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M Kalayoglu

Publications and source records attributed to M Kalayoglu.

At least 37 records · Page 2Linked to original sources

Determinants of graft survival after renal transplantation.

We studied multiple determinants of graft survival at a single center and the effects of nonimmunologic graft loss on transplant survival. This retrospective study examined the results of 589 cadaver donor transplants performed between 1986 and 1992. Graft survival rates were calculated using Kaplan-Meier estimates for both overall graft survival (all causes of graft loss) and immunologic graft survival (function lost due to acute or chronic rejection and noncompliance). Cadaver graft survival was significantly poorer with an increasing degree of DR mismatch (P=0.02). An analysis of pretransplant variables showed graft loss risk was highest with greater DR mismatches, two B-antigen mismatch, higher donor serum creatinine, and younger recipient age. After transplantation, acute rejection was the most significant factor associated with long-term graft survival. Our data demonstrate a significant advantage for zero DR and one DR mismatch cadaver donor transplants, with excellent immunologic graft survival. This study suggests that a combination of immediate graft function, prevention of acute rejection by appropriate early immunosuppressive therapy, and acceptable DR match enhances cadaveric graft survival.

Adult↗

Impact of improving immunosuppressive treatment on outcome in cadaveric kidney transplantation.

BACKGROUND: Since the advent of cyclosporine-based immunosuppression for cadaveric kidney transplants in 1983, several changes have been made in immunosuppressive management at the University of Wisconsin. Since 1986, OKT3 has been available to treat steroid-resistant rejection; since 1992, OKT3 has been used as an induction agent replacing antilymphocyte globulin; and since 1993, mycophenolate mofetil has been used in 104 patients. METHODS: The impact of different immunosuppressive strategies on overall and immunologic graft survival (defined as graft loss caused by rejection) was evaluated in 1210 primary cadaveric renal transplants at the University of Wisconsin. Covariables, including degree of human leukocyte antigen matching, age, gender, cause of kidney failure, and early graft dysfunction, were evaluated. The series was subdivided into four eras according to immunosuppressive regimen, and the results were analyzed by era. RESULTS: Our principal findings are that immunologic graft survival has improved significantly during this series whereas overall graft survival has not. Mycophenolate was associated with a significant decrease in acute rejection. For a given patient, graft loss from rejection becomes less likely over time. Late rejection poses a greater risk than early rejection for graft loss. CONCLUSIONS: Improving outcomes may be related to improving immunosuppressive treatment, increasing degree of human leukocyte antigen matching, and better early graft function.

Adult↗

Risk factors for renal allograft loss in patients with systemic lupus erythematosus.

Controversy exists regarding the risk factors for renal allograft loss in patients with systemic lupus erythematosus (SLE). This study is a retrospective evaluation of each of these independent risk factors in 80 renal transplants for ESRD secondary to SLE done at our institution between 1971 and 1994. Our entire non-diabetic cohort of 1,966 renal transplants is used as a comparison group. Our results showed equivalent graft survival rates between lupus patients and the cohort at 1, 5 and 10 years (P = 0.56). However, an analysis of cyclosporine-era cadaver grafts revealed that the lupus group had poorer 5-year graft survival than the cohort (41% vs. 71%, P = 0.02). Evaluation of cyclosporine-era lupus graft survival showed significantly improved outcome in living-related lupus recipients over cadaver grafts at five years (89% vs. 41%, P = 0.003). The majority of grafts lost in the lupus cadaver recipients were due to chronic rejection. Rejection was increased in lupus recipients: 69% of lupus patients experienced rejection in the first year compared to 58% of controls (P = 0.01). Stratified for age, sex, race and cyclosporine use, this difference remained significant (P = 0.003, relative risk 1.7). Nephrectomy, splenectomy and 3 to 6 months of pretransplant dialysis did not improve graft survival. A dialysis duration of greater than 25 months predicted worse graft survival (P = 0.01). Among lupus patients, PRA did not correlate with graft outcome (P = 0.5), and HLA-identical cadaver grafts had improved outcomes compared to cadaver grafts. We conclude that acute and chronic rejection are the major risk factors for graft loss in lupus patients. The superior outcome of living-related over cadaver grafts in lupus patients suggests an increased role for living-related grafts. Pretransplant dialysis, nephrectomy and splenectomy are not indicated.

Adult↗

Preliminary experience with split liver transplantation.

BACKGROUND: The purpose of split liver transplantation is to alleviate the organ shortage for patients with end-stage liver disease. The procedure, however, has not gained wide acceptance. This is related not only to the complexity of the procedure but also to poorer results and the complications reported to be associated with the technique. STUDY DESIGN: We report 12 split liver transplantation procedures, seven in children and five in adults. Selection criteria were the same as those for whole-size liver transplantation. Patient and graft survival as well as complications were analyzed. Results were analyzed by Wilcoxon life tables. RESULTS: Patient and graft survival rates are 91.6 and 75 percent, respectively. One patient died at 2.5 months after transplantation because of lymphoproliferative disease. Another had acute vanishing bile duct syndrome and required retransplantation at 1.5 months. One patient had retransplantation because of hepatic artery thrombosis. Bile leaks occurred in two patients and hemothorax in one patient. CONCLUSIONS: Our results indicate that split liver transplantation has become a more acceptable method of hepatic transplantation and should be encouraged. Several guidelines can enhance success rates.

Adult↗

Pretransplant status and patient survival following liver transplantation.

The current liver allocation system has been criticized, since available organs go to those who are the most critically ill. These recipients have the poorest overall survival. Identification of pretransplant risk factors for mortality would allow better allocation of donor livers. This study was a retrospective analysis of pretransplant clinical and laboratory parameters and subsequent postoperative liver transplant mortality to identify high-risk subgroups. Of 347 consecutive consecutive primary liver transplant recipients, 59 (17%) met United Network for Organ Sharing (UNOS) criteria for status 4. Pretransplant factors included liver function, coagulation, albumin and ammonia levels, renal function, the presence of ascites, and etiology of liver disease. Overall 1-year patient survival was significantly worse for the status 4 recipients (89.0% vs. 67.7%; P = 0.01). In a univariate analysis of pretransplant risk factors for all recipients, elevated creatinine (P = 0.008) and ammonia (P = 0.009), and UNOS status 4 (P = 0.01) significantly affected postoperative survival. In multivariate analysis of pretransplant risk factors for all recipients, elevated creatinine (P = 0.003) was the only factor to significantly affect postoperative survival. In UNOS status 4 patients, univariate analysis of pretransplant risk factors and their influence on patient survival demonstrated that prolonged coagulation partial thromboplastin time (P = 0.04) and a higher grade of encephalopathy (P = 0.02) significantly affected postoperative survival. Advanced encephalopathy (P = 0.009) and prolonged partial thromboplastin time (P = 0.01) were the only significant risk factors by multivariate analysis in status 4 patients. In status 4 and non-status 4 patients, we identified risk factors that adversely affected patient survival, but their predictive power was insufficient to deny transplantation. Despite the higher mortality in status 4 recipients, their long-term survival is only slightly worse than that of non-status 4 patients. Until better predictors of survival are ascertained, our data do not support limiting the use of donor livers in UNOS status 4 recipients.

Adult↗

Successful extrarenal transplantation from non-heart-beating donors.

The current organ shortage has made utilization of organs from less-than-ideal donors more common. Although several transplant centers use kidneys from non-heart-beating donors (NHBDs), there has been reluctance to extend the use of these donors to extrarenal organs. Of the 130 donors referred to our organ procurement organization between January 1993 and May 1994, 16 (12.3%) were NHBDs. Organ retrieval from 10 of these resulted in extrarenal donation, 5 resulted in renal donation only, and 1 resulted in no retrieval as a result of prolonged warm ischemia (> 2 hr). A total of 39 organs were transplanted from these NHBDs. A rapid en bloc retrieval technique was used for extrarenal NHBDs. The mean warm ischemic time was 15.4 min; preservation times were similar for both NHBDs and heart-beating donors. After liver transplantation (n = 5), one episode of primary nonfunction that was technical in origin required retransplantation. Following simultaneous pancreas-kidney transplantation (n = 6), all patients were insulin independent and free of graft pancreatitis; one patient required hemodialysis (16.7%). After isolated renal transplantation (n = 21), 3 patients (14.3%) required hemodialysis. Three of 4 liver recipients are alive after a mean follow-up period of 12.7 months; all simultaneous pancreas-kidney and renal transplant recipients are alive after a mean follow-up period of 8.4 and 8.3 months, respectively. Three liver allografts, 5 pancreas and kidney allografts, and 19 renal allografts are functioning. The lung allograft was lost to rejection 81 days after transplantation; however, the recipient is alive 3 months after retransplantation. Our results demonstrate that in controlled situations, extrarenal organs can be utilized from NHBDs and can be expected to function similarly to organs retrieved from heart-beating donors. We increased the number of transplanted organs by 8.6% using NHBDs for both renal and extrarenal donation. Continued application of these techniques will likely further increase the number of organs retrieved for transplantation.

Heart↗

FK506 (tacrolimus) compared with cyclosporine for primary immunosuppression after pediatric liver transplantation. Results from the U.S. Multicenter Trial.

We report on the efficacy and safety of FK506 (tacrolimus) compared with a cyclosporine (CsA)-based immunosuppressive regimen after 1 year of treatment in pediatric liver allograft recipients (< 12 years) participating in a multicenter U.S. randomized trial. Patients received either FK506 or CsA as primary immunosuppression following a first ABO-compatible liver transplant. Intravenous FK506 was initiated at 0.1 mg/kg per day, followed by oral FK506 beginning at 0.3 mg/kg per day. The dose was adjusted to maintain plasma trough levels of 0.5-2.0 ng/ml. The CsA group was treated according to each center's usual protocol. Both groups received the same initial doses of corticosteroids. All rejection episodes were biopsy-proven and a standardized algorithm was adopted for the treatment of rejection. Thirty patients were randomized to the FK506 group and 20 to the CsA group. After twelve months of follow-up 20 patients remained in the FK506 group and 13 in the CsA group. Patient survivals were 80% and graft survival 70% in the FK506 group compared with 81% and 71% respectively, in the CsA group. 48% of the FK506 group remained rejection-free compared with 21% of the CsA group, and 79% of FK506-treated patients did not require OKT3 compared with 68% of CsA treated patients. The cumulative corticosteroid dose was less at each time point throughout the first year in the FK506 group. The incidence of serious and minor infections was similar in both groups. Nephrotoxicity, neurotoxicity, and gastrointestinal disturbances were the major toxicities reported. Differences did not reach statistical significance between the two groups although major neurologic events, diarrhea and dyspepsia were more often reported in the FK506 group. There was no difference in mean serum creatinine at 12 months between the two groups. There was a tendency toward lower mean serum cholesterol in the FK506 group. There was no hirsuitism in the FK506 group compared with a 30% incidence in the CsA group. In conclusion, compared with CsA, there is a trend toward less rejection in FK506-treated pediatric allograft recipients, while both drugs have a similar spectrum of side effects.

Adrenal Cortex Hormones↗

Relationships between sclerosing cholangitis, inflammatory bowel disease, and cancer in patients undergoing liver transplantation.

BACKGROUND: Liver transplantation has emerged as the definitive treatment for primary sclerosing cholangitis (PSC). Its relationships to inflammatory bowel disease and cholangiocarcinoma were evaluated in this series. METHODS: Fifty-three liver transplantations were performed in 41 patients with PSC at the University of Wisconsin from 1986 through 1994. Fourteen of the patients underwent colectomies for inflammatory bowel disease, eight before transplantation and six after transplantation. Five patients had cholangiocarcinoma on the hepatectomy specimen, and another two had been diagnosed before transplantation. RESULTS: Patient survival for PSC without cholangiocarcinoma was 85% and 62% at 2 and 9 years, respectively. No patient with PSC and cholangiocarcinoma has survived 2 years, although two patients were free of disease 11 and 20 months after transplantation. Despite maintenance immunosuppression seven patients with liver transplants had reactivation of inflammatory bowel disease and colon carcinoma developed in three after liver transplantation. CONCLUSIONS: Liver transplantation should be performed early in the course of PSC to avoid the lethal complications of cholangiocarcinoma. Careful colonoscopic follow-up is necessary in patients undergoing transplantation for PSC because immunosuppressive therapy does not necessarily cause inflammatory bowel disease to be quiescent, nor does it reduce the risk of colon carcinoma developing.

Adenocarcinoma↗

Living related and unrelated donors for kidney transplantation. A 28-year experience.

OBJECTIVE: The objective of this study was to analyze a single center's 28-year experience with 1000 living donor transplants. SUMMARY BACKGROUND DATA: The number of potential renal transplant recipients far exceeds the number of cadaveric donors. For this reason, living related donors (LRDs) and, more recently, living unrelated donors (LURDs) have been used to decrease the cadaveric donor shortage. METHODS: From November 15, 1966, until August 5, 1994, 1000 living donor transplants were performed; 906 were living related and 94 were living unrelated transplants. Results were divided into precyclosporine (1966-1986, era I) and cyclosporine (1986-1994, era II) eras. Patient and graft survivals were compared between diabetic and nondiabetic recipients, between LRDs and LURDs, and according to human leukocyte antigen (HLA) matching. Donor mortality, morbidity, and postoperative renal function were also analyzed. RESULTS: The 5-, 10-, and 20-year graft survivals were 78.8%, 64.8%, and 43.4%, respectively. Patient and graft survival improved in era II (patient = 87.0% vs. 81.7%, p = 0.03; graft = 72.9% vs. 67.7%, p = 0.04). Nondiabetic patient and graft survivals were better than diabetic patient survivals in both eras. However, diabetic patient survival improved in era II (78.0% vs. 66.9%, p = 0.04). In era II, HLA-identical recipients had better graft survival than haploidentical or mismatched recipients (91.7% vs. 67.3% and 66.1%, p = 0.01). No difference between haploidentical LRDs and LURDs was seen. One donor death occurred in 1970, and 17% of donors developed postoperative complications. CONCLUSION: Living related and unrelated renal donation continues to be an important source of kidneys for patients with end-stage renal disease.

Adult↗

100 consecutive liver transplants in infants and children: an 8-year experience.

Orthotopic liver transplantation has become the treatment of choice for most children and infants with end-stage liver disease. The purpose of this retrospective study was to examine the results of 100 consecutive liver transplants performed in infants and children at a single institution. During an 8-year study period (July 1984 to December 1992), 100 pediatric liver transplants were performed in 76 patients. Thirty-four patients (44.7%) were infants (mean age, 7.0 months; mean weight, 6.1 kg), and 42 (55.3%) were children (mean age, 8.2 years; mean weight, 30.6 kg). There were 36 reduced-size liver transplants (RLT) and 64 whole-size transplants (WLT). Eight infants (23.5%) and 10 children (20.7%) required retransplantation. After transplantation, 71% of the patients had one or more rejection episodes, 66% had one or more infections, 17.1% had biliary complications, and 39.4% required one or more reoperations. There were 17 deaths. The actuarial 8-year survival rate for the patients with biliary atresia was 82.3%; for all infants in this series, it was 77.6%. No difference in patient survival was noted when RLT was compared with WLT. The overall 8-year actuarial patient survival rate for infants and children was 77.3%.

Adolescent↗

Living-unrelated renal donor transplantation: the UNOS experience, 1987-1991. United Network for Organ Sharing.

1. LURD transplants were associated with excellent one-year graft survival of 92%. This survival was superior to that for cadaver transplants performed during the same period. 2. High-risk groups for LURDs are children (age < 18 years) and repeat transplant recipients. Both groups were associated with significantly decreased graft survival. 3. The effects of HLA matching and donor-specific transfusions are not significant. 4. Because of the critical shortage of donor organs and the increasing waiting time for renal transplantation, the use of LURDs can be recommended as a means to expand the number of available organs.

Adolescent↗

Portal hypertension: surgical management in the 1990s.

BACKGROUND: Although liver transplantation offers definitive treatment for portal hypertension with end-stage liver failure, surgical portosystemic shunts avoid the risks of transplantation and immunosuppressive therapy, and transjugular intrahepatic portosystemic shunt (TIPS) creates a portosystemic shunt with minimal operative risk. The appropriate applications of these modalities are discussed. METHODS: All adults undergoing primary liver transplantation alone (PLT, n = 265), PLT after TIPS (n = 34), PLT after surgical shunts (n = 12), surgical shunt alone (n = 13), TIPS alone (n = 35), or surgical shunt after PLT (n = 5) served as the basis of this study. RESULTS: In contrast to surgical shunts before PLT, TIPS before PLT increased the 1-year graft survival. Surgical shunts alone were done in 18 patients with normal or near normal liver function with 100% survival. TIPS alone offered effective symptomatic relief to most patients, all of whom were judged not to be surgical candidates. CONCLUSIONS: TIPS, surgical shunts, and liver transplantation each have a logical role in management of portal hypertension. Surgical candidates with Child's B or C liver failure should be treated with liver transplantation, and TIPS offers effective treatment for nonsurgical candidates. Surgical shunts can be performed with excellent results in patients with Child's A liver disease. Portal vein occlusion with normal liver function can be successfully treated with surgical shunts.

Adolescent↗

A controlled, double-blind, randomized trial of verapamil and cyclosporine in cadaver renal transplant patients.

Calcium channel blockers have immunomodulating effects in vitro and may be effective in preventing cyclosporine nephrotoxicity. We studied the effect of verapamil following renal transplantation on the incidence of rejection and cyclosporine nephrotoxicity in a double-blind, placebo-controlled trial. Patients were randomly assigned to placebo (n = 28) or verapamil (n = 32) at doses of 80 mg twice a day. There was no difference in the incidence of rejection or cyclosporine toxicity in the two study arms. Recipients randomized to verapamil had lower mean cyclosporine doses at all intervals during a 1-year follow-up. Although cyclosporine doses were lower in the placebo group, the mean cyclosporine levels were equivalent in the two groups. Recipients in the verapamil-treated group had a higher mean serum creatinine at the end of the study--1.7 mg/dL versus 1.4 mg/dL in the placebo group. Actual 1-year graft survival was 89% for the placebo recipients versus 91% in the verapamil-treatment group. When compared with placebo, the concomitant use of low-dose verapamil results in lower cyclosporine doses but equivalent cyclosporine blood levels. Reduction in the incidence of rejection or cyclosporine nephrotoxicity were not observed.

Adult↗

Urological complications in 210 consecutive simultaneous pancreas-kidney transplants with bladder drainage.

OBJECTIVE: The urological complications of 210 patients who underwent simultaneous pancreas-kidney (SPK) transplantation over a 7-year period were reviewed. SUMMARY BACKGROUND DATA: Worldwide, bladder drainage has become the accepted method of exocrine drainage after pancreas transplantation. With the increasing use of bladder drainage, the surgical post-transplant complications have shifted from intra-abdominal complications to urological complications. METHODS: Two hundred ten diabetic patients received SPK transplants with bladder drainage. A retrospective review was conducted to analyze the incidence, type, and management of urological complications. RESULTS: The most frequent urological complications were hematuria, leak from the duodenal segment, recurrent urinary tract infections, urethritis, and ureteral stricture and disruption. Complications related to the renal transplant included ureteral stricture and leaks, as well as lymphoceles. CONCLUSIONS: Despite the high incidence of urological complications, 5-year actuarial patient and graft survival are excellent. Only one graft and one patient were lost secondary to urological complications.

Adult↗