Attila Doros

Analysis of differences in outcome of two European liver transplant centers

Authors analyzed the differences in the outcome of two European liver transplant centers differing in case volume and experience. The first was the Transplantation and Surgical Clinic, Semmelweis University, Budapest, Hungary (SEB) and the second the University Medical Center Groningen, Groningen, The Netherlands (UMCG). We investigated if such differences could be explained. The 1‐, 3‐ and 5‐year patient survival in the UMCG was 86%, 80%, and 77% compared with 65%, 56%, and 55% in SEB. Graft survival at the same time points was 79%, 71%, and 66% in the UMCG and 62%, 55%, and 53% in SEB. Significant differences were present regarding the donor and recipient age, diagnosis mix, disease severity and operation variables, per‐operative transfusion rate, vascular complications, postoperative infection rate, and need for renal replacement. To determine factors correlating with survival, a separate uni‐ and multivariate analysis was performed in each center individually, between study parameters and patient survival. In both centers, peri‐operative red blood cell (RBC) transfusion rate was a significant predictor for patient survival. The difference in blood loss can be explained by different operation techniques and shorter operation time in SEB, with consequently less time spent on hemostasis. It was jointly concluded that measures to reduce blood loss by adapting the operation technique might lead to improved survival and reduced morbidity.

Biliary complications after liver transplantation

Biliary complications (BCs) remain one of the most outstanding factors influencing long-term results after orthotopic liver transplantation. The authors carried out a systematic overview of 1720 papers since 2008, and focused on 45 relevant ones. Among 14,411 transplanted patients the incidence of BCs was 23%. Biliary leakage occurred in 8.5%, biliary stricture in 14.7%, mortality rate was 1–3%. Risk factors: preoperative sodium level; p = 0.037, model of end-stage liver disease score >25; p = 0.048, primary sclerosing cholangitis; p = 0.001, malignancy; p = 0.026, donor age >60, macrovesicular graft steatosis; p = 0.001, duct-to-duct anastomosis; p = 0.004, long anhepatic phase; p = 0.04, cold ischemic time >12 h; p = 0.043, use of T-tube; p = 0.032, insufficient flush of bile ducts; p = 0.001, acute rejection; p = 0.003, cytomegalovirus infection; p = 0.004 and hepatic artery thrombosis; p = 0.001. The management was surgical in case of biliary leakage, and interventional radiology or endoscopic retrograde cholangiopancreatography in case of biliary stricture. Mapping of miRNA profile is a new field of research. Nemes–Doros score is a useful tool in the estimation of hepatic artery thrombosis. Management of BCs requires a multidisciplinary expert team.

Epidural Anesthesia? No of Course

Although the contraindications for thoracic epidural anesthesia (TEA) are well defined, the debate continues about whether TEA improves outcomes. Pro and con trials and a metaanalysis in the past have yielded equivocal results; they did not deal with new vascular intervention or drugs. The benefit of TEA in surgery is to provide analgesia. In subgroups, TEA can decrease the mortality and morbidity. In contrast, the cost can increase in the situation of a complication that is opposite to the side effects is rare, but the impairment caused by them is out of proportion to the benefits. Primary or secondary prophylaxis with antithrombotic drugs is increasing in developed countries because of the increasing cardiovascular interventions and aging of the population. The neuroaxial guidelines are useful, but the changing of the coagulation profile after hepatectomy is not included in them. The decision to use TEA in liver surgery must be individualized with steps planned from the beginning. TEA suitability is based on an evaluation of the contraindications, comorbidities, coagulation profiles, hepatic reserve, and balance of benefits and risks. The insertion or withdrawal of the epidural catheter should be made with care according to the neuroaxial guidelines and in the presence of a normal TEG. The decreasing level of prothrombin content and platelet counts after hepatectomy should be closely monitored every 2 to 5 days.

MicroRNA profile before and after antiviral therapy in liver transplant recipients for hepatitis C virus cirrhosis

Management of hepatitis C virus (HCV) recurrence is a major challenge after liver transplantation. Significant dysregulated expression of HCV receptors (i.e. claudin‐1, occludin, tetraspanin CD81, scavenger receptor type B1) has been shown recently during HCV infection. This might facilitate hepatocytic entry and reinfection of HCV. MicroRNAs (miRs) play role in the regulation of gene expression. We aimed to characterize miR expression profiles related to HCV infection and antiviral therapy in adult liver transplant recipients, with special emphasis on miRs predicted to target HCV receptors.

Malignant Peripheral Nerve Sheath Tumor of the Liver: A Case Report

A large, rapidly growing malignant peripheral nerve sheath tumor (MPNST) of the liver in a young female patient, not associated with von Recklinghausen’s disease, is presented. Diagnosis was based on detailed immunohistochemical and electromicroscopic examination beside the characteristic H&E picture. As far as we know, this is the first reported, unambiguously proven “de novo” MPNST in the liver. Differential diagnostic problems are discussed and a review of the literature is given.

Renal cell carcinoma of the native kidney: a frequent tumor after kidney transplantation with favorable prognosis in case of early diagnosis.

INTRODUCTION The frequency of malignant tumors as a cause of death is increasing among kidney transplant patients. The aim of our study was to characterize kidney tumors occurring in the native kidneys of renal transplanted patients, and to determine their impact on recipient survival. METHODS We retrospectively analyzed the 43/3003 (1.43%) renal cell carcinomas (RCC) in the native kidneys of patients transplanted between 1973 and 2010. RESULTS During this period we diagnosed 293 posttransplant tumors, 14.6% of which were RCC. The male/female ratio was 2.1:1. The mean age of recipients at the time of tumor detection was 52.4 ± 12.1 years. The mean time from transplantation to diagnosis was 72.4 ± 61.6 months. RCC occurred on both sides in similar numbers. Tumors were multifocal in 8 cases. According to TNM staging, RCC was stage I in 38 cases. The histologic type was clear cell (n=27), papillary (n=13), chromophobe (n=2) or sarcomatoid (n=1). Radical nephrectomy was performed in 41 cases. Immunosuppressive management was converted to proliferation signal inhibitors in 27 patients (sirolimus n=19 or everolimus n=8). Fifteeen patients died at a mean survival time of 38.9 ± 62.4 months with 28 patients still alive at a mean follow-up 43.8 ± 35.6 months. Cumulative survival according to the Kaplan-Meier method was 79.2% at 1 year, 66.1% at 5 years, and 59.0% at 10 years. The patient survival rate was better among papillary than clear cell RCC (P=.038). CONCLUSION RCC was the second most frequent tumor among kidney transplanted patients at our center. The diagnosis established at an early stage in the majority of cases, leading to favorable patient survivals. A regular yearly abdominal ultrasound screening is suggested for early tumor diagnosis.

The use of autologous rectus facia sheath for replacement of inferior caval vein defect in orthotopic liver transplantation

Occasionally, during liver transplantation, vascular reconstructions have to be performed. Donor vessels can be harvested for this purpose. However, when these are lacking, alternatives should be available. A possible alternative can be the use of autologous rectus fascia sheath, folded as a tube with the mesothelium on the inside. Earlier experimental studies from our centre showed the successful use of the rectus fascia sheath graft in vascular defects in animal experiments. This report describes the first use of this autologous tubular graft for replacement of the inferior caval vein interponate during liver transplantation in men.

The Significance of the Circumaortic Left Renal Vein and Other Venous Variations in Laparoscopic Living Donor Nephrectomies

Among the several vascular variation those concerning the venous system of the kidneys show the most significant variability. They often play an important role when it comes to choosing the kidney to be removed for transplantation. Based on our prior studies, we have surveyed these variations. When performing a laparoscopic living donor nephrectomy owing to the limited field of vision and the restricted possibilities for preparation, preoperative radiologic planning is of utmost importance. We evaluated 55 donors who underwent laparoscopic nephrectomies using the 16-section multidetector-row computed tomography angiography. Among the donors who underwent surgeries we observed circumaortic veins (CAV) in three cases, retroaortic veins in 6 cases, multiple renal veins in 10 cases, and a lumbar vein draining into the left renal vein (RV) in 30 cases. In the 2 cases wherein CAVs were discovered, the team decided to use the other kidney. In 1 case, due to a short right RV, we chose the left kidney. The complex development of the CAV that is sometimes difficult to reconstruct in 3D poses a challenge for both the radiologist and the surgeon.

New-onset diabetes mellitus after liver transplantation

A de novo diabetes mellitus a majatultetes gyakori szovődmenye. Celkitűzes: A de novo diabetes gyakorisagat, jelentőseget es a kockazati tenyezők szerepet vizsgaltuk. Modszer: 1995 es 2009 kozott 310 majatultetett beteg adatait dolgoztuk fel retrospektiv modszerrel. De novo diabetest allapitottunk meg, ha az ehomi vercukor a 3. posztoperativ honapon tul ismetelten >6,8 mmol/l volt, es/vagy a majatultetes utan tartos, a 3. posztoperativ honapot meghaladoan is fenntartott antidiabetikus terapia indult. Eredmenyek: De novo diabetes a betegek 20%-anal (63 beteg) alakult ki. A de novo es a kontrollcsoport kozott az alabbiakban talaltunk kulonbseget. Donor-testtomegindex (24±3 vs. 22,4±3,6 kg/m 2 , p = 0,003), ferfi nem (58% vs. 33%, p = 0,002). Recipienseletkor (47,6±7,2 vs. 38,3±14,6 ev, p<0,001), -testtomegindex (26,7±3,8 vs. 23,3±5,6 kg/m 2 , p<0,001), ferfi nem (60% vs. 44%, p = 0,031). A de novo diabetesesek csoportjaban a betegek 66%-at HCV talajan kialakult cirrhosis miatt transzplantaltak, a kontrollcs...UNLABELLED New-onset diabetes is a common complication after liver transplantation. AIM We aimed to analyze the incidence and rate of known risk factors and the impact of new-onset diabetes mellitus on postoperative outcome. METHODS We retrospectively evaluated the files of 310 patients who underwent liver transplantation between 1995 and 2009. Definition of new-onset diabetes included: repeated fasting serum glucose >6.8 mmol/l and/or sustained antidiabetic therapy that was present 3 months after transplantation. RESULTS New-onset diabetes occurred in 63 patients (20%). Differences between the new-onset and the control group were the donor body mass index (24+/-3 vs. 22.4+/-3.6 kg/m 2 , p = 0.003), donor male gender (58% vs. 33%, p = 0.002), and recipient age (47.6+/-7.2 vs. 38.3+/-14.6 year, p<0.001), body mass index (26.7+/-3.8 vs. 23.3+/-5.6 kg/m 2 , p<0.001), male gender (60% vs. 44%, p = 0.031). The 66% of patients with new-onset diabetes were transplanted with cirrhosis caused by hepatitis C virus infection, while in the control group the rate was 23% (p<0.001). Cumulative patient survival rates at 1, 3, 5 and 8 year were 95%, 90.6%, 88% and 88% in the control group, and 87%, 79%, 79% and 64% in the de novo group, respectively (p = 0.011). Cumulative graft survival rates at 1, 3, 5 and 8 year in the control group were 92%, 87%, 86% and 79%, in the de novo diabetes group the rates were 87%, 79%, 79%, 65%, respectively (p = NS). In case of early recurrence (in 6 months), majority of patients developed new-onset diabetes (74% vs. control 26%, p = 0.03). More patients had more than 10 times higher increase of the postoperative virus titer correlate to the preoperative titer in the de novo diabetes group (53% vs. 20%, p = 0.028). Mean fibrosis score was higher in new-onset group one year after the beginning of antiviral therapy (2.05+/-1.53 vs. 1.00+/-1.08, p = 0.039). CONCLUSIONS Risk factors for new-onset diabetes after transplantation are older age, obesity, male gender and cirrhosis due to hepatitis C infection. The early recurrence, viremia and more severe fibrosis after antiviral therapy have an impact on the occurrence of new-onset diabetes in hepatitis C positive patients.

Serum albumin coating of demineralized bone matrix results in stronger new bone formation

Blood serum fractions are hotly debated adjuvants in bone replacement therapies. In the present experiment, we coated demineralized bone matrices (DBM) with serum albumin and investigated stem cell attachment in vitro and bone formation in a rat calvaria defect model. In the in vitro experiments, we observed that significantly more cells adhere to the serum albumin coated DBMs at every time point. In vivo bone formation with albumin coated and uncoated DBM was monitored biweekly by computed tomography until 11 weeks postoperatively while empty defects served as controls. By the seventh week, the bone defect in the albumin group was almost completely closed (remaining defect 3.0 ± 2.3%), while uncoated DBM and unfilled control groups still had significant defects (uncoated: 40.2 ± 9.1%, control: 52.4 ± 8.9%). Higher density values were also observed in the albumin coated DBM group. In addition, the serum albumin enhanced group showed significantly higher volume of newly formed bone in the microCT analysis and produced significantly higher breaking force and stiffness compared to the uncoated grafts (peak breaking force: uncoated: 15.7 ± 4 N, albumin 46.1 ± 11 N). In conclusion, this investigation shows that implanting serum albumin coated DBM significantly reduces healing period in nonhealing defects and results in mechanically stronger bone. These results also support the idea that serum albumin coating provides a convenient milieu for stem cell function, and a much improved bone grafting success can be achieved without the use of exogenous stem cells.