Current progress in ABO-incompatible liver transplantation

Impact of Baseline Anti-ABO Antibody Titer on Biliary Complications in ABO-Incompatible Living-Donor Liver Transplantation

Background: Although advancements in desensitization protocols have led to increased ABO-incompatible (ABOi) living-donor liver transplantation (LDLT), a higher biliary complication rate remains a problem. This study evaluated the effect of baseline anti-ABO antibody titers before desensitization on biliary complications after ABOi LDLT. Methods: The study cohort comprised 116 patients in the ABO-compatible group (ABOc), 29 in the ABOi with the low titer (<1:128) group (ABOi-L), and 14 in the high titer (≥1:128) group (ABOi-H). Results: Biliary complications occurred more frequently in the ABOi-H group than in the ABOi-L and ABOc groups (7 [50.0%] vs. 8 [27.6%] and 24 [20.7%], respectively, p = 0.041). Biliary complication-free survival was significantly worse in the ABOi-H group than in the other groups (p = 0.043). Diffuse intrahepatic biliary strictures occurred more frequently in the ABOi-H group than in the other groups (p = 0.005). Multivariable analysis revealed that the high anti-ABO antibody titer (≥1:128) is an independent risk factor for biliary complications (hazard ratio 3.943 [1.635-9.506]; p = 0.002). Conclusions: A high baseline anti-ABO antibody titer (≥1:128), female sex, and hepatic artery complications are significant risk factors for biliary complications.

Accidental ABO-incompatible pediatric liver transplantation with blood group antigen immune and operational tolerance: a case report with 21 years of follow-up

Liver transplantation is a critical procedure for patients with end-stage liver disease, but it is often hindered by ABO-incompatibility between the donor and recipient, which can lead to immediate humoral rejection. We present a unique case involving a 10-month-old patient who, by accident, received an ABO-incompatible partial liver transplant from a type A mother without undergoing desensitization. Remarkably, during a 21-year follow-up period, the patient exhibited no signs of humoral or graft rejection, despite nonadherence to medication. This case highlights the possibility of dual tolerance in pediatric ABO-incompatible liver transplantation and provides insights into immune tolerance mechanisms, with implications for enhancing patient care and reducing healthcare costs. Further research is necessary to clarify these mechanisms and to evaluate the long-term durability of tolerance in pediatric transplant recipients.

Long-term outcomes following ABO-incompatible living donor liver transplantation for acute liver failure: a single-center experience of over 20 years

PURPOSE

Acute liver failure is a life-threatening condition for which ABO-incompatible living donor liver transplantation (ABOi-LDLT) is sometimes the only life-saving treatment option. We reviewed a single-center experience of adult ABOi-LDLT treatment for acute liver failure (ALF).

METHODS

Preoperative treatment, immune indices (B cell marker, anti-donor blood-type antibody), and postoperative outcomes were compared between ALF and non-ALF groups.

RESULTS

There were 5 and 33 patients in the ALF and non-ALF groups, respectively. The ALF group received higher doses of steroids, underwent more rounds of plasma exchange (PE), and underwent transplantation for ALF with a shorter interval following preoperative rituximab (RTx) administration (median: 2 vs 13 days; P < 0.05) than the non-ALF group. Preoperatively, CD19-positive lymphocytes in the peripheral blood were sufficiently depleted in all of the non-ALF group patients, whereas they were poorly depleted in the ALF group. Postoperatively, neither group suffered anti-donor blood-type antibody titer rebound or antibody-mediated rejection. The ALF group had a comparable 5-year survival rate to the non-ALF group (80.0% vs 77.9%).

CONCLUSIONS

Despite the delayed preoperative administration of RTx, the ALF group showed an uneventful immunological response and acceptable long-term survival rate. Thus, ABOi-LDLT seems a viable treatment option for ALF.

Strategies for ABO Incompatible Liver Transplantation

Liver transplantation (LT) is a definitive treatment for the decompensated liver cirrhosis and fulminant liver failure. With limited availability of cadaveric liver allograft, ABO incompatible (ABOi) living donor liver transplantation (LDLT) plays an important part in further expansion of donor pool. Over the years, with the introduction of Rituximab and improving desensitisation protocol, outcomes of ABOi LDLT are on par with ABO compatible LT. However, ABOi LDLT protocol varies markedly from centre to centre. Intravenous Rituximab followed by plasmapheresis or immunoadsorption effectively reduce ABO isoagglutinins titre before transplant, thereby reducing the risk of antibody mediated rejection in the post-transplant period. Local infusion therapy and splenectomy are not used routinely at most of the centres in Rituximab era. Post-transplant immunosuppression usually consists of standard triple drug regime, and tacrolimus trough levels are targeted at higher level compared to ABO compatible LT. Introduction of newer therapies like Belatacept and Obinutuzumab hold promise to further improve outcomes and reduce the risk of antibody mediated rejection related complications. ABOi LT in emergency situations like acute liver failure and deceased donor LT is challenging due to limited time period for desensitisation protocol before transplant, and available evidence are still limited but encouraging.

Outcomes after ABO incompatible pediatric liver transplantation are comparable to ABO identical/compatible transplant

Background

ABO incompatible (ABOi) liver transplantation (LT) was initially associated with a higher incidence of vascular, biliary, and rejection complications and a lower survival than ABO compatible (ABOc) LT. Various protocols have been proposed to manage anti-isohemagglutinin antibodies and hyperacute rejection. We present our experience with a simplified protocol using only plasmapheresis.

Methods

A retrospective review of all patients who received an ABOi LT at our institution was performed. Comparisons were made based on era (early: 1997-2008, modern: 2009-2020) and severity of disease (status 1 vs. exception PELD at transplant). A pair-matched comparison was done to patients who received an ABOc LT. p < 0.05 was considered significant.

Results

17 patients received 18 ABOi LT (3 retransplants). Median age at transplant was 7.4 months (1.1-28.9). 66.7% patients were listed as status 1. Hepatic artery thrombosis (HAT) occurred in one patient (5.6%), there were 2 cases of portal vein thrombosis (PVT) (11.1%), and 2 biliary strictures (11.1%). Patient and graft survival improved in the ABOi modern era, although not significantly. In the pair-matched comparison, complications (HAT p = 0.29; PVT p = 0.37; biliary complications p = 0.15) and survival rates were similar. Patient and graft survivals were 100% in the non-status 1 ABOi patients compared to 67% (p = 0.11) and 58% (p = 0.081) respectively for patients who were transplanted as status 1.

Conclusion

ABO incompatible liver transplants in infants with a high PELD score have excellent outcomes. Indications for ABO incompatible transplants should be liberalized to prevent deaths on the waiting list or deterioration of children with high PELD scores.

The role of herpesviruses and pneumocysts in infectious complications in children during liver transplantation

Infections occupy one of the central places among the complications of transplants. The frequency of fatal infectious complications during the first twelve months after transplantation ranges from 2.6 to 51.7%. Identifying markers of opportunistic infections before transplantation will help reduce the likelihood of developing these infections after induced immunosuppression. The aim of the study was to study the role of herpesviruses and pneumocysts in the occurrence of infectious complications in children before and after liver transplantation based on the detection of markers of a number of herpesvirus infections and pneumocystosis. The article presents the results of a comprehensive examination for markers of herpesvirus infections and pneumocystosis of 70 children who were treated at the Shumakov Transplantation Research Center. It should be noted that 55 patients (78.6%) were diagnosed with infectious complications, of which 46 people (65.7%) had pneumonia. To detect IgM and IgG antibodies to herpesviruses and pneumocysts, peripheral blood serum samples were examined by enzyme immunoassay (ELISA). Detection of common HBV antigens was carried out by indirect immunofluorescence reaction (NRIF). Early antigens and reproduction of herpesviruses were detected by rapid culture method (BCM) on Vero and M-19 cell cultures for CMVI. In the event of infectious complications (pneumonia) in children who underwent related liver transplantation, the number of patients with active EBI markers increased almost 7 times and active HCV-6 markers increased 3.5 times. The paper shows the need for a broader laboratory screening of opportunistic infections, which will serve to achieve better clinical results, contribute to the formation of more advanced diagnostic algorithms, as well as improve epidemiological surveillance of these infections.

Decellularized Organ-Derived Scaffold Is a Promising Carrier for Human Induced Pluripotent Stem Cells-Derived Hepatocytes

Human induced pluripotent stem cells (hiPSCs) are a promising cell source for elucidating disease pathology and therapy. The mass supply of hiPSC-derived cells is technically feasible. Carriers that can contain a large number of hiPSC-derived cells and evaluate their functions in vivo-like environments will become increasingly important for understanding disease pathogenesis or treating end-stage organ failure. hiPSC-derived hepatocyte-like cells (hiPSC-HLCs; 5 × 10⁸) were seeded into decellularized organ-derived scaffolds under circumfusion culture. The scaffolds were implanted into immunodeficient microminiature pigs to examine their applicability in vivo. The seeded hiPSC-HLCs demonstrated increased albumin secretion and up-regulated cytochrome P450 activities compared with those in standard two-dimensional culture conditions. Moreover, they showed long-term survival accompanied by neovascularization in vivo. The decellularized organ-derived scaffold is a promising carrier for hiPSC-derived cells for ex vivo and in vivo use and is an essential platform for regenerative medicine and research.

Quick preparation of ABO-incompatible living donor liver transplantation for acute liver failure

Acute liver failure is life-threatening and has to be treated by liver transplantation urgently. When deceased donors or ABO-compatible living donors are not available, ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) becomes the only choice. How to prepare ABO-I LDLT urgently is an unsolved issue. A quick preparation regimen was designed, which was consisted of bortezomib (3.5mg) injection to deplete plasma cells and plasma exchange to achieve isoagglutinin titer ≤ 1: 64 just prior to liver transplantation and followed by rituximab (375mg/m² ) on post-operative day one to deplete B-cells. Eight patients received this quick preparation regimen to undergo ABO-I LDLT for acute liver failure from 2012 to 2019. They aged between 50 and 60 years. The median MELD score was 39 with a range from 35 to 48. It took 4.75 ± 1.58 days to prepare such an urgent ABO-I LDLT. All the patients had successful liver transplantations, but one patient died of antibody-mediated rejection at post-operative month 6. The 3-month, 6-month, and 1-year graft/patient survival were 100%, 87.5%, and 75%, respectively. In conclusion, this quick preparation regimen can reduce isoagglutinin titers quickly and make timely ABO-I LDLT feasible for acute liver failure. This article is protected by copyright. All rights reserved.

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.

Diagnostic Utility of Presepsin in Infections After Liver Transplantation: A Preliminary Study

BACKGROUND Infectious complications after solid organ transplantation can be fatal, and early diagnosis and intervention are important. To the best of our knowledge, no study has examined the diagnostic utility of presepsin, a known accurate biomarker, for infectious complications after liver transplantation. This study aimed to evaluate the utility of presepsin for detecting infection and perioperative kinetics of presepsin after liver transplantation. MATERIAL AND METHODS This single-institutional prospective, observational study included 13 patients who underwent living-donor or deceased-donor liver transplantation. Perioperative serum presepsin level was measured 6 times within a week to evaluate its association with infectious complications and compare it with procalcitonin and C-reactive protein levels and leukocyte count. Postoperatively, patients were followed up for 15 days for infectious complications. RESULTS Five of the 13 patients developed infectious complications after liver transplantation. The median time for infection diagnosis was 9 postoperative days (25th-75th percentile, 7-10). Presepsin levels on 5 and 7 postoperative days were significantly higher in patients with infection than in those without (P=0.019 and P=0.011, respectively). In receiver operating characteristic analysis, area under the curve values of presepsin on 5 and 7 postoperative days (0.881 and 0.905, respectively) were higher than those of other biomarkers. The optimal cut-off value of presepsin was 1361 pg/mL on postoperative day 5 and 1375 pg/mL on postoperative day 7. CONCLUSIONS Although this study included a small number of patients, presepsin levels on postoperative days 5 and 7 may be useful indicators for infectious complications after liver transplantation.

ABO Incompatible Liver Transplantation in Children: A 20 Year Experience from Centres in the TransplantChild European Reference Network

An increasing number of AB0-incompatible (AB0i) liver transplantations (LT) are being undertaken internationally in recent years due to organ shortages and the need for urgent transplantation. The aim of our study was establish the value of ABOi LT from available retrospective results of AB0i pediatric liver transplantations performed in European reference centers now belonging to the TransplantChild, European Reference Network (ERN). Data from medical records were analyzed, including demographic data, diagnosis, urgency of transplantation, time on the waiting list, PELD/MELD score, desensitization procedures, immunosuppression, selected post-transplant complications, and patient and graft survival. A total of 142 patients (pts) with transplants between 1986 and 2018 in 8 European transplant centers were included in the study. The indications for liver transplantation were: cholestatic diseases in 62 pts, acute liver failure in 42 pts, and other conditions in the remaining 38 pts. Sixty-six patients received grafts from living donors, and seventy-six received grafts from deceased donors. Both patient and graft survival were significantly affected by deceased donor type, urgent transplantation, and the development of vascular complications. In the multivariate analysis, vascular complications had a negative impact on patient and graft survival, while a longer time from the first AB0i LT in the study showed better results, suggesting an international learning experience. In conclusion, we believe that AB0i LT in children is now a safe procedure that may be adopted more readily in children.

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.

Invasive pulmonary aspergillosis after liver transplantation: lessons from successfully treated cases and review of the literature

PURPOSE

Invasive pulmonary aspergillosis (IPA) after liver transplantation (LT) is most often fatal. We analyzed the outcomes of IPA in a single center.

METHODS

We reviewed, retrospectively, the medical records of recipients of living donor LT (LDLT) or deceased donor LT (DDLT) performed between 1995 and 2019 at our institute. We analyzed the incidence of IPA and assessed the treatment courses of patients treated successfully and those not treatment successfully.

RESULTS

Among 326 recipients, IPA was diagnosed in 6 (1.8%). The incidence of IPA was significantly higher in patients with acute liver failure (ALF, 9.8%) than in those without ALF (0.4%), after DDLT (8.8%) than after LDLT (1.0%), and in recipients who received preoperative steroid pulse therapy (16.0%) than in those who did not (0.7%). Complete cure of IPA was achieved in the most recent three patients, by administering voriconazole immediately after the diagnosis of IPA and performing lung resection, while the IPA lesion was single and localized.

CONCLUSIONS

Patients with risk factors for IPA must be monitored closely. Our three successfully treated cases demonstrate that initiating immediate voriconazole treatment and making a calculated decision about lung resection can contribute to a favorable outcome.

Characteristics of Immunoglobulin M Type Antibodies of Different Origins from the Immunologic and Clinical Viewpoints and Their Application in Controlling Antibody-Mediated Allograft Rejection

Antibody-mediated allograft rejection (AMR) hinders patient prognosis after organ transplantation. Current studies concerning AMR have mainly focused on the diagnostic value of immunoglobulin G (IgG)-type donor-specific antihuman leukocyte antigen antibodies (DSAs), primarily because of their antigen specificity, whereas the clinical significance of immunoglobulin M (IgM)-type DSAs has not been thoroughly investigated in the context of organ transplantation because of their nonspecificity against antigens. Although consensus regarding the clinical significance and role of IgM antibodies is not clear, as discussed in this review, recent findings strongly suggest that they also have a huge potential in novel diagnostic as well as therapeutic application for the prevention of AMR. Most serum IgM antibodies are known to comprise natural antibodies with low affinity toward antigens, and this is derived from B-1 cells (innate B cells). However, some of the serum IgM-type antibodies reportedly also produced by B-2 cells (conventional B cells). The latter are known to have a high affinity for donor-specific antigens. In this review, we initially discuss how IgM-type antibodies of different origins participate in the pathology of various diseases, directly or through cell surface receptors, complement activation, or cytokine production. Then, we discuss the clinical applicability of B-1 and B-2 cell-derived IgM-type antibodies for controlling AMR with reference to the involvement of IgM antibodies in various pathological conditions.

Myelopathy due to human T-cell leukemia virus type-1 from the donor after ABO-incompatible liver transplantation

We report the case of a 53-year-old-man who developed human T-cell leukemia virus type-1-associated myelopathy (HAM) after ABO-incompatible liver transplantation for alcoholic liver cirrhosis. The living donor was seropositive for human T-cell leukemia virus type-1 (HTLV-1) and the recipient was seronegative for HTLV-1 before transplantation. After transplantation, the recipient developed steroid-resistant acute cellular rejection, which was successfully treated using anti-thymocyte globulin, and he was eventually discharged. He underwent spinal surgery twice after the transplantation for the treatment of cervical spondylosis that had been present for a period of 9 months before the transplantation. The surgery improved his gait impairment temporarily. However, his gait impairment progressed, and magnetic resonance imaging revealed multiple sites of myelopathy. He was diagnosed with HAM 16 months after the transplantation. Pulse steroid therapy (1000mg) was administered over a period of 3 days, and his limb paresis improved. Presently, steroid therapy is being continued, with a plan to eventually taper the dose, and he is being carefully followed up at our institution. Our case suggests that liver transplantation involving an HTLV-1-positive living donor carries the risk of virus transmission and short-term development of HAM after transplantation.

Methicillin-resistant Staphylococcus aureus carriers are vulnerable to bloodstream infection after living donor liver transplantation

BACKGROUND

Bloodstream infection (BSI) is a life-threatening complication after living donor liver transplantation (LDLT). We aimed to explore the incidence and predisposing factors of BSI at our institution.

METHODS

We conducted a retrospective cohort analysis on all consecutive adults with BSI within 6 months after LDLT performed between 2005 and 2016. For antimicrobial prophylaxis, ampicillin/sulbactam, cefotaxime, and micafungin were administered. From 2011, methicillin-resistant Staphylococcus aureus (MRSA) carriers were decolonized using mupirocin ointment and chlorhexidine gluconate soap. Risk factors for BSI were identified by uni- and multivariate logistic regression.

RESULTS

Of a total of 106 LDLTs, 42 recipients (40%) suffered BSI. The BSI group demonstrated significantly higher in-hospital mortality rates compared with the non-BSI group (24% vs. 7%, P = .01). We identified MRSA carrier (odds ratio [OR], 19.1; P < .001), ABO incompatibility (OR, 2.9; P = .03), and estimated glomerular filtration rate <30 mL/min/1.73m² (OR, 15.8; P = .02) as independent risk factors for BSI. Decolonization treatment for MRSA carriers did not reduce the incidence of all-cause BSI but reduced the frequency of BSI caused by MRSA.

CONCLUSION

To our knowledge, for the first time, MRSA carriers were revealed to be highly vulnerable to BSI after LDLT.

Preformed donor-specific antibodies are associated with 90-day mortality in living-donor liver transplantation

AIM

The impact of donor-specific anti-human leukocyte antigen (HLA) antibodies (DSAs) on living donor liver transplantation (LDLT) is unclear. The aim of this study was to investigate the association between DSAs and short-term outcomes in LDLT recipients, and to clarify the clinical impact of DSAs.

METHOD

Anti-HLA antibodies were screened in preoperative serum samples taken from 40 liver transplant recipients at Ehime University (Toon, Japan) between August 2001 and July 2015. Screening was carried out using the Flow-PRA method, and DSAs were detected in anti-HLA antibody-positive recipients using the Luminex single-antigen identification test. A mean fluorescence intensity of 1000 was used as the cut-off for positivity. We retrospectively reviewed the clinical courses of patients who were DSA-positive to elucidate early clinical manifestations in LDLT recipients.

RESULTS

Fifteen (12 female and 3 male) patients (38%) had anti-HLA antibodies. Eight of the 15 anti-HLA antibody-positive patients were positive for DSAs, and all were women. The 90-day survival rate of DSA-positive patients (50%) was significantly lower than that of DSA-negative patients (84.4%) (0.0112; Wilcoxon test). On univariate analysis, the DSA-positive rate was significantly higher in the 90-day mortality group. Postoperatively, the incidence of acute cellular rejection was higher in DSA-positive than DSA-negative patients. Thrombotic microangiopathy developed only in DSA-positive patients. We found no relationship between DSA status and bile duct stricture.

CONCLUSION

Preformed DSAs could be associated with elevated 90-day mortality in LDLT recipients. Further large-scale studies are required to verify the risk associated with DSAs in LDLT.

Immunologic strategies and outcomes in ABO-incompatible living donor liver transplantation

Antibody mediated rejection (AMR) after adult ABO-incompatible living donor liver transplantation (ABO-I LDLT) induced hepatic necrosis or diffuse intrahepatic biliary complications, which were related with poor graft and patient survival. Various desensitization protocols have been used to overcome these problems. Since using rituximab, the outcomes of ABO-I LDLT show a similar survival rate to those of ABO-compatible living donor liver transplantation. However, diffuse bile duct complications still occur after ABO-I LDLT. We have reviewed the past and current immune strategies for desensitization and to provide outcomes and ABO incompatibility-related complications in ABO-I LDLT.

A simplified protocol using rituximab and immunoglobulin for ABO-incompatible low-titre living donor liver transplantation

BACKGROUND & AIMS

No consensus has been reached regarding optimal treatment strategies for ABO-incompatible (ABO-I) living donor liver transplantation (LDLT). We introduce a simplified protocol using rituximab and intravenous immunoglobulin (IVIG).

METHODS

Data were analysed on adult patients who underwent ABO-I LDLT of which protocol added rituximab (300 mg/m² ) before surgery and IVIG (0.8 g/kg) on post-operative days 1 and 4 to the conventional immunosuppressive regimen used in ABO-compatible (ABO-C) LDLT, without plasmapheresis, splenectomy or graft local infusion. The outcomes were compared with those of ABO-C LDLT by 1:2 propensity score-matched analysis.

RESULTS

Consecutive 43 ABO-I LDLT patients were identified between 2014 and 2016. Before desensitization, the median isoagglutinin titre was 1:8 (range, 1:2-1:64). The titre was reduced to 4 (range, 0-16) at the time of LDLT. None showed a rebound rise of isoagglutinin titres. No antibody-mediated rejection occurred. Biliary stricture was the most common complication with an incidence of 30.2%. A comparator group of 86 ABO-C LDLT patients were selected. There was no statistical difference in the overall complication rate including acute cellular rejection, biliary complications and infection between ABO-I and ABO-C groups. The 3-year cumulative patient survival rates in the ABO-I and ABO-C groups were 82.4% and 85.9% respectively (P = .115).

CONCLUSIONS

A simplified protocol using rituximab and IVIG for ABO-I LDLT was safe and effective in achieving sufficient desensitization and comparable outcomes in patients with the titre no higher than 1:64.

A comparison of desensitization methods: Rituximab with/without plasmapheresis in ABO-incompatible living donor liver transplantation

BACKGROUND

Plasmapheresis is a desensitization method used prior to ABO-incompatible (ABO-I) living donor liver transplantation. However, studies on its usefulness in the rituximab era are lacking.

METHODS

Fifty-six adult patients underwent ABO-I living donor liver transplantation between January 2012 and October 2015. A single dose of rituximab (300 mg/m²) was administered 2 weeks before surgery with plasmapheresis in all patients until February 2014 (RP group, n = 26). Patients were administered rituximab only, without plasmapheresis between March 2014 and October 2015 (RO group, n = 30).

RESULTS

The 6-, 12- and 18-month overall survival rates were 92.3%, 80.8% and 76.9% in the RP group and 96.6%, 85.4% and 85.4% in the RO group, respectively (P = 0.574). When the initial isoagglutinin titers < 16, neither group showed a rebound rise of isoagglutinin titers. For patients with initial isoagglutinin titers ≥ 16, the rebound rise of isoagglutinin titers was more prominent in the RP group. There was no difference in time-dependent changes in B cell subpopulations and ABO-I-related complications.

CONCLUSIONS

Sufficient desensitization for ABO-I living donor liver transplantation can be achieved using rituximab alone. This desensitization strategy does not affect the isoagglutinin titers, ABO-I-related complications and patient survival.

Successful living donor liver retransplantation for graft failure within 7 days due to acute de novo donor-specific anti-human leukocyte antigen antibody-mediated rejection

Growing evidence suggests a relationship between antibody-mediated rejection (AMR) and early graft failure due to a previously unknown etiology in liver transplantation (LTx). We herein report a 3-year-old boy who developed rapid graft failure due to de novo donor-specific antibody (DSA)-driven AMR a week after living donor LTx, requiring a second transplant on the 10th day after the first LTx. The pathology of the first graft showed massive necrosis in zone 3 along with positive C4d and inflammatory cell infiltrates in portal areas. The mean fluorescence intensity against human leukocyte antigen (HLA)-DR15, which was possessed by both the first and the second donor, peaked at 12 945 on the day before the second LTx. Antithymocyte globulin, plasma exchange along with i.v. immunoglobulin, rituximab, and the local infusion of prostaglandin E1, steroids, and Mesilate gabexate through a portal catheter were provided to save the second graft. To our knowledge, this is the first report to show a clear association between de novo DSA and acute AMR within 7 days of a LTx. Furthermore, we successfully rescued the recipient with a second graft despite possessing the same targeted HLA. The rapid decision to carry out retransplantation and specific strategies overcoming AMR were crucial to achieving success in this case of immunologically high-risk LTx.

Tolvaptan for Fluid Management in Living Donor Liver Transplant Recipients

BACKGROUND Tolvaptan, an antagonist of the vasopressin V2 receptor is a novel oral diuretic that promotes water excretion selectively. We have used furosemide as a primary diuretic and added human atrial natriuretic peptide (hANP) if necessary for fluid management postoperatively in living-donor liver transplantation (LDLT) recipients. Recently we introduced tolvaptan and used both tolvaptan and furosemide as primary diuretics. MATERIAL AND METHODS Clinical outcomes were compared between LDLT recipients whose postoperative fluid management was performed before (control group, n=10) and after (tolvaptan group, n=16) introduction of tolvaptan. RESULTS Preoperative and intraoperative demographic data did not differ significantly between the groups except for the period of post-surgical follow-up and total ischemic time. Urine volume was 1,242±692, 2,240±1307, and 2,268±1262 mL on postoperative day 1, 3, and 7, respectively, in the tolvaptan group. These volumes did not significantly differ from those in control group (1,027±462, 1,788±909, and 2,057±1216 mL on day 1, 3, and 7 postoperatively, respectively). Body weight gain and fluid volume from abdominal drainage tubes postoperatively did not differ significantly between groups. The time from hANP initiation to discontinuation and the time to removal of central vein catheters were significantly reduced in tolvaptan-treated patients. No severe side effects directly related to tolvaptan were observed. The survival rate at month 6 was 90.0% in control patients versus 93.8% in tolvaptan-treated patients. CONCLUSIONS The outcomes of this investigation indicate that tolvaptan in combination with furosemide provides an adequate diuretic for fluid management subsequent to LDLT without causing adverse effects.

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.

Recent advances in ABO incompatible liver transplantation

Liver transplantation has become the best way to cure patients with end-stage liver disease. Due to the shortage of donor organs worldwide and being unable to obtain matched donor liver, most patients with severe hepatic failure lose the chance of operation or even die. As a result, ABO incompatible (ABO-I) liver transplantation has become a choice to save the endangered life. However, compared with ABO compatible liver transplantation, ABO-I liver transplantation is more prone to cause severe antibody mediated rejection (AMR), biliary complications, infection, thrombotic microangiopathy, and acute kidney injury. Consequently, its clinical application is limited. In recent years, with the progress of AMR prevention strategies such as immunoabsorption, plasmapheresis, rituximab, splenectomy, intravenous immunoglobulin, and graft perfusion, the clinical efficacy of ABO-I liver transplantation has been significantly improved, although it still faces the challenge of how to prevent and control AMR and postoperative complications.

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.

First successful perinatal management of pregnancy after ABO-incompatible liver transplantation

Many papers have reported on pregnancy and delivery after liver transplantation, but there have been no reports on pregnancy after ABO-incompatible liver transplantation. This paper reports the first successful pregnancy and delivery of a newborn after ABO-incompatible liver transplantation for fulminant hepatic failure. The patient was a 39-year-old female. She had an ABO-incompatible liver transplantation, donated from her husband, due to subacute fulminant hepatitis of unknown etiology. She was taking tacrolimus, methylprednisolone, and mizoribine orally for the maintenance of immunosuppression at the time of discharge. She was discharged uneventfully on postoperative day 38 without any rejection episodes. At 1 year and 6 mo after transplantation, she indicated a wish to become pregnant. Therefore, treatment with mycophenolate mofetil was interrupted at that time. After two miscarriages, she finally became pregnant and delivered transvaginally 3 years after the transplantation. All of the pregnancies were conceived naturally. The newborn was female with a birth weight of 3146 g; the Apgar scores were 9 and 10. Delivery was performed smoothly, and the newborn exhibited no malformations. The mother and the newborn were discharged uneventfully. We suggest that pregnancy is possible for recipients after ABO-incompatible liver transplantation.

Single-Center Experience of ABO-Incompatible Living-Donor Liver Transplantation With a New Simplified Intravenous Immunoglobulin Protocol: A Propensity Score-Matching Analysis

The outcomes of patients who undergo ABO-incompatible (ABO-I) living-donor liver transplantation (LDLT) have markedly improved as strategies have become more innovative and advanced. Here, we describe 25 cases of ABO-I LDLT with a simplified protocol and compare the outcomes to those of ABO-compatible LDLT. We analyzed outcomes via a retrospective review of 182 adult LDLT cases including 25 ABO-I LDLTs from January 2011 to December 2014. Propensity scoring was used to compare the groups. The desensitization protocol included plasma exchange, rituximab, and intravenous immunoglobulin without local infusion therapy. The triple immunosuppression protocol consisted of tacrolimus and steroids with mycophenolate mofetil; a splenectomy was not routinely performed. The median age of recipients was 51 years (range, 35-66 years), and the median mean Model for End-Stage Liver Disease (MELD) score was 15 (range, 7-37). The initial ranges of isoagglutinin IgM and IgG titers were 1:1 to 1:256 and 1:4 to 1:2048, respectively. There were no significant differences in patient demographics or perioperative variables between the groups. Although significant rebound elevation in anti-ABO antibody during the postoperative period was observed in 3 cases, neither C4d staining nor clinical signs of antibody-mediated rejection was apparent in these cases. No diffuse intrahepatic biliary stricture was encountered in any ABO-I LDLT patient within a mean follow-up of 22.6 ± 17.2 months. Moreover, no significant difference in overall or graft survival was observed between the groups. ABO-I LDLT can be performed safely under this new simplified protocol and may be proposed when ABO-compatible donors are unavailable.

Comparison of acute kidney injury between ABO-compatible and ABO-incompatible living donor liver transplantation: A propensity matching analysis

The anti-CD20 monoclonal antibody rituximab has significantly decreased the prevalence of antibody-mediated rejection of ABO-incompatible (ABOi) living donor liver transplantation (LDLT). However, little is known about acute kidney injury (AKI) following ABOi LDLT. The aim of this study was to identify the incidence of AKI in ABOi LDLT and compare it with that of ABO-compatible (ABOc) LDLT. We retrospectively collected and analyzed the data of 1617 patients who underwent liver transplant surgery from November 2008 to December 2014. Risk factors for AKI were investigated using multivariate regression analysis. In 271 ABOi LDLTs, AKI occurred in 184 (67.9%) according to Kidney Disease: Improving Global Outcomes criteria. After propensity score matching, the incidence of AKI was significantly higher after ABOi LDLT than after ABOc LDLT (67.0% versus 48.2%; P < 0.001). Furthermore, the intensive care unit stay (P = 0.01) was significantly prolonged, but there were no significant differences in mortality (P = 0.74), graft failure (P = 0.32), and postoperative dialysis (P = 0.74) between the 2 groups. Hemoglobin level and operation time were independent risk factors for AKI following ABOi LDLT. In conclusion, the incidence of AKI is higher in ABOi LDLT than ABOc LDLT. However, the impact of AKI on postoperative outcomes was not marked in our study. Therefore, ABOi LDLT in selected patients is promising with apparent good graft and survival outcomes. Liver Transplantation 22 1656-1665 2016 AASLD.

ABO-Incompatible Living Donor Liver Transplantation in Focus of Antibody Rebound

BACKGROUND

Living donor liver transplantation (LDLT) is an option to expand the donor organ pool for patients with life-threatening diseases who cannot be supplied with a cadaver organ. Next to the donor risks, complications after ABO-incompatible LDLT (ABOi LDLT) in the recipient are subject to controversial discussion. Improvement in ABOi graft survival rates have been achieved with plasma treatment procedures (PTP) and immunosuppression but antibody-mediated rejection (AMR) and graft loss still occur.

METHODS

Since 2008, we have prepared 10 patients for ABOi LDLT. Seven of the 10 patients for transplantation had hepatocellular carcinoma (HCC).

RESULTS

All patients underwent PTP before and after ABOi LDLT as well as immunosuppression according to the treatment schedule. We did not use anti-CD20 monoclonal antibodies in the transplant setting. We transplanted 6 of 10 preconditioned patients. After 3 years, 5 of the 6 transplanted patients were still alive.

CONCLUSION

Even if B-cell depletion with anti-CD 20 treatment in the setting of ABOi LDLT is commonly accepted, our center successfully administered only quadruple drug immunosuppression combined with PTP. Especially patients with HCC had a high titer increment also pre-transplantation and were at high risk for arterial thrombosis and graft loss.

Efficacy of single, extended and goal directed immunoadsorption in ABO incompatible living related donor liver transplantation

BACKGROUND

Liver transplantation is one of the solid organs most commonly being transplanted across the world. The indications, affordability and accessibility have grown manifold. To increase the donor pool, inclusion of ABO incompatible liver donors is being considered. To enhance the graft functioning and survival, immunoadsorption apheresis to reduce the ABO hemagglutination titres are on the rise.

CASE REPORT

We report three cases ABO incompatible liver transplantation with immunoadsorption protocol. The patients were in poor general condition with Child-Turcotte-Pugh (CTP) class 'C' and there were no suitable ABO compatible grafts at the time. For all three cases, immunosuppressive protocol consisted of induction with Rituximab, followed by tacrolimus, mycophenolate mofetil and corticosteroids. The third patient received basiliximab for induction, in addition to the above protocol. First 2 patients received 1 immunoadsorption (IA) session with Glycosorb ABO® system (Glycorex AB, Sweden), pre-operatively. The third patient received 2 IA sessions pre-operatively. Baseline IgM plus IgG titres were 1024; 64 and 1024 for anti-B, anti-A and anti-B for patient 1, 2 and 3 respectively. Target pre-operative antibody titre was ≤16. Average post-operative length of stay was 17.3 days. There were no acute rejection. None of them, required any post-operative plasma exchange.

CONCLUSION

Immunoadsorption is effective in reducing hemagglutination titres in recipients of ABO incompatible donor liver.

Current techniques for AB0-incompatible living donor liver transplantation

For a long time, it was considered medical malpractice to neglect the blood group system during transplantation. Because there are far more patients waiting for organs than organs available, a variety of attempts have been made to transplant AB0-incompatible (AB0i) grafts. Improvements in AB0i graft survival rates have been achieved with immunosuppression regimens and plasma treatment procedures. Nevertheless, some grafts are rejected early after AB0i living donor liver transplantation (LDLT) due to antibody mediated rejection or later biliary complications that affect the quality of life. Therefore, the AB0i LDLT is an option only for emergency situations, and it requires careful planning. This review compares the treatment possibilities and their effect on the patients’ graft outcome from 2010 to the present. We compared 11 transplant center regimens and their outcomes. The best improvement, next to plasma treatment procedures, has been reached with the prophylactic use of rituximab more than one week before AB0i LDLT. Unfortunately, no standardized treatment protocols are available. Each center treats its patients with its own scheme. Nevertheless, the transplant results are homogeneous. Due to refined treatment strategies, AB0i LDLT is a feasible option today and almost free of severe complications.

Risk factor for ischemic-type biliary lesion after ABO-incompatible living donor liver transplantation

AIM: To evaluate the risk factors for ischemic-type biliary lesion (ITBL) after ABO-incompatible (ABO-I) adult living donor liver transplantation (ALDLT).

METHODS: Among 141 ALDLTs performed in our hospital between 2008 and 2014, 27 (19%) were ABO-I ALDLT and 114 were ABO-identical/compatible ALDLT. In this study, we extensively analyzed the clinico-pathological data of the 27 ABO-I recipients to determine the risk factors for ITBL after ABO-I ALDLT. All ABO-I ALDLT recipients underwent an identical B-cell depletion protocol with preoperative rituximab, plasma exchange (PE), and operative splenectomy. The median follow-up period after transplantation was 26 mo. The clinical outcomes of the 27 ABO-I ALDLT recipients were compared with those of 114 ABO-identical/compatible ALDLT recipients.

RESULTS: ITBL occurred in four recipients (14.8%) between 45 and 112 d after ABO-I ALDLT. The overall survival rates were not different between ABO-I ALDLT and ABO-identical/compatible ALDLT (P = 0.303). Among the ABO-I ALDLT recipients, there was no difference between patients with ITBL and those without ITBL in terms of B-cell and T-cell count, serum isoagglutinin titers, number of PEs, operative time and transfusion, use of graft infusion therapy, or number of remnant B-cell follicles and plasma cells in the spleen. However, the perioperative NK cell counts in the blood of patients with ITBL were significantly higher than those in the patients without ITBL (P < 0.05). Preoperative NK cell count > 150/μL and postoperative NK cell count > 120/μL were associated with greater relative risks (RR) for development of ITBL (RR = 20 and 14.3, respectively, P < 0.05).

CONCLUSION: High NK cell counts in a transplant recipient’s blood are associated with ITBL after ABO-I ALDLT. Further research is needed to elucidate the molecular mechanism of NK cell involvement in the development of ITBL.

The optimal immunosuppressive protocol for the portal vein infusion of PGE1 and methylprednisolone in pediatric liver transplantation for fulminant hepatic failure of unknown etiology

The outcome of LTx in pediatric patients with FHF of unknown etiology remains inferior to that of LTx in pediatric patients with cholestatic diseases. A higher incidence of steroid-resistant severe rejection has been increasingly recognized among the responsible factors. We assessed the efficacy of the administration of steroids and PGE1 via PVI in the management of LTx for FHF in pediatric patients. In our early cohort (1995-2007), seven patients who underwent LTx for FHF of unknown etiology were treated with conventional immunosuppressive therapy (calcineurin inhibitor and a steroid). Seven of eight grafts (one patient underwent re-LTx) sustained CV and/or CPV associated with ACR, and four patients died of a graft failure or infectious complications that were associated with the treatment for rejection. Of note, the pathological incidence of CV/CPV was significantly higher in recipients with FHF of unknown etiology than in recipients with biliary cholestatic disease during the same study period (87.5% vs. 13.7%, p < 0.00001). From 2008, three patients underwent LTx for cryptogenic FHF with PVI and conventional IS. PVI was well tolerated, and no relevant severe complications were observed. More strikingly, the patients who received PVI overcame biopsy-proven immunological events and are all currently doing well with excellent graft function after more than five yr. We conclude that PVI is technically safe and effective for preventing severe rejection in pediatric patients who undergo LTx for FHF of unknown etiology and that it does not increase the risk of fatal infectious complications.

Liver transplantation with deceased ABO-incompatible donors is life-saving but associated with increased risk of rejection and post-transplant complications

ABO-incompatible (ABOi) liver transplantation (LT) with deceased donor organs is performed occasionally when no ABO-compatible (ABOc) graft is available. From 1996 to 2011, 61 ABOi LTs were performed in Oslo and Gothenburg. Median patient age was 51 years (range 13-75); 33 patients were transplanted on urgent indications, 13 had malignancy-related indications, and eight received ABOi grafts for urgent retransplantations. Median donor age was 55 years (range 10-86). Forty-four patients received standard triple immunosuppression with steroids, tacrolimus, and mycophenolate mofetil, and forty-four patients received induction with IL-2 antagonist or anti-CD20 antibody. Median follow-up time was 29 months (range 0-200). The 1-, 3-, 5-, and 10-year Kaplan-Meier estimates of patient survival (PS) and graft survival (GS) were 85/71%, 79/57%, 75/55%, and 59/51%, respectively, compared to 90/87%, 84/79%, 79/73%, and 65/60% for all other LT recipients in the same period. The 1-, 3-, 5-, and 10-year GS for A2 grafts were 81%, 67%, 62%, and 57%, respectively. In conclusion, ABOi LT performed with non-A2 grafts is associated with inferior graft survival and increased risk of rejection, vascular and biliary complications. ABOi LT with A2 grafts is associated with acceptable graft survival and can be used safely in urgent cases.

Management of immunosuppressant agents following liver transplantation: Less is more

Immunosuppression in organ transplantation was revolutionary for its time, but technological and population changes cast new light on its use. First, metabolic syndrome (MS) is increasing as a public health issue, concomitantly increasing as an issue for post-orthotopic liver transplantation patients; yet the medications regularly used for immunosuppression contribute to dysfunctional metabolism. Current mainstay immunosuppression involves the use of calcineurin inhibitors; these are potent, but nonspecifically disrupt intracellular signaling in such a way as to exacerbate the impact of MS on the liver. Second, the impacts of acute cellular rejection and malignancy are reviewed in terms of their severity and possible interactions with immunosuppressive medications. Finally, immunosuppressive agents must be considered in terms of new developments in hepatitis C virus treatment, which undercut what used to be inevitable viral recurrence. Overall, while traditional immunosuppressive agents remain the most used, the specific side-effect profiles of all immunosuppressants must be weighed in light of the individual patient.

Liver transplantation in acute liver failure: A challenging scenario

Acute liver failure is a critical medical condition defined as rapid development of hepatic dysfunction associated with encephalopathy. The prognosis in these patients is highly variable and depends on the etiology, interval between jaundice and encephalopathy, age, and the degree of coagulopathy. Determining the prognosis for this population is vital. Unfortunately, prognostic models with both high sensitivity and specificity for prediction of death have not been developed. Liver transplantation has dramatically improved survival in patients with acute liver failure. Still, 25% to 45% of patients will survive with medical treatment. The identification of patients who will eventually require liver transplantation should be carefully addressed through the combination of current prognostic models and continuous medical assessment. The concerns of inaccurate selection for transplantation are significant, exposing the recipient to a complex surgery and lifelong immunosuppression. In this challenging scenario, where organ shortage remains one of the main problems, alternatives to conventional orthotopic liver transplantation, such as living-donor liver transplantation, auxiliary liver transplant, and ABO-incompatible grafts, should be explored. Although overall outcomes after liver transplantation for acute liver failure are improving, they are not yet comparable to elective transplantation.

Case-matched comparison of ABO-incompatible and ABO-compatible living donor liver transplantation

BACKGROUND

ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) has a high success rate. There are few detailed comparisons regarding biliary complications, infective complications and patient survival between ABO-compatible (ABO-C) and ABO-I LDLT. The aim was to compare the outcomes of ABO-I LDLT with those of ABO-C LDLT using the matched-pairs method.

METHODS

Patients who underwent ABO-I LDLT procedures between 2010 and 2013 were studied. They were matched for significant variables with patients who had ABO-C LDLT (1:2 matching).

RESULTS

Forty-seven ABO-I LDLT procedures were included. Ninety-four patients who had ABO-C LDLT were selected as a comparator group. The incidence of cytomegalovirus, bacterial and fungal infections during the first 3 months was similar after ABO-I LDLT and ABO-C LDLT (85 versus 76 per cent, 28 versus 37 per cent, and 13 versus 20 per cent, respectively). Antibody-mediated rejection occurred after two procedures within 2 weeks of transplantation, but liver function improved with plasma exchange in both patients. There were no differences in the rate of acute rejection and biliary complications between ABO-I and ABO-C groups (P = 0.478 and P = 0.511 respectively). Three patients who had ABO-I LDLT developed diffuse intrahepatic biliary complications and progressed to graft failure. The 1-, 2- and 3-year patient survival rates after ABO-I LDLT and ABO-C LDLT were 89 versus 87 per cent, 85 versus 83 per cent, and 85 versus 79 per cent, respectively.

CONCLUSION

The short-term outcomes of ABO-I LDLT were comparable to those of ABO-C LDLT in this study. ABO-I LDLT is an effective and safe transplant option with the potential to expand the pool of live donors.

Results of ABO-incompatible liver transplantation using a simplified protocol at a single institution

BACKGROUND

Because of the development of various desensitization strategies, ABO-incompatible (ABOi) living donor liver transplantation (LDLT) has become a feasible option for patients with end-stage liver disease. However, there has been no united desensitization protocol for ABOi LDLT. We analyzed the outcomes after establishment of simplified protocol without splenectomy, intravenous immunoglobulin, and local infusion therapy.

METHODS

We analyzed 19 ABOi LDLT cases that had been performed between January 2012 and December 2013, without splenectomy and local infusion. We used a single dose of rituximab (375 mg/m(2)) 10 days before transplantation and several series of plasma exchange according to the recipients' iso-agglutinin titer-to-target titer ratio of 1:32.

RESULTS

Nineteen recipients received ABOi LTs from living donors. The mean initial immunoglobulin (Ig) M and IgG anti-ABO titers were 76.63 ± 78.81 (range, 8∼256) and 162.53 ± 464.1 (0∼2048). We performed preoperative plasma exchange to 16 recipients (mean number of sessions, 3.58; range, 1-10). After surgery, 9 patients received plasma exchange (mean, 1.84; range 1∼14). One death occurred as the result of pneumonia (5.3%). There were 4 cases of acute rejections (21.1%), and all of them were treated successfully with steroid pulse or thymoglobulin. Antibody-mediated rejection and graft failure did not occur. Six cases of postoperative complications (31.6%) occurred, including 3 cases of infections. There were 2 cases of biliary anastomotic stricture (10.5%) and 1 case of portal vein stenosis (5.3%).

CONCLUSIONS

ABOi LDLT with the use of simplified protocol can be safely performed without increased risk of antibody-mediated rejection and other complications.

Development and Validation of a Novel Fibrosis Marker in Biliary Atresia during Infancy

OBJECTIVES

Most biliary atresia (BA) patients suffer from liver fibrosis and often require liver transplantation. The aim of this study was to develop and validate a novel fibrosis marker for BA patients aged <1 year-the infant BA liver fibrosis (iBALF) score-subsequent to the previously reported fibrosis marker for BA patients aged ≥1 year.

METHODS

From three institutions for pediatric surgery, BA patients and their native liver histology examinations performed at the age of <1 year were retrospectively identified and assigned to a development cohort (58 patients and 73 examinations) or validation cohort (92 patients and 117 examinations) according to their institutions. Histological fibrosis stages (F0-F4), blood test results, and clinical information at the time of liver histology examination were reviewed. The iBALF score was determined using multivariate ordered logistic regression analysis and was assessed for its associations with histological fibrosis stages.

RESULTS

The iBALF score equation was composed of natural logarithms, including serum total bilirubin level, blood platelet counts, and days of age. The score revealed a strong correlation with fibrosis stage (r=0.80 and 0.73 in the development and validation cohorts, respectively; P<0.001). The areas under the receiver-operating characteristic curves for diagnosing each fibrosis stage were 0.86-0.94 in the development cohort and 0.86-0.90 in the validation cohort (P<0.001), indicating good diagnostic power. In addition, no patient with an iBALF score >6 (equivalent to F4) at the initial surgery survived with their native liver at 1 year of age (n=9).

CONCLUSIONS

The iBALF score that was developed was a good noninvasive marker of native liver fibrosis for BA patients aged <1 year.

Helicobacter cinaedi bacteremia with cellulitis after ABO-incompatible living-donor liver transplantation: Case report

Helicobacter cinaedi (H. cinaedi), a Gram-negative spiral-shaped bacterium, is an enterohepatic non-Helicobacter pylori Helicobacter species. We report the first case of H. cinaedi bacteremia with cellulitis after liver transplantation. A 48-year-old male, who had been a dog breeder for 15 years, underwent ABO-incompatible living-donor liver transplantation for hepatitis C virus-induced decompensated cirrhosis using an anti-hepatitis B core antibody-positive graft. The patient was preoperatively administered rituximab and underwent plasma exchange twice to overcome blood type incompatibility. After discharge, he had been doing well with immunosuppression therapy comprising cyclosporine, mycophenolate mofetil, and steroid according to the ABO-incompatible protocol of our institution. However, 7 mo after transplantation, he was admitted to our hospital with a diagnosis of recurrent cellulitis on the left lower extremity, and H. cinaedi was detected by both blood culture and polymerase chain reaction analysis. Antibiotics improved his symptoms, and he was discharged at day 30 after admission. Clinicians should be more aware of H. cinaedi in immunocompromised patients, such as ABO-incompatible transplant recipients.

Fourteen successful consecutive cases of ABO-incompatible living donor liver transplantation: new simplified intravenous immunoglobulin protocol without local infusion therapy

Since various innovative strategies including local infusion therapy and rituximab have been introduced, the survivals and outcomes of recipients in ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) have remarkably improved. Thus, ABO-I LDLT can be a feasible therapeutic option for the patient with end-stage liver disease if an ABO-compatible donor is not available. Although most ABO-I protocols are based on rituximab, plasma exchange, and local infusion therapy, treatment strategies have been changing according to a center's preference or their results. Nonetheless, the consensus of the ABO-I LDLT protocol remains undetermined. Herein, we present our experience with new simple ABO-I LDLT protocol and the excellent results for 14 patients from January 2011 to May 2013. All patients were administrated a single dose of rituximab over 7 days before transplantation followed by plasma exchange to lower anti-ABO antibody titer ≤32. The basic immunosuppression protocol consisted of tacrolimus and steroids with mycophenolate mofetil starting 3 days before transplantation. Splenectomy was not performed routinely and local infusion therapy was not applied at the postoperative period. Instead, the patients received intravenous immunoglobulin (IVIG) after LDLT on days 1, 3, and 5. Neither antibody-mediated rejection nor biliary stricture were encountered in the patients, with a mean follow-up of 16.27 ± 9.4 months. This new simplified ABO-I LDLT protocol seems to prevent antibody-mediated rejection and could be considered as the safe and effective modality to overcome the ABO blood-type barrier in LDLT.

Kinetics of B, T, NK lymphocytes and isoagglutinin titers in ABO incompatible living donor liver transplantation using rituximab and basiliximab

BACKGROUND

The kinetics of isoagglutinin titers and lymphocyte subpopulations including B, T, and natural killer (NK) cells after ABO incompatible (ABO-I) living donor liver transplantation (LDLT) have not been evaluated.

METHODS

From January 2012 to July 2013, consecutive ABO-I LDLT patients were enrolled at the National Cancer Center. Our desensitizing protocol included rituximab, plasma exchanges, basiliximab, and intravenous immune globulin without splenectomy.

RESULTS

Twenty patients (14 males, 6 females) underwent ABO-I LDLT due to HCC (n=15) or liver cirrhosis (n=5). There was no hyperacute and antibody-mediated rejection. The isoagglutinin titers were effectively lowered less than 1:16 before operation. CD 19+ B cells were rapidly eliminated after rituximab and suppressed during 6months postoperatively. CD3+ and CD4+ T cells were elevated higher than CD8+ T cells. CD4/CD8 ratio was increased during first 1month postoperatively and decreased thereafter. CD16+CD56+ NK cells were lowered and restored after 4months of LDLT. Among 15 patients with HCC, 5 patients (33.3%) experienced early tumor recurrence (1/8 within Milan and 4/7 beyond Milan).

CONCLUSIONS

Our protocol showed effective results in preventing antibody-mediated rejection and suppressing B lymphocytes. Application to advanced hepatocellular carcinoma should be considered due to decreased natural immunity after ABO-I LDLT.

Cascade plasmapheresis (CP) as a preconditioning regime in ABO-incompatible live related donor liver transplants (ABOi-LDLT)

Background

ABO-incompatible live donor liver transplant (ABOi-LDLT) is being widely done to bridge the gap of demand and supply of organs. Different desensitization regimes are being used to reduce titer of blood group antibodies for successful transplant and accommodation of graft. The authors used cascade plasmapheresis (CP) to bring down titer of naturally occurring blood group antibody to 16 or lower.

Material and methods

Four recipients of ABOi-LDLT were of blood groups O, O, B, and B while donors were of blood groups B, A, AB, and AB, respectively. Desensitization protocol included immunosuppressive drugs and plasmapheresis. CP consisted of separating patient’s plasma as the first step and passing it through pore size based filter column as the second step. The first step was performed using disposable kit (PL1, Fresenius Kabi, Germany) with minor modification on apheresis equipment COM.TEC (Fresenius Kabi, Germany). Pore size based filter column used was 2A column (Evaflux, Kawasumi Laboratories, Japan). Blood group antibody titer (immunoglobulin G (IgG)) was done by column agglutination technology (Ortho-Clinical Diagnostics).

Results

Cases 1, 2, 3, and 4 with pre-CP titer of 1,024, 512, 32, and 64 required four, three, one, and one CP procedures, respectively. No signs of antibody-mediated rejection were exhibited on histopathological evaluation by any of the patients. Successful organ engraftment occurred as documented by post-operative liver function tests and liver biopsy.

Conclusion

Cascade plasmapheresis offers a cost-effective and efficient way to decrease blood group antibody titer and helps in successful transplant.

Biliary stricture is the only concern in ABO-incompatible adult living donor liver transplantation in the rituximab era

BACKGROUND & AIMS

With the introduction of rituximab prophylaxis, the survival of ABO-incompatible (ABOi) adult living donor liver transplant (ALDLT) has been strikingly improved due to the decreased incidence of antibody-mediated rejection. However, biliary stricture (BS) related to ABO incompatibility remains an unresolved concern.

METHODS

Excluding 105 dual graft ALDLTs, 1102 ALDLT cases including 142 ABOi recipients were included in this study. The desensitization protocol for overcoming the ABO blood group barrier comprised pretransplant plasma exchange, and rituximab (300-375 mg/m(2) BSA).

RESULTS

The mean follow-up period was 34.2 ± 15.4 months. The cumulative graft and patient survival rates were comparable in the two groups. The 1- and 3-year BS-free survival rates of ABOi ALDLT were 81.5 and 79.0%, respectively, lower than those of ABOc ALDLT (87.6 and 85.7%, respectively, p=0.022). In the risk factor analysis, diameter of graft bile duct opening <5mm, antecedent acute cellular rejection, and ABO incompatibility were independent risk factors for BS. Diffuse intrahepatic biliary stricture (DIHBS) exclusively occurred in 12 patients (8.5%) receiving ABOi ALDLT. The deaths of 3 patients and 4 cases of re-transplantation were related to DIHBS. Graft and patient survival rates were significantly reduced in ABOi ALDLT recipients with DIHBS. However, we failed to identify any significant risk factors for DIHBS.

CONCLUSIONS

The incidence of BS in ABOi ALDLT is higher than in ABOc, mainly due to the fact of DIHBS which significantly affected survival outcomes. To predict and prevent DIHBS, we need further studies to identify significant risk factors.

ABO-incompatible living donor liver transplantation without graft local infusion and splenectomy

BACKGROUND

Graft local infusion and splenectomy in ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) are associated with high rates of operative complications.

METHODS

Consecutive ABO-I LDLT patients treated at the National Cancer Centre between January 2012 and February 2013 were identified. The protocol for ABO-I LDLT at the study centre included the administration of rituximab (300 mg/m(2)) at 2 weeks preoperatively, followed by plasma exchanges (target isoagglutinin titre: ≤ 1:8), basiliximab (20 mg on the day of surgery and on postoperative day 4), and i.v. immunoglobulin (0.8 g/kg on postoperative days 1 and 4) without graft local infusion or splenectomy.

RESULTS

Fifteen patients (11 men and four women) who underwent transplantation for liver cirrhosis (n = 3) or hepatocellular carcinoma (n = 12) were identified. These included 13 patients with hepatitis B virus infection, one with hepatitis C virus infection and one with alcoholic cirrhosis. The mean age, mean Model for End-stage Liver Disease (MELD) score and mean graft-to-recipient weight ratio (GRWR) of these patients was 51.8 years, 11.5 and 0.84, respectively. The median isoagglutinin titre before plasma exchange was 1:32 (range: 1:4 to 1:256). There were no hyperacute or antibody-mediated rejections. No bacterial or fungal infections were observed. Complications included herpes zoster viral infection in one patient, postoperative bleeding in one patient and extrahepatic biliary stricture in three patients.

CONCLUSIONS

This simplified ABO-I LDLT protocol showed good graft outcomes without immunologic failure or serious infections.

Challenges in living donor liver transplantation

Living donor liver transplantation is a procedure that has waned in its application over the past decade but remains a beneficial procedure for properly selected candidates. This review discusses some of the newer, relevant studies in the field, focusing on outcomes with hepatocellular carcinoma, ABO-incompatible transplant, and issues in donor complications and safety.

A modified protocol with rituximab and intravenous immunoglobulin in emergent ABO-incompatible liver transplantation for acute liver failure

BACKGROUND

The established procedure for ABO-incompatible liver transplantation (ABO-I LT) was too complicated to be used in case of emergency. We developed a protocol consisting of rituximab and intravenous immunoglobulin (IVIG) for ABO-I LT in patients with acute liver failure (ALF).

METHODS

The data from 101 patients who had undergone liver transplantation (LT) for ALF were retrospectively analyzed. The patients were divided into two groups: ABO-compatible liver transplantation group (ABO-C LT, n=66) and ABO-I LT group (n=35). All the patients in the ABO-I LT group received a single dose of rituximab (375 mg/m2) and IVIG (0.4 g/kg per day) at the beginning of the operation. IVIG was administered for 10 consecutive days after LT. Plasma exchange, splenectomy and graft local infusion were omitted in the protocol. Quadruple immunosuppressive therapy including basiliximab, corticosteroids, tacrolimus and mycophenolatemofetil was used to reinforce immunosuppression.

RESULTS

The 3-year cumulative patient survival rates in the ABO-I LT and ABO-C LT groups were 83.1% and 86.3%, respectively (P>0.05), and the graft survival rates were 80.0% and 86.3%, respectively (P>0.05). Two patients (5.7%) suffered from antibody-mediated rejection in the ABO-I LT group. Other complications such as acute cellular rejection, biliary complication and infection displayed no significant differences between the two groups.

CONCLUSIONS

The simplified treatment consisting of rituximab and IVIG prevented antibody-mediated rejection for LT of blood-type incompatible patients. With this treatment, the patients did not need plasma exchange, splenectomy and graft local infusion. This treatment was safe and efficient for LT of the patients with ALF.