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C A Vivas

Publications and source records attributed to C A Vivas.

At least 19 recordsLinked to original sources
PubMed2005

The cost of steroid-free protocols in primary cadaver kidney transplantation.

Steroid-free immunosuppression regimens have been enjoying recent success in clinical transplantation. The use of antibodies required for such protocols can be an economic burden. We proposed to study their cost in our center. This retrospective study involved 147 consecutive patients subjected to 4 protocols of immunosuppression. The first received triple therapy. The second group received induction with basiliximab, whereas the third received Basiliximab plus cyclosporine (CSA) plus mycophenolate mofetil (MMF), and the fourth received Thymoglobulin plus CSA plus MMF in conjuction with only 4 days of steroid. Rejection episodes were treated with Solumedrol. Six-month charges were obtained from computerized records of the finance department, the in-house laboratories, and the transplantation service registry. All charges were expressed in 2004 dollars. Statistical analyses were obtained using chi-square, analysis of variance (ANOVA) and Kaplan-Meier tests. The 4 groups were similar with regard to donor and/or recipient gender, race, panel reactive antibodies, cold ischemia, dialysis requirements length of stay and readmission, graft survival, and function. Charges were significantly higher in the last 2 groups as compared with triple therapy.

Adult↗
PubMed2001

Reversal of steroid- and anti-lymphocyte antibody-resistant rejection using intravenous immunoglobulin (IVIG) in renal transplant recipients.

BACKGROUND: Despite the recent advances in immunosuppression, steroid-resistant rejection remains a difficult problem in renal transplant recipients. METHODS: We reviewed our experience with i.v. immunoglobulin (IVIG) in the treatment of steroid- and antilymphocyte antibody-resistant rejection in renal transplant patients. Between September 1996 and March 1999, 17 patients were treated with IVIG to reverse steroid- or antilymphocyte antibody-resistant rejection. A total of 2 g/kg of IVIG was administered to patients during each treatment course. RESULTS: With a mean follow-up of 21.5+/-9.5 months from the time of IVIG administration, patient and graft survival rates were 94% (16/17) and 71% (12/17), respectively. The baseline mean serum creatinine level prior to rejection was 2.2+/-0.7 mg/dl and peaked at 3.3+/-1.1 mg/dl at the time of the diagnosis of refractory rejection. IVIG therapy was associated with a fall in the mean creatinine to 2.8+/-1.1 mg/dl. The most recent serum creatinine in patients with functioning grafts was 2.8+/-1.6 mg/dl. In 82% of allograft biopsies after IVIG, reversal or reduction in the severity of rejection was demonstrated. In addition, IVIG therapy rescued three of four patients with antilymphocyte antibody-resistant rejection. CONCLUSIONS: IVIG rescue therapy for steroid- or antilymphocyte antibody-resistant rejection is associated with resolution or improvement of rejection severity, stable renal function, and reasonable graft survival.

Adult↗
PubMed2000

Renal allograft rejection with normal renal function in simultaneous kidney/pancreas recipients: does dissynchronous rejection really exist?

BACKGROUND: Between July 1, 1994 and December 1, 1998, 147 simultaneous kidney/pancreas transplantations were performed at our center. Of 95 patients who experienced at least one acute renal allograft rejection episode after transplantation, 7 (7.4%) developed rejection in the presence of stable and normal or near-normal renal function. METHODS: The indication for renal allograft biopsy was a rising serum lipase, i.e., suspected pancreatic rejection. All seven patients were treated with steroids and augmentation of the tacrolimus dose, with a fall in the serum lipase and no change in the serum creatinine. RESULTS: The serum creatinine levels just before, at the time of, 1 week after the biopsy, and at most recent follow-up were 1.4+/-0.4, 1.3+/-0.3, 1.2+/-0.2, and 1.2+/-0.2 mg/dl. The serum lipase levels just before, at the time of, 1 week after the biopsy, and at most recent follow-up were 1022+/-1157 mg/dl, 874+/-996 mg/dl, 243+/-260 mg/dl, and 94+/-75 mg/dl. The tacrolimus dosages and levels at the time of the biopsy and 1 week later were 14.9+/-5.0 mg/day and 15.0+/-4.0 ng/ml, and 16.4+/-6.3 mg/day and 15.1+/-6.8 ng/ml. CONCLUSIONS: These findings suggest that, in patients undergoing simultaneous kidney/pancreas transplantation, the entity of dissynchronous pancreatic allograft rejection without renal allograft rejection may not really exist. These data also make an additional fundamental point that acute rejection may occur in patients with normal and stable renal function.

Graft Rejection↗
PubMed2000

Results of pancreas transplantation after steroid withdrawal under tacrolimus immunosuppression.

PURPOSE: The results of steroid withdrawal in pancreas transplant recipients under tacrolimus immunosuppression were analyzed. METHODS: From July 4, 1994 until April 30, 1998, 147 pancreas transplantations were performed in 141 patients, including 126 simultaneous pancreas-kidney transplantations, 13 pancreas after kidney transplantation, and 8 pancreas transplantations alone. Baseline immunosuppression consisted of tacrolimus and steroids without antilymphocyte induction. Twenty-three patients were excluded from analysis because of early graft loss in 17 cases, retransplantation in 5 cases, and simultaneous pancreas-kidney transplantation after heart transplantation in 1 patient. RESULTS: With a mean follow-up of 2.8+/-1.1 years (range 1.0 to 4.8 years), complete steroid withdrawal was achieved in 58 (47%) patients with a mean time to steroid withdrawal of 15.2+/-8 months (range 4 to 40 months after transplantation). Of the entire cohort of 141 patients, overall 1-, 2-, and 4-year patient survival rates were 98%, 95.5%, and 86%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 83%, 80%, and 71% (pancreas) and 95%, 91%, and 84% (kidney), respectively. Of the 124 patients analyzed for steroid withdrawal, 1-, 2-, and 4-year patient survival rates were 98%, 97%, and 92%, respectively. Overall 1-, 2-, and 4-year graft survival rates were 98%, 91.5%, 83% (pancreas) and 97%, 95%, and 91% (kidney). Patient, pancreas, and kidney survival rates at 1 year were 100%, 100%, and 98% (off steroids) versus 97%, 91%, and 96% (on steroids, all NS) and at 4 years were 100%, 94%, and 95% (off steroids) versus 78%, 68%, and 85% (on steroids, P = 0.01, 0.002, and NS, respectively). The cumulative risk of rejection at the time of follow-up was 76% for patients on steroids versus 74% for patients off steroids (P = NS). Seven patients originally tapered off steroids were treated for subsequent rejection episodes, which were all steroid sensitive, and two of these seven patients are currently off steroids. Thirteen patients received antilymphocyte therapy for steroid-resistant rejection, five of whom are now off steroids. Tacrolimus trough levels were 9.3+/-2.4 ng/ml (off steroids) and 9.7+/-4.3 (on steroids, P = NS). Mean fasting glucose levels were 98+/-34 mg/dl (off steroids) and 110+/-41 mg/dl (on steroids, P = NS). Mean glycosylated hemoglobin levels were 5.2+/-0.9% (off steroids) and 6.2+/-2.1% (on steroids, P = 0.02), and mean serum creatinine levels were 1.4+/-0.8 mg/dl (off steroids) and 1.7+/-1.0 mg/dl (on steroids, P = 0.02). CONCLUSION: These data show for the first time that steroid withdrawal can be safely accomplished in pancreas transplant recipients maintained on tacrolimus-based immunosuppression. Steroid withdrawal is associated with excellent patient and graft survival with no increase in the cumulative risk of rejection.

Graft Rejection↗
PubMed1999

Long-term results of pancreas transplantation under tacrolius immunosuppression.

BACKGROUND: The long-term safety and efficacy of tacrolimus in pancreas transplantation has not yet been demonstrated. The observation of prolonged pancreatic graft function under tacrolimus would indicate that any potential islet toxicity is short-lived and clinically insignificant. We report herein the results of pancreas transplantation in patients receiving primary tacrolimus immunosuppression for a minimum of 2 years. METHODS: From July 4, 1994 until April 18, 1996, 60 patients received either simultaneous pancreas-kidney transplant (n=55), pancreas transplant only (n=4), or pancreas after kidney transplantation (n=1). Baseline immunosuppression consisted of tacrolimus and steroids without antilymphocyte induction. Azathioprine was used as a third agent in 51 patients and mycophenolate mofetil in 9. Rejection episodes within the first 6 months occurred in 48 (80%) patients and were treated with high-dose corticosteroids. Antilymphocyte antibody was required in eight (13%) patients with steroid-resistant rejection. RESULTS: With a mean follow-up of 35.1+/-5.9 months (range: 24.3-45.7 months), 6-month and 1-, 2-, and 33-year graft survival is 88%, 82%, 80%, and 80% (pancreas) and 98%, 96%, 93%, and 91% (kidney), respectively. Six-month and 1-, 2-, and 3-year patient survival is 100%, 98%, 98%, and 96.5%. Mean fasting glucose is 91.6+/-13.8 mg/dl, and mean glycosylated hemoglobin is 5.1+/-0.7% (normal range: 4.3-6.1%). Mean tacrolimus dose is 6.5+/-2.6 mg/day and mean prednisone dose 2.0+/-2.9 mg/day at follow-up. Complete steroid withdrawal was possible in 31 (65%) of the 48 patients with functioning pancreases. CONCLUSIONS: These data show for the first time that tacrolimus is a safe and effective long-term primary agent in pancreas transplantation and provides excellent long-term islet function without evidence of toxicity while permitting steroid withdrawal in the majority of patients.

Actuarial Analysis↗
PubMed1999

Simultaneous administration of adjuvant donor bone marrow in pancreas transplant recipients.

OBJECTIVE: The effect of donor bone marrow was evaluated for its potentially favorable effect in the authors' simultaneous pancreas/kidney transplant program. METHODS: From July 1994 to January 1999, 177 pancreas transplants were performed, 151 of which were simultaneous pancreas/kidney transplants. All patients received tacrolimus, mycophenolate mofetil, and steroids for immunosuppression (azathioprine was used in the first year of the program). Fifty-three simultaneous pancreas/kidney transplant recipients received perioperative unmodified donor bone marrow, 3 to 6 x 10(8) cells/kg. RESULTS: Overall actuarial survival rates at 1 and 3 years were 98% and 95% (patient), 95% and 87% (kidney), and 86% and 80% (pancreas), respectively. In the adjuvant bone marrow group, 1- and 3-year survival rates were 96% and 91 % (patient), 95% and 87% (kidney), and 83% and 83% (pancreas), respectively. For 98 recipients who did not receive bone marrow, survival rates at 1 and 3 years were 100% and 98% (patient), 96% and 86% (kidney), and 87% and 79% (pancreas), respectively. No pancreas allografts were lost after 3 months in bone marrow recipients, and seven in the non-bone marrow recipients were lost to rejection at 0.7, 6.7, 8.8, 14.6, 24.1, 24.3, and 25.5 months. Twenty-two percent of bone marrow patients were steroid-free at 1 year, 45% at 2 years, and 67% at 3 years. Nineteen percent of the non-bone marrow recipients were steroid-free at 1 year, 38% at 2 years, and 45% (p = 0.02) at 3 years. The mean acute cellular rejection rate was 0.94+/-1.1 in the bone marrow group and 1.57+/-1.3 (p = 0.003) in the non-bone marrow group (includes borderline rejection and multiple rejections). The level of donor cell chimerism in the peripheral blood of bone marrow patients was at least two logs higher than in controls. CONCLUSION: In this series, which represents the largest experience with adjuvant bone marrow infusion in pancreas recipients, there was a higher steroid withdrawal rate (p = 0.02), fewer rejection episodes, and no pancreas graft loss after 3 months in bone marrow recipients compared with contemporaneous controls. All pancreas allografts lost to chronic rejection (n = 6) were in the non-bone marrow group. Donor bone marrow administered around the time of surgery may have a protective effect in pancreas transplantation.

Actuarial Analysis↗
PubMed1999

Simultaneous pancreas-kidney transplantation at the University of Pittsburgh.

Analysis of the SPK program at the University of Pittsburgh has led to a number of observations: 1. Under tacrolimus-based immunosuppression, without antibody induction, it has been possible to achieve (a) One- and 3-year actuarial patient survival rates of 98% and 95% (b) One- and 3-year actuarial kidney survival rates of 95% and 87% (c) One- and 3-year actuarial pancreas survival rates of 86% and 80% 2. Steroid withdrawal has been achieved in over half of the successfully transplanted recipients, with excellent outcomes and a low rate (4.7%) of subsequent rejection. 3. Bone marrow augmentation has been associated with (a) less rejection (b) less pancreatic graft loss to rejection (c) an increased ability to withdraw steroids 4. Rejection has been associated with a rising serum lipase. 5. Renal allograft rejection in SPK patients with elevated serum lipase levels has been seen in the setting of normal renal function. 6. Enteric drainage has been associated with a reasonably low complication rate. 7. SPK transplantation is a successful therapeutic option in selected type I diabetics with end-stage renal disease.

Adult↗
PubMed1998

Tacrolimus without antilymphocyte induction therapy prevents pancreas loss from rejection in 123 consecutive patients.

In this series, antilymphoid induction therapy did not appear to be necessary to prevent early graft loss from rejection. In addition, we have followed cytomegalovirus (CMV) antigenemia (pp65) for CMV infection. Although some patients developed a positive antigenemia in the seropositive to negative donor-recipient combinations, only one patient had a prolonged febrile course for 1 week.

Diabetes Mellitus↗
PubMed1997

Tacrolimus rescue therapy for renal allograft rejection--five-year experience.

Over the 5 year period from 7/14/1989 until 5/24/1994, we have attempted graft salvage with tacrolimus conversion in a total of 169 patients (median age 33 years, range 2-75 years) with ongoing rejection on baseline CsA immunosuppression after failure of high dose corticosteroids and/or antilymphocyte preparations to reverse rejection. The indications for conversion to tacrolimus were ongoing, biopsy confirmed rejection in all patients. The median interval to tacrolimus conversion was 2 months (range 2 days to 55 months; mean 4.3+/-2.6 months) after transplantation. All patients had failed high dose corticosteroid therapy and 144 (85%) of the 169 patients had received at least one course of an antilymphocyte preparation plus high dose corticosteroid therapy prior to conversion. Twenty-eight patients (17%) were dialysis-dependent at the time of conversion owing to the severity of rejection. With a mean follow-up of 30.0+/-2.4 months (median 36.5 months, range 12-62 months), 125 of 169 patients (74%) have been successfully rescued and still have functioning grafts with a mean serum creatinine (SCR) of 2.3+/-1.1 mg/dl. Of the 144 patients previously treated with antilymphocyte preparations, 117 (81%) were salvaged. Of the 28 patients on dialysis at the time of conversion to tacrolimus, 13 (46%) continue to have functioning grafts (mean SCR 2.15+/-0.37 mg/dl) at a mean follow-up of 37.3+/-16.7 months. In the 125 patients salvaged, prednisone doses have been lowered from 28.0+/-9.0 mg/d (median 32, range 4-60 mg/d) preconversion to 8.5+/-4.1 mg/d (median 12 mg/d, range 2.5-20 mg/d) postconversion. Twenty-eight patients (22.4%) are currently receiving no steroids. This 5 year experience demonstrates that tacrolimus has sustained efficacy as a rescue agent for ongoing renal allograft rejection. Based on these data, we recommend that tacrolimus be used as an alternative to the conventional drugs used for antirejection therapy in renal transplantation.

Adolescent↗
PubMed1996

The use of tacrolimus in renal transplantation.

Tacrolimus (FK 506) is a novel immunosuppressive agent that has been in clinical use for solid organ transplantation since 1989. Early clinical trials of tacrolimus in liver, heart, kidney, lung, and intestinal transplantation at the University of Pittsburgh have demonstrated it to be a safe and effective agent with several potential advantages over existing immunosuppressive drugs. More recently, phase I and II multicenter trials of tacrolimus for renal transplantation have been performed; however, data are not yet available from these trials. Our experience with this drug has demonstrated excellent 1- and 2-year actuarial graft survival rates of 89% and 83%, respectively, in adult renal transplantation and 1- and 3-year graft survival rates of 98% and 85%, respectively in pediatric renal transplantation. A major advantage of tacrolimus noted in these trials was the ability to discontinue steroid therapy in approximately 50% of the patients. Tacrolimus has also shown efficacy as a rescue agent for renal allograft rejection failing conventional therapy in 74% of cases. This paper expands on these observations and focuses on the experience we have gained with the use of tacrolimus at our institution over the last 6 years.

Graft Survival↗
PubMed1994

FK506 "rescue" for resistant rejection of renal allografts under primary cyclosporine immunosuppression.

Seventy-seven patients with ongoing acute rejection on initial CsA therapy were converted to FK506 to attempt graft salvage. Fifty-nine patients had undergone primary transplantation and 18 had been retransplanted; there were 52 cadaveric and 25 living-donor transplants. The indications for conversion to FK506 were ongoing, biopsy-confirmed rejection in all patients, including vascular rejection in 20. The median interval to rescue was 2 months (range 2 weeks to 36 months) after transplantation. Sixty-one of the 77 patients (79%) had already received one or more courses of an antilymphocyte preparation (OKT3: n = 33; ALG or ATG: n = 1; OKT3+ALG/ATG: n = 27). Of the 77 patients, 57 (74%) have been successfully rescued and still have functioning grafts with a mean follow-up of 14 months, with a mean serum creatinine of 2.35 +/- 0.97 mg/dl. Eighteen patients were already dialysis-dependent at the time of conversion to FK506; of these, 9 (50%) were successfully salvaged and have a mean serum creatinine of 2.3 mg/dl. Of the 61 patients previously treated with antilymphocyte preparations, 48 (79%) were rescued. In those salvaged, prednisone doses have been lowered from 22.2 +/- 7.2 mg/day preconversion to 7.5 +/- 5.6 mg/day postconversion, and 12 patients are on FK506 monotherapy. In nondiabetics, mean serum glucose was 101.4 +/- 20.5 mg/dl preconversion and 93.2 +/- 22 postconversion (P = 0.07), uric acid 7.3 +/- 2.3 and 7.1 +/- 1.5 mg/dl (P = 0.53), and triglycerides 199.2 +/- 101.6 and 167.2 +/- 106.4 mg/dl (P = 0.06). Cholesterol levels were significantly lower following FK conversion (207.7 +/- 46.5 mg/dl pre. vs. 188.3 +/- 39.7 post., P = 0.007). FK506 is capable of salvaging renal allografts with ongoing acute rejection on CsA therapy, even when antilymphocyte preparations have been ineffective.

Adolescent↗
PubMed1992

Therapeutic use of ganciclovir for invasive cytomegalovirus infection in cadaveric renal allograft recipients.

Between November 1987 and September 1989, 419 cadaveric renal transplants were performed at our university. Of the patients 36 (8.6%) had invasive cytomegalovirus infection documented by gastric or duodenal mucosal biopsy in 23 (64%), bronchoalveolar lavage in 12 (33%), allograft biopsy or nephrectomy specimen in 5 (14%) and/or liver biopsy in 1 (3%). Cytomegalovirus severity was defined as mild in 27 patients, moderate in 6 and severe in 3. Ganciclovir [9-(1,3-dihydroxy-2-propoxymethyl)-guanine] was begun once the diagnosis was confirmed by histology or culture at a median of 56 days from transplantation (range 28 to 133 days). Duration of ganciclovir therapy was a minimum of 7 days or until fever was absent for 5 consecutive days (mean 12.2 +/- 3.5 days, range 4 to 21). Ganciclovir was well tolerated and side effects were limited to de novo neutropenia (7 patients), thrombocytopenia (2) and rash (1). Initial clinical improvement was observed in all patients. Two patients had recurrent cytomegalovirus infections that responded to a second course of ganciclovir. The 1-year actuarial patient survival was 100%. At a mean followup of 12.7 +/- 6.2 months 19 patients retained allograft function with a mean serum creatinine of 2.5 mg./dl. (range 1.2 to 4.6). Ganciclovir appears to be a safe and effective drug for the treatment of tissue invasive cytomegalovirus infection in cadaver renal transplant recipients. Prompt institution of this drug at diagnosis of invasive cytomegalovirus may lower the mortality rate formerly associated with this disease.

Adolescent↗
PubMed1992

Renal transplantation in patients 65 years old or older.

Between January 1982 and August 1989, cadaveric renal transplantation was performed in 22 patients 65 years old or older. Mean recipient age was 68 years (range 65 to 73 years). There were 17 men and 5 women. Additional risk factors included retransplantation (3 patients), high (greater than 30%) panel reactive antibody (4) and diabetes (1). All patients received cyclosporine as part of the immunosuppressive regimen. The 3-year actuarial patient and allograft survival rates were 89% and 71%, respectively. There were 6 graft losses due to chronic rejection (2 patients), renal vein thrombosis (1), myocardial infarction (1), withdrawal of immunosuppression because of sepsis (1) and primary nonfunction (1). Of the 16 patients with a functioning graft 12 currently have a serum creatinine of less than 2.0 mg./dl. These results suggest that cadaveric renal transplantation is an acceptable form of treatment for patients older than 65 years with end stage renal disease.

Age Factors↗
PubMed1991

Highly sensitized patients with delayed graft function: a management protocol.

The postoperative management of the highly sensitized renal transplant recipient with delayed graft function on cyclosporine is complicated. Allografts with delayed graft function are reported to have a 20 to 30% poorer 1-year survival than allografts without delayed graft function. Several factors may be implicated in this poorer 1-year survival. A decrease in or cessation of cyclosporine dosage frequently is used in an attempt to minimize nephrotoxicity. Such under-immunosuppression can result in irreversible rejection. Occasionally, a pessimistic view of the prognosis for the transplant may result in early abandonment of the allograft with discontinuation of immunosuppression and allograft nephrectomy. We report on 3 highly sensitized patients whose kidneys had delayed graft function and were deliberately maintained on high doses of cyclosporine throughout the period of delayed graft function. Each graft achieved function (2, 4 and 5 months) after transplantation. The serum creatinine levels 20, 28 and 38 months after transplantation were 2.7, 2.0 and 1.0 mg./dl., respectively. We suggest that the maintenance of high cyclosporine levels throughout the delayed graft function period is useful in highly sensitized recipients and was an important factor in their successful outcome. A management protocol for such patients is proposed.

Adolescent↗