks.     

Meta-analysis and meta-regression of outcomes for adult living donor liver transplantation versus deceased donor liver transplantation

Prior single center or registry studies have shown that living donor liver transplantation (LDLT) decreases waitlist mortality and offers superior patient survival over deceased donor liver transplantation (DDLT). The aim of this study was to compare outcomes for adult LDLT and DDLT via systematic review. A meta-analysis was conducted to examine patient survival and graft survival, MELD, waiting time, technical complications, and postoperative infections. Out of 8600 abstracts, 19 international studies comparing adult LDLT and DDLT published between 1/2005 and 12/2017 were included. U.S. outcomes were analyzed using registry data. Overall, 4571 LDLT and 66,826 DDLT patients were examined. LDLT was associated with lower mortality at 1, 3, and 5 years posttransplant (5-year HR 0.87 [95% CI 0.81–0.93], p < .0001), similar graft survival, lower MELD at transplant (p < .04), shorter waiting time (p < .0001), and lower risk of rejection (p = .02), with a higher risk of biliary complications (OR 2.14, p < .0001). No differences were observed in rates of hepatic artery thrombosis. In meta-regression analysis, MELD difference was significantly associated with posttransplant survival (R² 0.56, p = .02). In conclusion, LDLT is associated with improved patient survival, less waiting time, and lower MELD at LT, despite posing a higher risk of biliary complications that did not affect survival posttransplant.     

Living‐donor liver transplantation for liver hemorrhaging due to peliosis hepatis in X‐linked myotubular myopathy: Two cases and a literature review

X‐linked myotubular myopathy (MTM) (OMIM 310400) is a severe neuromuscular disorder caused by mutations in the myotubularin (MTM1) gene. Liver hemorrhaging due to peliosis hepatis (PH) is a fatal complication. We herein report 2 successful cases of living‐donor liver transplantation (LDLT) for MTM patients due to liver hemorrhaging caused by PH and review previous reports. A boy who was 9 years and 4 months old initially underwent left lateral segmentectomy due to massive hepatic and intraperitoneal hemorrhaging. As bleeding from the remnant liver continued after hepatectomy, this patient emergently underwent LDLT using a left lateral segment graft from his father. Another boy who was 1 year and 7 months old underwent transcatheter arterial embolization due to hepatic hemorrhaging and was referred to our hospital for LDLT using a left lateral segment graft from his father. The pathological findings in both cases showed sinusoidal dilatation with degenerative changes in reticular fiber and hematoma in the explanted liver, which were consistent with PH associated with MTM. LT should be considered as a treatment option for patients with episodes of hepatic hemorrhaging due to MTM in order to protect against fatal bleeding.     

Cytomegalovirus (CMV) infection and risk of mortality in allogeneic hematopoietic stem cell transplantation (Allo‐HSCT): A systematic review,meta‐analysis,and meta‐regression analysis

Controversy surrounds the potential association between cytomegalovirus (CMV) infection and increased risk of mortality after allogeneic hematopoietic stem cell transplantation (Allo‐HSCT). A systematic literature search was conducted using the PubMed, EMBASE, and Web of Science databases, assessing the association between CMV infection, as documented by the pp65 antigenemia assay or by polymerase chain reaction (PCR) using blood specimens, and overall mortality (OM) and nonrelapse mortality (NRM) in the allo‐HSCT setting. Pooled effects were estimated using the generic inverse variance random effects model. Heterogeneity was evaluated by Cochrane's Q test and I² statistics. The source of heterogeneity was investigated by meta‐regression and subgroup analyses. Twenty‐six of 1367 studies fulfilled eligibility criteria. CMV infection identified by PCR monitoring was significantly associated with an increased risk of OM and NRM (hazard ratio 1.47, 95% confidence interval [1.20‐1.81], P ≤ .001; hazard ratio 1.68, 95% confidence interval [1.14‐2.49], P = .05, respectively). In this setting, the use of preemptive antiviral therapy (PET) resulted in a twofold increased risk of OM and NRM. The estimated effect sizes were associated with allo‐HSCT modalities. Although our analyses point to an association between CMV infection and an increased risk of OM and NRM in allo‐HSCT recipients, the high heterogeneity across studies prevented drawing of robust conclusions on this matter.     

Effect of CYP3A5*1 expression on tacrolimus required dose after liver transplantation: A systematic review and meta‐analysis

We systematically collected eligible data to measure the effect of CYP3A5*1 expression on personalized tacrolimus therapy. Six databases were searched for studies on adult liver transplant recipients and donors of liver graft which reported tacrolimus dose requirement, trough blood concentration, and/or concentration/dose (C/D) ratio in expressers and nonexpressers of CYP3A5*1. Eligible data were pooled by meta‐analysis. Sixteen observational studies (1309 recipients, 1044 donors of liver graft) were included in the analyses. Tacrolimus C/D ratio was lower, and the dose was higher in recipient expressers of CYP3A5*1 and/or carriers of expresser liver graft at 1‐4 weeks and 2‐4, 6, and 12 months post‐transplantation. Tacrolimus blood concentration was lower at the first two weeks. Pair expressers were affected by about twofold, and the effect was different between ethnic groups. CYP3A5*1 expression in recipients increased tacrolimus required dose by 0.023 at first, 0.022 at third, and 0.012 mg/kg/day at sixth month. Its expression in graft tissue increased tacrolimus required dose by 0.024 at first, 0.035 at third, and 0.032 mg/kg/day at sixth month. Considering CYP3A5*1 polymorphism can be helpful in individualization of tacrolimus efficient dose prior to administration, and it can remove initial high‐risk lag time (over/underdose period before reaching target blood level) at first few days post‐transplantation.     

Pediatric living donor liver transplantation with large‐for‐size left lateral segment grafts

Usage of “large‐for‐size” left lateral segment (LLS) liver grafts in children with high graft to recipient weight ratio (GRWR) is controversial due to concerns about increased recipient complications. During the study period, 77 pediatric living donor liver transplantations (LDLTs) with LLS grafts were performed. We compared recipients with GRWR ≥2.5% (GR‐High = 50) vs GRWR <2.5% (GR‐Low = 27). Median age was higher in the GR‐Low group (40 vs 8 months, P> .0001). Graft (GR‐High: 98%, 98%, 98% vs GR‐Low: 96%, 93%, 93%) and patient (GR‐High: 98%, 98%, 98% vs GR‐Low: 100%, 96%, 96%) survival at 1, 3, and 5 years was similar between groups (P = NS). Overall complications were also similar (34% vs 30%; P = .8). Hepatic artery and portal vein thrombosis following transplantation was not different (P = NS). Delayed abdominal fascia closure was more common in GR‐High patients (17 vs 1; P = .002). Subgroup analysis comparing recipients with GRWR ≥4% (GR‐XL = 20) to GRWR <2.5% (GRWR‐Low = 27) revealed that delayed abdominal fascia closure was more common in the GR‐XL group, but postoperative complications and graft and patient survival were similar. We conclude that pediatric LDLT with large‐for‐size LLS grafts is associated with excellent clinical outcomes. There is an increased need for delayed abdominal closure with no compromise of long‐term outcomes. The use of high GRWR expands the donor pool and improves timely access to the benefits of transplantation without extra risks.     

The first case of ischemia‐free organ transplantation in humans: A proof of concept

Ischemia and reperfusion injury (IRI) is an inevitable event in conventional organ transplant procedure and is associated with significant mortality and morbidity post‐transplantation. We hypothesize that IRI is avoidable if the blood supply for the organ is not stopped, thus resulting in optimal transplant outcomes. Here we described the first case of a novel procedure called ischemia‐free organ transplantation (IFOT) for patients with end‐stage liver disease. The liver graft with severe macrovesicular steatosis was donated from a 25‐year‐old man. The recipient was a 51‐year‐old man with decompensated liver cirrhosis and hepatocellular carcinoma. The graft was procured, preserved, and implanted under continuous normothermic machine perfusion. The recipient did not suffer post‐reperfusion syndrome or vasoplegia after revascularization of the allograft. The liver function test and histological study revealed minimal hepatocyte, biliary epithelium and vascular endothelium injury during preservation and post‐transplantation. The inflammatory cytokine levels were much lower in IFOT than those in conventional procedure. Key pathways involved in IRI were not activated after allograft revascularization. No rejection, or vascular or biliary complications occurred. The patient was discharged on day 18 post‐transplantation. This marks the first case of IFOT in humans, offering opportunities to optimize transplant outcomes and maximize donor organ utilization.