Safety of Direct-Acting Antiviral Therapy Regarding Renal Function in Post-Liver Transplant Patients Infected with Hepatitis C Virus and a 100% 12-Week Sustained Virologic Response-A Single-Center Study.

BACKGROUND: Patients after liver transplantation (LT) with hepatitis C virus (HCV) infection often suffer from renal or hepatic impairment. Treating patients after LT with direct-acting antivirals (DAA) might result in decreasing renal function due to interaction of DAA and immunosuppressive therapy. In this single-center study we analyzed clinical parameters of 18 HCV-infected patients treated with DAA therapy after LT. METHODS: The primary end points were change of renal function (glomerular filtration rate) and sustained virologic response 12 weeks after therapy (SVR12). For secondary end points, we investigated the influence of DAA therapy on transaminases, bilirubin, international normalized ratio, noninvasive fibrosis measurement, and Model for End-Stage Liver Disease (MELD) score. RESULTS: Five out of 18 patients treated with DAA suffered from renal impairment stage 2, and 7 patients of renal impairment stage 3. Renal function at SVR12 was not influenced by preexisting renal impairment (P > .5), type of immunosuppressant (P > .5), or type of DAA regimen (P > .5). All patients reached SVR12. The levels of transaminases and bilirubin declined rapidly, as expected. Ten out of 18 patients already suffered from cirrhosis or liver fibrosis >F3 according to noninvasive measurement before initiation of treatment. Single-point acoustic radiation force impulse imaging improved in 9 patients (P = .012). In 7 patients, MELD score improved owing to the decrease of bilirubin levels. In 6 patients it worsened. CONCLUSIONS: DAA therapy in LT patients was effective and safe in this single-center real-life cohort. Renal function was not influenced by the administered drug combinations, even in patients with preexisting renal impairment.

[Biliodigestive anastomosis: indications, complications and interdisciplinary management]. / Biliodigestive Anastomosen: Indikationen, Komplikationen und interdisziplinäres Management.

Techniques for biliodigestive anastomoses are a frequent indication in primary surgical interventions. Moreover, they are required to manage secondary complications of hepatobiliary surgery. Evidence for the management of complications following biliodigestive anastomoses is low. Biliodigestive anastomoses can be performed as hepaticojejunostomy, hepatojejunostomy/portoenterostomy and hepaticoduodenostomy using running or single stitch suture techniques. Complication management in the hands of experienced hepatopancreatobiliary surgeons should consider a time delay to the primary operation and an interdisciplinary surgical and/or endoscopic or radiologic interventional approach. The therapy may be protracted and requires repeated critical reflection of the particular complication.

Eosinophilic cholangitis and wirsungitis as cause of simultaneous bile duct obstruction and pancreatitis.

Eosinophilic cholangitis is a rare clinical entity characterised by transmural eosinophilic infiltration of the biliary system. The aetiology of this disease is still unclear. We report on a 49-year-old male patient who presented with symptoms of obstructive jaundice and imaging suggestive for periampullary carcinoma. After partial pancreatoduodenectomy for suspected pancreatic cancer, pathology revealed massive eosinophilic cholecystitis as well as intra- and extrahepatic eosinophilic cholangitis with pseudopolypoid papillary lesions. Our case illustrates the diagnostic pitfalls in eosinophilic cholangitis as careful imaging procedures - optimally interdisciplinary - should be considered and performed in such patients. In conclusion, eosinophilic cholangitis is an uncommon, inflammatory condition that needs to be considered as a differential diagnosis for periampullary malignancies.

Contrast-enhanced ultrasound improves real-time imaging of ablation region during radiofrequency ablation: preliminary results.

PURPOSE: To assess the added value of depicting tumour microvascularisation, using dynamic contrast enhanced (CEUS), during radiofrequency ablation, as a means of achieving a complete ablation (CA) of malignant liver lesions. MATERIAL AND METHODS: 18 consecutive patients (2 female, 16 male, age range 52-79 years, mean 64.1 ± 9.9 years) with 22 histologically confirmed hepatic malignancies (HCC: n = 10, liver metastases: n = 12) underwent RFA. Before RFA treatment, conventional US, CEUS and contrast enhanced CT (ceCT) of the liver were performed. During the CT-guided RFA procedure, CEUS was performed to asses the ablation defect. In case of partial ablation a subsequent ablation was performed with a corrected electrode position and evaluated again using CEUS. This procedure was repeated until a CA was achieved. The number of ablations per patient was recorded. Secondary efficacy parameters assessed were lesion detectability in the different imaging modalities and contrast phases. RESULTS: Overall intraprocedural CEUS led to a change in therapeutic management in 59% of cases, resulting in 17 additional ablation cycles. Lesion detectability during CT Fluoroscopy was the sole statistical significant predictor of incomplete ablations (p = 0.008). The mean number of ablations for detectable lesions was 1.27 vs. 2.27 ablations for not detectable lesions (p = 0.002). The combined CT and CEUS RFA procedure led to a CA for all treated lesions in follow up 3 month post intervention. CONCLUSION: CEUS does allow a reliable and immediate assessment of therapeutic efficacy of percutaneous RFA procedures of malignant liver lesions, through the continuous dynamic evaluation of tumour microcirculation.

Characterization of microvascularization of liver tumor lesions with high resolution linear ultrasound and contrast enhanced ultrasound (CEUS) during surgery: First results.

AIM: Evaluation of high resolution linear ultrasound and intra-operative linear contrast enhanced ultrasound (CEUS) and its benefit for the detection and characterization of tumor lesions. MATERIAL AND METHODS: Twenty patients were investigated preoperatively regarding tumor detection using CT (n = 8) or MRI (n = 12) and image fusion (VNav) (n = 3). All patients had surgery for their hepatic tumor (hepatocellular carcinoma (HCC), cholangiocellular carcinoma (CCC), metastasis, and adenoma). Ultrasound was performed intra-operatively first with B-scan using a convex probe. Than multifrequency linear transmitters (6-9 MHz, 6-15 MHz, LOGIQ E9, GE) were applied for B-scan, coulor coded Doppler sonography (CCDS) and Power Doppler followed by dynamic CEUS with Contrast Harmonic Imaging (CHI) after bolus injection of a maximum of 15 mL SonoVue®. RESULTS: In 9 cases with the use of intra-operative CEUS additional tumor lesions (diameter 4-15 mm) could be detected and were histologically confirmed after surgical resection (7 cases) or intra-operative biopsy (2 cases). Using intraoperative CEUS 64 tumor lesions could be detected compared to 51 tumor lesions detected by preoperative CT or MRI (p < 0.05). Using the 6-15 MHz multifrequency linear transducer with CHI, arterial perfusion of adenomas, neuroendocrine metastases and HCC lesions was detectable. In 3 cases a resection was not achievable. Two of these cases were treated with radio frequency ablation (RFA). The other case had no curable option due to multifocal tumor manifestation. CONCLUSION: The intra-operative use of high-resolution linear transducer techniques with CEUS offers new diagnostic perspectives for an effective liver surgery.

Innovations in contrast enhanced high resolution ultrasound improve sonographic imaging of the intestine.

The aim was to describe the perfusion pattern of the inflamed bowel wall and the surrounding tissue in inflammatory bowel disease and diverticulitis of the sigmoid colon applying a high resolution matrix transducer and the new hybrid technique. We performed contrast enhanced ultrasound (CEUS) using an updated version of the 1-5 MHz (C1-5-D convex probe) and the 6-9 MHz probe (9L-D linear probe) as well as a matrix 6-15 MHz transducer (ML 6-15-D Matrix Array Linear Probe) and updated post-processing procedures to examine microvascularization of inflamed bowel wall in Crohn's disease (11 patients), ulcerative colitis (1 patient) and diverticulitis of the sigmoid colon (2 patients). Assessment of mural microvascularization was successful as well as identification of fistulas (2 patients) and covered perforation (1 patient). Moreover analysis of time intensity curves revealed increase of signal intensity up to 20 dB. Summarizing, application of high resolution linear probes and use of updated post-processing methods substantially improve detection of inflammation-caused increased microcirculation of the bowel wall and the surrounding tissue as well as identification of complications as fistulas or covered perforations.

[Surgical treatment of liver metastases]. / Chirurgische Therapie von Lebermetastasen.

The treatment of liver metastases has become more and more complex in recent years. More individualized therapeutic concepts have become feasible by the increase in different treatment options (surgical, interventional and oncological). In the field of surgery the definition of resectability could be broadened. More extensive liver resections are being performed, which are partly carried out as staged resections after neoadjuvant chemotherapy in combination with portal vein embolization (PVE), radio frequency ablation (RFA) or other procedures in order to increase complete resection rates and patient survival. Consequently the overall 5 year survival rate of patients with resected colorectal liver metastases has doubled from 30% to nearly 60% in the past decade. Due to the complexity of the different treatment approaches an interdisciplinary assessment of the individual patient in experienced centers is necessary.

Percutaneous transluminal angioplasty as first-line treatment of transplant renal artery stenosis.

BACKGROUND: Transplant renal artery stenosis (TRAS) is a frequent complication after renal transplantation, however long-term follow-up data after interventional treatment are rare. PATIENTS: In our transplant center 11 of 264 consecutive renal transplant recipients (4.17%) were diagnosed with TRAS. In addition, TRAS occurred in 2 renal transplant recipients that had been transplanted at other centers but who had their follow-up examinations in our center. Either a rise of the serum creatinine level and/or worsened systemic hypertension or routine examination with color Doppler sonography were indications for further diagnostic workup. METHODS: Direct angiography of the transplant renal artery was performed followed by percutaneous transluminal angioplasty (PTA) after the diagnosis of TRAS was confirmed in all of these patients. RESULTS: The immediate success rate for PTA was 92.3% (12/13). Only 1 patient with a severe kinking of the transplant renal artery had to undergo surgery to restore renal function. No complications occurred after the interventions. Thereafter the patients were monitored for a mean observation period of 33.15 months. Serum creatinine levels were significantly lower after the intervention, and estimated glomerular filtration rate (eGFR) increased accordingly. With regard to blood pressure there was only a trend for lower blood pressure levels and less antihypertensive use, whereas the dose of the prescribed drugs decreased significantly with time after interventional treatment of TRAS. In addition, a long-lasting rise of the hemoglobin levels could also be demonstrated. CONCLUSION: In summary, the beneficial effect of PTA of TRAS on renal function is long-lasting. Therefore, PTA, usually combined with stent placement, should be first-line treatment in TRAS in all patients. Surgical revascularization is only warranted, if PTA fails.

Long-term outcome after multivisceral and tumor/vascular resection in patients with soft tissue sarcoma.

BACKGROUND/AIMS: Soft tissue sarcomas (STS) are rare tumors. General treatment is difficult while multimodality treatment strategies are more and more common. In these strategies, surgical resection of the primary tumor is essential to achieve local control of the tumor. In certain cases, complex resections (CR) including multivisceral and/or vascular resection are needed to achieve resection with tumor-free margins. In this study, we evaluated retrospectively the overall prognosis, morbidity, and mortality of patients treated for STS at our university hospital. PATIENTS/METHODS: Between 1992 and 2000, 24 of 154 patients with STS received multivisceral resection and four of 154 underwent vascular resection. To determine the influence of CR on overall prognosis, we compared n = 19 patients after CR with a matched control group after simple tumor resection (SR). To determine surgical morbidity and mortality the whole study group was used (n = 154, SR n = 126, CR n = 28). RESULTS: The median follow up for all patients was 6.89 years (mean 5.64 years SD 4.3) with no difference between the groups (CR vs SR: 5.4 SD 4.8 vs 5.9 SD 3.9 years; p = 0.711). Patients receiving CR had a similar overall prognosis (mean survival 9.9 years), morbidity (10.7%) and mortality (0%) compared to patients with SR (mean survival 8.5 years; morbidity 10.3%; mortality 3.96%). CONCLUSIONS: Multivisceral resection and/or vascular resection with tumor-free margins can be achieved with the same overall prognosis, same morbidity and mortality as SR. This has to be taken into account when evaluating the treatment strategy in patients with STS.

Prognostic value of the monoethylglycinexylidide (MEGX)-test prior to liver resection.

BACKGROUND/AIMS: The critical issue before major hepatic resection is to evaluate and detect patients with a potentially increased risk of hepatic failure. In this study the prognostic value of the monoethylglycinexylidide (MEGX)- liver function test was evaluated with regards to clinical course and survival after partial liver resection. METHODOLOGY: Between 1995 and 2000 a total of 55 patients (29 male, 26 female) underwent a partial liver resection at the Georg-August University of Göttingen. Forty-two patients were treated for malignant, and 13 for benign, disease. MEGX-testing was performed 15 and 30 minutes after a single-dose of 1mg/kg BW Lidocaine i.v. was applied. RESULTS: MEGX-test results after 30 minutes had significant influence on hospital mortality. Patients who died during the hospital stay showed median MEGX-30 minutes results of 32 microg/L in (4-107 microg/L) in comparison to the surviving patients with a median 68 microg/L (16-176 microg/L) (p = 0.026). Furthermore, patients with MEGX scaled categories of 3 and 4 had a significantly lower surivial at 150 days (p = 0.008) and overall (p = 0.0002). There was an indirect impact of MEGX on hospital stay, costs and mortality reflecting high fluid loss: patients with lower loss of fluid over drainages had a significantly lower mortality at 150 days (p = 0.00046) and overall (p = 0.00008), than did patients with higher fluid loss. Low MEGX-values significantly influenced long hospital stay (p = 0.00001) and high costs (p = 0.00001). Pathologic MEGX in combination with increased age, increased BMI and extensive surgical procedures including resection of over 50% volume of the liver had a significant influence on complications (p = 0.015). CONCLUSION: The preoperative MEGX-test, especially the 30 minutes value, is a useful medium to estimate the liver reserve in non-cirrhotic patients prior to liver resection. In combination with the resection volume it may be very useful to identify patients with a high risk of developing a postoperative liver failure.

Prolongation of heart allograft survival after long-term expression of soluble MHC class I antigens and vIL-10 in the liver by AAV-plasmid-mediated gene transfer.

INTRODUCTION: The essential prerequisite for successful gene therapy in vivo is an effective and long-lasting transfer of the desired gene into the respective cell type or tissue. Over the last decades, many different methods have been developed for this purpose. The use of plasmid DNA seems to be a good alternative to the commonly used viral vectors because its large-scale production is simple, and side effects are low. Unfortunately, most reports describe only short-term expression in vivo, probably due to the lack of genomic integration in the target cell. This problem can possibly be addressed by the use of adeno-associated virus plasmids (AAV plasmids), where the coding sequences are cloned between the AAV-specific inverted terminal repeats. Here, we report our results after allogeneic heart transplantation, which followed AAV-plasmid-mediated gene transfer of the rat soluble major histocompatibility complex class I antigen RT1.A(a) and viral interleukin (vIL)-10 in the "high"-responder Dark Agouti to Lewis rat strain combination. RESULTS: A high and stable long-term expression was achieved by in vivo transfection of the liver using AAV plasmids. Serum levels over 1,000 ng/ml of soluble RT1.A(a) and over 300 pg of vIL-10, respectively, were achieved. Expression levels remained high for up to several months. A mean prolongation of heart allograft survival of 1 to 2 days was demonstrated after transfection of either RT1.A(a) or vIL-10.

Immunologic considerations for therapeutic strategies utilizing allogeneic hepatocytes: hepatocyte-expressed membrane-bound major histocompatibility complex class I antigen sensitizes while soluble antigen suppresses the immune response in rats.

Understanding the immunologic effects of hepatocytes is critical because of the potential to use these cells for bioartificial livers, as a vehicle for gene transfer, and as a means to induce donor-specific immunosuppression in organ transplantation. However, this understanding is complicated by the fact that hepatocytes express membrane-bound and soluble forms of major histocompatibility complex (MHC) class I antigen, each with the potential to induce different immune responses. In the present study we first determined the immunologic effect of normal donor-derived hepatocytes in a rat heart transplant model. We then used ex vivo hepatocyte gene transfer to examine the immunologic effects of different forms of hepatocyte-expressed MHC class I antigen. Results showed that intrasplenic injection of purified, donor-strain-specific hepatocytes into recipients primes alloimmunity, as evidenced by acceleration of heart allograft rejection. Interestingly, injection of autologous hepatocytes transfected ex vivo with DNA encoding only membrane-bound donor MHC class I antigen (RT1.A(a)) also accelerated allograft rejection. However, hepatocytes transfected to express only secreted donor MHC antigen prolonged transplant survival. Limiting-dilution analysis of lymphocytes from animals treated with hepatocytes producing only secreted alloantigen showed an antigen-specific reduction in cytotoxic T lymphocyte (CTL) and helper T lymphocyte (HTL) precursors. Further analysis of CTL populations by flow cytometry revealed a relatively high percentage of nonviable cells, implying that soluble antigen promotes allospecific CTL death. In summary, this study suggests that hepatocyte-expressed MHC class I molecules have opposing immunologic effects, with the membrane-bound antigen inducing immunologic sensitization, and the soluble antigen promoting donor-specific immunosuppression.

Effective use of donor MHC class I gene therapy in organ transplantation: prevention of antibody-mediated hyperacute heart allograft rejection in highly sensitized rat recipients.

Immunologically sensitized recipients present one of the most critical problems in clinical organ transplantation today, since preformed antibodies rapidly destroy donor tissue expressing specific MHC class I antigens (Ag). Therefore, sensitized patients are either unable to receive a compatible organ, or experience a prolonged waiting period. In this study we examined the effectiveness of donor MHC class I gene therapy in preventing hyperacute rejection (HR) of rat heart allografts in passively sensitized recipients. Our gene therapy strategy to address this problem is based on the phenomenon that liver transplants, which resist antibody-mediated HR, produce soluble MHC class I Ag capable of neutralizing preformed antibodies and suppressing the immune response. To mimic this "liver effect," we used liposomes to transfect cultured recipient (Lewis-RT1.Al) hepatocytes with plasmid DNA encoding the soluble donor MHC class I Ag, RT1.Aa. Control or RT1.Aa-transfected hepatocytes were implanted intrasplenically into Lewis recipients 1 day prior to heterotopic ACI (RT1.Aa) heart transplantation and injection of 6 ml of anti-ACI hyperimmune serum (HIS). Results showed that nearly all recipients receiving ACI-specific HIS and control hepatocytes experienced HR, while none of the recipients receiving HIS and hepatocytes expressing soluble RT1.Aa developed HR. Furthermore, active immunosuppression by soluble RT1.Aa was evidenced by prolongation of allograft survival, compared with controls not receiving HIS. In summary, soluble donor-MHC class I Ag gene therapy can prevent antibody-mediated destruction associated with HR. Future development of a similar strategy in humans may significantly improve the results of clinical organ transplantation in immunologically sensitized recipients.

Immunologic suppression mediated by genetically modified hepatocytes expressing secreted allo-MHC class I molecules.

Studies suggest that immunosuppression associated with liver transplantation may be related to the secretion of MHC class I antigen (Ag) by hepatocytes. To investigate this possibility, we developed a culture system whereby naive Lewis (RT1.A1) splenocytes were cocultured with autologous hepatocytes transfected with plasmids encoding either the membrane-bound or secreted allogeneic MHC class I Ag, RT1.Aa. Cytotoxic T lymphocyte (CTL) and helper T lymphocyte (HTL) limiting dilution assays were subsequently performed on preconditioned lymphocytes. Lymphocytes preconditioned with hepatocytes secreting RT1.Aa showed an alloantigen specific inhibition of CTL precursors (CTLp). In contrast, exposure of splenocytes to hepatocyte-expressed membrane-bound RT1.Aa resulted in Ag-specific CTLp priming. This CTLp priming effect by hepatocyte-expressed membrane-bound Ag could be effectively blocked when splenocytes were first preincubated with hepatocytes secreting RT1.Aa, before being exposed to hepatocytes expressing membrane-bound RT1.Aa. In contrast to CTLp, HTLp frequency, as determined by IL-2 production, was unaffected by either hepatocyte-expressed membrane-bound or secreted RT1.Aa. Further studies on splenocytes conditioned with hepatocytes expressing secreted allo-MHC Ag suggest the possibility of suppressor cell development. This was demonstrated by prolongation of ACI (RT1a) heart allograft survival in Lewis recipients following adoptive transfer of splenocytes that were preconditioned in vitro with hepatocytes secreting alloantigen.