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Featured researches published by Jürgen Klempnauer.


Journal of Hepatology | 2012

Evolution of indications and results of liver transplantation in Europe. A report from the European Liver Transplant Registry (ELTR).

René Adam; Vincent Karam; V. Delvart; John O’Grady; Darius F. Mirza; Jürgen Klempnauer; Denis Castaing; Peter Neuhaus; Neville V. Jamieson; Mauro Salizzoni; S. Pollard; Jan Lerut; Andreas Paul; Juan Carlos García-Valdecasas; Fernando San Juan Rodríguez; Andrew K. Burroughs

Royal Free Hospital, London, UKIntroductionBackground of the European Liver Transplant RegistrySince 1968 the European Liver Transplant Registry (ELTR) collectsprospectively the data of liver transplantation (LT) in 145 centersall over Europe. It represents more than 95% of the overallEuropean data compared to the published official figures [1]. Thiscollectionismadeprospectivelythroughastandardizedquestion-naire. The first part of the questionnaire includes items regardingdate andindicationfor LT,donor andrecipientdata, surgical tech-niqueofLT,andtheimmediatepostoperativeimmunosuppressiontherapy. The second part concerns graft and patient outcome, andimmunosuppressive regimen follow-up. Participation in the ELTRis voluntary and a standard computerized database is provided tocontributing centers with detailed instructions for the collectionof accurate and uniform information [2].Along with reports concerning LT for specific hepatic diseases[3–12],ELTRhasallowedthedevelopmentofriskmodelsforliver-transplantation mortality according to the characteristics of thedonor and recipient, and of the transplant procedure [13,14].Qualityofthedataisassessedroutinely.Aregularauditingpro-cessisconductedeachyeartoensurethereliabilityofthescientificanalysis of the data, a control of the good adequacy between ELTRquestionnaire and patient charts is performed by randomly con-ductedauditvisits.ResultsoftheseauditvisitshaveindicatedthatELTR data were reliable and the scientific results of ELTR can beconsidered credible and representative of LT in Europe [15–18].In addition, a control quality program has been developed inter-nally. The data are subjected to checks for completeness, consis-tency, and range. Comprehensive logical intra- and inter-updatesare performed. Moreover, the ELTR has established agreementswith the European Organ Sharing Organizations (OSO): UnitedKingdom Transplant Service Support Authority (UKTransplant),Spanish Organizacion Nacional de Transplantes (ONT), Scandina-vian Scanditransplant (SKT), Dutch Transplant Foundation (NTS),Eurotransplant (ET), French Agence de la Biomedecine (ABM) toexchangedatacollectedfromEuropeanCentersandtocrosscheckcommon data between OSO and ELTR.Patients and methodsWe have first considered all data since 1968 to show the evolu-tion of results of LT in Europe since its initial development. Therest of the analysis has been undertaken during two differentperiods: (a) from January 1988 to December 2009 (89,865 LT –80,347 patients), where the date from January 1988 was chosenJournal of Hepatology 2012 vol. 57


Annals of Surgery | 1996

Surgical treatment in proximal bile duct cancer. A single-center experience.

R. Pichlmayr; Arved Weimann; Jürgen Klempnauer; Karl J. Oldhafer; H. Maschek; Günter Tusch; Burckhardt Ringe

OBJECTIVES The authors evaluated the experience and results of a single center in surgical treatment of proximal bile duct carcinoma. SUMMARY BACKGROUND DATA Whenever feasible, surgery is the appropriate treatment in proximal bile duct carcinoma. To improve survival rates and with special regard to liver transplantation, the extent of surgical radicalness remains an open issue. PATIENTS AND METHODS Retrospective analysis of 249 patients who underwent surgery for proximal bile duct carcinoma via the following procedures: resection (n = 125), liver transplantation (n = 25), and exploratory laparotomy (n = 99). Survival rates were calculated according to the Kaplan-Meier method, uni- and multivariate analysis of prognostic factors, and log rank test (p < 0.05). RESULTS Survival rates after resection and liver transplantation are correlated with international Union Against Cancer (UICC) tumor stage (resection: overall 5-year, 27.1%; stage I and II, 41.9%; stage IV, 20.7%; liver transplantation: overall 5-year, 17.1%; stage I and II, 37.8%; stage IV, 5.8%). Significant univariate prognostic factors for survival after liver resection were lymph node involvement (N category), tumor stage, tumor-free margins, and vascular invasion; for transplantation, they were local tumor extent, N category, tumor stage, and infiltration of liver parenchyma. For resection and transplantation, a multivariate analysis showed prognostic significance of tumor stage and tumor-free margins. CONCLUSION Resection remains the treatment of choice in proximal bile duct carcinoma. Whenever possible, decisions about resectability should be made during laparotomy. With regard to the observation of long-term survivors, liver transplantation still can be justified in selected patients with stage II carcinoma. It is unknown whether more radical procedures, such as liver transplantation combined with multivisceral resections, will lead to better outcome in advanced stages. With regard to palliation, surgical drainage of the biliary system performed as hepatojejunostomy can be recommended.


The Lancet | 2006

3-month and 12-month mortality after first liver transplant in adults in Europe: predictive models for outcome

Andrew K. Burroughs; Caroline Sabin; Keith Rolles; V. Delvart; Vincent Karam; John A. C. Buckels; John O'Grady; Denis Castaing; Jürgen Klempnauer; Neville V. Jamieson; Peter Neuhaus; Jan Lerut; Jean de Ville de Goyet; S. Pollard; Mauro Salizzoni; Xavier Rogiers; Ferdinand Mühlbacher; Juan Carlos Garcia Valdecasas; Christopher Broelsch; Daniel Jaeck; Joaquín Berenguer; Enrique Moreno González; René Adam

BACKGROUND Mortality after liver transplantation depends on heterogeneous recipient and donor factors. Our aim was to assess risk of death and to develop models to help predict mortality after liver transplantation. METHODS We analysed data from 34,664 first adult liver transplants from the European Liver Transplant Registry to identify factors associated with mortality at 3-months (n=21,605 in training dataset) and 12-months (n=18,852 in training dataset) after transplantation. We used multivariable logistic regression models to generate mortality scores for each individual, and assessed model discrimination and calibration on an independent validation dataset (n=9489 for 3-month model and n=8313 for 12-month model). FINDINGS 2540 of 21,605 (12%) individuals in the 3-month training sample had died by 3 months. Compared with those transplanted in 2000-03, those transplanted earlier had a higher risk of death. Increased mortality at 3-months post-transplantation was associated with acute liver failure (adjusted odds ratio 1.61), donor age older than 60 years (1.16), compatible (1.22) or incompatible (2.07) donor-recipient blood group, older recipient age (1.12 per 5 years), split or reduced graft (1.96), total ischaemia time of longer than 13 h (1.38), and low United Network for Organ Sharing score (score 1: 2.43; score 2: 1.67). However, cirrhosis with hepatocellular carcinoma, alcohol cirrhosis, hepatitis C or primary biliary cirrhosis, donor age 40 years or younger, or less, hepatitis B, and larger size of transplant centre (> or = 70 transplants per year) were associated with improved early outcomes. The 3-month mortality score discriminated well between those who did and did not die in the validation sample (C statistic=0.688). We noted similar findings for 12-month mortality, although deaths were generally underestimated at this timepoint. INTERPRETATION The 3-month and 12-month mortality models can be effectively used to assess outcomes both within and between centres. Furthermore, the models provide a means of assessing the risk of post-transplantation mortality, giving clinicians important data on which to base strategic decisions about transplant policy in particular individuals or groups.


Journal of Clinical Oncology | 1997

Resectional surgery of hilar cholangiocarcinoma: a multivariate analysis of prognostic factors.

Jürgen Klempnauer; Ridder Gj; R. von Wasielewski; Martin Werner; Arved Weimann; R. Pichlmayr

PURPOSE To define the prognostic factors after surgical resection of bile duct carcinomas at the hepatic bifurcation. PATIENTS AND METHODS The retrospective single-center experience details 151 patients after surgical resection of central bile duct carcinoma performed between 1971 and 1995. Tumor removal was accomplished by resection of the bile duct bifurcation either alone (group I, n = 33), in combination with hepatic resection (group II, n = 77), or combined with hepatic and vascular resection (group III, n = 41). Survival analysis was performed by the Kaplan-Meier method and the relationship between each of the clinicopathologic variables and survival was assessed by the log-rank test. Multivariate results were confirmed using Cox regression. RESULTS The overall hospital mortality rate was 9.9% and depended on the extent of resection (group 1, 6.1%; group II, 7.8%; group III, 17.1%). After exclusion of hospital deaths, the overall patient survival rate was 28.4% at 5 and 15.5% at 10 years, with a median survival duration of 2.05 +/- 0.23 years. Univariate survival analysis identified tumor size, lymph node metastases, residual tumor stage, and tumor grading as factors with a statistically significant prognostic impact. Survival prognosis was not influenced by the site of the tumor according to the classification of Bismuth and Corlette, extent of resection, International Union Against Cancer (UICC) stage, perineural and vascular invasion, age, or sex. In a multivariate Cox analysis, only lymph node metastases and residual tumor stage proved to be of independent prognostic significance. CONCLUSION Resection of central bile duct carcinoma is feasible in many patients and a favorable outcome after resection is mainly determined by curative resection and the absence of lymph node metastases.


The Lancet | 2001

Replacement of calcineurin inhibitors with mycophenolate mofetil in liver-transplant patients with renal dysfunction: a randomised controlled study

Hans J. Schlitt; Annette Barkmann; K. Böker; Nikos Emmanouilidis; Jens Rosenau; Matthias J. Bahr; Günter Tusch; Michael P. Manns; Björn Nashan; Jürgen Klempnauer

BACKGROUND Renal dysfunction is a major complication of long-term immunosuppressive therapy with calcineurin inhibitors (CNI) in liver-transplant recipients. We undertook a randomised study to assess the safety and efficacy of CNI withdrawal and replacement by mycophenolate mofetil. METHODS 28 people who had had renal dysfunction attributable to suspected CNI toxicity after liver transplantation participated in the study. We replaced CNI with mycophenolate mofetil in a stepwise pattern in half the group (study patients); the other half (controls) stayed on CNI immunosuppression. Renal function, blood pressure, uric acid, and blood lipids were measured before and 6 months after study entry. Side-effects of medication and graft function were recorded throughout the study. FINDINGS At the end of the study, mean (SD) serum creatinine had fallen by 44.4 (48.7) micromol/L in study patients compared with 3.1 (14.3) micromol/L in controls; a mean difference of 41.3 micromol/L (95% CI 12.4-70.2). Moreover, systolic and diastolic blood pressure, and serum uric acid decreased significantly in the study group but not in the control group (mean [95% CI] between group differences 10.8 mm Hg [3.0-18.6], 5.0 mm Hg [0.9-9.2], and 83.1 micromol/L [12.7-153.6], respectively). There were no changes in cholesterol or triglyceride concentrations in either group. Side-effects were reported by eight of the study patients. Three reversible episodes of acute graft rejection occurred in study patients during mycophenolate mofetil monotherapy, whereas none occurred in the control group. INTERPRETATION Substitution of CNI by mycophenolate mofetil can improve renal function, blood pressure, and uric acid concentration of liver-transplant patients, but there is an increased rejection risk with mycophenolate mofetil monotherapy.


World Journal of Surgery | 1997

Benign Liver Tumors: Differential Diagnosis and Indications for Surgery

Arved Weimann; Burckhardt Ringe; Jürgen Klempnauer; P. Lamesch; Klaus F. Gratz; Mathias Prokop; H. Maschek; Günter Tusch; R. Pichlmayr

Abstract. The differential diagnosis for hemangioma, focal nodular hyperplasia (FNH), and hepatocellular adenoma may be difficult. Reliable diagnosis is mandatory for the decision of whether to apply surgery or observation. Experience with long-term observation in nonoperated patients with hemangioma and FNH is limited. A group of 437 patients from a single institution were analyzed with regard to a diagnostic algorithm, the indications for surgery, and observation. There were 238 hemangiomas, 150 cases of FNH, 44 adenomas, and 5 mixed tumors. Of the 437 patients, 173 underwent surgery; 103 with hemangioma and 54 with FNH were observed at our own institution, whereas 117 patients underwent follow-up elsewhere or were lost. Among the operated patients with confirmed histology, a good diagnostic yield was found for a combination of ultrasonography (US), contrast (bolus)-enhanced computed tomography (CT), and labeled red blood cell (RBC) scanning: sensitivity 85.7%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 81.8%, and accuracy 91.3%. For FNH the combination of US and CT plus cholescintigraphy showed a sensitivity 82.1%, specificity 97.1%, PPV 95.8%, NPV 84.6%, and accuracy 90.3%. Surgical mortality was 0.6%. Observation of patients with hemangioma and FNH for a median of 32 months revealed no increase in tumor size in 80% and a decrease in fewer than 7%. There was no tumor rupture and no evidence of malignant transformation. We concluded that liver hemangioma and FNH can be differentiated from adenoma with high sensitivity, specificity, and accuracy by labeled RBC scanning and cholescintigraphy in combination with US and contrast-enhanced CT. In the case of symptoms or an equivocal diagnosis with respect to adenoma or hepatocellular carcinoma, surgery can be performed with very low risk. Because in asymptomatic patients with observed hemangioma or FNH no increase of tumor size can be expected for many years, the indications for surgery must be carefully evaluated.


Journal of Hepatology | 2001

Lamivudine and low-dose hepatitis B immune globulin for prophylaxis of hepatitis B reinfection after liver transplantation – possible role of mutations in the YMDD motif prior totransplantation as a risk factor for reinfection

Jens Rosenau; Matthias J. Bahr; Hans L. Tillmann; Christian Trautwein; Jürgen Klempnauer; Michael P. Manns; K. Böker

BACKGROUND/AIMS Reinfection with hepatitis B virus (HBV) after liver transplantation (OLT) is associated with an unfavourable clinical course. Lamivudine/hepatitis B immune globulin (HBIG) combination treatment reduces reinfection rates. However, it is unclear at what time point lamivudine should be started and which HBIG doses are sufficient. METHODS Twenty-one patients receiving combination treatment were studied. Lamivudine was started up to 16.5 months before OLT and continued thereafter. HBIG was started intraoperatively and continued according to anti-HBs-titers. Median follow-up after OLT was 20 months. RESULTS Eleven patients received lamivudine pretreatment for >2 (median 6) months due to initial HBV-DNA-positivity (median 749 pg/ml). After initial lamivudine response HBV-DNA increased in two of them to concentrations above 10 pg/ml prior to OLT. Both had developed mutations in the YMDD motif and suffered from HBV reinfection 13 and 75 days postoperatively. Individual HBIG consumption was highly variable (range 787-4,766 lU/month). Twenty-two percent of anti-HBs titers measured before HBIG administration were below 100 IU/l. CONCLUSIONS Combined reinfection prophylaxis with lamivudine and HBIG is effective in patients with controlled viral replication at the time of OLT. However, pretransplantation lamivudine resistance is a risk factor for reinfection. Low dose HBIG maintenance therapy individualized according to anti-HBs-titers appears to be tenable.


Pharmacological Reviews | 2004

Liver-Enriched Transcription Factors in Liver Function and Development. Part II: the C/EBPs and D Site-Binding Protein in Cell Cycle Control, Carcinogenesis, Circadian Gene Regulation, Liver Regeneration, Apoptosis, and Liver-Specific Gene Regulation

Harald Schrem; Jürgen Klempnauer; Jürgen Borlak

In the first part of our review (see Pharmacol Rev 2002;54:129-158), we discussed the basic principles of gene transcription and the complex interactions within the network of hepatocyte nuclear factors, coactivators, ligands, and corepressors in targeted liver-specific gene expression. Now we summarize the role of basic region/leucine zipper protein family members and particularly the albumin D site-binding protein (DBP) and the CAAT/enhancer-binding proteins (C/EBPs) for their importance in liver-specific gene expression and their role in liver function and development. Specifically, regulatory networks and molecular interactions were examined in detail, and the experimental findings summarized in this review point to pivotal roles of DBP and C/EBPs in cell cycle control, carcinogenesis, circadian gene regulation, liver regeneration, apoptosis, and liver-specific gene regulation. These regulatory proteins are therefore of great importance in liver physiology, liver disease, and liver development. Furthermore, interpretation of the vast data generated by novel genomic platform technologies requires a thorough understanding of regulatory networks and particularly the hierarchies that govern transcription and translation of proteins as well as intracellular protein modifications. Thus, this review aims to stimulate discussions on directions of future research and particularly the identification of molecular targets for pharmacological intervention of liver disease.


Transplantation | 2002

Ki67, E-cadherin, and p53 as prognostic indicators of long-term outcome after liver transplantation for metastatic neuroendocrine tumors.

Jens Rosenau; Matthias J. Bahr; Reinhard von Wasielewski; Michael Mengel; Hartmut Schmidt; Björn Nashan; Hauke Lang; Jürgen Klempnauer; Michael P. Manns; K. Boeker

BACKGROUND Patients suffering from hepatic metastases of neuroendocrine tumors (NET) are potential candidates for orthotopic liver transplantation. Because recurrence rates are high and outcome is variable, prognostic indicators are required. The aim of our study was to identify predictors of long-term survival with a focus on the impact of tumor biology. METHODS We retrospectively analyzed 19 patients who received an orthotopic liver graft for metastatic NET at the Medizinische Hochschule Hannover. Expression of Ki67, E-cadherin, and p53 was studied immunohistochemically in metastases of neuroendocrine tumors of the explanted livers. RESULTS Patients were followed up to 146 months after liver transplantation. Six patients died during follow-up. The resulting 1-, 5-, and 10-year survival rates are 89%, 80%, and 50%, respectively. All deaths during long-term follow-up were tumor-associated. Recurrence was diagnosed in 12 patients between 2 weeks and 48 months after liver transplantation. Three patients are without tumor recurrence more than 8 years after liver transplantation. Survival in the 5 patients with low Ki67 and regular E-cadherin staining was significantly better than in the 12 patients with high Ki67 or aberrant E-cadherin expression (7-year survival 100% vs. 0%, respectively, log rank P=0.007). p53 expression did not significantly improve prognostic accuracy. CONCLUSIONS We conclude that analysis of Ki67 and E-cadherin expression may improve the identification of patients with a favorable prognosis after liver transplantation for metastatic neuroendocrine tumors.


Journal of The American Society of Nephrology | 2010

Five-Year Safety and Efficacy of Belatacept in Renal Transplantation

Flavio Vincenti; Gilles Blancho; Antoine Durrbach; Peter J. Friend; Josep M. Grinyó; Philip F. Halloran; Jürgen Klempnauer; Philippe Lang; Christian P. Larsen; Ferdinand Mühlbacher; Björn Nashan; Jean-Paul Soulillou; Yves Vanrenterghem; Thomas Wekerle; M. Agarwal; Sheila Gujrathi; Jinshan Shen; Rebecca Shi; Robert Townsend; Bernard Charpentier

Belatacept is a first-in-class co-stimulation blocker in development for primary maintenance immunosuppression. A Phase II study comparing belatacept with cyclosporine (CsA) for prevention of acute rejection and protection of renal function in kidney transplant recipients demonstrated similar efficacy and significantly higher measured GFR at 1 year for belatacept, but the incidence of posttransplantation lymphoproliferative disorder was higher. Here, we present the results for the extension of this trial, which aimed to assess long-term safety and efficacy of belatacept. Seventy-eight of 102 patients who were receiving belatacept and the 16 of 26 who were receiving CsA completed the long-term extension period. GFR remained stable in patients who were receiving belatacept for 5 years, and the incidences of death/graft loss or acute rejection were low. The frequencies of serious infections were 16% for belatacept and 27% for CsA, and neoplasms occurred in 12% of each group. No patients who were treated with belatacept and one patient who was treated with CsA developed posttransplantation lymphoproliferative disorder during the follow-up period. Serious gastrointestinal disorders occurred more frequently with belatacept (12% belatacept versus 8% CsA), and serious cardiac disorders occurred more frequently with CsA (2% belatacept versus 12% CsA). Pharmacokinetic analyses showed consistent exposure to belatacept over time. CD86 receptor saturation was higher in patients who were receiving belatacept every 4 weeks (74%) compared with every 8 weeks (56%). In conclusion, this study demonstrated high patient persistence with intravenous belatacept, stable renal function, predictable pharmacokinetics, and good safety with belatacept over 5 years.

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Frank Lehner

Hannover Medical School

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