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R Pollak

Publications and source records attributed to R Pollak.

At least 19 recordsLinked to original sources
PubMed1999

A prospective randomized trial comparing the efficacy of tacrolimus versus cyclosporine in black recipients of primary cadaveric renal transplants.

BACKGROUND: We performed a prospective randomized trial to compare the efficacy and safety of tacrolimus (FK506) versus cyclosporine (CSA) in black primary cadaveric renal transplant (CRT) recipients. METHODS: Between December 1994 and February 1997, 35 black primary CRT recipients were enrolled in this trial. All patients received 7 days of induction therapy with OKT3. Fourteen patients received FK506 and prednisone only. Twenty-one patients received CSA, azathioprine, and prednisone. The two groups were comparable in terms of age, gender, plasma renin activity, human leukocyte antigen mismatches, and cause of renal failure. RESULTS: Patient and graft survival were 12 of 14 (86%) for the FK506 group and 20 of 21 (95%) for the CSA group (P = 0.71). Three patients died owing to cardiac events with functioning grafts. Acute rejection was 2 of 14 (14%) for the FK506 and 8 of 21 (38%) for the CSA group (P = 0.25). Two other patients on CSA were converted to FK506 as rescue for OKT3-resistant rejection. Mean serum cholesterol at 1 year was 198 +/- 45 mg/dL for the FK506 group and 244 +/- 49 mg/dL for the CSA group (P = 0.03). Mean serum creatinine at 1 year was 1.39 +/- 0.38 mg/dL for the FK506 group and 1.94 +/- 0.64 mg/dL for the CSA group (P = 0.02). CONCLUSION: Patient and graft survival were similar in both groups at 1 year posttransplant. Although statistically not significant, the incidence of acute rejection was lower in the FK506 group. Furthermore, FK506-treated patients had significantly lower serum creatinine and cholesterol levels at 1 year posttransplant.

Adult↗
PubMed1999

Cyclosporine bioavailability of Neoral and Sandimmune in white and black de novo renal transplant recipients. Neoral Study Group.

Black renal transplant recipients have inferior graft outcomes when compared to whites. The relative bioavailability of cyclosporine (CsA) with the Sandimmune (SIM) formulation is lower in black recipients when compared to whites. To study relative CsA bioavailability in the Neoral formulation, 18 black and 78 white de novo renal transplant recipients were randomized in a multicenter, double-blind, parallel group study to receive either SIM or Neoral capsules twice a day for 12 weeks. After an overnight fast, CsA whole blood levels (TDx) were collected during 12 hours after the morning dose and 12 hours after the evening dose with a standardized meal. Pharmacokinetic profiles were obtained at the end of weeks 1, 4, 8, and 12. Initial CsA dose was 5 mg/kg twice a day; subsequent doses were titrated to target trough CsA levels. Area under the blood concentration vs. time curve (AUC), peak blood concentration (Cmax) and time to Cmax(Tmax) were obtained from 16 black and 73 white patients. Food conditions (fed and fasting) were averaged, and data was dose-normalized. For black recipients, Neoral was significantly more bioavailable than SIM only during week 1; there was also a consistent trend to higher cyclosporine bioavailability at weeks 4, 8, and 12. For whites, there were significant differences in favor of Neoral at all time periods. No significant differences in relative bioavailability were noted between races for either SIM or Neoral except for a higher Cmax in white patients given Neoral. Neoral is better absorbed than SIM in both blacks and whites. These data suggest that Neoral is the superior CsA preparation for all racial groups.

Adult↗
PubMed1999

Long-term outcome of a prospective trial of steroid withdrawal after kidney transplantation.

BACKGROUND: Steroid withdrawal (SW) after kidney transplantation is desirable to avoid associated serious side effects. We studied the long-term outcome of a group of kidney transplant recipients who underwent SW. METHODS: Between 1991 and 1993, kidney transplant recipients (N = 12) who had posttransplantation diabetes were entered in a prospective trial of SW. These patients were compared with a demographically similar comparison cohort (N = 66). End points of the study were patient and graft survival, incidence of late acute and chronic rejection, and changes in diabetes management. RESULTS: Previously published data from the SW group at 15 months of follow-up indicated improvement in diabetes control without any adverse effect on patient or graft actuarial survival. At long-term follow-up (mean, 56 months) the improvement in diabetes management was not detectable. The incidence of late acute rejection in SW and cohort groups was 42% and 8%, respectively (P = .006). Likewise, the incidence of chronic rejection in the SW versus cohort group was 42% and 12%, respectively (P = .014). CONCLUSIONS: Although SW appeared to be successful initially, our long-term data indicate that SW significantly increases the risk of late acute rejection and chronic rejection episodes without benefits in posttransplantation diabetes management. Steroid withdrawal in patients with posttransplantation diabetes should be approached with caution.

Acute Disease↗
PubMed1998

A prospective randomized clinical trial of perioperative treatment with octreotide in pancreas transplantation.

BACKGROUND: Technical failures continue to plague clinical pancreas transplantation. The somastatin analogue octreotide has been shown able to decrease morbidity after pancreatic resection. We studied the effect of perioperative treatment with octreotide on technical complications after pancreas transplant. PATIENTS AND METHODS: Seventeen recipients of bladder-drained transplant were randomized to receive either octreotide, 100 microg TID SQ for 5 days after transplant (n = 10) or no additional treatment (n = 7). We compared the two groups in terms of patient and graft survival and incidence of graft pancreatitis, intra-abdominal infections, and anastomotic leaks. RESULTS: In the untreated group, 1 patient developed a bladder leak and 2 had intra-abdominal infections, while no complications occurred in the octreotide-treated patients (P = 0.05). Six-month patient and pancreas survival was 100% and 90%, respectively, in octreotide-treated patients versus 86% and 86% in the control group (P = NS). CONCLUSION: Perioperative treatment with octreotide seems able to reduce the incidence of technical complications after pancreas transplantation.

Adult↗
PubMed1998

Combined coronary bypass and liver transplantation: technical considerations.

Combined coronary artery bypass grafting and orthotopic liver transplantation was carried out successfully in a 58-year-old man with angina pectoris and end-stage liver disease. To date, only 2 similar cases have been documented worldwide whereby the transplantation was performed either during cardiopulmonary bypass or with femoral-to-axillary venovenous bypass initiated at the termination of cardiopulmonary bypass. In this report we describe our experience with a simplified one-exposure approach for the combined operation using cardiopulmonary bypass in tandem with percutaneous femoral-to-right atrial venovenous bypass.

Angina Pectoris↗
PubMed1998

Kidney transplantation in recipients with mental retardation: clinical results in a single-center experience.

Mental retardation has been a controversial relative contraindication to organ transplantation. Currently, there are few data available in the literature that describe the outcome of kidney transplantation in mentally retarded patients. In a series of 1,271 kidney transplantations performed between January 1968 and March 1996, we identified eight patients (0.6%) with significant mental retardation (IQ < 70). Only cooperative patients supervised by a reliable long-term caregiver, with long life expectancy, and able to take medication under supervision, were accepted as candidates, independent of the IQ level. At a mean follow-up of 7.3 years, seven patients are alive with functioning grafts, and one lost the kidney to chronic rejection 10 years after transplantation and died of sepsis after resuming dialysis. The 1- and 5-year patient and graft survival are thus 100%. Compliance with immunosuppressive treatment and clinical follow-up was excellent in all of the recipients. The patient quality of life and health were judged by the support persons as highly improved after transplantation in comparison to dialysis. We conclude that kidney transplantation in properly selected patients with mental retardation provides excellent patient and graft survival rates and improves quality of life. In such patients, the presence of mental retardation should not be considered a contraindication to kidney transplantation.

Adolescent↗
PubMed1998

A prospective study of the predictive value of polymerase chain reaction assay for cytomegalovirus in asymptomatic kidney transplant recipients.

Cytomegalovirus (CMV) infection carries the potential for high morbidity in transplant recipients. The institution of pre-emptive therapy prior to the onset of clinical disease on the basis of CMV-polymerase chain reaction (PCR) is very attractive. We prospectively studied 52 asymptomatic kidney transplant recipients to test the hypothesis that serial CMV-PCR assays during the first 3 months post-transplant would identify patients at risk for CMV disease. Twenty-three patients (44.2%) had positive CMV-PCR tests at least once; 2 (8.6%) developed CMV. None of the 29 patients continuously negative for CMV-PCR developed CMV disease. CMV-PCR status did not influence patient and graft survival or the incidence of acute rejection. We conclude that while a substantial number of kidney transplant recipients become positive for CMV-PCR in the early post-transplant period, only a minority will develop CMV disease. Negative CMV-PCR assay is an accurate negative predictor for CMV disease but the value of CMV-PCR as a guide for pre-emptive anti-CMV therapy in kidney transplant recipients appears limited.

Adult↗
PubMed1997

Intrasplenic hepatocyte allotransplantation in dalmation dogs with and without cyclosporine immunosuppression.

Hepatocyte allotransplantation has been performed successfully in several small animal models for the amelioration of inborn metabolic errors. Before a human clinical trial of hepatocyte allotransplantation can be attempted, preliminary experience in a large animal model is needed. We transplanted isolated mongrel hepatocytes into the spleen of dalmatians in the attempt to cure their inborn error of uric acid metabolism. Of 10 dalmatian recipients, two that received 9-10 x 10(9) mongrel hepatocytes died early after surgery of acute portal hypertension and hemorrhage. The eight long-term survivors received 5-6 x 10(9) hepatocytes and were randomized either to no treatment or to oral cyclosporine (CsA). Levels of CsA were adjusted to maintain trough levels between 400 and 800 ng/ml. In the four nonimmunosuppressed dalmatians, a reproducible average reduction in urinary uric acid excretion (UUAEx) of 23.7% was achieved; values returned to baseline within 14 days. In the CsA-immunosuppressed dalmatians, the average decline in UUAEx was 30%. The partial correction of the metabolic defect persisted for an average of 25 days in three immunosuppressed dogs, whereas in one dog, the partial correction lasted for over 90 days. No change in UUAEx was observed in two dalmatians that underwent sham laparotomy and intrasplenic injection of saline solution; CsA given alone to dalmatians did not modify UUAEx. We conclude that the dalmatian dog is a valuable large animal model for studies of the role of hepatocyte transplantation in the cure of inborn hepatic metabolic errors.

Animals↗
PubMed1997

Safety and tolerability of cyclosporine microemulsion versus cyclosporine: two-year data in primary renal allograft recipients: a report of the Neoral Study Group.

BACKGROUND: The new microemulsion formulation of cyclosporine (CsA-ME) is more bioavailable than cyclosporine (CsA) in de novo renal transplant patients. Therefore, it was of interest to compare the safety profile of each formulation in such patients. METHODS: In a multicenter, double-blind, parallel-group study, 101 renal transplant recipients were randomized after transplantation to receive either CsA (n=50) or CsA-ME (n=51) capsules twice daily for 2 years. Of these patients, 54 (CsA, n=26; CsA-ME, n=28) completed 1 year of the study and entered the second-year, double-blind extension. Initial dose at the time of transplantation was 5 mg/kg b.i.d.; doses were titrated to target trough levels. METHODS: The mean (+/- SD) doses at the end of 2 years were 4.6 +/- 1.8 and 3.8 +/- 1.1 mg/kg per day for CsA- and CsA-ME-treated patients, respectively. The mean (+/- SD) CsA trough levels at end point were 187 +/- 63 and 210 +/- 95 ng/ml for CsA- and CsA-ME-treated patients, respectively. At least one adverse event was reported by 25/26 (96%) of CsA- and 27/28 (96%) of CsA-ME-treated patients. No patient discontinued the study because of adverse events. No deaths occurred during the study. Renal function, as measured by serum creatinine levels, and blood pressure were comparable over time in both treatment groups. CONCLUSIONS: There was no significant difference in safety and tolerability between CsA- and CsA-ME-treated kidney recipients for 2 years after transplantation.

Adolescent↗
PubMed1997

Safety of oral terbinafine for toenail onychomycosis.

This open-label multicenter study evaluated the safety and efficacy of 12, 18, and 24 weeks of daily treatment with a 250-mg tablet of terbinafine for onychomycosis of the toenails. The safety data for 1,508 patients with a mean age of 50 years are reported here. Percentages below are based on this denominator. All patients received at least 12 weeks of therapy, with a possible addition of 6 or 12 weeks depending on disease extent. Patients were evaluated at baseline and at weeks 6, 12, 24, 30, 36, 48, and 72. Adverse events were reported in 674 (44.7%) patients; the events were considered unrelated to terbinafine in 557 (36.9%) patients and causally related or of uncertain relationship to terbinafine in 117 (7.8%) patients. Most events involved the skin, the gastrointestinal system, or the respiratory system. Statistically similar results were found for the elderly (over 60 years) and diabetic subpopulations. The study results confirm the safety of terbinafine in the population at large and show no differences for either the elderly or diabetic patients, who are at increased risk for onychomycosis and who frequently take concomitant medications with potential for drug interactions.

Antifungal Agents↗
PubMed1997

OKT3 therapy increases cyclosporine blood levels.

Numerous drugs have been reported to alter cyclosporine (CSA) blood levels, most notably, those drugs that interfere with cytochrome P450 metabolism. Our clinical experience suggested that OKT3 therapy may alter CSA blood levels as well. The purpose of this study was to assess the effect of OKT3 therapy on CSA trough blood levels. We reviewed medical records of all CSA-treated renal transplant recipients during a 3-yr period to identify patients who received antilymphocyte induction therapy. Patients receiving drugs known to interact with CSA were excluded from analysis. The study population (n = 33) was divided into two groups: the OKT3 group consisting of 17 patients who received OKT3 therapy for 7 d post-transplant (OKT3 group) and the control consisting of 16 patients who received ALG induction therapy for 7 d post-transplant (ALG group). Oral CSA (14 mg/kg) was administered preoperatively. Postoperatively, oral CSA (4 mg/kg) was administered twice daily, in addition to corticosteroids and azathioprine. We evaluated CSA through levels on days 1, 3, 5, and 7 of antilymphocyte therapy and 3 d following completion of antilymphocyte therapy. On days 1 and 3, CSA trough levels did not differ between the two groups. However, median CSA trough levels (HPLC) were significantly higher among OKT3-treated patients on day 5 of therapy (265 ng/ml), as compared to ALG-treated patients (136 ng/ml; p < 0.0001; Mann-Whitney U-test). On days 7 and 10, CSA trough levels did not differ between the two groups. CSA does, however, had been adjusted based on levels obtained on day 5. We conclude that OKT3 therapy causes a significant rise in CSA trough levels. Recognition of this potential drug interaction is essential in titrating CSA doses in the early post-transplant period to minimize risks of CSA toxicity or early rejection following induction therapy.

Adult↗
PubMed1997

Thrombocytopenia in an established solitary pancreas graft recipient.

Isolated, life-threatening thrombocytopenia from a previously well tolerated pancreas allograft has not been reported in the literature. Herein we report such a case where a 31-year-old, Caucasian, Type I diabetic male developed severe thrombocytopenia 6 months following isolated pancreas transplantation and 2 wk after enteric conversion of the graft. Despite extensive diagnostic work-up, the cause remained unclear and his thrombocytopenia did not remit with standard treatment, but did resolve upon explantation. Pathologic examination of the pancreatic graft showed evidence of chronic rejection along with CMV pancreatitis. We conclude that unremitting isolated thrombocytopenia in solitary pancreas grafts may reflect a localized DIC phenomenon that requires graft explantation.

Adult↗
PubMed1997

Iliac reconstruction with arterial allograft during pancreas-kidney transplantation.

An intraoperative dissection of the external iliac artery during pancreas transplantation was successfully repaired using the donor iliac artery allograft as a conduit between the internal iliac and distal external iliac artery. An angiogram performed 6 months after surgery showed a patent bypass without stricture or pseudoaneurysm. At 1 yr follow-up after transplant the grafts are functioning well, and the affected extremity is normal. In immunosuppressed recipients of solid organ transplants, fresh arterial allografts may be successfully used for iliac artery reconstruction. Further study will be needed to determine the role of arterial allografts for lower extremity bypass surgery in immunosuppressed patients.

Adult↗