Postreperfusion biopsies are useful in predicting complications after liver transplantation

Postreperfusion Liver Biopsy as Predictor of Early Graft Dysfunction and Survival After Orthotopic Liver Transplantation

BACKGROUND

Postreperfusion liver biopsy (PRB) can assess the degree of ischemia/reperfusion injury (IRI) after orthotopic liver transplantation (OLT). The influence of IRI on graft outcomes and overall survival is controversial.

AIM

To determine the correlation between the severity of IRI in PRB and overall graft and patient survival and, secondarily, to identify factors on PRB that predict poor graft outcomes.

METHODS

This is a retrospective analysis of all patients who underwent OLT using donation after brain death (DBD) with PRB. The severity of IRI in PRB was graded. Predictors of IRI were assessed using univariate and multivariate analysis and the Kaplan-Meier with log rank test for the graft and overall survival, respectively.

RESULTS

We included 280 OLTs (64.7%). The histopathological assessment of IRI severity was as follows: no IRI (N = 96, 34.3%), mild IRI (N = 65; 23.2%), moderate IRI (N = 101; 36.1%), and severe IRI (N = 18; 6.4%). The incidence rates of initial good graft function (IGGF), primary nonfunction and early allograft dysfunction (EAD) were 32.5%, 3.9%, and 18.6%, respectively. Severe IRI was associated with a lower incidence of IGGF (OR: 0.34, 95% CI 0.12-0.92; P = 0.03). Patients with severe IRI tended to have a higher incidence of EAD (33.2% vs. 18.6, P = 0.23). The cold ischemia time was an independent predictor of severe IRI on the multivariate analysis. Severe IRI was associated with poor 1- and 5-year overall survival rates (67% and 44%, respectively, compared with 84 and 68% in nonsevere IRI). Patients with severe IRI exhibited worse graft and overall survival.

CONCLUSIONS

Cold ischemia time predicts the development of severe IRI. Patients with severe IRI show worse graft and overall survival and a lower incidence of IGGF, suggesting that histopathological findings could be useful for identifying patients at high risk of worse outcomes after OLT.

Ischemia-reperfusion injury and its relationship with early allograft dysfunction in liver transplant patients

Ischemia-reperfusion injury (IRI) is believed to contribute to graft dysfunction after liver transplantation (LT). However, studies on IRI and the impact of early allograft dysfunction (EAD) in IRI grafts are limited. Histological IRI was graded in 506 grafts from patients who had undergone LT and classified based on IRI severity (no, minimal, mild, moderate, and severe). Of the 506 grafts, 87.4% had IRI (no: 12.6%, minimal: 38.1%, mild: 35.4%, moderate: 13.0%, and severe: 0.8%). IRI severity correlated with the incidence of EAD and graft survival at 6 months. Longer cold/warm ischemia time, recipient/donor hypertension, and having a male donor were identified as independent risk factors for moderate to severe IRI. Among 70 grafts with moderate to severe IRI, 42.9% of grafts developed EAD, and grafts with EAD had significantly inferior survival compared to grafts without EAD. Longer cold ischemia time and large droplet macrovesicular steatosis (≥20%) were identified as independent risk factors for EAD. Our study demonstrated that increased IRI severity was correlated with inferior short-term graft outcomes. Careful consideration of IRI risk factors during donor-recipient matching may assist in optimizing graft utilization and LT outcomes. Furthermore, identification of risk factors of IRI-associated EAD may guide patient management and possible timely graft replacement.

The impact of postreperfusion syndrome during liver transplantation using livers with significant macrosteatosis

The impact of postreperfusion syndrome (PRS) during liver transplantation (LT) using donor livers with significant macrosteatosis is largely unknown. Clinical outcomes of all patients undergoing LT with donor livers with moderate macrosteatosis (30%-60%) (N = 96) between 2000 and 2017 were compared to propensity score matched cohorts of patients undergoing LT with donor livers with mild macrosteatosis (10%-29%) (N = 96) and no steatosis (N = 96). Cardiac arrest at the time of reperfusion was seen in eight (8.3%) of the patients in the moderate macrosteatosis group compared to one (1.0%) of the patients in the mild macrosteatosis group (P = .02) and zero (0%) of the patients in the no steatosis group (P = .004). Patients in the moderate macrosteatosis group had a higher rate of PRS (37.5% vs 18.8%; P = .004), early allograft dysfunction (EAD) (76.4% vs 25.8%; P < .001), renal dysfunction requiring continuous renal replacement therapy following transplant (18.8% vs 8.3%; P = .03) and return to the OR within 30 days (24.0% vs 7.3%; P = .002), than the no steatosis group. Both long-term patient (P = .30 and P = .08) and graft survival (P = .15 and P = .12) were not statistically when comparing the moderate macrosteatosis group to the mild macrosteatosis and no steatosis groups. Recipients of LT using livers with moderate macrosteatosis are at a significant increased risk of PRS. If patients are able to overcome the initial increased perioperative risk of using these donor livers, long-term graft survival does not appear to be different than matched recipients receiving grafts with no steatosis.

A Review on the Management of Biliary Complications after Orthotopic Liver Transplantation

Orthotopic liver transplantation is the definitive treatment for end-stage liver disease and hepatocellular carcinomas. Biliary complications are the most common complications seen after transplantation, with an incidence of 10-25%. These complications are seen both in deceased donor liver transplant and living donor liver transplant. Endoscopic treatment of biliary complications with endoscopic retrograde cholangiopancreatography (commonly known as ERCP) has become a mainstay in the management post-transplantation. The success rate has reached 80% in an experienced endoscopist's hands. If unsuccessful with ERCP, percutaneous transhepatic cholangiography can be an alternative therapy. Early recognition and treatment has been shown to improve morbidity and mortality in post-liver transplant patients. The focus of this review will be a learned discussion on the types, diagnosis, and treatment of biliary complications post-orthotopic liver transplantation.

The "Skinny" on Assessment and Utilization of Steatotic Liver Grafts: A Systematic Review

The frequency at which steatotic deceased donor liver grafts are encountered will likely continue to increase. Utilization of liver grafts with moderate-to-severe steatosis for liver transplantation (LT) has been previously shown to be associated with increased rates of primary nonfunction and decreased recipient survival. In order to better inform clinical decision making and guide future research, critical evaluation of the literature on donor liver steatosis and posttransplantation outcome is needed. This literature review aims to provide the "skinny" on using deceased donor steatotic livers for LT.

Acoustic Radiation Force Impulse and Doppler Ultrasonography: Comprehensive Evaluation of Acute Rejection After Liver Transplantation

OBJECTIVES

The aim of our study was to evaluate the clinical application of color Doppler flow imaging (CDFI) and acoustic radiation force impulse (ARFI) for the diagnosis of acute rejection after liver transplantation.

METHODS

B-Mode CDFI and ARFI assessments were performed in 76 patients who underwent biopsy after liver transplantation at our institution, between October 2011 and October 2014. The study group included 56 patients with acute rejection confirmed by biopsy, with 20 patients whose liver function recovered within 1 month of transplantation forming the control group. Anteroposterior diameter of the liver, hemodynamic index (consisting of the portal vein diameter, portal vein flow velocity, and hepatic vein flow waveform), and ARFI shear wave velocity (SWV) were measured. We used logistic regression modeling and receiver operating curve to evaluate between-group differences.

RESULTS

Compared with the control group, patients with acute rejection exhibited increased anteroposterior diameter (P = .035) and change in hemodynamic index (P = .021), including increased portal vein diameter, decreased portal vein flow, and loss of triphasic waveform of hepatic vein flow. Acoustic radiation force impulse SWV was markedly increased in the acute rejection group (P < .001). The correlation r-value of measured parameters to acute rejection diagnosis was 0.253 for anterioposterior diameters, 0.271 for change in hemodynamic index, and 0.721 for increased SWV. Shear wave velocity and change in the hemodynamic index had diagnostic value, with an area under the receiver operating curve of 0.933.

CONCLUSIONS

Combining CDFI with ARFI was useful for the diagnosis of acute rejection after liver transplantation.

Histological and Clinicopathological Evaluation of Liver Allograft Biopsy: An Initial Experience of Fifty Six Biopsies

INTRODUCTION

Liver biopsy is gold standard for diagnosis of allograft dysfunction.

AIM

The aim of study was to evaluate liver allograft biopsies performed for graft dysfunction, study the pattern of injury and intensity, and timeline of occurrence of graft dysfunction.

MATERIALS AND METHODS

Retrospective study was carried out of 56 liver allograft biopsies and their histological findings with clinical presentation were correlated. Totally 56 needle liver allograft biopsies from January 1210 to July 2014, obtained from 35 patients were studied for histological and clinicopathological evaluation.

RESULTS

The mean age was 53.2±5.48 years. The most common original disease was alcoholic cirrhosis. The most common histological lesion was acute cellular rejection (ACR) in 31 (55.36%) biopsies followed by preservation-reperfusion injury (PRI) in 10 (17.86%) biopsies and drug toxicity in 8 (14.29%) biopsies. Chronic rejection was reported in 2 (3.57%) and recurrence of HCV in 3 (5.36%). Ischemic coagulative necrosis and acute cholangitis were seen in 1 (1.79 %) case each.

CONCLUSION

Alcoholic cirrhosis was the most common etiology for end stage liver disease. ACR and PRI were the major complications in liver allograft biopsies at our centre.

Donor Hepatic Steatosis and Outcome After Liver Transplantation: a Systematic Review

BACKGROUND

There is increasing need to expand availability of donor liver grafts, including steatotic livers. Steatotic liver is associated with poor outcome post-transplantation but with conflicting results in the literature. The aim of this systematic review was to evaluate the impact of steatotic livers on liver transplantation outcomes.

METHODS

An electronic search of OVID Medline and Embase databases was performed to identify clinical studies that reported outcomes of steatotic livers in liver transplantation. Data were extracted, and basic descriptive statistics were used to summarise data pooled from individual clinical studies.

RESULTS

Ninety-two articles were identified, of which 34 met the inclusion criteria, and stratified analysis were performed. There was a lack of standardised definition of primary non-function or impaired primary function amongst the studies and description of type of steatosis. Severely (>60%) steatotic grafts are associated with increased risk of poor graft function, whilst moderate-severe (>30%) steatotic grafts are associated with decreased graft survival.

CONCLUSIONS

Available evidence showed increased risk of poor graft outcome in moderate-severe steatotic livers. A large prospective multi-centred trial will be required to identify the true risks of steatotic livers. Consistent definition of primary non-function/impaired primary function and description of type of steatosis is also required.

Analysis of ischemia/reperfusion injury in time-zero biopsies predicts liver allograft outcomes

Ischemia/reperfusion injury (IRI) that develops after liver implantation may prejudice long-term graft survival, but it remains poorly understood. Here we correlate the severity of IRIs that were determined by histological grading of time-zero biopsies sampled after graft revascularization with patient and graft outcomes. Time-zero biopsies of 476 liver transplants performed at our center between 2000 and 2010 were graded as follows: nil (10.5%), mild (58.8%), moderate (26.1%), and severe (4.6%). Severe IRI was associated with donor age, donation after circulatory death, prolonged cold ischemia time, and liver steatosis, but it was also associated with increased rates of primary nonfunction (9.1%) and retransplantation within 90 days (22.7%). Longer term outcomes in the severe IRI group were also poor, with 1-year graft and patient survival rates of only 55% and 68%, respectively (cf. 90% and 93% for the remainder). Severe IRI on the time-zero biopsy was, in a multivariate analysis, an independent determinant of 1-year graft survival and was a better predictor of 1-year graft loss than liver steatosis, early graft dysfunction syndrome, and high first-week alanine aminotransferase with a positive predictive value of 45%. Time-zero biopsies predict adverse clinical outcomes after liver transplantation, and severe IRI upon biopsy signals the likely need for early retransplantation.

Endoscopic retrograde cholangiography for biliary anastomotic strictures after liver transplantation

Biliary complications after liver transplantation (LT) are an important cause of morbidity and mortality. In most cases, an anastomosis of the bile duct is performed as a duct-to-duct reconstruction, which makes endoscopic therapy with endoscopic retrograde cholangiography (ERC) feasible. Biliary anastomotic strictures (AS) are the most common cause of biliary complications. The early detection of an AS, which can sometimes be challenging given that its clinical presentation is often subtle, is of key importance to obtain high treatment success. In this review, we focus on the management of AS after LT with a special emphasis on ERC.

Tacrolimus dose requirement in pediatric liver transplantation: influence of CYP3A5 gene polymorphism

AIM

Little information is available regarding the influence of CYP3A5 genetic polymorphisms on tacrolimus dose requirement in pediatric liver transplantation.

PATIENTS & METHODS

We performed a retrospective study among 179 pediatric liver recipients grafted between 2002 and 2009 in order to determine the influence of donor CYP3A5 genotype along with clinical variables on tacrolimus daily dose requirement during the first weeks following transplantation.

RESULTS

Mean stable tacrolimus daily dose requirement was higher among children who received a liver expressing CYP3A5 (carrying the CYPA3A5*1 allele) compared with those with a liver that did not express CYP3A5 (CYP3A5*3/*3 genotype): 0.29 ± 0.20 vs 0.18 ± 0.13 mg.kg(-1).d(-1), p = 0.005, respectively. A younger recipient age and fluconazole prescription were also significantly associated with tacrolimus daily dose requirement. Time to reach stable tacrolimus therapeutic trough concentrations was prolonged among patients with a CYP3A5-expressing graft (26 vs 21 days, p = 0.04).

CONCLUSION

Donor CYP3A5 genotype partially explains tacrolimus dose requirement. Original submitted 30 January 2013; Revision submitted 2 May 2013.

Hepatic preservation injury: severity of hepatitis C recurrence and survival after liver transplantation

BACKGROUND

Preservation injury in the HCV liver transplant population has been reported to correlate with poorer survival outcomes compared to preservation injury in the non-HCV liver transplant population. However, determinants of progression to cirrhosis in HCV infection remain poorly defined in this population.

AIM

This study aimed to determine if the presence and severity of preservation injury impact the acceleration of HCV recurrence and survival after liver transplant.

METHODS

We retrospectively reviewed liver transplant HCV patients over a 10-year period. Biopsies from postoperative day 7 were assessed for preservation injury and 4- and 12-month biopsies were assessed for fibrosis. Patients with Ishak fibrosis >0.8 Units/year were considered rapid fibrosers.

RESULTS

Our study group consisted of 255 patients. The mean age was 49.3 years old, 180 (70.6 %) were male, and 221 (86.7 %) were Caucasian. The incidence of preservation injury on the 7-day biopsy was 69.0 %. A strong correlation between postoperative peak AST within the first week and preservation injury was found. The overall prevalence of rapid fibrosers at 4 months, 1 and 2 years was 47.4, 75.2, and 58.9 %, respectively. The prevalence of rapid fibrosers at 4 months, 1 and 2 years between patients with or without preservation injury was not statistically significant (p = 0.39, p = 0.46, and p = 0.53, respectively). No differences were seen between patients with and without PI in terms of patient and graft survival.

CONCLUSION

In this study, the presence and severity of preservation injury were not associated with development of rapid HCV recurrence or worsening in survival.

Implications of a positive crossmatch in liver transplantation: a 20-year review

Whether a positive crossmatch result has any relevance to liver transplantation (LT) outcomes remains controversial. We assessed the impact of a positive crossmatch result on patient and graft survival and posttransplant complications. During a 20-year period, 2723 LT procedures with crossmatch results were identified: 2479 primary transplants and 244 retransplants. The rates of positive B cell and T cell crossmatches were 10.1% and 7.4%, respectively, for primary transplants and 14.6% and 6.4%, respectively, for retransplants (P = 0.049 for a B cell crossmatch). Across all primary transplants, females (P < 0.001) and patients with autoimmune hepatitis (P < 0.001) had greater frequencies of positive crossmatches. There was no effect from race or age. For both primary transplants and retransplants, patient survival and graft survival were not affected by the presence of a positive crossmatch. With respect to posttransplant complications, there were no differences in rejection episodes (hyperacute, acute, or chronic) or technical complications (biliary and vascular) between negative and positive crossmatch groups. However, there were significant differences in the pathological findings of preservation injury (PI) on liver biopsy samples taken at the time of transplantation and within the first week of transplantation (P = 0.003 for B cells and P = 0.03 for T cells). In summary, a positive crossmatch had no significant impact on patient survival or graft outcomes. However, there was a significantly higher incidence of PI in primary LT recipients with a positive crossmatch. This finding is important for a broader understanding of PI, which may include a significant immunological component.

Hepatitis C recurrence is not adversely affected by the use of donation after cardiac death liver allografts

Many factors can worsen a recurrent hepatitis C virus (HCV) infection after liver transplantation (LT). We sought to determine whether the use of donation after cardiac death (DCD) livers affects HCV recurrence. From January 2000 to June 2008, 37 HCV patients underwent LT with DCD allografts. The outcomes and severity of HCV recurrence were analyzed along with those for 74 matched control patients with HCV who received donation after brain death (DBD) livers. The 2 groups had similar donor and recipient characteristics, immunosuppression regimens, rates of acute cellular rejection (ACR), and HCV profiles. DCD patients had a higher incidence of primary nonfunction (19% versus 3%, P = 0.006) and significantly higher peak aspartate aminotransferase levels in comparison with DBD subjects, suggesting a greater degree of ischemia/reperfusion injury. Although the survival rates were not significantly different, DCD recipients had lower 1- and 5-year patient survival rates (83% and 69% versus 84% and 78%, respectively, P = 0.75) and graft survival rates (70% and 61% versus 82% and 74%, respectively, P = 0.24). Three hundred fourteen protocol and clinically indicated liver biopsy procedures were performed within 6 years after transplantation, and mixed modeling analysis showed that fibrosis progression rates were similar for the 2 groups (0.6 fibrosis units/year according to the Ishak modified staging system). The rates of severe HCV recurrence (retransplantation or death due to recurrent hepatitis C and/or the development of stage 4/6 fibrosis or worse within 2 years) were similar [3 DCD patients (8%) versus 11 DBD patients (15%), P = 0.38], and cytomegalovirus infection (hazard ratio = 7.9, P = 0.002, 95% confidence interval = 2.1-28.9) and ACR (hazard ratio = 6.2, P = 0.002, 95% confidence interval = 2.0-19.7) were the only independent risk factors for severe recurrence. In summary, although there was a trend of poorer overall outcomes in DCD patients, the use of DCD livers did not appear to adversely affect HCV recurrence after LT.

Role of postreperfusion subcapsular wedge biopsies in predicting initially poor graft function after liver transplantation

Preservation injury is a major contributing factor to primary allograft failure or poor initial graft function after an orthotopic liver transplant (OLT). We examined the histopathological findings from postreperfusion wedge biopsy specimens in relation to early graft function during the first postoperative week among OLT patients at our center. We reanalyzed subcapsular postreperfusion biopsy specimens from 88 patients to histologically grade the lesions. Grafts were grouped as good function, initial poor function (an alanine aminotransferase or aspartate aminotransferase level >1500 IU/L during week 1), or primary nonfunction (death or retransplantation). Only 1 patient experienced primary nonfunction; the remaining patients fell into the other 2 groups: ie, good function or initial poor function. When patients were compared using numerous morphologic and clinical features, no statistical relation was observed regarding clinical data on bile duct complications, donor type, graft volume, patient age, or type of stent. Histological features of neutrophilic infiltration of the subcapsular region, hepatocellular ballooning, and macro/microvesicular steatosis were not related to initial poor graft function; in contrast, there were prominent sinusoidal neutrophilic infiltrations and hepatocellular necrosis. Preservation-reperfusion injury (grade 2 or grade 3 neutrophilic infiltration) occurred in 78.6% of initial poor function patients and in 39.7% of good function patients. Subcapsular neutrophilic infiltration, a sign of surgical hepatitis, did not provide prognostic information about graft survival. Similar to other studies, we observed neutrophilic infiltration and necrosis away from the capsule to predict subsequent graft function.

Secondary sclerosing cholangitis

Secondary sclerosing cholangitis (SSC) is a chronic cholestatic biliary disease, characterized by inflammation, obliterative fibrosis of the bile ducts, stricture formation and progressive destruction of the biliary tree that leads to biliary cirrhosis. SSC is thought to develop as a consequence of known injuries or secondary to pathological processes of the biliary tree. The most frequently described causes of SSC are longstanding biliary obstruction, surgical trauma to the bile duct and ischemic injury to the biliary tree in liver allografts. SSC may also follow intra-arterial chemotherapy. Sclerosing cholangitis in critically ill patients is a largely unrecognized new form of SSC, and is associated with rapid progression to liver cirrhosis. The mechanisms leading to cholangiopathy in critically ill patients are widely unknown; however, the available clinical data indicate that ischemic injury to the intrahepatic biliary tree may be one of the earliest events in the development of this severe form of sclerosing cholangitis. Therapeutic options for most forms of SSC are limited, and patients with SSC who do not undergo transplantation have significantly reduced survival compared with patients with primary sclerosing cholangitis. Sclerosing cholangitis in critically ill patients, in particular, is associated with rapid disease progression and poor outcome.

Management of biliary complications after orthotopic liver transplantation: The role of endoscopy

Biliary complications are significant causes of morbidity and mortality after orthotopic liver transplantation (OLT). The estimated incidence of biliary complications after OLT ranges between 10%-25%, however, these numbers continue to decline due to improvement in surgical techniques. The most common biliary complications are strictures (both anastomotic and non-anastomotic) and bile leaks. Most of these problems can be appropriately managed with endoscopic retrograde cholangiography (ERC). Other complications such as bile duct stones, bile casts, sphincter of Oddi dysfunction, and hemobilia, are less frequent and also can be managed with ERC. This article will review the risk factors, diagnosis, and endoscopic management of the most common biliary complications after OLT.

The ischemic preconditioning paradox in deceased donor liver transplantation-evidence from a prospective randomized single blind clinical trial

While animal studies show that ischemic preconditioning (IPC) is beneficial in liver transplantation (LT), evidence from few smaller clinical trials is conflicting. From October 2003 to July 2006, 101 deceased donors (DD) were randomized to 10 min IPC (n = 50) or No IPC (n = 51). Primary objective was efficacy of IPC to decrease reperfusion (RP) injury. Both groups had similar donor risk index (DRI) (1.54 vs. 1.57). Aminotransferases on days 1 and 2 were significantly greater (p < 0.05) in IPC recipients. In multivariate analyses, IPC had an independent effect only on day 2 aspartate transferase. Prothrombin time, bilirubin and histological injury were similar in both groups. IPC had no significant effect on plasma TNF-alpha, IL-6 and IL-10 in the donor and TNF-alpha and IL-6 in the recipient. In contrast, IPC recipients had a significant rise in systemic IL-10 levels after RP (p < 0.05) and had fewer moderate/severe rejections within 30 days (p = 0.09). Hospital stay was similar in both groups. One-year patient and graft survival in IPC versus No IPC were 88% versus 78% (p = 0.1) and 86 versus 76% (p = 0.25), respectively. IPC increases RP injury after DDLT, an 'IPC paradox'. Other potential benefits of IPC are limited. IPC may be more effective in combination with other preconditioning regimens.

Liver transplantation across Rh blood group barriers increases the risk of biliary complications

BACKGROUND

Cold ischemia time and the presence of postoperative hepatic arterial thrombosis have been associated with biliary complications (BC) after liver transplantation. An ABO-incompatible blood group has also been suggested as a factor for predisposal towards BC. However, the influence of Rh nonidentity has not been studied previously.

MATERIALS

Three hundred fifty six liver transplants were performed from 1995 to 2000 at our hospital. BC incidence and risk factors were studied in 345 patients.

RESULTS

Seventy patients (20%) presented BC after liver transplantation. Bile leakage (24/45%) and stenotic anastomosis (21/30%) were the most frequent complications. Presence of BC in Rh-nonidentical graft-host cases (23/76, 30%) was higher than in Rh-identical grafts (47/269, 17%) (P=0.01). BC was also more frequent in grafts with arterial thrombosis (9/25, 36% vs 60/319, 19%; P=0.03) and grafts with cold ischemia time longer than 430 min (26/174, 15% vs 44/171, 26%; P=0.01). Multivariate logistic regression confirmed that Rh graft-host nonidentical blood groups [RR=2(1.1-3.6); P=0.02], arterial thrombosis [RR=2.6(1.1-6.4); P=0.02] and cold ischemia time longer than 430 min [RR=1.8(1-3.2); P=0.02] were risk factors for presenting BC.

CONCLUSION

Liver transplantation using Rh graft-host nonidentical blood groups leads to a greater incidence of BC.

Preservation of steatotic livers: a comparison between cold storage and machine perfusion preservation

Liver grafts are frequently discarded due to steatosis. Steatotic livers can be classified as suboptimal and deteriorate rapidly during hypothermic static preservation, often resulting in graft nonfunction. Hypothermic machine perfusion (MP) has been introduced for preservation of donor livers instead of cold storage (CS), resulting in superior preservation outcomes. The aim of this study was to compare CS and MP for preservation of the steatotic donor rat liver. Liver steatosis was induced in male Wistar rats by a choline-methionine-deficient diet. After 24 hours hypothermic CS using the University of Wisconsin solution (UW) or MP using UW-Gluconate (UW-G), liver damage (liver enzymes, perfusate flow, and hyaluronic acid clearance) and liver function (bile production, ammonia clearance, urea production, oxygen consumption, adenosine triphosphate [ATP] levels) were assessed in an isolated perfused rat liver model. Furthermore, liver biopsies were visualized by hematoxylin and eosin staining. Animals developed 30 to 60% steatosis. Livers preserved by CS sustained significantly more damage as compared to MP. Bile production, ammonia clearance, urea production, oxygen consumption, and ATP levels were significantly higher after MP as compared to CS. These results were confirmed by histology. In conclusion, MP improves preservation results of the steatotic rat liver, as compared to CS.

Conventional versus piggyback technique of caval implantation; without extra-corporeal veno-venous bypass. A comparative study

Conventional orthotopic liver transplantation (CON-LT) involves resection of recipient cava, usually with extra-corporeal circulation (veno-venous bypass, VVB), while in the piggyback technique (PC-LT) the cava is preserved. Along with a temporary portacaval shunt (TPCS), better haemodynamic maintenance is purported with PC-LT. A prospective, consecutive series of 384 primary transplants (2000-2003) were analysed, 138 CON-LT (with VVB) and 246 PC-LT (54 without TPCS). Patient/donor characteristics were similar in the two groups. PC-LT required less usage of fresh-frozen plasma and platelets, intensive care stay, number of patients requiring ventilation after day 1 and total days spent on ventilator. The results were not different when comparing, total operating and warm ischaemia time (WIT), red cell usage, requirement for renal support, day 3 serum creatinine and total hospital stay. TPCS had no impact on outcome other than WIT (P = 0.02). Three patients in PC-LT group (three of 246;1.2%) developed caval outflow obstruction (P = 0.02). There was no difference in short- or long-term graft or patient survival. PC-LT has an advantage over CON-LT unsing VVB with respect to intraoperative blood product usage, postoperative ventilation requirement and ITU stay. VVB is no longer required and TPCS may be used selectively in adult transplantation.

Biliary complications after deceased-donor orthotopic liver transplantation

A wide range of potential biliary complications can occur after orthotopic liver transplantation (OLT). The most common biliary complications are bile leaks, anastomotic and intrahepatic strictures, stones, and ampullary dyfunction, which may occur in up to 20%-40% of OLT recipients. Leaks predominate in the early posttransplant period; stricture formation typically develops gradually over time. However, with the advent of new techniques, such as split-liver, reduced-size, and living-donor liver transplantation, the spectrum of biliary complications has changed. Risk factors for biliary complications comprise technical failure; T-tube or stent-related complications; hepatic artery thrombosis; bleeding; ischemia/reperfusion injury; and other immunological, nonimmunological, and infectious complications. Noninvasive diagnostic methods have been established and treatment modalities have been modified towards a primarily nonoperative, endoscopy-based strategy. Besides, the management of biliary complications after OLT requires a multidisciplinary approach, in which interventional and endoscopic treatment options have to be weighed up against surgical treatment options. The etiology and spectrum of bile duct complications, their diagnosis, and their treatment will be reviewed in this article.

Successful reuse of liver grafts after death of the first recipient

Brain death secondary to cerebrovascular disease is a possible early complication of orthotopic liver transplantation. If liver graft continues to function normally, the reuse of liver for another patient may be considered. We report three cases of successful reuse of liver grafts after death of the first recipient. In our experience, liver graft can be reused in the first weeks after a previous transplantation provided that liver function is good, in the absence of systemic uncontrolled infection, graft rejection and after gross graft examination at laparotomy.

Differentially Expressed Genes in Postperfusion Biopsies Predict Early Graft Dysfunction After Liver Transplantation

BACKGROUND

Preservation induced injury is a major contributing factor to early graft dysfunction in liver allograft recipients. We hypothesized that changes in gene expression represent the earliest indicator of ischemia/reperfusion-related injuries measurable in the graft and could be used as prognostic marker for the occurrence of graft-related complications.

METHODS

We studied the expression of 67 genes, known to play a role in acute inflammatory processes by real-time polymerase chain reaction in 59 postperfusion biopsies. The level of expression was correlated with the occurrence of graft-related complications.

RESULTS

We identified six genes that were significantly correlated with the occurrence of early graft dysfunction (Spearman test, two-tailed; P<0.05). High C-reactive protein (CRP) gene expression levels correlated significantly with the need of therapeutic interventions due to graft-related complications (P=0,011). Furthermore, five genes related to vascular endothelial cell physiology (CTGF, WWP2, CD274, VEGF. and its receptor FLT1) showed significantly reduced expression in the postperfusion biopsies of patients with need of therapeutic interventions due to graft-related complications in the first month (P<0.05). Using a risk score based on the expression of these five genes, complications could be predicted with 96% sensitivity (ROC analysis, specificity: 74%, positive predictive value: 72%, negative predictive value: 96%).

CONCLUSION

Quantitative gene expression analysis in postperfusion biopsies may be a valuable tool to prospectively identify patients at risk for early clinical allograft dysfunction after liver transplantation.

Cadaveric full-size liver transplantation and the graft alternatives in adults: a comparative study from a single centre

BACKGROUND/AIMS

This study aims to compare the results of living donor (LDLT), cadaveric split (SLT) and domino (DO) liver transplantation which are currently available alternatives to the conventional cadaveric full-size liver transplantation (CAD).

METHODS

Immunologic, vascular and biliary complications (BC) were evaluated in 38 LDLT, 20 SLT, 17 DO and 38 CAD recipients.

RESULTS

The incidence of acute rejection (AR) was similar between groups, and between blood-related and blood-unrelated patients. AR was more severe in the SLT group according to the Banff scores (P=0.03, P<0.001, P<0.001). The evolution of AR was similar between the groups, in terms of development of chronic rejection. No venous complications occurred in the overall population. The rate of arterial thrombosis (10.5, 10, 0 and 3%, respectively) was statistically similar between groups. The rate of BC (26, 40, 12, and 8%, respectively) was higher in the partial grafts than in the whole grafts (P=0.006), but was not significantly different within each group. There was an association between the severity of preservation injury and occurrence of AR (P=0.01) and arterial thrombosis (P=0.016), but not BC. One- and 2-year graft and patient survival rates were similar between groups.

CONCLUSIONS

None of the graft types seemed to confer immunological advantage. BC remained problematic in the partial grafts, independently from ischemia time.

Recurrent hepatitis C posttransplant: early preservation injury may predict poor outcome

Organ cold/warm ischemia is thought to be a risk factor for increased severity of recurrence of hepatitis C (HCV) post liver transplantation. We had noted some HCV patients with preservation injury (PI) to have particularly poor outcomes. Our goal was to determine if PI on biopsy in HCV patients is associated with earlier, more rapidly progressive recurrence or graft and patient survival. Sixty-nine patients from the University of Nebraska transplant database were included: 23 HCV patients with PI (group = 1), 23 non-HCV patients with PI (group = 2), and 23 HCV patients without PI (group = 3). Patient groups were matched for gender, age, immunosuppression, and time of transplantation for analysis. No difference in time to recurrence was noted between HCV groups (256 vs. 316 days posttransplant). More patients in group 1 had progression to stage 3 or 4 fibrosis, compared to group 3 (43 vs. 9%, P = 0.02). One-year survival for groups 1, 2, and 3 was 78, 82, and 100% respectively, whereas 3-yr survival was 59, 82, and 88% (group 1 vs. group 2 or 3 respectively, P = 0.0055). There was no difference in survival between groups 2 and 3. Patients in group 1 that received antiviral treatment had improved survival, compared to those who did not (P = 0.012). Risk factors for poor survival on univariate analysis included severity of PI (Relative Risk = 2.78, P < 0.001) and donor age of >55 (P = 0.014). Multivariate analysis shows HCV is the most important factor. In conclusion, HCV transplant patients with evidence of early PI on biopsy have poorer survival outcomes than non-HCV transplant patients with PI or HCV transplant patients without PI. Consideration for antiviral therapy early in the posttransplant course may be warranted in this subset of patients.

Bile duct complications after liver transplantation

Complications involving the biliary tract after orthotopic liver transplantation (OLT) have been a common problem since the early beginning of this technique. Biliary complications have been reported to occur at a relatively constant rate of approximately 10-15% of all deceased donor full size OLTs. There is a wide range of potential biliary complications which can occur after OLT. Their incidence varies according to the type of graft, type of donor, and the type of biliary anastomosis performed. The spectrum of biliary complications has changed over the past decade because of the establishment of split liver, reduced-size, and living donor liver transplantation. Apart from technical developments, novel diagnostic methods have been introduced and evaluated in OLT, the most prominent being magnetic resonance imaging (MRI). Treatment modalities have also changed over the past years towards a primarily nonoperative, endoscopy-based strategy, leaving the surgical intervention for lesions which otherwise are not curable. The management of biliary complications after OLT requires a multidisciplinary approach. Conservative, interventional, and endoscopic treatment options have to be weighed up against surgical re-intervention. In the following the spectrum of specific bile duct complications after OLT and their treatment options will be reviewed.

Update on post-liver transplantation infections, malignancies, and surgical complications

Complications of liver transplantation are not limited to acute and chronic rejection, and recurrence of original disease, but include surgical complications, most commonly hepatic artery occlusion, infections, and development of de novo malignancies. In the early posttransplantation period, procurement/preservation injury, non-immunologic injury to the graft during harvesting and implantation, is manifested by centrilobular hepatocyte pallor and cholestasis but rarely leads to significant graft dysfunction. Ischemic complications, such as hepatic artery thrombosis, are more serious complications and may lead to early graft loss or biliary stricture. Infectious complications generally occur in the mid-to-late period after transplantation; cytomegalovirus (CMV) remains a common pathogen. Human herpes 6 virus infection has been implicated in allograft dysfunction, but is usually seen in the setting of co-infection with CMV. De novo malignancies are emerging as a significant cause of mortality after liver transplantation; risk is cumulative, and increases with time posttransplantation. Development of such malignancies in the setting of solid organ transplantation is multifactorial, and is related to individual and regional predispositions to malignancy, pre-transplantation disease states, recipient viral status, and use and intensity of immunosuppression regimens.

Liver biopsy in evaluation of complications following liver transplantation

AIM: To analyze the role of liver biopsies in differential diagnosis after liver transplantation.

METHODS: A total of 50 biopsies from 27 patients with liver dysfunction out of 52 liver transplantation cases were included. Biopsies were obtained 0-330 d after operation, in which, 44 were fine needle biopsies, another 6 were wedge biopsies during surgery. All tissues were stained with haemotoxylin-eosin. Histochemical or immunohistochemical stain was done.

RESULTS: The rate of acute rejection in detected cases and total transplantation cases was 48.2% and 25.0%, chronic rejection rate in detected cases and total transplan-tation cases was 14.8% and 7.7%, preservation-reperfusion injury in detected cases and total transplantation cases was 25.9% and 13.5%, hepatic artery thrombosis rate in detected cases and total transplantation cases was 11.1% and 5.8%, intrahepatic biliary injury rate in detected cases and total transplantation cases was 7.4 % and 3.8%, CMV infection rate in detected cases and total transplantation cases was 3.7% and 1.9%, hepatitis B recurrence rate in detected cases and total transplantation cases was 3.7% and 1.9%, the ratio of suspicious drug-induced hepatic injury in detected cases and total transplantation cases was 11.1% and 5.8%.

CONCLUSION: Acute rejection and preservation-reperfusion injury are the major factors in early liver dysfunction after liver transplantation. Hepatic artery thrombosis and prolonged cold preservation may result in intrahepatic biliary injury. Acute rejection and viral infection may involve in the pathogenesis of chronic rejection. Since there are no specific lesions in drug-induced hepatic injury, the diagnosis must closely combine clinical history and rule out other possible complications.

Preservation injury patterns in liver transplantation associated with poor prognosis

Preservation injury (PI) is defined as hepatic dysfunction that occurs within 10 days of liver transplantation (OLT) but spontaneously resolves. However, we noted two new patterns: one characterized by histologic evidence of preservation injury that occurs at later than 10 days post-OLT (late PI), and a second, of persistent charge in liver biopsies > 10 days post-OLT (persistent PI). To characterize these new patterns, we performed a retrospective study of patients who underwent liver biopsies for hepatic dysfunction post-OLT from September 1993 to March 1998. The outcome of the 61 patients with preservation injury on liver biopsy after OLT was followed until the last clinic visit or death. Thirty patients had early PI, 16 patients had persistent preservation injury and 15 patients, late onset preservation injury. There were no significant differences in the age (P =.28), sex (P =.77), follow-up time (P =.78), cold ischemia (P =.3), or warm ischemia time (P =.16) between these groups. There was also no significant association between early preservation injury or persistent preservation injury with the development of acute or chronic rejection (P =.19). The overall survival rates at 1, 3, and 5 years was 52%, 45%, and 45%, respectively. There was no significant difference in survival between early, persistent, and late PI patterns (P =.59), although there was a trend toward better survival for patients with early preservation injury. The survival of OLT patients with persistent or late preservation injury is poor and should prompt consideration for retransplantation.

Diagnostic issues in liver transplantation pathology

Liver biopsy is used to determine the pathogenesis of liver dysfunction after liver transplantation. One or more causative factors may be identified on biopsy. The pathologist must be familiar with the histopathology of acute rejection to differentiate it from other potential complications, including biliary obstruction, intercurrent cytomegalovirus hepatitis, or recurrent disease. Consensus documents from the Banff international panel provide useful guidelines for the appropriate grading of acute and chronic rejection.