Biomedical subjects

H Sozen

Publications and source records attributed to H Sozen.

13 recordsLinked to original sources

PubMed2006

A corner-saving ureteral reimplantation technique without stenting.

In this study we present our new technique, which will simplify reconstruction of even a small-caliber ureter. Our transplantation team has performed 1523 renal transplantation since 1975. From 1975 to 1983, we performed 300 ureteroneocystostomies using the modified Politano-Leadbetter technique. Since 1983, the extravesical Lich-Gregoir technique was used in combination with temporary ureteral stenting in 1141 patients. After September 2003, we began a corner-saving technique. Eighty-two (62 living related, 20 cadaver) renal transplantations have been performed since September 2003. The mean recipient age was 32.2 +/- 10.9 years (range, 7 to 63). Mean donor age was 38.9 +/- 13.1 years. For ureteral reimplantation, a running suture is started from 3 mm ahead from the middle of the posterior wall and finished 3 mm afterward. After the last stitch, both ends of the suture material are pulled and the posterior wall of the ureter and bladder are approximated tightly. The anterior wall is sewn either with the same suture or another running suture. Since using this technique, we have not employed a double J or any other stent to prevent ureteral complications at the anastomosis side. We have seen only two (2.4%) ureteral complications. In conclusion, due to the low complication rate, we believe that our new technique is the safest way to perform a ureteroneocyctostomy.

Adolescent↗

PubMed2006

Expanded criteria for liver transplantation in patients with hepatocellular carcinoma.

INTRODUCTION: Liver transplantation is the only curative treatment for patients with cirrhosis and unresectable hepatocellular carcinoma (HCC) without extrahepatic dissemination. Since criteria for transplantation in HCC are controversial, we evaluated our early results of liver transplantation for unresectable HCC. MATERIALS AND METHODS: Three women and 14 men (age range, 1.1 to 64 years) with preoperatively diagnosed or incidentally discovered HCC underwent liver transplantation. Six grafts were obtained from cadaveric donors, and each of the remaining 11 grafts from a living related donor. Criteria for participation, independent of tumor size and number of tumor nodules, were no invasion of major vascular structure and no evidence of extrahepatic disease. In nine patients, tumors were beyond the Milan criteria. Twelve patients (86.7%) received tacrolimus and 2 (13.30%), rapamycin monotherapy with early withdrawal of corticosteroid therapy. Two patients underwent neoadjuvant chemoembolization before transplantation; none received adjuvant chemotherapy. Seven patients with hepatitis B virus infection underwent antiviral prophylaxis with antibody to hepatitis B surface antigens and lamivudine. RESULTS: During follow-up (range, 1 to 17 months), all patients exhibited excellent graft function. Imaging studies revealed no evidence of tumor recurrence and no elevation of alpha fetoprotein or carcinoembryonic antigen levels. DISCUSSION: Low-dose immunosuppressive therapy and expanded criteria for liver transplantation in patients with HCC, especially when donation from a living related donor is possible, appear to inhibit disease recurrence and improve outcomes.

Adolescent↗

PubMed2005

Liver transplantation and tacrolimus monotherapy for hepatocellular carcinoma with expanded criteria.

Liver transplantation is the only curative treatment option for patients with cirrhosis and unresectable hepatocellular carcinoma (HCC) without extrahepatic dissemination. Criteria for transplantation in HCC are controversial. In this study, we evaluate the early results of liver transplantation for unresectable HCC. Between 2003 and 2004, 10 patients (three woman, seven men; aged 1.1 to 64 years) with occult or incidental HCC underwent liver transplantation. The inclusion criteria (independent of tumor size and number of tumor nodules) were: no invasion of major vascular structures and no evidence of extrahepatic disease, including that based on hilar lymph node biopsy and cytopathological examination of intraperitoneal fluid. Eight patients (80%) received tacrolimus and two patients (20%) received rapamycin monotherapy with early withdrawal of the corticosteroid. Four patients had neoadjuvant chemoembolization before transplantation. None of the patients received adjuvant chemotherapy. Two patients with hepatitis B virus cirrhosis underwent antiviral prophylaxis with anti-HBs antibody and lamivudine. During follow-up (range, 8 to 19 months), all patients did well with excellent graft function. There was no evidence of tumor recurrence on imaging studies, and there were no elevations in alpha fetoprotein or carcinoembryonic antigen levels. Low-dose immunosuppression and expanded criteria for liver transplantation for HCC appear to have beneficial effects on disease recurrence and patient outcomes, especially in regard to living donation.

Adolescent↗

PubMed2005

Living-related liver transplantation in pediatric patients.

INTRODUCTION: Many developments in surgical technique, immunosuppression, and patient selection criteria have led to improved long-term patient and graft survival in pediatric patients receiving liver transplants. In this study, we examined the early results of 26 pediatric recipients who underwent 26 liver transplantations between January 2003 and December 2004 at our institution. MATERIALS AND METHODS: The most common indications for liver transplantation were cholestasis in 10 patients (38.5%) and Wilson's disease in 8 (30.8%). Other indications were fulminant hepatic failure (4 patients, 15.4%), tyrosinemia (2 patients, 7.7%), Caroli disease (1 patient, 3.8%), and cryptogenic cirrhosis (1 patient, 3.8%). One recipient with Byler disease and two with tyrosinemia also had incidental hepatocellular carcinoma. RESULTS: Of 26 patients, 24 (92.3%) underwent living-related liver transplantation and 2 (7.7%) underwent cadaveric transplantation. The medical records of all patients were retrospectively reviewed. Twenty-two of 26 survived with excellent graft function, showing 91.2%, 86.4%, and 81.6% at 3, 12, and 24 months graft and patient survival rates, respectively. Sixteen patients (61.5%) developed various morbidities with biliary and vascular complications being the most common. Four patients (15.3%) developed bile leaks. Four patients (15.3%) developed hepatic artery thromboses. Five patients (19.2%) developed life-threatening infections. Four patients (15.4%) died during the study period, three owing to infectious complications. The other patient died due to acute respiratory distress syndrome. CONCLUSION: Despite technical difficulties and a donor organ shortage, the results of liver transplantation in pediatric patients with end-stage liver disease have demonstrated promising results at our institution.

Adolescent↗

PubMed2005

The effect of graft nephrectomy on long-term graft function and survival in kidney retransplantation.

We retrospectively evaluated the long-term results of 53 (3.5%) recipients who received second allograft among 1486 kidney transplants between November 3, 1975 and June 30, 2004. Two study groups were patients in Group 1 (n = 21) who underwent allograft nephrectomy and those in Group 2 (n = 32) who did not. We assessed demographic features, rejection rates throughout the follow-up period, and serum creatinine levels at 12 months as well as graft and patient survival rates, postoperative complications, time interval between transplantations, and HLA matches. Forty-three patients who underwent retransplantation received kidneys from living-related donors and the remaining 10 from cadaveric donors. Mean serum creatinine levels of Group 1 versus Group 2 were 1.8 mg/dL (range, 0.8 to 6.6 mg/dL) versus 2.1 +/- 1.1 mg/dL (range, 1.1 to 7.1 mg/dL). HLA-AB and HLA-DR mismatches were 1.9 +/- 1.1 versus 1 +/- 0.6, respectively (P = .01). Acute rejection rates were not significantly different between Groups 1 (9/21, 43%) and 2 (12/32, 38%) (P < .05). The average intervals between the first and the second transplantations were 62 +/- 26 months in Group 1 (P = .02) and 32 +/- 11 months in Group 2. One-, 3-, and 5-year graft survival rates in Group 1 versus Group 2 were 83% versus 89% (P > .05); 64% versus 79% (P > .05), and 45% versus 68% (P = .04), respectively. In conclusion, we did not observe any advantage of graft nephrectomy before retransplantation. The length of the interval between the first and the second transplantations may have a negative correlation with second graft survival.

Adolescent↗

PubMed2005

Duct-to-duct biliary anastomosis with a "corner-saving suture" technique in living-related liver transplantation.

OBJECTIVES: Biliary complications after living-related liver transplantation (LRLT) remain a major source of morbidity for recipients. We describe our technique and early results with 32 recipients who underwent LRLT with duct-to-duct anastomoses during the last 2 years. METHODS: Between January 2003 and December 2004, 50 patients underwent liver transplantation in our center with overall patient and graft survival rate of 86.4% and 86.4%. Of 50 patients, 41 (82.0%; 17 adult and 24 pediatric) underwent LRLT, 32 (78.0%) of whom had duct-to-duct biliary anastomoses with a "corner-saving suture" technique. RESULTS: Of 32 patients in whom duct-to-duct biliary anastomoses were performed, 4 (12.5%) had an anastomotic leak with 2 eventually developing bile duct strictures within 3 months. One patient required reoperation for a bile leak. All other anastomotic leaks and strictures were treated with percutaneous drainage and balloon dilatation with excellent outcomes. There was no long-term morbidity and no graft loss owing to biliary complications. Seven patients died during follow-up (0.5 to 25 months); 43 are doing well with optimal liver function in the early posttransplantation period. CONCLUSION: According to our early results, we recommend duct-to-duct anastomosis in LRLT when calibration of the ducts show suitable results and when there is no tension on the anastomosis site. Otherwise, Roux-en-Y hepaticojejunostomy should be performed to decrease risk of biliary complications.

Anastomosis, Surgical↗

PubMed2002

Rapamycin and T cell costimulatory blockade as post-transplant treatment promote fully MHC-mismatched allogeneic bone marrow engraftment under irradiation-free conditioning therapy.

Hematopoietic macrochimerism, established by bone marrow transplantation, can be used as an approach for treating autoimmune disease and inducing transplant tolerance. In this study, we investigated whether a stable, high level of fully MHC-mismatched hematopoietic macrochimerism can be induced by using irradiation-free protocols, and whether rapamycin and T cell costimulatory blockades (anti-CD40L monoclonal antibody (mAb) and CTLA4Ig) as post-transplant treatment promote bone marrow engraftment. Donor-specific blood transfusion (DST), anti-lymphocyte serum (ALS), busulfan, and cyclophosphamide were given pretransplantation. Balb/c (H-2(d)) bone marrow cells, at a dose of 4 x 10(7), were infused into each C57BL/6 mouse (H-2(b)). Rapamycin, anti-CD40L mAb, and CTLA4Ig were then administered, either alone or in combination. Without ALS or busulfan and cyclophosphamide, macrochimerism can only rarely be induced. Donor-specific transfusion (DST) enhances induction of hematopoietic macrochimerism. Rapamycin, anti-CD40L mAb and CTLA4Ig, alone or in combination, induce a stable and high level of hematopoietic macrochimerism. In the chimeric mice, donor-derived cells were detected in all lymphohematopoietic tissues and donor-specific tolerance was induced in vitro. We conclude that a stable and high level of fully MHC-mismatched hematopoietic macrochimerism can be induced in mice after transplanting a single modest dose of bone marrow cells without irradiation. Rapamycin and T cell costimulatory blockade as post-transplant treatment promote bone marrow engraftment.

Animals↗

PubMed2001