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C Radke

Publications and source records attributed to C Radke.

At least 19 recordsLinked to original sources
PubMed2003

Complete bile duct sequestration after liver transplantation, caused by ischemic-type biliary lesions.

Ischemic-type biliary lesions (ITBLs) are the most frequent cause of nonanastomotic biliary strictures in liver grafts, affecting about 2-19 % of patients after liver transplantation. ITBL is characterized by bile duct destruction, subsequent stricture formation, and sequestration. We report here the case of a patient affected by extremely severe ITBL, with sequestration and disintegration of the entire bile duct system, in which it was possible to extract the complete biliary tree endoscopically in a single piece. Histological examination revealed that all cells of the bile duct wall had been destroyed within 3 months after liver transplantation and replaced by connective tissue. Subsequently, biliary stricture formation occurred at the hepatic hilum, as well as the adjacent large bile ducts. It may be hypothesized that cellular rejection of small bile ducts leads to the vanishing bile duct syndrome, whereas cellular rejection of large bile ducts results in ITBL. The strictures were repeatedly dilated by endoscopic means, allowing successful control of stricture formation, as well as maintenance of liver function. At the time of writing, the grafted organ and the patient had survived for more than 3 years in good health. This is the first detailed report on a sequestration of the entire bile duct system caused by ITBL, successfully treated for several years by endoscopic means.

Bile Duct Diseases↗
PubMed2001

Vascular invasion and histopathologic grading determine outcome after liver transplantation for hepatocellular carcinoma in cirrhosis.

Selection of patients suffering from hepatocellular carcinoma (HCC) in cirrhosis for liver transplantation follows limits of number and diameter of tumor nodules. It has not been investigated whether there is a correlation of these parameters with vascular invasion. From 1989 to 2000, 1,188 liver transplantations were performed in 1,087 patients, including 120 patients (11%) with an HCC in cirrhosis. Selection criteria were a maximal diameter of up to 5 cm if the tumor appeared to be uninodular or of up to 3 cm in the case of 2 or 3 nodules. The postoperative mortality rate was 1.7%. One-, 5-, and 10-year survival was 90%, 71%, and 60%, respectively. In 940 transplantation patients without an HCC, these rates were 93%, 87%, and 83% (P < .0001). Vascular invasion and histopathologic grading were identified as prognostic parameters by multivariate analysis. In a logistic regression analysis, histopathologic grading and maximal diameter showed a significant correlation with a vascular invasion. Analyzing tumors larger than 5 cm, i.e., tumors not fulfilling the selection criteria as a result of diagnostic inaccuracy or progression thereafter, the rates of vascular invasion were significantly (P < .01) lower in patients suffering from well-differentiated tumors (25%) when compared with moderately and poorly differentiated tumors (100%). Liver transplantation is a safe and effective long-term treatment for small HCC in cirrhosis. Tumor diameter and number of nodules in correlation with the histopathologic grading were predictive of a vascular invasion only in HCC larger than 5 cm.

Adult↗
PubMed2001

Occurrence and clinical outcome of lamivudine-resistant hepatitis B infection after liver transplantation.

Lamivudine treatment of hepatitis B after orthotopic liver transplantation (OLT) is often accompanied by fast viral-resistance formation. Although no clinical data are available, in vitro data indicate that lamivudine-resistant reinfection has a mild course because of defective viral replication. Between 1996 and 1999, a total of 34 patients were treated with lamivudine because of hepatitis B recurrence after OLT. All patients developed reinfection despite long-term passive immunoprophylaxis with hepatitis B immunoglobulin, diagnosed by positive hepatitis B surface antigen and positive hepatitis B virus (HBV) DNA. Before treatment with lamivudine, 21 of these patients underwent a course of famciclovir and developed resistance. Monthly laboratory tests and sequential liver biopsies were performed during the follow-up period. Nineteen of 34 patients (56%) developed lamivudine resistance during the follow-up period of 12 to 49 months. One- and 3-year graft survival rates after the diagnosis of lamivudine resistance were 89% and 66%, respectively. In most cases, lamivudine resistance was associated with high viral replication (3,012 +/- 574 pg/mL 1 month after the diagnosis of lamivudine resistance); however, liver enzyme levels were only moderately elevated (alanine aminotransferase [ALT], 45 +/- 16 U/L). Only 3 patients (15%) showed a rapid increase in ALT level to more than 500 U/L within 3 months after resistance developed. All other patients had mildly elevated liver enzyme levels during the first 6 to 8 months after lamivudine resistance. In the later course, liver enzyme levels increased in most patients. Fourteen patients with elevated transaminase levels were switched to lamivudine plus interferon alfa (n = 8) or lamivudine plus famciclovir therapy (n = 6). This combination was successful in most cases, decreasing HBV DNA and liver enzyme levels. Four patients with lamivudine resistance died during follow-up, only 1 patient because of HBV reinfection. In addition, 2 patients underwent retransplantation because of hepatitis B cirrhosis of the first graft. Compared with historic courses of wild-type recurrence, lamivudine-resistant reinfection is characterized by a milder clinical course. Fulminant cases were not observed; however, in three cases, chronic liver failure developed. The combination of different antivirals diminished viral replication after lamivudine resistance. In the future, new antiviral agents, such as adefovir, might further expand therapeutic options.

Drug Resistance, Microbial↗
PubMed2000

Quadruple tacrolimus-based induction therapy including azathioprine and ALG does not significantly improve outcome after liver transplantation when compared with standard induction with tacrolimus and steroids: results of a prospective, randomized trial.

BACKGROUND: Tacrolimus in combination with prednisolone has been proven to be a safe and effective immunosuppressive induction therapy in solid organ transplantation. However, it remains unclear whether a tacrolimus-based quadruple induction regimen with azathioprine and an antilymphocytic preparation could further improve the results after orthotopic liver transplantation. Therefore, we designed a prospective, randomized study to compare the immunosuppressive efficacy of dual (tacrolimus and prednisolone) and quadruple (tacrolimus, azathioprine, ALG Merieux and prednisolone) induction after liver transplantation. METHODS: After randomization, 120 consecutive patients of primary liver transplants were divided into the dual group (n=59) and the quadruple group (n=61) and followed for a minimum of 3 years. RESULTS: Patient survival at 3 years was 88.2% in the dual versus 94.9% in the quadruple group. Overall 25 patients in each group (41 and 42%, respectively) developed acute rejection. There was no difference in the number and severity of rejections. In each group only four patients required OKT3-therapy, however, although three of four patients in the quadruple group responded to OKT3 and cleared rejection, none of the four patients in the dual group were treated successfully with OKT3 (P<0.02). Rejection in these patients resolved only after additional treatment with mycophenolate mofetil. Adverse events and infections were equally distributed in both groups. Asymptomatic Cytomegalovirus infections were more common in the quadruple group (P<0.02). As of today, only one patient developed posttransplant lymphoproliferative disease (dual group). CONCLUSIONS: The data from our single-center study indicate that both tacrolimus-based dual and quadruple immunosuppressive induction regimens yield similar safety and effectiveness after liver transplantation.

Adult↗
PubMed2000

[Protection of autogenous cartilage transplants from resorption using membrane encapsulation].

In reconstruction of cartilage defects, autogenous transplantation is known as a reliable and experienced method. Although a clinical application has not been reported until now, tissue engineering permits in vitro production of autogenous cartilage transplants. Nevertheless, in both methods the cartilage is exposed to individually varying resorptive mechanisms. Among other methods for in vivo tissue protection, the encapsulation with a semipermeable polyelectrolytecomplex membrane could guarantee sufficient protection against resorptive influences. Human septal cartilage was encapsulated (group 1) with polyelectrolytecomplex membranes and subcutaneously implanted on the back of thymusaplastic nude mice. Cartilage implants without encapsulation (group 2) were used as control. Scanning electron microscopy and histochemical investigations were performed 1, 4, 8, 12 and 16 weeks after implantation. Group 1 showed no signs of resorption and chronic inflammation at all. In contrast, group 2 presented, correlating to the time of implanta-tion, increasing signs of cell death and fibrotic transformation, representing an increased activity of resorption. In conclusion, tissue encapsulation with a polyelectrolytecomplex membrane could ensure a sufficient protection of human cartilage transplants from resorptive influences. For the plastic-reconstructive surgeon the desired result becomes more calculable.

Animals↗
PubMed2000

Primary and secondary hepatic manifestation of neuroendocrine tumors.

BACKGROUND: In comparison with most other malignancies, in the treatment of metastatic neuroendocrine tumors one also has to consider endocrine symptoms and natural progression of disease. Since hepatic metastasis predominates and endocrine symptoms correlate with functional tumor mass, hepatic resection may improve prognosis or even cure patients. PATIENTS AND METHODS: We reviewed 41 consecutive patients with metastatic neuroendocrine tumors and four patients with primary hepatic disease presenting between 1989 and 1999. The neuroendocrine tumors were classified according to their origin, pattern of metastasis, endocrine activity, and histology. Operative therapy including hepatic resections of different extent, liver transplantation, and removal of the primary tumor was analyzed. The median survival after initial diagnosis and after hepatic resection were major parameters of outcome. RESULTS: There were 26 low-grade malignant, 12 high-grade malignant, 2 biphasically differentiated neuroendocrine carcinomas, and 5 pancreatic endocrine tumors. Hepatic resections were performed in 25 patients, resections of the primary tumor in 40 patients. The median survival after initial diagnosis was 49 months; 50.5 months in patients with hepatic resection versus 47 months in those with no liver surgery. CONCLUSION: Hepatic resection improved the outcome of patients with liver metastasis due to neuroendocrine tumors tendentiously but not significantly.

Adult↗
PubMed2000

Macroencapsulation of human cartilage implants: pilot study with polyelectrolyte complex membrane encapsulation.

Autogenous cartilage transplantation is a generally accepted method in reconstructive surgery. A promising alternative to this established method could be represented by in vitro engineering of cartilage tissue. In both methods of autogenous transplantation, host response induces reduction of transplant size and transplant instability to an unforeseeable extent. To investigate if polyelectrolyte complex (PEC) membranes were able to avoid host-induced effects on implanted tissues without neglecting the tissue metabolism, human septal cartilage was encapsulated with polyelectrolyte complex membranes and subcutaneously implanted on the back of nude mice. Septal cartilage implants, without encapsulation served as control group. Histochemical and electron microscopic investigations were performed 1, 4, 8 and 16 weeks after implantation. In the case of an intact PEC-membrane no interactions between the host and the implant could be observed. In some implants, the capsule was torn in several areas and signs of chronic inflammation with the cartilage having been affected mildly could be observed. Implanted cartilage protected with PEC-encapsulation showed no signs of degeneration and significantly lower level of after effects of chronic inflammation than implanted cartilage without PEC-encapsulation. Therefore, it could be expected, that PEC membrane encapsulation offers a novel approach to protect cartilage implants from host response after autogenous transplantation.

Animals↗
PubMed1999

Hepatocytes are permissive for human cytomegalovirus infection in human liver cell culture and In vivo.

The cytopathic potential of human cytomegalovirus (HCMV) in human liver cells was analyzed in cell culture and in tissue sections from patients with HCMV hepatitis. Liver cell cultures, consisting of hepatocytes, bile duct epithelial cells, and stromal cells were infected by various HCMV strains. Cytopathic effects, viral gene expression, and virus production were detected. Infected cell types were identified by immunocytochemical double labeling. Hepatocytes were the predominant target cells of HCMV infection in liver tissues and in cell culture. Late-stage infected cultured hepatocytes produced infectious progeny virus, and infectious virus was propagated from liver tissue specimens. HCMV infection in cultured liver cells closely resembled in vivo infection of the liver with regard to the target cell spectrum and the permissive course of infection. It is concluded that HCMV can cause direct liver parenchyma damage by efficient cytolytic infection of hepatocytes.

Antigens, Viral↗
PubMed1999

Extended resections for hilar cholangiocarcinoma.

OBJECTIVE: To evaluate different strategies for extended resections of hilar cholangiocarcinomas on radicality and survival. SUMMARY BACKGROUND DATA: Surgical resection of hilar cholangiocarcinoma is the only potentially curative treatment. Resection of central bile duct carcinomas, however, cannot always comply with the general principles of surgical oncology to achieve wide tumor-free margins with no-touch techniques. METHODS: From 1988 to 1998, 95 patients underwent resection of hilar cholangiocarcinoma. Eighty patients had hilar and hepatic resections and 15 had liver transplantation and partial pancreatoduodenectomy (LTPP; i.e., eradication of the entire biliary tract using a no-touch technique). RESULTS: The 60-day death rate was 8%. The overall 1- and 5-year survival rates were 67% and 22%, respectively. Five-year survival rates after R0, R1, and R2 resections were 37%, 9%, and 0%. In a multivariate analysis, surgical radicality was the strongest determinant of survival (p < 0.001). The rate of formally curative resection (R0 resection) was significantly lower in hilar resections (29%) than in liver resections (left hemihepatectomy 59%, right hemihepatectomy 55%, right trisegmentectomy 65%; p < 0.05). The highest rate of R0 resection was observed after LTPP (93%; p < 0.05). Right trisegmentectomies achieved the highest rate of 5-year survival after R0 resection (57%). In a multivariate analysis of patient survival after R0 resection, additional portal vein resection was the only significant factor. The 5-year survival rate after formally curative liver resection with portal vein resection was 65% versus 28% without. CONCLUSION: Extended resections, especially right trisegmentectomies and LTPP, resulted in the highest rate of R0 resection. Right trisegmentectomy together with portal vein resection best represents the principles of surgical oncology and may be regarded as the surgical procedure of choice. Immunosuppression limits the applicability of LTPP.

Aged↗