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Y Tokat

Publications and source records attributed to Y Tokat.

At least 19 recordsLinked to original sources
PubMed2006

The prevention of bone fractures after liver transplantation: experience with alendronate treatment.

OBJECTIVE: The aim of this study was to prevent fractures in the first postoperative year. METHODS AND PATIENTS: We studied 59 patients (48 men, 11 women) aged 42.6+/-11.4 years, who underwent liver transplantation. All patients received oral alendronate 70 mg weekly and calcium 1 g and calcitriol 0.5 mug daily. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the lumbar spine and proximal femur at baseline as well as at 6 and 12 months after transplantation for comparison with an historical control group (n=31). Spinal radiographs were obtained to assess vertebral fractures at the same time. Additionally, serum osteocalcin, serum parathyroid hormone (PTH), urinary deoxypyridinoline (DPD), and biochemical parameters were determined every 3 months. RESULTS: At baseline, femoral total BMD of men was significantly greater than that of women (P<.05, .85+/-.1 vs .74+/-.1). A significant increase in BMD was observed at 12 months (P<.05), no patient developed a bone fracture. Comparison analysis of genders showed that there was a significant difference in favor of men (P<.05). The lumbar BMD, neck T-, and Z-scores were significantly higher among patients treated with alendronate than historical controls (P<.05). After 3 months, serum PTH was increased and serum osteocalcin and urinary DPD were reduced. No severe side effects from alendronate treatment were observed during the study. CONCLUSION: A direct sign of the success of our study was no fracture observed during the first postoperative year. Alendronate should be considered for patients with low bone mass after liver transplantation.

Adult↗
PubMed2006

Hepatocellular carcinoma in children and effect of living-donor liver transplantation on outcome.

Hepatocellular carcinoma (HCC) is primarily observed in the older children and in most cases it develops in association with liver cirrhosis. Liver transplantation offers a good chance for long-term cure. To evaluate the outcome of children with HCC and the impact of living-donor orthotopic liver transplantation (OLT) on survival a retrospective review of radiographic, laboratory, pathologic, and therapeutic data in 13 children (six female and seven male) with chronic liver disease accompanied with HCC were studied. The patients were divided into two groups according to therapeutic modality: transplanted and non-transplanted patients. Kaplan-Meier survival curves in various therapeutic groups were plotted. The mean age of patients was 6.4 +/- 4.8 yr. Pediatric end-stage liver disease score was adapted to model for end-stage liver disease score for HCC and ranged between 1-44 and 18-44, respectively. The underlying liver diseases were tyrosinemia type 1 (n = 6), chronic hepatitis B infection (n = 6), glycogen storage disease type 1 (n = 1). Alfa-feto protein levels were elevated in all patients except one. Median number of tumor nodules was three (1-10), median maximal diameter of tumor nodules was 3.4 cm (0.5-8). Eleven patients were eligible for OLT whereas two patients were not eligible. Seven of the 11 patients considered for transplantation underwent living-donor OLT. Remaining four patients died while waiting on cadaveric transplant list. Overall 1 and 4-yr survival rates for all patients were 53.3 and 26.6%, respectively, and were found significantly higher in transplanted children than non-transplanted children (72%, 72% vs. 33% and 16.6%). No patient had tumor recurrence at median of 36-month follow-up after OLT. OLT is a life-saving procedure for children with chronic liver disease accompanying with HCC. Living-donor OLT avoids the risk of tumor progression and transplant ineligibility in these children.

Adolescent↗
PubMed2005

Successful treatment of liver transplant-associated Kaposi's sarcoma with long-term vincristine.

Kaposi's sarcoma has a higher incidence in organ transplant recipients. We report on a 41-year-old Turkish man with liver transplantation-associated Kaposi's sarcoma that involved the skin and the gut. Immediately after discontinuation of immunosuppressive medication, there was an acute rejection episode. After controlling the acute rejection with steroids, the immunosuppressive treatment was continued together with vincristine, which resulted in disease remission. After 6 months, withdrawal of vincristine lead to relapse of the disease, prompting commencement of vincristine again, which has maintained the patient in remission for more than 3 years without any significant side effects. In conclusion, long-term vincristine may be an effective, safe treatment option for Kaposi's sarcoma.

Adult↗
PubMed2005

HBV vaccination in liver transplant recipients: not an effective strategy in the prophylaxis of HBV recurrence.

Anti-HBs immunoglobulins (HBIG) and lamivudine are main options to prevent hepatitis B virus (HBV) reinfection after liver transplantation. Although they are very effective, development of mutant viruses and high cost of treatment are main limitations for their application. Additionally there is an uncertainity for the duration of that prophylaxis regimen and its mostly applied indefinitely. Recently, post-transplant HBV vaccination is reported to be a cheaper alternative prophylaksis strategy, that enables discontinuation of HBIG. To investigate the efficacy of HBV vaccination in patients transplanted for HBV cirrhosis, we administered double course of double dose recombinant HBV vaccine (Genhavac B; containing HBV pre-S1, pre-S2, and S gene products). Vaccination has been started 1 month after HBIg discontinuation, and lamivudine (100 mg/day) was given throughout the study. The first cycle consisted of 0, 1- and 6-month schedule, and, in nonresponders, second cycle 0, 1-, 2-month schedule. Fourteen patients included into the study. Only one patient seroconverted (an anti-HBs titre of 37 IU/L) after the first cycle. No other patient responded to second cycle. HBV vaccination in the post-transplantation setting does not seems like an effective strategy in the prophylaxis of HBV recurrence.

Adult↗
PubMed2005

Outcome of pediatric liver transplant recipients in Turkey: single center experience.

To summarize the evolution of the pediatric liver transplant program in a developing country. Between April 1997, and September 2003, 32 cadaveric (CD) and 35 living donor (LD) liver transplantations were performed on 61 children (median age 3.8 yr, range 0.5-16) at Ege University Organ Transplantation and Research Center. The patient's charts were reviewed retrospectively. The outcome of patient and graft survival was analyzed and the incidence of graft loss, complications and rejections was calculated. Indications for liver transplantation were metabolic liver disease (n = 17), biliary atresia (n = 14), viral hepatitis (n = 4), autoimmune hepatitis (n = 6), cryptogenic cirrhosis (n = 11), fulminant liver failure (n = 5) and others (n = 5). Seven of 61 children with chronic liver disease had hepatocellular carcinoma concomitantly. Median pediatric end-stage liver disease score was 23 (range 1-54). Seven children (11.4%) were UNOS status I, 44 (72%) were UNOS status II and 10 (16.6%) were UNOS status III. The median follow-up of the study population was 3.6 yr (range 0.5-6). Actuarial patient survival rates at 1, 2, 3 and 4 yr were 86, 86, 71.3 and 65% in the CD group vs. 80, 76, 67 and 67% in the LR group, respectively (p = NS). Patients listed as UNOS status 1 had lower survival rates than patients listed as UNOS status 2 and 3 (p < 0.05). The mortality rate was 26.2%. Graft survival rates were 81, 81, 75 and 64% at 1, 2, 3 and 4-yr respectively. Six patients (9%) underwent retransplantation. The main complications were infections (64.7%) and surgical complications (43.2%) (including biliary complication, vascular problems, postoperative bleeding, small for size and large for size). The incidence of acute cellular rejection was 39.3%, whereas chronic rejection was 7.4%. The result of liver transplantation in Turkish children was slightly inferior to those reported for North American and European children. However, an important characteristic of these patients that distinguishes them from Europe and North America is that most were UNOS status IIa and UNOS status I (44%). Despite technical and medical progress, infectious and biliary problems have continued to be an important cause of mortality in these patients.

Adolescent↗
PubMed2004

Impact of pretransplant MELD score on posttransplant outcome in living donor liver transplantation.

It is not clear whether pretransplantation MELD (model for End-Stage Liver Disease) score can foresee posttransplant outcome. We retrospectively evaluated 80 adult patients (55 men, 25 women) who underwent living donor liver transplantation between September 1998 and March 2003. Five other patients with fulminant hepatitis were excluded. The UNOS-modified MELD scores were calculated to stratify patients into three groups: group 1) MELD score less than 15 (n = 13); group 2) MELD score 15 to 24 (n = 36); and group 3) MELD score 25 and higher (n = 26). The patients were predominantly men (n = 52, 69.3%) with overall mean age of 43.9 years (range, 17-62 years). The mean follow-up was 15.7 months (range, 1-47; median = 14 months). The mean MELD score was 22.7 (range, 9-50; median = 21). The overall 1- and 2-year patient survivals were 87% and 78.7%, respectively. The 1-year patient survivals for groups 1, 2, and 3 were 100%, 87%, and 79%; respectively. 2-year survivals, 100%, 79%, and 61%, respectively. Survivals stratified by MELD showed no statistically remarkable differences in 1-year and 2-year patient survival (P = .08). In contrast, 1-year and 2-year patient survival rates for UNOS status 2A, 2B, and 3 were 73%-50%, 95%-91%, and 91%-91%, statistically significant difference (P = .002). Finally, to date preoperative MELD score showed no significant impact on 1- and 2-year posttransplant outcomes in adult-to-adult living donor liver transplantation recipients, but we await longer-term follow-up with greater numbers of patients.

Adolescent↗
PubMed2004

Rituximab therapy for life-threatining immune hemolytic anemia in a liver tranplant recipient: a case report.

Rituximab an anti-CD20 chimeric monoclonal antibody directed against the CD20 antigen on B lymphocytes, has been demonstrated to be highly effective for B-cell depletion. Because of its biological properties, it has become as a treatment option for a variety of autoimmune diseases. We report successful treatment of a 25-year-old male cadaveric liver retransplant recipient who displayed severe immune hemolytic anemia with rituximab, despite no previous response to corticosteroids plus intravenous immune globulin therapy.

Adult↗
PubMed2004

Adefovir treatment in posttransplant hepatitis B virus infection resistant to lamivudine plus hepatitis B virus immunoglobulin.

Failure of prophylaxis for hepatitis B virus (HBV) recurrence in liver transplant patients with HBV immunoglobulin (HBIG) or lamivudine or both can be associated with rapid development of liver failure. Some of these patients develop a devastating clinicopathological state characterized by jaundice and rapidly progressive liver failure or fibrosing cholestatic hepatitis. We present two liver transplant recipients who experienced HBV recurrence while they were under lamivudine and HBIG prophylaxis. One of them had finding of severe HBV infection; the other, fibrosing cholestatic hepatitis. After commencing adefovir dipivoxil both patients showed improvements in clinical status and laboratory data. At month 4 of treatment, HBV DNA values became negative and liver function tests almost normalized. In addition, in one case showed HBs ag/anti-HBs seroconversion. When failure of prophylaxis with lamivudine and HBIG occurs, adefovir dipivoxil should be considered to be a safe and effective choice for recurrent HBV infections in liver transplant patients.

Adenine↗
PubMed2004

Variations of hepatic veins: helical computerized tomography experience in 100 consecutive living liver donors with emphasis on right lobe.

Anatomical variations in the venous system of liver are not a rarity. A prospective helical computerized tomography (CT) study was undertaken to determine the prevalence of surgically significant hepatic venous anatomic variations among 100 consecutive living liver donors. The studies evaluated the ramification pattern of hepatic veins, the presence of accessory hepatic veins, and of segment 5 or 8 veins (or both) draining into middle hepatic vein. These data obtained by CT influenced surgical planning. Sixty-four donors donated their right lobes and 24 donors, left lateral segments. Only one donor candidate was refused due to combined hepatic and portal venous variations accompanied by multiple bile ducts. Eleven donors were also refused due to reasons other than anatomical variations. Seventeen segment 5 and 17 segment 8 veins draining into middle hepatic vein were anastomosed to inferior vena cava in 23 (36%) of the right lobe liver transplantations. The middle hepatic vein was harvested in only one of the donors. Among the 100 cases, 47 had accessory right inferior hepatic veins, 13 of which were multiple. Twenty-two of the right lobe grafts required surgical anastomoses of these accessory hepatic veins (34%). An isolated hepatic vein anomaly or the presence of accessory hepatic veins are not contraindications to be a living liver donor candidate. However, preoperative knowledge of vascular variations alters surgical management. Helical CT is a valuable tool to delineate the hepatic venous anatomy for surgical planning in living liver donors.

Adult↗
PubMed2004

Cytokine gene polymorphism and early graft rejection in liver transplant recipients.

Cytokines, which play important roles in allograft rejection, show variable production among individuals. These variations may be related to genetic polymorphisms within the regulatory regions of the cytokine genes. We investigated the association between the role tumor necrosis factor alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), interferon gamma (IFN-gamma), interleukin (IL)-10 and IL-6 gene polymorphisms and early graft rejection among liver transplant recipients. Forty-three liver transplant recipients enrolled in this study were divided into 2 groups based on events in the first 2 months posttransplantations, namely, those experiencing at least 1 rejection episode (n = 26) or those without any episode (n = 17). The allele or genotype frequencies of cytokine gene polymorphisms showed no difference between liver recipients with or without nonrejection. In conclusion, there was no significant correlation between early graft rejection and cytokine gene polymorphism of TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma in liver transplant recipients.

Adolescent↗
PubMed2003

Allergic disease after pediatric liver transplantation with systemic tacrolimus and cyclosporine a therapy.

Cyclosporine A (CsA) and tacrolimus (Tac), both calcineurin inhibitors, have been used extensively for immunosuppressive therapy in pediatric liver transplant recipients. They share a similar mechanism of action, the inhibition of cytokine gene transcription primarily interleukin-2 (IL-2) in T lymphocytes. Despite the strong immunosuppressive property, there are several reports of food allergy in pediatric transplant recipients under Tac immunosuppression, but not CsA. In this paper we report on 3 of 50 pediatric liver transplant recipients diagnosed with food allergy and asthma while receiving systemic Tac/CsA immunosuppression and the discuss the role of calcineurin inhibitors in this situation.

Adolescent↗
PubMed2003

Liver transplantation in a patient with Budd-Chiari syndrome secondary to factor V Leiden mutation.

A point mutation in the factor V Leiden gene is the most common hereditary thrombophilic state and an important risk factor for Budd-Chiari syndrome. We report on a patient with Budd-Chiari syndrome secondary to factor V Leiden mutation, who underwent successful liver transplantation. Following liver transplantation, his thrombophilic state was corrected and he did not require anticoagulation therapy. There has been no recurrent venous thrombosis for 14 months after transplantation. Although his activated protein C sensitivity was normal, showing the normalization of protein C-factor V interaction, PCR analysis demonstrated that heterozygosity for factor V Leiden mutation was still present. We suggest checking resistance to activated protein C, rather than PCR analysis of factor V Leiden mutation in patients with Budd-Chiari syndrome after liver transplantation; the presence of the second does not effect clinical outcome.

Blood Coagulation↗
PubMed2003

Hepatocellular carcinoma in liver transplant era: a clinicopathologic analysis.

Hepatocellular carcinoma (HCC) is one of the most common tumors in the world, and the prognosis is usually poor. Today, liver transplantation (LT) is a radical but frequently curative treatment modality for HCC. In selected patients, it cures HCC and the underlying cirrhosis at the same time. The present clinicopathological study examined the importance of tumor characteristics for their effects on recurrence and survival rates after LT for HCC. Forty-two native hepatectomy specimens among 250 consecutive orthotopic liver transplantations contained HCC. Patients were predominantly men (30 men, 12 women), ranging in age from 1 to 61 years (median 51). While 20 patients received cadaveric organs, 22 were transplanted from living donors. In 14 patients (33%) HCC presented as a solitary nodule, 5 (12%) as two nodules; 2 (5%) as three nodules; and 21 patients (50%) as more than three nodules. The maximal diameter of the largest tumor not larger than 3 cm in 28 patients (66%), exceeding this size in 14 patients (34%). There was a significant correlation between nodule number and tumor size (r = 0.36, P = 0.05). While 23 patients had no sign of vascular involvement, 17 tumors showed microscopic invasion and two large vessel involvement. There was a positive correlation between vascular invasion and nodule number (r = 0.41, P = 0.05). The histopathological grade of differentiation of the tumors was assessed as "well" in seven patients (14%), moderate in 28 (72%), and poor in 7 (14%). The differentiation was significantly poorer when vascular invasion was observed (r = 0.43, P =.01). According to the TNM classification, 11 patients (26%) were stage I, 6 (14%) stage II, 13 (31%) stage III, and 12 (29%) stage IV. After a median follow-up of 10 months (1-50 months), the overall mortality was 18% (n = 8). Patient survival at 6 month, 1, and 4 years was 88%, 80%, and 60%, respectively. The outcome was significantly poorer for TNM stage IV versus stage I,II, and III tumors to (P =.02). Tumor recurred in three patients at 4,6, and 50 months after liver transplantation. The sites of recurrence were bone, lung, and adrenal glands. In conclusion, liver transplantation represents a safe and feasible treatment for hepatocellular carcinoma with excellent outcomes compared with other treatment modalities. Liver transplantation offers excellent survival rates and chance for cure in stages I, II, and III hepatocellular carcinoma in cirrhotic patients.

Adolescent↗
PubMed2003

Anesthetic management and complications in living donor hepatectomy.

A total of 112 living donor hepatectomies (LDHs) performed from October 1999 to April 2003 at Ege University Hospital Organ Transplantation Center were reviewed and perioperative anesthetic courses and complications were determined. There was no perioperative mortality. Mean duration of operations was 333 +/- 77 minutes (range, 160 to 540 minutes) for right lobectomies and 277 +/- 88 minutes (range, 150 to 500 minutes) for left lateral segment plus left lobe operations. The remnant liver volume ratios of the patients was 0.58 +/- 0.16 (range, 0.30 to 0.91) after harvesting. Crystalloids, colloid infusions, and transfusions aimed to keep hematocrit >25%, central venous pressure (CVP) <5 mm Hg and to maintain a urine output >1 mL/kg(-1) while nitroglycerin was infused (0.5 to 2.0 microg/kg(-1)h(-1)) when needed to allow fluid infusions freely without increasing the CVP values. No transfusion was needed for 91 patients (81%) and 21 right lobectomy patients needed transfusion of blood products. Initial mean hematocrit of 38.9 +/- 4.9% (range, 27% to 50%) for all patients was found 31.5% +/- 5% (21% to 44%) at the end of the operation. Albumin blood levels averaged 4.27 +/- 0.49 g/dL(-1) at the beginning and 3.28 +/- 0.45 g/dL(-1) after hepatic resection. Perioperative complications were one air embolism, postoperative systemic inflammatory response syndrome in one patient, transient but severe hemoglobinuria due to a predonated autologous blood transfusion in another, prolonged recovery for neuromuscular blocker overdose in one patient, and postoperative atelectasis in three patients, two of whom had pneumonia later while two other patients had pleural effusions. One required a drainage. Living donor hepatectomies were performed with acceptable complications in anesthetic management during this study. The operation provides us with an optimal liver segment without resulting in mortality.

Anesthesia↗
PubMed2003

Causes of postreperfusion syndrome in living or cadaveric donor liver transplantations.

OBJECTIVE: The postreperfusion syndrome (PRS) occurrence was evaluated in patients undergoing liver transplantation in our institution to determine the relationship between PRS and associated variables. METHODS: Of the 185 consecutive liver transplants, pediatric patients, patients with uncompleted data or retransplantations were excluded. The remaining 145 adult patients having 77 cadaveric and 68 living donor right lobe liver transplantations were studied. PRS was defined as a decrease in mean arterial pressure >30% below the baseline value. Logistic regression was used for statistical analyses. A P value <.05 was considered as significant. RESULTS: Total rate of PRS occurrence was 48.9% (71 patients) for the 145 patients. Logistic regression analyses revealed a significant relationship between the PRS and four of the variables: shorter duration of the anhepatic period, higher mean calcium requirement, higher mean heart rate difference from anhepatic to reperfusion period and lower central venous pressure at the dissection period during operations (P <.05). We could not demonstrate any significant effect of the operation type-surgical technique and duration of operations, blood and fresh frozen plasma volume transfused, demographic variables of the recipients, donor liver factors, other haemodynamic and metabolic variables at specific time periods (P >.05). CONCLUSIONS: In conclusion, it is important that PRS does not seem to occur in a predictable manner in this study except for the increased calcium requirements during the operations in PRS experienced patients. The clinical parameters as graft ischemia time, the type of the operation, demographic variables of the recipient, hemodynamic or metabolic variables and transfusion needs during the operations seemed to have no contribution to PRS occurrence.

Adult↗
PubMed2003

Roux-en-Y bleeding after living donor liver transplantation: a novel technique for surgical treatment.

Upper gastrointestinal bleeding (GIB) is one of the most common gastroenterologic complications following liver transplantation. The aim of this study is to define the prevalence of GIB due to Roux- en Y (R-Y) enteral anastomoses after living donor liver transplantation (LDLT) and recommend an anastomotic technique for easy surgical intervention. Ninety-five patients underwent 96 LDLT from June 1999 through January 2003. R-Y biliary reconstruction was employed in 43 patients. Anastomoses were end-to-side (ES) in the first 25 patients and side-to-side (SS) type in the last 18 patients. GIB occurred in 13 patients (30%). The R-Y anastomotic line was shown to be the bleeding site in 10 patients. Anastomoses were in ES fashion in 7 of 10 patients (70%). In other words 28% of ES and 17% of SS anastomoses displayed a bleeding episode after LDLT. Four patients required surgical intervention (Three ES, one SS), namely an operative rate of 9%. The type of the jejunojejunostomy, the UNOS or Child-Pugh scores, the presence of preexisting portal hypertension, the duration of portal vein clamping, the GRWR of patients, revealed no statistical significant difference between bleeding and non- bleeding patients. Although statistical analyses did not reveal any significant difference (P =.47), GIB was higher among patients with an ES type of anastomoses. As a result we recommend a jejunojejunostomy in SS fashion on the antimesenteric borders of the jejunal segments with a 3-4 cm blind intestinal segment. The surgical procedure for R-Y bleeding may then be performed without disrupting the jejunojejunostomy.

Anastomosis, Roux-en-Y↗
PubMed2003

Hemophagocytic syndrome after living-related liver transplantation.

Hemophagocytic syndrome (HPS) is a life-threatening hematological disorder in immunocompromised patients. Although the number of patients with HPS following liver transplantation is scarce the outcome is usually fatal. We report a patient who developed HPS following living-related liver transplantation (LRLT) and was treated successfully by a combination of intravenous (IV) immunoglobulin (Ig) and granulocyte colony-stimulating factor (GCSF).

Adult↗