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ABSTRACT: Mammalian target of rapamycin (mTOR) inhibition has been associated with gonadal dysfunction. The aim of this study was to characterize the effect of sirolimus (SRL) on male gonadal function in an experimental model.
Male Wistar rats were treated with intraperitoneal administration of vehicle or SRL. Vehicle group was treated for 12 weeks. Rats treated with SRL were killed at 4, 8, and 12 weeks. A group of rats was treated with SRL for 4 weeks and then observed during 8 weeks to analyze the possible reversibility of the effect of mTOR inhibition. Body and testicular weight, testosterone, follicle-stimulating hormone level, and luteinizing hormone level were measured and testicular histology was analyzed including proliferation and apoptosis analysis.
Testicular weight was significantly lower in all SRL groups. After SRL withdrawal testicular weight had partially recovered. The expression of steroidogenic acute regulatory protein decreased during SRL treatment, which could explain the reduction of testosterone levels, because steroidogenic acute regulatory protein is crucial for testosterone synthesis. Spermatogenesis was blocked on the spermatogonial level by SRL treatment. Withdrawal of SRL treatment led to complete recovery.
mTOR inhibition in healthy animals produces sexual hormone dysfunction, seminiferous tubule dystrophy and spermatogenesis blockade. Furthermore, the spermatogenesis blockade produced by SRL is reversible.
Transplantation 02/2012; 93(9):874-9. · 4.00 Impact Factor
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ABSTRACT: The use of mammalian target of rapamycin inhibitor (mTOR-I) after kidney transplantation has been associated with a higher incidence of proteinuria compared with calcineurin inhibitors (CNIs). This review will focus on mTOR-I-associated proteinuria in different settings after kidney transplantation: de novo mTOR-I treatment in combination with CNI, de novo mTOR-I-containing and CNI-free treatment, early conversion from a CNI-based regimen to an mTOR-I-based regimen, and late conversion. Some possible mechanisms of mTOR-I-induced proteinuria will also be reviewed.
Transplantation reviews (Orlando, Fla.) 01/2012; 26(1):27-9.
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ABSTRACT: Anaemia and microcytosis are common post kidney transplantation. The aim of this study was to evaluate the potential role of mammalian target of rapamycin (mTOR) inhibition in the development of anaemia and microcytosis in healthy animals and in human erythroid cultures in vitro.
Rats with normal kidney function were treated with sirolimus (n = 7) or vehicle (n = 8) for 15 weeks. Hemograms were determined thereafter. In the sirolimus withdrawal part of the study, rats received sirolimus (SRL) for 67 days (n = 4) 1 mg/kg three times per week or for 30 days (n = 4) and were observed until Day 120. Hemograms were performed regularly. Peripheral blood mononuclear cells from healthy controls (HC; n = 8), kidney transplant patients with sirolimus treatment with (SRL + MC; n = 8) or without microcytosis (SRL - MC; n = 8) were isolated and cultured in the absence or presence of SRL (5 ng/mL).
SRL-treated animals had a reduced mean corpuscular volume (MCV) and elevated erythrocyte count compared with control animals after 15 weeks of treatment. This effect was evident as early as 4 weeks (MCV: 61.5 ± 1.8 versus 57 ± 1.7 fL; P = 0.0156; Red blood count 7.4 ± 0.3 × 10(9)/L versus 8.6 ± 0.5 × 10(9)/L; P = 0.0156) and was reversible 90 days after SRL withdrawal. SRL in the culture medium of erythroid cultures led to fewer colonies in cultures from HC as well as from kidney transplant patients (without SRL: 34.2 ± 11.4 versus with SRL: 27.5 ± 9.9 BFU-E-derived colonies P = 0.03), regardless if the cultures were derived from recipients with normocytic or with microcytic erythrocytes. The presence of tacrolimus in the culture medium had no influence on the number and size of colonies.
mTOR inhibition induces microcytosis and polyglobulia, but not anaemia in healthy rats. This might be caused by growth inhibition of erythroid precursor cells.
Nephrology Dialysis Transplantation 07/2011; 27(2):537-41. · 3.40 Impact Factor
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ABSTRACT: In the course of the influenza A H1N1 pandemic, transplanted patients were recommended to receive vaccination. In the present study, we evaluated the immune response to an adjuvanted influenza A H1N1 vaccine (Pandemrix®) in renal allograft recipients.
Sixty patients and 22 healthy controls participated in a prospective observational study and received a single dose of Pandemrix®. H1N1 antibody titres as well as anti-HLA antibodies were determined before and after vaccination. In 19 patients, a booster vaccination was performed and the outcome of all vaccinated renal allograft recipients (n = 107) in our clinic was reviewed.
Two out of sixty patients had an elevated influenza A H1N1 titre before vaccination. Of the remaining 58 patients, only 20/58 (34.5%) developed a protective immune response in contrast to 20/22 (91%) of the control group. After booster vaccination, a protective titre was present in 8/19 (42%) of patients. Of the 107 patients, 6 (5.6%) developed new donor-specific HLA antibodies after vaccination.
These data suggest that Pandemrix® does not provide a protective immune response in the majority of kidney transplant recipients. Therefore, for new vaccines, efficacy as well as safety profiles should be evaluated in this subgroup of patients.
Nephrology Dialysis Transplantation 05/2011; 27(1):423-8. · 3.40 Impact Factor
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ABSTRACT: Background and objective: The clinical manifestation of angioedema ranges from minor facial edema up to life-threatening swelling of mouth and throat. Hereditary defects, drugs, and food allergies may play a role in the development of angioedema. We systematically investigated the incidence of angioedema in renal allograft recipients treated with mTOR inhibitors (mTORis).
All patients in the authors' electronic database who had received mTORis (n = 309) between 2000 and 2008 were identified. Of these, 137 were additionally treated with angiotensin-converting enzyme inhibitors (ACEis).
Nine patients (6.6%, 3.8 per 100 treatment years) developed angioedema after a mean period of 123 days under combined therapy with mTORi and ACEi. Among the remaining 172 patients on mTORi, including 119 patients treated with angiotensin-receptor blockers, only two developed angioedema (1.2%, 0.5 per 100 treatment years, P = 0.01). In patients receiving mycophenolate and ACEi (n = 462), 10 instances of angioedema were found (2.1%, 0.8 per 100 treatment years, P = 0.004).
This systematic investigation demonstrated a noticeable incidence of 6.6% angioedema under combined therapy with mTORi and ACEi in kidney transplant recipients. Treatment with either ACEi or mTORi alone resulted in a significantly lower incidence of angioedema, suggesting that this combination should be avoided.
Clinical Journal of the American Society of Nephrology 04/2010; 5(4):703-8. · 5.23 Impact Factor
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Elisenda Bañón-Maneus, Fritz Diekmann,
Montserrat Carrascal,
Luis F Quintana,
Daniel Moya-Rull,
Monica Bescós,
Maria J Ramírez-Bajo,
Jordi Rovira,
Alex Gutierrez-Dalmau,
Amanda Solé-González,
Joaquin Abián,
Josep M Campistol
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ABSTRACT: Despite advances in therapeutics, graft loss associated with chronic allograft dysfunction (CAD) remains high. Urinary proteomic analysis is a noninvasive method that could be used to detect and evaluate CAD in renal transplant recipients. This study was aimed to establish the normal proteome map of stable transplant patients and to validate the utility of two-dimensional difference gel electrophoresis (2DE-DIGE) in identifying new candidates as urinary biomarkers of CAD.
Morning spot urine samples that were collected from kidney transplant recipients with biopsy-proven interstitial fibrosis and tubular atrophy (IFTA) stages 0-I-II/III (n=8/group) under immunosuppressive treatment with tacrolimus plus mycophenolate with or without prednisone. 2DE silver staining and mass spectrometry analyses were used to establish the normal proteome map, and 2DE-DIGE and mass spectrometry were used to identify proteins exhibiting differential abundance.
This study defines the normal proteome of stable renal transplant patients, which is composed of several plasma proteins, as well as of immunologic proteins that are probably specific to transplant recipients. The 2DE-DIGE study showed 19 proteins with differential concentrations, depending on the IFTA histologic score. These 19 proteins could be used as urinary biomarkers of the severity of IFTA in renal transplant recipients.
Transplantation 03/2010; 89(5):548-58. · 4.00 Impact Factor
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Jordi Rovira,
Edgar M Arellano,
Joaquim Carreras,
Begoña Campos,
Barbara Vodenik,
Elisenda Bañón-Maneus,
María José Ramírez-Bajo,
Daniel Moya-Rull,
Amanda Solé-González,
Astrid Hernández,
Ignacio Revuelta,
Luis F Quintana,
William J Howat,
Josep M Campistol, Fritz Diekmann
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ABSTRACT: Sirolimus (SRL) is a potent and specific immunosuppressive drug used in organ transplantation, as basic therapy or in combination with calcineurin inhibitors. Although SRL is a nonnephrotoxic drug, many reports have related its use with the development of proteinuria, especially after conversion. Therefore, the aim of this study was to elucidate the interrelation between early and late SRL administration on the development of glomerular hypertrophy and proteinuria in a model of renal mass reduction (RMR).
Rats underwent 2/3 cryoablation of the left kidney and subsequent right nephrectomy (n=42) or sham operations (n=29). Two weeks before (early study) or 12 weeks after (late study) surgery, SRL or vehicle was administered three times weekly. Creatinine clearance and proteinuria were determined throughout the study, and a complete histologic analysis was performed at the end of the study.
Treatment with SRL had no effect on creatinine clearance, independently of the administration time. Four weeks after RMR, a significant increase in proteinuria was observed. Proteinuria was stabilized after early and late SRL administration, whereas vehicle-treated animals showed a further increase in proteinuria. Glomerular hypertrophy was strongly associated with proteinuria, and early SRL introduction prevented glomerular enlargement. The histologic analysis showed less structural damage in the two groups of animals treated with SRL than in the control group.
Although early SRL introduction blocked glomerular hypertrophy, SRL treatment revealed the potential to halt progression of proteinuria and histologic damage at any time of administration in a model of RMR.
Transplantation 10/2009; 88(5):646-52. · 4.00 Impact Factor
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ABSTRACT: The aim of this study was to retrospectively evaluate safety and feasibility of sirolimus (SRL) monotherapy in kidney transplant recipients. Patients older than 18 years, with monotherapy prescribed for more than 1 month and at least 6 months of follow-up were included. We analysed the data from 138 patients. Mean time period between transplantation and start of monotherapy was 6.5 +/- 4.1 years.The most frequent reason was minimization of immunosuppression followed by malignancy. Acute rejection rate was 1.4% at 12 months (two episodes). Graft and patient survival were 94.2% and 97.1% respectively. Mean follow-up after initiation of monotherapy was 29.4 months. Two patients died as a result of cardiovascular diseases and two because of malignancy. Percentage of withdrawal from monotherapy was 14%. SRL trough levels were 10.2 +/- 2.3 ng/ml at baseline and 9.6 6 +/- 3.3 ng/ml at 12 months. Mean glomerular filtration rate was 48.4 ml/min/1.73 m(2) at baseline and 47.7 ml/min/1.73 m(2) at 12 months. Proteinuria was 499.7 mg/24 h at baseline and 543 +/- 794 mg/24 h at 12 months. No significant changes in lipids, glucose, or hemoglobin occurred, although the percentage of patients treated with statins and Epo increased at the end of the follow-up. SRL monotherapy is suitable as long-term immunosuppression in selected patients with no significantly increased risk of late acute rejection.
Transplant International 10/2009; 23(3):307-12. · 2.92 Impact Factor
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ABSTRACT: m-TOR inhibitors (e.g. sirolimus) are well-tolerated immunosuppressants used in renal transplantation for prophylaxis of organ rejection, and are associated with long-term graft survival. Early use of sirolimus is often advocated by clinicians, but this may be associated with a number of side-effects including impaired wound-healing, lymphoceles and delayed graft function. As transplant clinicians with experience in the use of sirolimus, we believe such side-effects can be limited by tailored clinical management. We present recommendations based on published literature and our clinical experience. Furthermore, guidance is provided on sirolimus use during surgery, both at transplantation and for subsequent operations.
Transplant International 05/2009; 22(7):681-7. · 2.92 Impact Factor
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ABSTRACT: Despite optimal immunosuppressive therapy, more than 50% of kidney transplants fail because of chronic allograft dysfunction. A noninvasive means to diagnose chronic allograft dysfunction may allow earlier interventions that could improve graft half-life. In this proof-of-concept study, we used mass spectrometry to analyze differences in the urinary polypeptide patterns of 32 patients with chronic allograft dysfunction (14 with pure interstitial fibrosis and tubular atrophy and 18 with chronic active antibody-mediated rejection) and 18 control subjects (eight stable recipients and 10 healthy control subjects). Unsupervised hierarchical clustering showed good segregation of samples in groups corresponding mainly to the four biomedical conditions. Moreover, the composition of the proteome of the pure interstitial fibrosis and tubular atrophy group differed from that of the chronic active antibody-mediated rejection group, and an independent validation set confirmed these results. The 14 protein ions that best discriminated between these two groups correctly identified 100% of the patients with pure interstitial fibrosis and tubular atrophy and 100% of the patients with chronic active antibody-mediated rejection. In summary, this study establishes a pattern for two histologic lesions associated with distinct graft outcomes and constitutes a first step to designing a specific, noninvasive diagnostic tool for chronic allograft dysfunction.
Journal of the American Society of Nephrology 01/2009; 20(2):428-35. · 9.66 Impact Factor
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Jordi Rovira,
Edgar Marcelo Arellano,
James T Burke,
Yves Brault,
Daniel Moya-Rull,
Elisenda Bañón-Maneus,
María J Ramírez-Bajo,
Alex Gutiérrez-Dalmau,
Ignacio Revuelta,
Luis F Quintana,
Josep M Campistol, Fritz Diekmann
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ABSTRACT: The aim was to study the influence of sirolimus (SRL) on body weight in a rat model and in kidney transplant patients. Wistar rats (15 weeks old) were either treated with vehicle (VEH; n = 8) or SRL (n = 7) 1.0 mg/kg three times per week for 12 weeks. Body mass and food intake were measured weekly. Adipocyte diameter was determined in hematoxylin-eosin stains. The body mass index (BMI) obtained from clinical kidney transplant trials comparing SRL-based with cyclosporine-based therapy was analyzed. Animals: SRL produced a decrease of the weight gain curve. At the end of the study, mean body weight in the SRL group was lower than in the VEH group (356 vs. 507 g, P < 0.01) in spite of comparable food intake normalized for body weight was not different. Mean adipocyte diameter was 36 mum in VEH and 25 mum in SRL rats (P = 0.009). Mean SRL blood trough concentration was 38 ng/ml. Kidney transplant patients: Two years after transplantation, BMI was significantly lower in the SRL-based treatment arm compared to cyclosporine (24.17 +/- 2.99 vs. 25.97 +/- 5.01 kg/m(2), P = 0.031). SRL treatment leads to less body mass. Adipocyte cell diameter was reduced in SRL-treated animals. A possible explanation may be the effects of SRL on metabolic regulation and cell growth.
Transplant International 10/2008; 21(10):992-8. · 2.92 Impact Factor
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Stephanie Krämer,
Yingrui Wang-Rosenke,
Valeska Scholl,
Eva Binder,
Tanja Loof,
Dmytro Khadzhynov,
Hiroshi Kawachi,
Fujio Shimizu, Fritz Diekmann,
Klemens Budde,
Hans-H Neumayer,
Harm Peters
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ABSTRACT: Treatment options in human mesangioproliferative glomerulonephritis/sclerosis, mostly IgA nephropathy, are limited. Progressive mesangioproliferative nephropathy represents a major cause of end-stage kidney disease. The present study explores the efficacy of low-dose mTOR inhibition by rapamycin in a chronic-progressive model of mesangioproliferative glomerulosclerosis (cGS). cGS was induced by high-dose anti-thy1 antibody injection into uninephrectomized rats. Rapamycin administration (2.5 mg.kg(-1).body wt(-1)) was started 10 days after antibody injection and continued until week 20. cGS was characterized by advancing proteinuria, increased blood pressure, marked tubulointerstitial and glomerular fibrosis, cell proliferation and round cell infiltration, and impaired renal function. Kruskal-Wallis and Mann-Whitney U-tests were used for statistical analysis. The course of chronic anti-thy1-induced glomerulosclerosis was significantly attenuated by low-dose rapamycin treatment. In week 20, this was demonstrated by improvements in proteinuria (-38%), systolic blood pressure (-16 mmHg), tubulointerstitial and glomerular histological matrix accumulation (-61 and -24%), transforming growth factor-beta1 overexpression (-41 and -47%), collagen I deposition (-53 and -65%), cell proliferation (-90 and -76%), and leukocyte number (macrophages -52 and -53%; lymphocytes -58 and 51%), respectively. Rapamycin improved renal function as well (blood creatinine -0.68 mg/dl, urea -66.7 mg/day, and creatinine clearance +0.13 ml.min(-1).100 g body wt(-1)). In conclusion, low-dose mTOR inhibition by rapamycin limits the progressive course of anti-thy1-induced renal disease toward chronic glomerulosclerosis, tubulointerstitial fibrosis, and renal insufficiency. Renoprotection by rapamycin involved significant beneficial effects on multiple key pathways in the progression of chronic renal disease, i.e., proteinuria, extracellular matrix accumulation, renal cell proliferation, and inflammatory cell infiltration.
American journal of physiology. Renal physiology 03/2008; 294(2):F440-9. · 3.68 Impact Factor
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ABSTRACT: The aim was to evaluate long-term graft survival and function after conversion to sirolimus (SRL) for chronic calcineurin inhibitor (CNI) toxicity and the predictive value of baseline proteinuria. This is a follow-up conversion study of 59 renal transplant patients with deteriorating graft function and histologic signs of CNI toxicity. Previously, baseline proteinuria <800 mg/day was identified as a short-term predictor for successful conversion. Follow-up was 5.3 +/- 0.8 (3.7-6.8) years. Patient survival was 88%, graft survival 38%. Creatinine clearance at the last follow-up was 33.7 +/- 14 ml/min, proteinuria 826 +/- 860mg/day. Baseline proteinuria <800 mg/day was associated with better graft survival. In a cox analysis including proteinuria >800 mg, glomerular filtration rate, age at conversion, chronic Banff score at conversion and time after transplantation at conversion, higher proteinuria was associated with a relative risk of graft loss of 3.98. Prognosis of chronic allograft dysfunction is poor. However, conversion to SRL remains an option for patients with low baseline proteinuria, which can slow down deterioration of graft function during a follow-up period of up to 5 years.
Transplant International 02/2008; 21(2):152-5. · 2.92 Impact Factor
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ABSTRACT: The reflex sympathetic dystrophy syndrome (RSDS) in organ transplant recipients has only previously been reported in patients treated with calcineurin inhibitors. We retrospectively analyzed 393 renal transplant patients treated with sirolimus, 9 of whom developed RSDS. All the patients reported varying degrees of pain in the legs, affecting the knees, ankles, and/or feet, plus cutaneous erythema. The onset of pain ranged from 1-6 months after transplantation. At the time of diagnosis of RSDS, the mean serum creatinine was 1.4 mg/dL (range 1.0-1.7) and bone scintigraphy with 99mTc pyrophosphate showed increased uptake in all cases. The symptoms remitted 3-10 months after treatment (mean, 4 months) with calcitriol, with or without nifedipine or calcitonin, and in one case with suppression of sirolimus. We conclude that sirolimus therapy may induce RSDS in renal transplant recipients.
Transplantation 02/2008; 85(2):290-2. · 4.00 Impact Factor
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ABSTRACT: Many kidney transplant patients experience an increase in proteinuria when converted from a calcineurin inhibitor-based regimen to one based on a mammalian target of rapamycin (mTOR) inhibitor, and preexisting proteinuria and poor renal function have been identified as risk factors for this increase. Our aim was to evaluate the effect of sirolimus, an mTOR inhibitor, on renal function and histology in a proteinuric model of reduced renal mass. Sirolimus-treated animals had approximately half as much proteinuria as vehicle-treated animals (P < 0.05), and had less glomerulosclerosis, tubular atrophy, interstitial fibrosis, and inflammation. Immunohistochemistry showed that sirolimus attenuated the increased expression of renal vascular endothelial growth factor (VEGF), as well as the expression of VEGF receptors 1 and 2. In conclusion, sirolimus halted the progression of proteinuria and structural damage in a rat model of reduced renal mass, possibly through a reduction in renal VEGF activity.
Journal of the American Society of Nephrology 10/2007; 18(10):2653-60. · 9.66 Impact Factor
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Fritz Diekmann,
Josep M Campistol,
Núria Saval,
Alex Gutiérrez-Dalmau,
Edgar M Arellano,
Marta Crespo,
Esther Rossich,
Núria Esforzado,
Federico Cofán,
María José Ricart,
José Vicente Torregrosa,
Federico Oppenheimer
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ABSTRACT: The aim was to evaluate feasibility and safety of calcineurin inhibitor-free immunosuppression in high-risk donor kidney transplantation with sequential sirolimus introduction. Kidney transplant patients (n=76) with a donor aged >60 years, donor with acute renal failure, or a nonheartbeating donor were included. Immunosuppression consisted of antithymocyte globulin or basiliximab, mycophenolate mofetil, prednisone, and sequential introduction of sirolimus. One-year patient survival was 96.2% and 95.8%; graft survival was 94.2% and 91.7%; acute rejection rates were 21.2% and 12.4%; delayed graft function was 21.2% and 66.7%; and creatinine clearance was 58+/-20 mL/min and 56+/-21 mL/min for the brain-dead donor group and the nonheartbeating donor group, respectively. Most adverse events were infections, but also three lymphoceles, three urinary fistulas, three wound seromas. Sequential sirolimus introduction in high-risk donor kidney transplantation was found to lead to good patient and graft survival and incidence of acute rejection and delayed graft function.
Transplantation 08/2007; 84(3):429-32. · 4.00 Impact Factor
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Fritz Diekmann,
Alex Gutiérrez-Dalmau,
Sonia López,
Federico Cofán,
Núria Esforzado,
María José Ricart,
Esther Rossich,
Núria Saval,
José Vicente Torregrosa,
Federico Oppenheimer,
Josep M Campistol
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ABSTRACT: The contribution of mammalian target of rapamycin (mTOR) inhibitors to proteinuria is controversial. The aim was to analyse proteinuria in suboptimal kidney calcineurin inhibitor-(CNI) free de novo immunosuppression.
All patients from our centre with donors >60 years and CNI-free treatment were included (n = 108). Patients were divided into two groups: (i) SRL group: sirolimus (SRL) + prednisone + mycophenolate mofetil (MMF) + antiCD25; (ii) MMF group: prednisone + MMF w/ or w/o antiCD25 (n = 75). Follow-up was 12 months.
Donors were slightly younger in the SRL group (68 vs 71 years; P < 0.05), receptor age (67 vs 65 years) was not significantly different. Patient survival in the MMF group was 88 vs 94% in the SRL group, however, these differences did not reach statistical significance. One-year graft survival censored for death was 83% in the MMF group and 94% in the SRL group. Acute rejection rate was 45% in the MMF and 15% in the SRL group (P < 0.01). The incidence of CNI introduction was higher in the MMF-group (35 vs 5; P < 0.05). The intention-to-treat analysis revealed significant differences of proteinuria [SRL vs MMF at 12 months: 461 (163-6988) vs 270 (53-3029) mg/day], which did not exist in the on-therapy (OT) analysis [SRL vs MMF at 12 months: 357 (199-1428) vs 279 (53-3029) mg/day]. New onset nephrotic range proteinuria seemed to occur slightly more frequently in SRL patients (3/33 vs 1/75; P = 0.049), however, all four cases occurred in a context of recurrent disease, or previous drug-independent damage or non-adherence. All of these patients were converted to CNI.
SRL-based compared with MMF-based treatment in kidney transplantation with advanced age donors is associated with an acceptable outcome, however, with increased proteinuria in the intention-to-treat analysis. A large subgroup of the patients in the MMF group experienced acute rejection and required conversion to CNI.
Nephrology Dialysis Transplantation 08/2007; 22(8):2316-21. · 3.40 Impact Factor
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ABSTRACT: Daily bisphosphonate is effective in preventing and treating corticosteroid-induced osteoporosis in renal transplant recipients, although it frequently has gastrointestinal side effects. The aim was to assess efficacy and side effect profile of weekly oral risedronate. Eighty-four renal transplant patients, receiving either cyclosporin A or tacrolimus and steroids were prospectively included. The study group (39 patients) received 35 mg risedronate weekly, vitamin D and calcium, while control group (45 patients) only vitamin D and calcium. At baseline, 6 and 12 months, creatinine, calcium, phosphorus, alkaline phosphatase and iPTH were determined. Fractures and bone mineral densities were assessed by X-rays and dual-energy X-ray absorptiometry, respectively. Pain was assessed by clinical interview. Mineral bone density score increased significantly in risedronate group after 1 year. There were no differences in the incidence of fractures, although, anamnestic pain assessment revealed that 3% of treatment group reported to have bone pain compared with 18% in nontreatment group (P < 0.05). Follow-up calcium, phosphorus, alkaline phosphatases, and iPTH levels showed no differences from basal measures. Risedronate was well tolerated with no major side effects. Weekly oral risedronate in renal transplanted patients reduces bone mineral loss and bone pain and has an excellent side effect profile.
Transplant International 08/2007; 20(8):708-11. · 2.92 Impact Factor
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ABSTRACT: Sirolimus is an agent with lymphocyte-specific features similar to those of calcineurin inhibitors but with a different mechanism of action and safety profile. To optimize the use of sirolimus-based immunosuppression, further investigation of appropriate pharmacokinetic (sirolimus exposure) and pharmacodynamic (sirolimus T-cell immunomodulator effect) monitoring is required to determine personalized target concentrations.
The main objective of the study was to evaluate the feasibility and reproducibility of combined pharmacokinetic and pharmacodynamic monitoring and to apply biomarkers of immunosuppression in stable kidney transplant recipients receiving sirolimus monotherapy.
Fourteen renal transplant patients treated with sirolimus monotherapy (median 2 years) were included in this study. Pharmacokinetic and pharmacodynamic parameters were evaluated in each patient three times: at inclusion in the study (day 1), then again at 3 and 6 months.
The median sirolimus concentration was 11.5 ng/mL. CD4+ T-cell adenosine triphosphate (ATP) concentrations (150 ng/mL) and interleukin (IL)-10 production (50.9 ng/mL) were significantly lower in treated patients than in healthy controls (n = 95) [301 ng/mL; 278 ng/mL, respectively]. Median inhibition of T-cell proliferation was 60% (31-96%) in treated patients. Interferon-gamma and transforming growth factor-beta production was found to be similar to those in the healthy controls. Our results suggest an association between low ATP and IL-10 concentrations and the presence of infection.
The sequential measurement of these biomarkers in stable renal transplant recipients treated with monotherapy could be useful to evaluate the biological effect of sirolimus in each patient and to establish personalized therapy taking into account the individual response to the drug.
Molecular diagnosis & therapy 02/2007; 11(4):247-56. · 1.71 Impact Factor
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ABSTRACT: To evaluate the effect of intensive fetal surveillance via Doppler ultrasound and fetal non-stress test on the perinatal outcome of pregnant women undergoing an intensified hemofiltration scheme.
Five consecutive pregnancies of women undergoing intensified hemodialysis were analyzed due to the following parameters: maternal background, hemodialysis schedule during pregnancy, blood pressure, occurrence of fetal complications, occurrence of obstetric complications, gestational week at delivery, mode of delivery, and newborn outcome and follow-up.
All pregnancies resulted in a live birth, mean gestational age was 32 weeks. Intrauterine growth restriction occurred in 4 fetuses, pathological umbilical artery flow velocity waveforms in 2. The mean birth weight was 1,764 g (range 1,274-2,465 g). Cesarean section was performed in 3 patients because of fetal distress. None of the patients developed severe complications like pre-eclampsia.
Although intensified dialysis enables the maintenance of stable uteroplacental and fetal perfusion, intensive fetal monitoring is mandatory to reduce perinatal morbidity and mortality in pregnant women on maintenance dialysis.
Fetal Diagnosis and Therapy 02/2007; 22(4):289-93. · 1.05 Impact Factor