Validation and performance of three scoring systems for predicting primary non-function and early allograft failure after liver transplantation

Background: Primary non-function(PNF) and early allograft failure(EAF) after liver transplantation(LT) seriously affect patient outcomes. In clinical practice, effective prognostic tools for early identifying recipients at high risk of PNF and EAF were urgently needed. Recently, the Model for Early Allograft Function(MEAF), PNF score by King's College(King-PNF) and Balance-and-Risk-Lactate(BAR-Lac) score were developed to assess the risks of PNF and EAF. This study aimed to externally validate and compare the prognostic performance of these three scores for predicting PNF and EAF. Methods: A retrospective study included 720 patients with primary LT between January 2015 and December 2020. MEAF, King-PNF and BAR-Lac scores were compared using receiver operating characteristic(ROC) and the net reclassification improvement(NRI) and integrated discrimination improvement(IDI) analyses. Results: Of all 720 patients, 28(3.9%) developed PNF and 67(9.3%) developed EAF in 3 months. The overall early allograft dysfunction(EAD) rate was 39.0%. The 3-month patient mortality was 8.6% while 1-year graft-failure-free survival was 89.2%. The median MEAF, King-PNF and BAR-Lac scores were 5.0(3.5–6.3),-2.1(-2.6 to-1.2), and 5.0(2.0–11.0), respectively. For predicting PNF, MEAF and King-PNF scores had excellent area under curves(AUCs) of 0.872 and 0.891, superior to BAR-Lac(AUC = 0.830). The NRI and IDI analyses confirmed that King-PNF score had the best performance in predicting PNF while MEAF served as a better predictor of EAD. The EAF risk curve and 1-year graft-failure-free survival curve showed that King-PNF was superior to MEAF and BAR-Lac scores for stratifying the risk of EAF. Conclusions: MEAF, King-PNF and BAR-Lac were validated as practical and effective risk assessment tools of PNF. King-PNF score outperformed MEAF and BAR-Lac in predicting PNF and EAF within 6 months. BAR-Lac score had a huge advantage in the prediction for PNF without post-transplant variables. Proper use of these scores will help early identify PNF, standardize grading of EAF and reasonably select clinical endpoints in relative studies.

L-GrAFT_(7) has High Accuracy in Predicting Early Allograft Failure after Liver Transplantation: A Multicenter Cohort Study in China

Background and Aims:Increasing utilization of extended criteria donor leads to an increasing rate of early allograft failure after liver transplantation.However,consensus of definition of early allograft failure is lacking.Methods:A retrospective,multicenter study was performed to validate the Liver Graft Assessment Following Transplantation(L-GrAFT)risk model in a Chinese cohort of 942 adult patients undergoing primary liver transplantation at three Chinese centers.L-GrAFT(L-GrAFT7 and L-GrAFT10)was compared with existing models:the Early Allograft Failure Simplified Estimation(EASE)score,the model of early allograft function(MEAF),and the Early Allograft Dysfunction(EAD)model.Univariate and multivariate logistic regression were used to find risk factors of L-GrAFT high-risk group.Results:L-GrAFT7 had an area under the curve of 0.85 in predicting 90-day graft survival,significantly superior to MEAF[area under the curve(AUC=0.78,p=0.044)]and EAD(AUC=0.78,p=0.006),while there was no statistical significance between the predicting abilities of L-GrAFT7 and EASE(AUC=0.84,p>0.05).Furthermore,L-GrAFT7 maintains good predicting ability in the subgroup of high-donor risk index(DRI)cases(AUC=0.83 vs.MEAF,p=0.007 vs.EAD,p=0.014)and recipients of donors after cardiac death(AUC=0.92 vs.EAD,p<0.001).Through multivariate analysis,pretransplant bilirubin level,units of packed red blood cells,and the DRI score were selected as independent risk factors of a L-GrAFT7 high-risk group.Conclusions:The accuracy of L-GrAFT7 in predicting early allograft failure was validated in a Chinese multicenter cohort,indicating that it has the potential to become an accurate endpoint of clinical practice and transitional study of machine perfusion.

Thrombotic microangiopathy after kidney transplantation: Expanding etiologic and pathogenetic spectra

Thrombotic microangiopathy(TMA)is an uncommon but serious complication that not only affects native kidneys but also transplanted kidneys.This review is specifically focused on post-transplant TMA(PT-TMA)involving kidney transplant recipients.Its reported prevalence in the latter population varies from 0.8%to 14%with adverse impacts on both graft and patient survival.It has many causes and associations,and the list of etiologic agents and associations is growing constantly.The pathogenesis is equally varied and a variety of pathogenetic pathways lead to the development of microvascular injury as the final common pathway.PT-TMA is categorized in many ways in order to facilitate its management.Ironically,more than one causes are contributory in PT-TMA and it is often difficult to pinpoint one particular cause in an individual case.Pathologically,the hallmark lesions are endothelial cell injury and intravascular thrombi affecting the microvasculature.Early diagnosis and classification of PT-TMA are imperative for optimal outcomes but are challenging for both clinicians and pathologists.The Banff classification has addressed this issue and has developed minimum diagnostic criteria for pathologic diagnosis of PT-TMA in the first phase.Management of the condition is also challenging and still largely empirical.It varies from simple maneuvers,such as plasmapheresis,drug withdrawal or modification,or dose reduction,to lifelong complement blockade,which is very expensive.A thorough understanding of the condition is imperative for an early diagnosis and quick treatment when the treatment is potentially effective.This review aims to increase the awareness of relevant stakeholders regarding this important,potentially treatable but under-recognized cause of kidney allograft dysfunction.

Late complications of pancreas transplant

To summarize the long-term complications after pancreas transplantation that affect graft function,a literature search was carried out on the long-term complications of pancreatic transplantation,namely,complications from postoperative 3rd mo onwards,in terms of loss of graft function,late infection and vascular complications as pseudoaneurysms.The most relevant reviews and studies were selected to obtain the current evidence on these topics.The definition of graft failure varies among different studies,so it is difficult to evaluate,a standardized definition is of utmost importance to know the magnitude of the problem in all worldwide series.Chronic rejection is the main cause of long-term graft failure,occurring in 10%of patients.From the 3rd mo of transplantation onwards,the main risk factor for late infections is immunosuppression,and patients have opportunistic infections like:Cytomegalovirus,hepatitis B and C viruses,Epstein-Barr virus and varicella-zoster virus;opportunistic bacteria,reactivation of latent infections as tuberculosis or fungal infections.Complete preoperative studies and serological tests should be made in all recipients to avoid these infections,adding perioperative prophylactic treatments when indicated.Pseudoaneurysm are uncommon,but one of the main causes of late bleeding,which can be fatal.The treatment should be performed with radiological endovascular approaches or open surgery in case of failure.Despite all therapeutic options for the complications mentioned above,transplantectomy is a necessary option in approximately 50%of relaparotomies,especially in lifethreatening complications.Late complications in pancreatic transplantation threatens long-term graft function.An exhaustive follow-up as well as a correct immunosuppression protocol are necessary for prevention.

Early graft failure after meniscus allograft transplantation： an unusual cause of using all-inside meniscal repair device

Meniscal allograft transplantation （MAT） may offer .an attractive alternative to restore the normal biomechanical structure of knees. The mean early failure rate （≤2 years） of MAT is approximately 10%.1-3 A successful outcome of MAT depends on the ligamentous stability of knee, limb alignment, graft types, and graft fixation methodsY Graft fixations include the meniscal horns and the peripheral rim. Techniques for fixation of the peripheral rim include sutures or a meniscal repair device such as FasT-Fix （Smith ＆ Nephew Inc, Andover, MA, USA）. Here we present an unusual case of early graft failure using FasT-Fix sutured to the peripheral rim of the graft.