Feasible usage of ABO incompatible grafts in living donor liver transplantation

Clinical Relevance of Isoagglutinin Rebound in Adult ABO-Incompatible Living Donor Liver Transplantation

ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) can be performed successfully. However, anti-ABO isoagglutinin rebound may cause antibody-mediated rejection (AMR) and graft loss. The risk threshold of isoagglutinin rebound is still not defined. 76 ABO-I LDLT recipients were divided into group A (n = 56) with low isoagglutinin titers (<1:256), and group B (n = 20) with high isoagglutinin titers (≥1:256), at initial assessment for liver transplantation. The last 12 patients in group B received a modified desensitization regimen by adding bortezomib to deplete plasma cells. Six (10.7%) patients in group A and 10 (50.0%) patients in group B had postoperative isoagglutinin rebound (p < 0.001). Three patients (5.54%) in group A and two patients (10%) in group B developed clinical AMR (p = 0.602). The cutoff value of postoperative isoagglutinin rebound to cause clinical AMR was ≥1:1024. Among the 12 patients in group B with bortezomib administration, isoagglutinin rebounded up to 1:128 only, and no clinical AMR occurred. In conclusion, the patients with high isoagglutinin titers had a higher rate of postoperative isoagglutinin rebound. Isoagglutinin rebound ≥1:1024 is risky for developing clinical AMR. Adding bortezomib into the desensitization regimen may mitigate isoagglutinin rebound, and avoid clinical AMR.

Can Microscopic Biliary Reconstruction Reduce Biliary Complication Rate in ABO-Incompatible Adult Living Donor Liver Transplantation?

Background

With the introduction of rituximab, ABO-incompatible (ABOi) living donor liver transplantation (LDLT) has been considered a feasible and safe procedure to overcome the shortage of organ donors. However, higher biliary complication rates remain an unresolved problem in the ABOi group. In our center, biliary anastomosis has been done with microscopic biliary reconstruction (MBR), which effectively reduced the biliary complication rate. The aim of the current study was to investigate whether the microscopic approach reduced anastomotic biliary complications in ABOi LDLT.

Material/Methods

From March 2006 to December 2018, 30 adult ABOi and 60 ABO-compatible (ABOc) LDLT patients were selected from over 1300 recipients through 1: 2 propensity score-matched cohorts. All patients received MBR during the transplantation. Biliary complications included bile leakage and biliary stricture. Patients with diffuse intrahepatic biliary stricture were excluded from analysis.

Results

Patient characteristics were similar in the 2 groups. There was no in-hospital mortality in the ABOi LDLT. The long-term survival rates of the ABOi patients were comparable to those of the patients that underwent ABOc LDLT (87.1% vs 87.4%, P=0.964). Those in the ABOi group with anastomotic biliary complications were about 40%, which was higher than in the ABOc patients (40% vs 15%, P=0.01).

Conclusions

Microscopic biliary reconstruction does not help to reduce the high biliary complication rate in ABOi LDLT. Further investigation and identification regarding other risk factors and precautionary measures involving immunologic and adaptation mechanisms are needed.

Expanding Indications for Liver Transplant: Tumor and Patient Factors

During the past few decades, liver transplant has developed from a high-mortality procedure to an almost routine procedure with good survival outcomes. The development of living donor liver transplant has increased the availability of liver grafts, and the scope of indications for liver transplant has been expanding ever since. The aim of this review is to provide an overview of such an expansion of scope. Various criteria have been proposed to expand the eligibility of patients with hepatocellular carcinoma exceeding the Milan criteria for liver transplant. Furthermore, liver transplant is increasingly performed as a treatment modality for cholangiocarcinoma, neuroendocrine liver metastasis and colorectal liver metastasis. The number of elderly patients receiving liver transplant is on the rise. Combined organ transplantation has also been adopted to treat patients with multiple organ failure. Going forward, further development of preoperative noninvasive predictors in tumor, patient and even donor factors is needed to identify patients at risk of poor outcomes and hence optimize patient management.

No diffuse intrahepatic biliary stricture after ABO-incompatible adult living donor liver transplantation using tailored rituximab-based desensitization protocol

Background

Rituximab (RTx) desensitization protocol offered good outcome in ABO-incompatible (ABOi) living donor liver transplantation (LDLT). However, diffuse intrahepatic biliary stricture (DIHBS) is still inevitable hurdle. We selectively added postoperative high dose intravenous immunoglobulin (IVIG) and/or simultaneous splenectomy if ABO isoagglutinin titer just before liver transplantation after plasma exchange (PE) was higher than 1/16. Herein, we reported the excellent outcome of ABOi LDLT without DIHBS using tailored desensitization protocol and compared it with that of ABO-compatible (ABOc) LDLT.

Methods

Sixty-five cases (14.8%) of ABOi LDLTs were performed among 438 primary adult LDLTs in our center between March 2012 and June 2017. We performed 1-to-2 propensity score matching (PSM) to extract 60 cases of ABOi LDLTs and 120 cases of ABOc LDLTs.

Results

There were no significant differences in clinical characteristics between ABOi and ABOc recipients. There were no significant differences in complications and rejection. There was no DIHBS in both groups. The 1-, 3-, and 5-year overall survival rates were 98.3%, 86.7%, and 82.9% in ABOi group and 96.7%, 86.7%, and 85.4% in ABOc group, respectively (P=0.88). Most common cause of deaths of both groups was hepatocellular recurrence. The 1-, 3-, and 5-year biliary complication (anastomosis leakage or stricture) free survival rates were 81.4%, 69.5%, and 67.5% in ABOi group and 83.0%, 81.3%, and 80.0% in ABOc group, with no significant differences (P=0.11).

Conclusions

RTx-based tailored (optional IVIG + splenectomy) desensitization protocol for ABOi LDLT was feasible and acceptable.

Post-transplant inflow modulation for early allograft dysfunction after living donor liver transplantation

Background

To treat small-for-size syndrome (SFSS) after living donor liver transplantation (LDLT), many procedures were described for portal flow modulation before, during, or after transplantation. The selection of the procedure as well as the best timing remains controversial.

Case presentation

A 43-year-old female with end-stage liver disease underwent LDLT with extended left with caudate lobe graft from her donor who was her 41-year-old brother (graft volume/standard liver volume (GV/SLV), 35.7%; graft to recipient weight ratio (GRWR), 0.67%). During the surgery, splenectomy could not be performed owing to severe peri-splenic adhesions to avoid the ruined bleedings. The splenic artery ligation was not also completely done because it was dorsal to the pancreas and difficult to be approached. Finally, adequate portal vein (PV) inflow was confirmed after portal venous thrombectomy. As having post-transplant optional procedures that are accessible for PV flow modulation, any other procedures for PV modulation during LDLT were not done until the postoperative assessment of the graft function and PV flow for possible postoperative modulation of the portal flow accordingly. Postoperative PV flow kept as high as 30 cm/s. By the end of the 1st week, there was a progressive deterioration of the total bilirubin profile (peak as 19.4 mg/dL) and ascitic fluid amount exceeded 1000 mL/day. Therefore, splenic artery embolization was done effectively and safely on the 10th postoperative day (POD) to reverse early allograft dysfunction as PV flow significantly decreased to keep within 20 cm/s and serum total bilirubin levels gradually declined with decreased amounts of ascites below 500 mL on POD 11 and thereafter. The patient was discharged on POD 28 with good condition.

Conclusions

SFSS can be prevented or reversed by the portal inflow modulation, even by post-transplant procedure. This case emphasizes that keeping accessible angiographic treatment options for PV modulation, such as splenic artery embolization, after LDLT is quite feasible.

ABO-Incompatible Adult Living Donor Liver Transplantation in the Era of Rituximab: A Systematic Review and Meta-Analysis

Aim

The primary aim of this study is to compare the short- and long-term outcomes between ABO-incompatible (ABOi) adult living donor liver transplantation (ALDLT) with rituximab prophylaxis and ABO-compatible (ABOc) ALDLT.

Background

The strategy of ABOi liver transplantation (LT) was originated initially to increase the donor pool and to enable liver transplantation in emergency conditions. However, ABOi ALDLT remains a controversial approach in comparison to ABOc ALDLT.

Methods

PubMed, Embase, and the Cochrane Library study search were accomplished to recognize studies comparing ABOi and ABOc ALDLT. Meta-analyses were conducted based on the evaluation of heterogeneity using a fixed-effect model and a random-effect model to assess the short- and long-term outcomes following ABOi ALDLT with rituximab prophylaxis.

Results

Nine studies comprising a total of 3,922 patients (ABOi = 671 and ABOc = 3,251) were identified. There was no significant difference between ABOi and ABOc groups for 1-year, 3-year, and 5-year OS and graft survival, respectively. Moreover, 1-year and 3-year OS and DFS were similar between both groups for HCC patients. However, ABOi ALDLT had higher incidences of CMV infection, AMR, overall biliary complications, and biliary stricture than ABOc ALDLT and had other comparable postoperative complications.

Conclusion

Our meta-analysis included studies comparing ABOi and ABOc ALDLT after the introduction of rituximab in a desensitization protocol for ABOi ALDLT. The results of ABOi ALDLT were comparable with those of ABOc ALDLT. However, biliary complications, CMV infection, and AMR remain a concern in the era of rituximab.

Lessons learnt from living donor liver transplantation with ABO-incompatibility: A single-centre experience from southern India

BACKGROUND

Although, ABO-incompatible (ABOi) liver transplantation is considered a high-risk procedure, using newer and more effective preoperative B cell desensitisation techniques, many transplant centres are routinely performing ABOi living donor liver transplantation (LDLT).

METHODS

This was a retrospective study of 12 patients (adult:pediatric = 10:2; M:F = 9:3; median age, 45.5 years [range 1 to 56 years]) who underwent ABOi LDLT at a tertiary care centre.

RESULTS

The median model for end-stage liver disease (MELD)/pediatric end-stage liver disease (PELD) scores were 28 (range 18 to 35) and 30.5 (range 24 to 37), respectively. For desensitisation, we initially used two doses of rituximab and two sessions of plasmapheresis preoperatively. We faced high mortality in the initial seven patients (five deaths) due to overwhelming sepsis from multidrug-resistant (MDR) pathogens. Subsequently, we restricted the rituximab to one dose and performed plasmapheresis only when isoagglutinin titre value was more than 1:64. With this regimen, out of the last five patients, four did well. For the whole cohort, the incidence of antibody-mediated rejection, acute cellular rejection, biliary complications, hepatic artery thrombosis, infection, and 5-year patient survival were 16.7%, 16.7%, 16.7%, 8.3%, 75%, and 40%, respectively. The risk factors for mortality were high MELD score, O blood group, and more intense desensitisation protocol.

CONCLUSIONS

Careful selection of patients and less intense desensitisation protocol are probably important in improving the outcomes in ABOi LDLT.

Feasibility of using marginal liver grafts in living donor liver transplantation

Liver transplantation (LT) is one of the most effective treatments for end-stage liver disease caused by related risk factors when liver resection is contraindicated. Additionally, despite the decrease in the prevalence of hepatitis B virus (HBV) over the past two decades, the absolute number of HBsAg-positive people has increased, leading to an increase in HBV-related liver cirrhosis and hepatocellular carcinoma. Consequently, a large demand exists for LT. While the wait time for patients on the donor list is, to some degree, shorter due to the development of living donor liver transplantation (LDLT), there is still a shortage of liver grafts. Furthermore, recipients often suffer from emergent conditions, such as liver dysfunction or even hepatic encephalopathy, which can lead to a limited choice in grafts. To expand the pool of available liver grafts, one option is the use of organs that were previously considered “unusable” by many, which are often labeled “marginal” organs. Many previous studies have reported on the possibilities of using marginal grafts in orthotopic LT; however, there is still a lack of discussion on this topic, especially regarding the feasibility of using marginal grafts in LDLT. Therefore, the present review aimed to summarize the feasibility of using marginal liver grafts for LDLT and discuss the possibility of expanding the application of these grafts.

Computed tomography findings in ABO-incompatible living donor liver transplantation recipients with biliary strictures

OBJECTIVES

To evaluate CT findings of biliary strictures in ABO-incompatible living donor liver transplantation (LDLT) recipients, with emphasis on associated 1-month post-transplantation CT findings, and evaluate clinical outcomes.

METHODS

Of 351 ABO-incompatible recipients, we retrospectively evaluated CT scans in 65 recipients with biliary stricture. The biliary strictures on CT scans were classified as type A (perihilar) and type B (diffuse). Precedent CT abnormality patterns and the presence of a periportal halo sign at 1-month post-transplantation were evaluated. For each patient, clinical outcomes were evaluated.

RESULTS

Of 65 ABO-incompatible recipients with biliary strictures, 36.9% had type B strictures. Compared with biliary strictures at diagnosis, similar CT abnormality patterns were observed for 84.4% in type A and 86.4% in type B strictures at 1-month post-transplantation. Complex periportal halo signs on the 1-month post-transplantation CT were more frequently noted for type B than type A strictures (86.4% vs. 3.1%, P < 0.001). Progressive clinical outcomes were more frequently observed for type B than type A strictures (79.2% vs. 26.8%, P < 0.001), with a significantly shorter graft survival time (46.4 months vs. 90.8 months, P < 0.001).

CONCLUSION

CT abnormality patterns and complex periportal halo signs on 1-month post-transplantation CT may be clinically useful for managing biliary strictures in ABO-incompatible LDLT recipients. Key Points • Of ABO-incompatible LDLT recipients, type B biliary stricture incidence was 6.8%. • Of type B strictures, 86.4% exhibited similar CT abnormality patterns at 1-month post-transplantation. • Complex periportal halo at 1 month was significantly associated with type B strictures. • Progressive clinical outcomes were more frequently observed in type B strictures.

Outcomes after liver transplantation in accordance with ABO compatibility: A systematic review and meta-analysis

AIM

To evaluate the differences in outcomes between ABO-incompatible (ABO-I) liver transplantation (LT) and ABO-compatible (ABO-C) LT.

METHODS

A systematic review and meta-analysis were performed by searching eligible articles published before No-vember 28, 2016 on MEDLINE (PubMed), EMBASE, and Cochrane databases. The primary endpoints were graft survival, patient survival, and ABO-I-related complications.

RESULTS

Twenty-one retrospective observational studies with a total of 8247 patients were included in this meta-analysis. Pooled results of patient survival for ABO-I LT were comparable to those for ABO-C LT. However, ABO-I LT showed a poorer graft survival than ABO-C LT (1-year: OR = 0.66, 95%CI: 0.57-0.76, P < 0.001; 3-year: OR = 0.74, 95% CI 0.64-0.85, P < 0.001; 5-yearr: OR =0.75, 95%CI: 0.66-0.86, P < 0.001). Furthermore, ABO-I LT was associated with more incidences of antibody-mediated rejection (OR = 74.21, 95%CI: 16.32- 337.45, P < 0.001), chronic rejection (OR =2.28, 95%CI: 1.00-5.22, P = 0.05), cytomegalovirus infection (OR = 2.64, 95%CI: 1.63-4.29, P < 0.001), overall biliary complication (OR = 1.52, 95%CI: 1.01-2.28, P = 0.04), and hepatic artery complication (OR = 4.17, 95%CI: 2.26-7.67, P < 0.001) than ABO-C LT. In subgroup analyses, ABO-I LT and ABO-C LT showed a comparable graft survival in pediatric patients and those using rituximab, and ABO-I LT showed an increased acute cellular rejection in cases involving deceased donor grafts.

CONCLUSION

Although patient survival in ABO-I LT was comparable to that in ABO-C LT, ABO-I LT was inferior to ABO-C LT in graft survival and several complications. Graft survival of ABO-I LT could be comparable to that of ABO-C LT in pediatric patients and those using rituximab.

Simultaneous ABO-incompatible living-donor liver transplantation and splenectomy without plasma exchange in China: Two case reports

ABO-incompatible (ABO-i) living-donor liver transplantation (LDLT) is performed if an ABO-compatible graft cannot be obtained. However, a perfect desensitization protocol has not been established worldwide, especially for simultaneous ABO-i LDLT and splenectomy. We herein report two cases of ABO-i LDLT. To the best of our knowledge, this is the first case report of ABO-i LDLT in an adult patient in China. Splenectomy and T-cell-targeted immunosuppression (basiliximab) was used to overcome the blood group barrier in these recipients. The patients had good graft function without signs of antibody-mediated rejection throughout the 12-month follow-up. Thus, ABO-i LDLT with splenectomy is undoubtedly life-saving when an ABO-compatible graft cannot be obtained for patients in critical condition.