The Glasgow Prognostic Score and its variants predict mortality in living donor but not in deceased donor liver transplantation for hepatocellular carcinoma: A double-center validation study

AIM

This study aimed to evaluate whether the Glasgow Prognostic Score (GPS) and its variants are able to predict mortality in live donor and deceased donor liver transplantation for hepatocellular carcinoma.

METHODS

Data of 29 live donor and 319 deceased donor transplantations from two German transplant centers was analyzed. The GPS, modified GPS, hepatic GPS, and Abe score were investigated. Receiver operating characteristic (ROC) curve analysis was carried out to calculate the sensitivity, specificity, and overall model correctness of the investigated scores as a predictive model. Study end-points were 1-year, 3-year, and long-term mortality.

RESULTS

A 1-year mortality of 19.1% (n = 61), 3-year mortality of 26.3% (n = 84), and overall mortality of 37.3% (n = 119) was observed. All investigated scores failed to predict outcome in deceased donor liver transplantation (areas under ROC curves <0.700), whereas GPS, hepatic GPS, modified GPS, and the Abe score reached areas under ROC curves >0.700 for the prediction of 1-year mortality in live donor transplantation. The GPS and Abe score were also able to predict 3-year mortality. None of the investigated scores was a reliable predictor of long-term mortality.

CONCLUSION

Systemic inflammation-based scores have great prognostic potential in live donor transplantation. Abe score could be successfully externally validated in the current study for the first time. In deceased donor transplantation, none of the analyzed scores was able to allow reliable prediction for the investigated study end-points.

Identifying independent risk factors for graft loss after primary liver transplantation

PURPOSE

The aim of the study is the identification of independent risk factors for re-transplantation after primary liver transplantation beyond the occurrence of hepatic artery thrombosis.

METHODS

Eight hundred thirty-four adult patients undergoing primary liver transplantation were analyzed. A propensity score was developed using multivariable binary logistic regression with hepatic artery thrombosis as the dependent variable. The logit link function of the propensity score was included into multivariable Cox regression analysis for graft survival to adjust the study population.

RESULTS

Graft loss was observed in 134 patients (16.1%). Independent significant risk factors for graft loss were recipient platelet count (p = 0.040; HR: 1.002; 95%-CI: 1.000-1.003), preoperative portal vein thrombosis (p = 0.032; HR: 1.797; 95%-CI: 1.054-2.925), donor age (p < 0.001; HR: 1.026; 95%-CI: 1.012-1.040), percentage of macrovesicular steatosis of the graft (p = 0.011; HR: 1.037; 95%-CI: 1.009-1.061), early complications leading to revision surgery (p < 0.001; HR: 2.734; 95%-CI: 1.897-3.956), duration of the transplant procedure (p < 0.001; HR: 1.005; 95%-CI: 1.003-1.007) as well as transplantation of a split liver graft (p = 0.003; HR: 2.637; 95%-CI: 1.420-4.728). The logit of the propensity score did not reach statistical significance in the final multivariable Cox regression model (p = 0.111) indicating good adjustment for the occurrence of hepatic artery thrombosis.

CONCLUSION

Liver transplant programs might benefit from regular donor organ biopsies to assess the amount of macrovesicular steatosis. An elevated recipient platelet count can promote reperfusion injury leading to graft loss. A liver graft from an elderly donor should not be split or be transplanted in a recipient with detected portal vein thrombosis.

Hepatic encephalopathy before and neurological complications after liver transplantation have no impact on the employment status 1 year after transplantation

AIM

To investigate the impact of hepatic encephalopathy before orthotopic liver transplantation (OLT) and neurological complications after OLT on employment after OLT.

METHODS

One hundred and fourteen patients with chronic liver disease aged 18-60 years underwent neurological examination to identify neurological complications, neuropsychological tests comprising the PSE-Syndrome-Test yielding the psychometric hepatic encephalopathy score, the critical flicker frequency and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), completed a questionnaire concerning their occupation and filled in the short form 36 (SF-36) to assess health-related quality of life before OLT and 12 mo after OLT, if possible. Sixty-eight (59.6%) patients were recruited before OLT, while on the waiting list for OLT at Hannover Medical School [age: 48.7 ± 10.2 years, 45 (66.2%) male], and 46 (40.4%) patients were included directly after OLT.

RESULTS

Before OLT 43.0% of the patients were employed. The patients not employed before OLT were more often non-academics (employed: Academic/non-academic 16 (34.0%)/31 vs not employed 10 (17.6%)/52, P = 0.04), had more frequently a history of hepatic encephalopathy (HE) (yes/no; employed 15 (30.6%)/34 vs not employed 32 (49.2%)/33, P = 0.05) and achieved worse results in psychometric tests (RBANS sum score mean ± SD employed 472.1 ± 44.5 vs not employed 443.1 ± 56.7, P = 0.04) than those employed. Ten patients (18.2%), who were not employed before OLT, resumed work afterwards. The patients employed after OLT were younger [age median (range, min-max) employed 47 (42, 18-60) vs not employed 50 (31, 29-60), P = 0.01], achieved better results in the psychometric tests (RBANS sum score mean ± SD employed 490.7 ± 48.2 vs not employed 461.0 ± 54.5, P = 0.02) and had a higher health-related quality of life (SF 36 sum score mean ± SD employed 627.0 ± 138.1 vs not employed 433.7 ± 160.8; P < 0.001) compared to patients not employed after OLT. Employment before OLT (P < 0.001), age (P < 0.01) and SF-36 sum score 12 mo after OLT (P < 0.01) but not HE before OLT or neurological complications after OLT were independent predictors of the employment status after OLT.

CONCLUSION

HE before and neurological complications after OLT have no impact on the employment status 12 mo after OLT. Instead younger age and employment before OLT predict employment one year after OLT.

Identification of the resection severity index as a significant independent prognostic factor for early mortality and observed survival >5 and >10 years after liver resection for hepatocellular carcinoma

BACKGROUND AND OBJECTIVES

This study evaluates predictive factors for observed long-term survival of more than 5 and 10 years for patients after liver resection for hepatocellular carcinoma and compares their life expectancy to the normal national population matched for sex, year of birth and age at resection.

METHODS

230 patients after primary liver resection for HCC (01.01.1995-31.12.2004) were analyzed. Multivariable logistic regression models were determined based on Cox regression results and their prognostic capability evaluated with areas under the receiver operating characteristic curve (AUROCs).

RESULTS

Life years after surgery in deceased patients compared to the normal national population matched for sex, year of birth and age at resection was reduced by median 21.7 years. Independent predictive factors for 10-year survival were age at resection (p < 0.001; OR = 0.898; 95%-CI: 0.846-0.954), UICC 7 tumor staging (p = 0.003; OR = 0.344; 95%-CI: 0.126-0.941) and ASAT (GOT) in U/l divided by Quick in percent multiplied by the extent of liver resection graded in points labelled as the resection severity index (p < 0.001; OR = 0.136; 95%-CI: 0.022-0.843) enabling prediction of 10-year survival with an AUROC of 0.884. The same factors plus revision surgery (yes/no) predict 5-year survival (AUROC 0.736).

CONCLUSIONS

Liver resection enables predictable long-term survival >5 and > 10 years. The proposed resection severity index quantifies the prognostic relevance of liver cellular damage, synthesis and loss of parenchyma for long-term survival.

Inhibition of B-cell activation and antibody production by triggering inhibitory signals via the PD-1/PD-ligand pathway

BACKGROUND

The development of donor-reactive antibodies is regarded to be an important barrier limiting long-term outcome of allo- and xenografts. We asked whether enhanced signaling via the co-inhibitory receptor programmed cell death-1 (PD-1; CD279) can downregulate human B-cell activation.

METHODS

Proliferation of human purified CD19(+) B cells was induced by in vitro stimulation with CpG oligodeoxynucleotides (CpG-B). To induce antibody production, peripheral blood mononuclear cells were co-cultured with the porcine B-cell line L23. Triggering of inhibitory signals via the PD-1 receptor was obtained either using a recombinant agonistic soluble ligand (PD-L1.Ig) or L23 transfectants overexpressing membrane-bound human PD-L1 (CD274; L23-PD-L1 cells).

RESULTS

Stimulation of purified CD19(+) B cells with CpG-B resulted in upregulation of PD-1 and strong proliferation. Addition of PD-L1.Ig significantly reduced B-cell proliferation in a dose-dependent manner. A great proportion (~1%) of human circulating B cells recognizes the epitope galactose-α1,3-galactose-β1,4-N-acetylglucosamine-R (α-gal). Thus, when B cells-in the presence of T cell help-were cocultured with α-gal-expressing L23 cells, anti-gal and anti-L23 antibodies could readily be detected in the culture supernatant. The level of induced antibodies was significantly reduced when stimulation was performed by L23-PD-L1 cells.

CONCLUSIONS

Enhancing inhibitory signals may be part of future protocols to better control humoral immunity to allo- and xenografts.

Identification of patients at risk for renal impairment after living donor kidney transplantation

PURPOSE

Outcome after living donor kidney transplantation is highly relevant, since recipient and donor were exposed to notable harm. Reliable identification of risk factors is necessary.

METHODS

Three hundred sixty-six living donor kidney transplants were included in this observational retrospective study. Relevant risk factors for renal impairment 1 year after transplantation and delayed graft function were identified with univariable and multivariable binary logistic regression and ordinal regression analysis.

RESULTS

Eighty-four patients (26.6 %) suffered from renal impairment KDIGO stage ≥4 1 year post-transplant; median estimated glomerular filtration rate was 35.3 ml/min. In multivariable ordinal regression, male recipient sex (p < 0.001), recipient body mass index (p = 0.006), donor age (p = 0.002) and high percentages of panel reactive antibodies (p = 0.021) were revealed as independent risk factors for higher KDIGO stages. After adjustment for post-transplant data, recipient male sex (p < 0.001), donor age (p = 0.026) and decreased early renal function at the first post-transplant outpatient visit (p < 0.001) were identified as independent risk factors. Delayed graft function was independently associated with long stay on the waiting list (p = 0.011), high donor body mass index (p = 0.043), prolonged warm ischemic time (p = 0.016) and the presence of preformed donor-specific antibodies (p = 0.043).

CONCLUSIONS

Broadening the donor pool with non-blood related donors seems to be legitimate, although with respect to careful medical selection, since donor age in combination with male recipient sex were shown to be risk factors for decreased graft function. Warm ischemic time and waiting time need to be kept as short as possible to avoid delayed graft function. Transplantation across HLA and ABO borders did not affect outcome significantly.

Independent Pre-Transplant Recipient Cancer Risk Factors after Kidney Transplantation and the Utility of G-Chart Analysis for Clinical Process Control

Background

The aim of this study is to identify independent pre-transplant cancer risk factors after kidney transplantation and to assess the utility of G-chart analysis for clinical process control. This may contribute to the improvement of cancer surveillance processes in individual transplant centers.

Patients and Methods

1655 patients after kidney transplantation at our institution with a total of 9,425 person-years of follow-up were compared retrospectively to the general German population using site-specific standardized-incidence-ratios (SIRs) of observed malignancies. Risk-adjusted multivariable Cox regression was used to identify independent pre-transplant cancer risk factors. G-chart analysis was applied to determine relevant differences in the frequency of cancer occurrences.

Results

Cancer incidence rates were almost three times higher as compared to the matched general population (SIR = 2.75; 95%-CI: 2.33–3.21). Significantly increased SIRs were observed for renal cell carcinoma (SIR = 22.46), post-transplant lymphoproliferative disorder (SIR = 8.36), prostate cancer (SIR = 2.22), bladder cancer (SIR = 3.24), thyroid cancer (SIR = 10.13) and melanoma (SIR = 3.08). Independent pre-transplant risk factors for cancer-free survival were age <52.3 years (p = 0.007, Hazard ratio (HR): 0.82), age >62.6 years (p = 0.001, HR: 1.29), polycystic kidney disease other than autosomal dominant polycystic kidney disease (ADPKD) (p = 0.001, HR: 0.68), high body mass index in kg/m² (p<0.001, HR: 1.04), ADPKD (p = 0.008, HR: 1.26) and diabetic nephropathy (p = 0.004, HR = 1.51). G-chart analysis identified relevant changes in the detection rates of cancer during aftercare with no significant relation to identified risk factors for cancer-free survival (p<0.05).

Conclusions

Risk-adapted cancer surveillance combined with prospective G-chart analysis likely improves cancer surveillance schemes by adapting processes to identified risk factors and by using G-chart alarm signals to trigger Kaizen events and audits for root-cause analysis of relevant detection rate changes. Further, comparative G-chart analysis would enable benchmarking of cancer surveillance processes between centers.

The new liver allocation score for transplantation is validated and improved transplant survival benefit in Germany but not in the United Kingdom

Prognostic models for the prediction of 90-day mortality after transplantation with pretransplant donor and recipient variables are needed to calculate transplant benefit. Transplants in adult recipients in Germany (Hannover, n = 770; Kiel, n = 234) and the United Kingdom (Birmingham, n = 829) were used for prognostic model design and validation in separate training and validation cohorts. The survival benefit of transplantation was estimated by subtracting the observed posttransplant 90-day mortality from the expected 90-day mortality without transplantation determined by the Model for End-Stage Liver Disease (MELD) score. A prognostic model called the liver allocation score (LivAS) was derived using a randomized sample from Hannover using pretransplant donor and recipient variables. This model could be validated in the German training and validation cohorts (area under the receiver operating characteristic curve [AUROC] > 0.70) but not in the English cohort (AUROC, 0.58). Although 90-day mortality rates after transplantation were 13.7% in Hannover, 12.1% in Kiel, and 8.3% in Birmingham, the calculated 90-day survival benefits of transplantation were 6.8% in Hannover, 7.8% in Kiel, and 2.8% in Birmingham. Deployment of the LivAS for limiting allocation to donor and recipient combinations with likely 90-day survival as indicated by pretransplant LivAS values below the cutoff value would have increased the survival benefit to 12.9% in the German cohorts, whereas this would have decreased the benefit in England to 1.3%. The English and German cohorts revealed significant differences in 21 of 28 pretransplant variables. In conclusion, the LivAS could be validated in Germany and may improve German allocation policies leading to greater survival benefits, whereas validation failed in England due to profound differences in the selection criteria for liver transplantation. This study suggests the need for national prognostic models. Even though the German centers had higher rates of 90-day mortality, estimated survival benefits were greater. Liver Transplantation 22 743-756 2016 AASLD.

Cholangitis in the postoperative course after biliodigestive anastomosis

BACKGROUND

Hepatobiliary surgery with biliodigestive anastomosis (BDA) results in a loss of the sphincter of Oddi with consecutive ascension of bacteria into the bile system which may cause cholangitis in the postoperative course.

METHODS

Patients who received reconstruction with a BDA after hepatobiliary surgery were analyzed retrospectively for their postoperative course of disease depending on intraoperatively obtained bile cultures and antibiotic prophylaxis.

RESULTS

Two hundred forty-three patients were included in the analysis, 49.4 % of whom had received endoscopic stenting before the operation. Stenting was significantly associated with the presence of drug-resistant bacteria in the intraoperatively obtained bile sample (p < 0.001, OR = 4.09). Of all patients, 14.4 % developed postoperative cholangitis. This was significantly associated with the postoperative length of stay in the intensive care unit (p = 0.002, OR = 1.035). The highest incidence of postoperative cholangitis was found in patients with cholangiocellular carcinoma (n = 12, p = 0.046, OR = 2.178). Patients were more likely to harbor strains with resistance against the antibiotic that was given intraoperatively.

CONCLUSION

The risk for the presence of drug-resistant bacteria is increased by preoperative stenting of the common bile duct. Bile culture by intraoperative swabs can be altered by the perioperative antibiotic prophylaxis as it induces microbiological selection in the common bile duct.

Efficacy and safety of sofosbuvir/ledipasvir for the treatment of patients with hepatitis C virus re-infection after liver transplantation

BACKGROUND

Hepatitis C virus (HCV) infection is associated with a particularly poor outcome after liver transplantation. In December 2014, sofosbuvir/ledipasvir (SOF/LDV) fixed-dose combination (FDC) was approved for HCV genotype 1 and 4 in Europe. In orthotopic liver transplantation (OLT) recipients, the interferon-free treatment of HCV re-infection with novel direct-acting antivirals has been demonstrated to be safe and effective in clinical trials, but real-world data are missing. The aim of this study was to investigate the safety and efficacy of SOF/LDV FDC in OLT recipients in the real-life setting.

METHODS

All consecutive OLT patients started on SOF/LDV FDC for 12 or 24 weeks at the University Medical Center Hamburg-Eppendorf and Medical School Hannover between October 2014 and August 2015 were retrospectively analyzed (n = 30). The primary efficacy endpoint was sustained virological response (SVR), i.e., absence of viremia 12 weeks after end of treatment (SVR 12). Liver function tests, creatinine, blood count, and HCV RNA (by polymerase chain reaction assay) were determined at each visit.

RESULTS

SVR was achieved in 29/30 patients (96.67%) treated with SOF/LDV ± ribavirin (RBV) for 12 (n = 4) or 24 weeks (n = 25). Twenty-five patients (86.2%) received RBV. However, in 15 of the 25 patients, RBV administration had to be discontinued because of severe anemia (57.7%). One RBV-treated patient died of a myocardial infarction during antiviral therapy; this event was most likely not directly related to SOF/LDV. Aside from RBV-associated anemia, no severe side effects of the antiviral regimen were observed.

CONCLUSION

Antiviral treatment with SOF/LDV is highly effective, safe, and well tolerated in OLT recipients. The addition of RBV often results in severe anemia, requiring dose reduction or discontinuation.

Effect of TNF-alpha blockade on coagulopathy and endothelial cell activation in xenoperfused porcine kidneys

BACKGROUND

Following pig-to-primate kidney transplantation, endothelial cell activation and xenogenic activation of the recipient's coagulation eventually leading to organ dysfunction and microthrombosis can be observed. In this study, we examined the effect of a TNF-receptor fusion protein (TNF-RFP) on endothelial cell activation and coagulopathy utilizing an appropriate ex vivo perfusion system.

METHODS

Using an ex vivo perfusion circuit based on C1-Inhibitor (C1-Inh) and low-dose heparin administration, we have analyzed consumptive coagulopathy following contact of human blood with porcine endothelium. Porcine kidneys were recovered following in situ cold perfusion with Histidine-tryptophan-ketoglutarate (HTK) organ preservation solution and were immediately connected to a perfusion circuit utilizing freshly drawn pooled porcine or human AB blood. The experiments were performed in three individual groups: autologous perfusion (n = 5), xenogenic perfusion without any further pharmacological intervention (n = 10), or with addition of TNF-RFP (n = 5). After perfusion, tissue samples were obtained for real-time PCR and immunohistological analyses. Endothelial cell activation was assessed by measuring the expression levels of E-selectin, ICAM-1, and VCAM-1.

RESULTS

Kidney survival during organ perfusion with human blood, C1-Inh, and heparin, but without any further pharmacological intervention was 126 ± 78 min. Coagulopathy was observed with significantly elevated concentrations of D-dimer and thrombin-antithrombin complex (TAT), resulting in the formation of multiple microthrombi. Endothelial cell activation was pronounced, as shown by increased expression of E-selectin and VCAM-1. In contrast, pharmacological intervention with TNF-RFP prolonged organ survival to 240 ± 0 min (max. perfusion time; no difference to autologous control). Formation of microthrombi was slightly reduced, although not significantly, if compared to the xenogenic control. D-dimer and TAT were elevated at similar levels to the xenogenic control experiments. In contrast, endothelial cell activation, as shown by real-time PCR, was significantly reduced in the TNF-RFP group.

CONCLUSION

We conclude that although coagulopathy was not affected, TNF-RFP is able to suppress inflammation occurring after xenoperfusion in this ex vivo perfusion model.

A Depleting Anti-CD45 Monoclonal Antibody as Isolated Conditioning for Bone Marrow Transplantation in the Rat

Objective

A monoclonal antibody (mAb) against the leukocyte common antigen CD45 (RT7 in rats) could facilitate bone marrow transplantation (BMT). This study in rats evaluates a depletive rat anti-RT7^a mAb as isolated tool for BMT conditioning without using irradiation or any chemotherapeutic / immunosuppressive agent.

Methods

The model used a CD45 di-allelic polymorphism (RT7^a/RT7^b). The anti-RT7^a mAb was intravenously administered to LEW.1W rats (RT1^uRT7^a) at 5, 10 and 15 mg/kg. 1x10⁸ BM cells of MHC syngeneic (RT1^u), MHC disparate (RT1^l) or MHC haploidentical (RT1^u/l) donors were transplanted. All BM donor strains carried the RT7^b allele so that their CD45⁺ cells were not affected by the anti-RT7^a mAb. Recipients were monitored for reconstitution and donor-chimerism in blood leukocytes.

Results

mAb dosages of 5 or 10 mg/kg were myelosuppressive, whereas 15 mg/kg was myeloablative. Multi-lineage donor-chimerism at day 100 indicated engraftment of MHC syngeneic BM after any used mAb dosage (5 mg/kg: 46+/-7%; 10 mg/kg: 62+/-5%; 15 mg/kg: 80+/-4%). MHC disparate BM resulted in autologous reconstitution after conditioning by 10 mg/kg of the mAb and caused transient chimerism ending up in death associated with aplasia after conditioning by 15 mg/kg of the mAb. MHC haploidentical BM (F1 to parental) engrafted only after conditioning by 15 mg/kg (chimerism at day 100: 78+/-7%). Abandonment of α/β TCR⁺ cell depletion from BM grafts impaired the engraftment process after conditioning using 15 mg/kg of the mAb in the MHC syngeneic setting (2 of 6 recipients failed to engraft) and the MHC haploidentical setting (3 of 6 recipients failed).

Conclusion

This depletive anti-RT7^a mAb is myelosuppressive and conditions for engraftment of MHC syngeneic BM. The mAb also facilitates engraftment of MHC haploidentical BM, if a myeloablative dose is used. RT7^b expressing, BM-seeded α/β TCR⁺ cells seem to impair the engraftment process after myeloablative mAb conditioning.

Liver transplantation for adenomatosis: European experience

The aim of this study was to collect data from patients who underwent liver transplantation (LT) for adenomatosis; to analyze the symptoms, the characteristics of the disease, and the recipient outcomes; and to better define the role of LT in this rare indication. This retrospective multicenter study, based on data from the European Liver Transplant Registry, encompassed patients who underwent LT for adenomatosis between January 1, 1986, and July 15, 2013, in Europe. Patients with glycogen storage disease (GSD) type IA were not excluded. This study included 49 patients. Sixteen patients had GSD, and 7 had liver vascular abnormalities. The main indications for transplantation were either a suspicion of hepatocellular carcinoma (HCC; 15 patients) or a histologically proven HCC (16 patients), but only 17 had actual malignant transformation (MT) of adenomas. GSD status was similar for the 2 groups, except for age and the presence of HCC on explants (P = 0.030). Three patients with HCC on explant developed recurrence after transplantation. We obtained and studied the pathomolecular characteristics for 23 patients. In conclusion, LT should remain an extremely rare treatment for adenomatosis. Indications for transplantation primarily concern the MT of adenomas. The decision should rely on morphological data and histological evidence of MT. Additional indications should be discussed on a case-by-case basis. In this report, we propose a simplified approach to this decision-making process.

Liver Resection for Non-Colorectal Liver Metastases - Standards and Extended Indications

Background

Due to the uncertain benefit of liver resection for non-colorectal liver metastases (NCLM), patient selection for surgery is generally difficult. Therefore, the aim of this article was to propose standard and extended indications for liver resection in this heterogeneous disease collective.

Methods

Review of the literature.

Results

The myriad of biologically different primary tumor entities as well as the mostly small and retrospective studies investigating the benefit of surgery for NCLM limits the proposal of general recommendations. Only resection of neuroendocrine liver metastases (NELM) appears to offer a clear benefit with a 5- and 10-year overall survival (OS) of 74 and 51%, respectively, in the largest series. Resection of liver metastases from genitourinary primaries might offer reasonable benefit in selected cases – with a 5-year OS of up to 61% for breast cancer and of 38% for renal cell cancer. The long-term outcome following surgery for other entities was remarkably poorer, e.g., gastric cancer, pancreatic cancer, and melanoma reached a 5-year OS of 20-42, 17-25, and about 20%, respectively.

Conclusion

Liver resection for NELM can be defined as a standard indication for the resection of NCLM while lesions of genitourinary origin might be defined as an extended indication.

Post-Operative Hemorrhage After Liver Transplantation: Risk Factors and Long-Term Outcome

BACKGROUND

Increasing scarcity of donated liver grafts clearly demonstrates the desperate need for ongoing outcome analysis to improve patient and graft survival after liver transplantation. Coagulation is often severely deteriorated in patients suffering from liver disease, thus leading to bleeding complications after liver transplantation.

MATERIAL AND METHODS

We included 770 liver transplantations in this single-center retrospective analysis to identify independent risk factors for post-operative hemorrhage. The relevance of bleeding complications was assessed with special regards to coagulation-related variables. Multivariate regression analyses allowed weighing of different risk factors.

RESULTS

Post-operative hemorrhage leading to revision surgery was observed in 19.9% (n=153 cases) of cases and was revealed as an independent risk factor for mortality (p=0.014; HR: 1.457; 95%-CI: 1.081-1.964). Risk-adjusted multivariate regression analysis compiling all pre- and intra-operative donor and recipient variables revealed that only the number of transfused packed red blood cells (p<0.001; OR: 1.072; 95%-CI: 1.036-1.110), hepatitis B virus-related liver disease (p=0.019; OR: 0.082; 95%-CI: 0.010-0.666), model of end-stage liver disease-era (p=0.020; OR: 1.016; 95%-CI: 1.002-1.029), partial thromboplastin time at transplantation (p=0.021; OR: 1.016; 95%-CI: 1.002-1.029), and donor intensive care unit stay in days (p=0.009; OR: 1.009; 95%-CI: 1.002-1.016) were significantly associated with the occurrence of post-operative hemorrhage.

CONCLUSIONS

Post-operative hemorrhage relevantly contributed post-transplant mortality. Avoidance of excessive packed red blood cell use during transplantation and short donor-intensive care unit stay lead to a decreased rate of bleeding complications. Coagulations state at transplantation is also relevant for favorable outcome.

Impairment of the Peritoneal Surface as a Decisive Factor for Intestinal Adhesions in Intraperitoneal Onlay Mesh Surgery - Introducing a New Rat Model

BACKGROUND

Meshes implanted intraperitoneally are known to cause adhesions potentially resulting in complications such as chronic pain, enterocutaneous fistula, or mesh infection. This study introduces a model for investigation of intestine-to-mesh adhesions and evaluates as to whether missing of visceral peritoneum is causative.

METHODS

In 18 rats, rectangular 1.5 x 2 cm patches of an uncoated polypropylene mesh (Ultrapro(®)) were sewn to the inner abdominal wall next to the cecum. Additionally, a meso-suture ensured contact between cecum and mesh. Rats were assigned to 2 groups: in 8 rats the peritoneum was left intact, in 10 the cecum was depleted from peritoneum with abrasion. Sacrifice was on day 7. Macroscopic evaluation used two adhesion scores. Specimens were evaluated microscopically, statistical analyses employed student's t-test.

RESULTS

On day 7, rats with mesh implantation combined with locally de-peritonealization by cecal abrasion mostly showed severe cecum-to-mesh agglutination (mean Lauder score 92%, mean total Hoffmann score 90%), whereas meshes of most animals without cecal abrasion only had some coverage with intraabdominal fat (33%, 24%; p = 0.0002). Histological work-up showed adequate wall ingrowth of mesh in all rats. In animals with cecal abrasion, meshes were mostly adhesive with cecal wall. However, when the peritoneum of cecum was unimpaired, abdominal wall above the mesh as well as cecum usually revealed sub-peritoneal tissue and a mono-layer cell coverage as seen in normal peritoneum.

CONCLUSION

This study introduces a model mimicking a clinical situation of e.g. hernia repair by intraperitoneally implanted meshes when mesh has contact with normal and with de-peritonealized intestine. The model might be useful for testing mesh types and coatings as well as other devices for their efficacy in adhesion prevention. The high adhesion scores of rats with local de-peritonealization compared with the low scores of animals with intact peritoneum indicate that the integrity of intestinal peritoneum is a decisive factor for adhesion formation.

Evaluation of the Effectiveness of Peritoneal Adhesion Prevention Devices in a Rat Model

BACKGROUND

Abdominal operations are followed by adhesions, a prevalent cause of abdominal pain, and the most frequent cause for bowel obstruction and secondary female infertility. This rat study addresses adhesion prevention capability of Adept(®), Interceed(®), Seprafilm(®), and a novel device, 4DryField(®) PH which is provided as powder and generates its effect as gel.

METHODS

Sixty-eight male Lewis rats had cecal abrasion and creation of an equally sized abdominal wall defect, and were grouped randomly: A control group without treatment (n=10); two groups treated with 4DryField(®) PH using premixed gel (n=15) or in-situ gel technique (n=16); one group each was treated with Seprafilm(®) (n=8), Interceed(®) (n=9), or Adept(®) (n=10). Sacrifice was on day 7 to evaluate incidence, quality, and quantity of adhesions, as expressed via adhesion reduction rate (AR). Histologic specimens were evaluated. Statistical analyses used ANOVA and unpaired t-tests.

RESULTS

4DryField(®) PH significantly reduced incidence and severity of adhesions both as premixed gel (AR: 85.2%) and as in-situ made gel (AR: 100%), a comparison between these two application techniques showed no differences in efficacy. Seprafilm(®) did not reduce incidence but severity of adhesions significantly (AR: 53.5%). With Interceed(®) (AR: 3.7%) and Adept(®) (AR: 16.1%) no significant adhesion-reduction was achieved. Except for inflammatory response with Interceed(®), histopathology showed good tissue compatibility of all other devices.

CONCLUSION

4DryField(®) PH and Seprafilm(®) showed significant adhesion prevention capabilities. 4DryField(®) PH achieved the highest adhesion prevention effectiveness without restrictions concerning mode of application and compatibility and, thus, is a promising strategy to prevent abdominal adhesions.

Prediction of survival and tumor recurrence in patients undergoing surgery for pancreatic neuroendocrine neoplasms

BACKGROUND

This study strives to define prognostic models for outcome after surgery for malignant pancreatic neuroendocrine tumors.

METHODS

Forty-one patients were included. Prognostic models for mortality and disease recurrence were developed with multivariate binary logistic regression.

RESULTS

The proposed prognostic model for tumor recurrence risk after surgery in percentage (AUROC = 0.774, 95%CI = 0.611-0.937) is: Risk in % = Exp(Y)/(1 + Exp(Y)), with Y = -4.360 + (0.015 × tumor diameter in cm) + (0.010 × preoperative platelet count in thousand/μl) + (1.077 × distant metastases, if yes = 1; if no = 0) + (-0.026 × Ki-67-positive cells in %) + (-1.086 × upper abdominal pain, if yes = 1; if no = 0). The proposed prognostic model for observed 3-year survival probability after surgery in % (AUROC = 0.932, 95%CI = 0.857-0.999) is: Survival probability in % = Exp(Y)/(1 + Exp(Y)), with Y = -12.492 + (0.054 × preoperative platelet count in thousand/μl) + (0.112 × minimal distance of the resection margin from the tumor in mm) + (-1.574 × number of positive lymph nodes) + (2.292 × histological tumor infiltration, if yes = 1; if no = 0) CONCLUSIONS: The platelet count was identified as a relevant risk factor. Proposed prognostic models with good model-fit display properties that indicate potential clinical usefulness.

[Transplant Surgeon Meets Nephrologist: Important Nephrological Aspects Before and After Kidney or Liver Transplantation]

In cases of chronic renal insufficiency, successful kidney transplantation is the method of choice to restore patients' health, well-being and physical fitness. The interdisciplinary collaboration of nephrologists and transplant surgeons has always been a prerequisite for the successful pre-, peri- and post-transplant care of renal transplant patients. The same holds true for liver transplant patients. Here the nephrologist is often involved in cases requiring pre- or post-transplant dialysis as well as in decision making for combined liver-kidney transplantation. This review focuses on nephrological aspects in patient care before and after kidney and liver transplantation.

The c.503T>C Polymorphism in the Human KLRB1 Gene Alters Ligand Binding and Inhibitory Potential of CD161 Molecules

Studying genetic diversity of immunologically relevant molecules can improve our knowledge on their functional spectrum in normal immune responses and may also uncover a possible role of different variants in diseases. We characterized the c.503T>C polymorphism in the human KLRB1 gene (Killer cell lectin-like receptor, subfamily B, member 1) coding for the cell surface receptor CD161. CD161 is expressed by subsets of CD4⁺ and CD8⁺ T cells and the great majority of CD56⁺ natural killer (NK) cells, acting as inhibitory receptor in the latter population. Genotyping a cohort of 118 healthy individuals revealed 40% TT homozygotes, 46% TC heterozygotes, and 14% carriers of CC. There was no difference in the frequency of CD161 expressing CD4⁺ and CD8⁺ T cells between the different genotypes. However, the frequency of CD161⁺ NK cells was significantly decreased in CC carriers as compared to TT homozygotes. c.503T>C causes an amino acid exchange (p.Ile168Thr) in an extracellular loop of the CD161 receptor, which is regarded to be involved in binding of its ligand Lectin-like transcript 1 (LLT1). Binding studies using soluble LLT1-Fc on 293 transfectants over-expressing CD161 receptors from TT or CC carriers suggested diminished binding to the CC variant. Furthermore, triggering of CD161 either by LLT1 or anti-CD161 antibodies inhibited NK cell activation less effectively in cells from CC individuals than cells from TT carriers. These data suggest that the c.503T>C polymorphism is associated with structural alterations of the CD161 receptor. The regulation of NK cell homeostasis and activation apparently differs between carriers of the CC and TT variant of CD161.

Model of End-Stage Liver Disease Score and Derived Variants Lack Prognostic Ability after Liver Transplantation

BACKGROUND The model of end-stage liver disease (MELD) score is currently used for donor liver allocation in many regions. The objective of this retrospective study was to assess the MELD score and its diverse variants as prognostic models for mortality after liver transplantation. MATERIAL AND METHODS An analysis of 454 consecutive adult liver transplants since the introduction of MELD-based donor liver allocation was conducted. Eight different MELD score variants were investigated. Receiver operating characteristic (ROC) curve analysis was performed to calculate the sensitivity, specificity, and overall model correctness of the investigated scores as a predictive model. The Brier score was used for the prediction of model accuracy and calculated as described before. Study endpoints were 90-day mortality and long-term patient mortality. RESULTS A 90-day mortality of 15.4% (n=69) and long-term mortality of 25% (n=112) were observed. All investigated models fail to reach relevant areas under the ROC curve greater than 0.700 for the prediction of mortality after liver transplantation. All calculated Brier scores were greater than 0.25, indicating a significant lack of model discrimination and calibration of the investigated scores. CONCLUSIONS A prognostic model for the prediction of outcome after transplantation still needs to be identified and should allow weighing urgency against utility in liver transplantation.

Long-term outcome of liver transplant patients with Budd-Chiari syndrome secondary to myeloproliferative neoplasms

BACKGROUND

A considerable proportion of patients receiving liver transplants for Budd-Chiari syndrome (BCS) suffer from myeloproliferative neoplasms (MPN). This study evaluated the long-term prognosis of liver-transplanted patients with BCS secondary to MPN and the effect of immunosuppression on MPN progression.

METHODS

A total of 78 patients with BCS were evaluated between 1982 and 2013. Of those, 40 patients suffered from polycythaemia vera (PV) and essential thrombocythaemia (ET). One patient had primary myelofibrosis (PMF). All patients received the standard immunosuppressive regimen. We retrospectively evaluated the long-term survival, clinical course and laboratory parameters of patients with MPN.

RESULTS

Exactly 29/41 patients (71%) with MPN survived ≥ 3 years [mean age 36 ± 11 years; females n = 27 (93%)]. Mean follow-up after orthotopic liver transplantation (OLT) was 12.4 ± 7.3 years (range 3-28 years). Five- and 10-year survival rates were not significantly different in patients with and without MPN (P = 0.81 and P = 0.66 respectively) or in patients with PV and ET (P = 0.29 and P = 0.55 respectively). Thrombosis and bleeding developed in 7/29 (24%) long-term MPN survivors with no significant difference between ET and PV (P = 0.18). In the long-term follow-up, there was no evidence of progression to overt myelofibrosis or acute myeloid leukaemia (AML). In the uni- and multivariate Cox-regression analyses, MPN did not influence survival after OLT.

CONCLUSIONS

Budd-Chiari syndrome patients with and without underlying MPN had similar long-term survival rates after OLT. There was no evidence of enhanced progression of MPN after OLT secondary to immunosuppressive therapy. However, major haemorrhage and recurrent thrombosis contributed to morbidity and mortality after OLT in those patients.

Long-term results after adult ex situ split liver transplantation since its introduction in 1987

BACKGROUND

Split liver transplantation is still discussed controversially. Utilization of split liver grafts has been declining since a change of allocation rules for the second graft abolished incentives for German centres to perform ex situ splits. We therefore analysed our long-term experiences with the first ex situ split liver transplant series worldwide.

METHODS

A total of 131 consecutive adult ex situ split liver transplants (01.12.1987-31.12.2010) were analysed retrospectively.

RESULTS

Thirty-day mortality rates and 1- and 3-year patient survival rates were 13, 76.3, and 66.4 %, respectively. One- and three-year graft survival rates were 63.4 and 54.2 %, respectively. The observed 10-year survival rate was 40.6 %. Continuous improvement of survival from era 1 to 3 was observed (each era: 8 years), indicating a learning curve over 24 years of experience. Patient and graft survival were not influenced by different combinations of transplanted segments or types of biliary reconstruction (p > 0.05; Cox regression). Patients transplanted for primary sclerosing cholangitis had better survival (p = 0.021; log-rank), whereas all other indications including acute liver failure (13.6 %), acute and chronic graft failure (9.1 %) had no significant influence on survival (p > 0.05; log-rank). Biliary complications (27.4 %) had no significant influence on patient or graft survival (p > 0.05; log-rank). Hepatic artery thrombosis (13.2 %) had a significant influence on graft survival but not on patient survival (p = 0.002, >0.05, respectively; log-rank).

CONCLUSIONS

Split liver transplantation can be used safely and appears to be an underutilized resource that may benefit from liberal allocation of the second graft.

Renal Function in De Novo Liver Transplant Recipients Receiving Different Prolonged-Release Tacrolimus Regimens-The DIAMOND Study

DIAMOND: multicenter, 24-week, randomized trial investigating the effect of different once-daily, prolonged-release tacrolimus dosing regimens on renal function after de novo liver transplantation. Arm 1: prolonged-release tacrolimus (initial dose 0.2mg/kg/day); Arm 2: prolonged-release tacrolimus (0.15-0.175mg/kg/day) plus basiliximab; Arm 3: prolonged-release tacrolimus (0.2mg/kg/day delayed until Day 5) plus basiliximab. All patients received MMF plus a bolus of corticosteroid (no maintenance steroids).

PRIMARY ENDPOINT

eGFR (MDRD4) at Week 24. Secondary endpoints: composite efficacy failure, BCAR and AEs. Baseline characteristics were comparable. Tacrolimus trough levels were readily achieved posttransplant; initially lower in Arm 2 versus 1 with delayed initiation in Arm 3. eGFR (MDRD4) was higher in Arms 2 and 3 versus 1 (p = 0.001, p = 0.047). Kaplan-Meier estimates of composite efficacy failure-free survival were 72.0%, 77.6%, 73.9% in Arms 1-3. BCAR incidence was significantly lower in Arm 2 versus 1 and 3 (p = 0.016, p = 0.039). AEs were comparable. Prolonged-release tacrolimus (0.15-0.175mg/kg/day) immediately posttransplant plus basiliximab and MMF (without maintenance corticosteroids) was associated with lower tacrolimus exposure, and significantly reduced renal function impairment and BCAR incidence versus prolonged-release tacrolimus (0.2mg/kg/day) administered immediately posttransplant. Delayed higher-dose prolonged-release tacrolimus initiation significantly reduced renal function impairment compared with immediate posttransplant administration, but BCAR incidence was comparable.