S Zárraga

Hospital de Cruces, Bilbo, Basque Country, Spain

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Publications (29)80.78 Total impact

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    ABSTRACT: Kidney transplantation (KT) outcomes in human immunodeficiency virus (HIV)-infected recipients are under continuous research. High incidence of early post-transplant complications such as acute rejection has been observed. A multicenter study including HIV-infected patients who underwent KT in Spain, from 2001 to 2011, was performed. The study population included 108 recipients, 36 HIV-infected, and 72 matched HIV-negative KT recipients. HIV-infected recipients developed more delayed graft function (DGF) (52% vs. 21%, P < 0.001). One- and 3-year graft survival was 91.6% and 86.2% in HIV-infected patients, and 97.1% and 94.7% in HIV-negative patients (P = 0.052). In two-variate Cox analysis, HIV infection was not a predictor of graft loss after adjusting for time on dialysis, acute rejection, and DGF. Multivariate analysis for DGF revealed HIV-positive status as independent risk factor. We analyzed the evolution of immunosuppressive and antiretroviral therapy (ART). In HIV-infected patients tacrolimus trough levels were very high in the first week and significantly lower in the second week post-transplant (P = 0.042). Post-transplant ART was significantly changed: protease inhibitors use decreased (P = 0.034) and integrase inhibitor use increased (P < 0.001). DGF is another frequent early complication in HIV-infected recipients that can affect graft survival. Strategies to prevent DGF and antiretroviral regimes with less drug interactions could improve outcomes.
    Transplant International 06/2013; · 3.16 Impact Factor
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    ABSTRACT: The increasing number of elderly people eligible for solid organ transplants has made it necessary to reevaluate how the decline in immune function associated to ageing (immunosenescence) affects solid organ transplants. Some immunosenescence biomarkers, such as the expansion of CD28(-)CD8+ T lymphocytes, have been associated to cytomegalovirus infection and are related to a form of accelerated immune senescence in transplant recipients. However, the impact of cytomegalovirus replication on downregulation of CD28 on total CD8+ T cells is independent of patients' age, whereas downregulation on cytomegalovirus-specific CD8+ T cells depends on patients' age, inducing early immunosenescence of cytomegalovirus-specific CD8+ T cells in young but not elderly solid organ transplants recipients. Although immunosenescence in transplant recipients should be considered a two-edged sword as it is a risk factor for the development of tumors after transplantation, it has a beneficial effect in attenuating acute allograft rejection and correlates with better clinical outcomes.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 05/2012; · 4.31 Impact Factor
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    ABSTRACT: Proteinuria is a marker of poor prognosis in kidney transplant recipients as well as in nontransplant patients with chronic kidney disease. It negatively influences the rate of deterioration of graft renal function, graft survival, and more importantly, patient survival. This review analyzes the current knowledge on the management of this crucial aspect in kidney transplantation. The reduction of proteinuria has demonstrated a beneficial effect on kidney function and also on patient survival in nontransplant patients with chronic kidney disease, but unfortunately, to date, it has not been possible to demonstrate the same benefit in the kidney transplant population (although it probably exists). Nevertheless, the appearance of proteinuria in a renal transplant patient must always be followed by an investigation on its etiology, and many times, it should include a graft biopsy to adequately categorize the underlying process responsible for the proteinuria and to establish a correct therapy. Furthermore, in spite of the cause of proteinuria, it should be treated to reduce to normal or near-normal levels with the objective to eliminate or reduce its negative effects on the graft and the cardiovascular system of the patient. The drugs that interfere with the renin-angiotensin-aldosterone system, angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers, are the cornerstone of the management of this complication, and recently, direct renin inhibitors have added to the armamentarium. Mono-, dual-, and triple-therapy modalities are discussed, as well as other therapies and nonpharmacologic measures.
    Transplantation reviews (Orlando, Fla.) 01/2012; 26(1):36-43.
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    ABSTRACT: The shortage of organ availability in recent years has made it necessary to use grafts from advanced-aged donors to maintain the rate of renal transplantation in our country. The objective of this study was to evaluate the graft function and patient survival using kidneys from deceased donors of over 65 year of age. From 2005 until 2010, we compared the outcomes of patients who received grafts from donors over 65 years old vs less than 65 years. We observed no significant difference in sex, time on dialysis, or cold ischemia time between the groups. As expected the recipient age was significantly different. For the analysis of survival, we used the Tablecloth-Haenzel test and the Kaplan-Meier survival estimator. Actuarial survivals at 3 years after transplantation showed 84.8% among patients transplanted with kidneys from donors over 65 years old versus 97.5% in the control group. The graft survival was 78.8% among expanded criteria versus 86.85% in the control group. When we analyzed graft survival using an "exitus-censured" analysis, we obtained graft survivals of 89.1% in the expanded criteria kidney group versus 88.6% among the controls. We concluded that the use of kidney from donors over 65 years of age allows us to increase the rate of renal transplantation to about 15 to 20 per million population, with good graft and patient survivals provided that the protocol for expanded criteria organs ensured proper macroscopic and microscopic evaluation of the organ for transplantation.
    Transplantation Proceedings 11/2011; 43(9):3340-3. · 0.95 Impact Factor
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    ABSTRACT: Prolonged-release tacrolimus was developed to provide a more convenient once-daily dosing that could improve patient adherence. We conducted a multicenter, prospective, observational, 12-month study to describe the efficacy, safety and patient preference of conversion from tacrolimus twice-daily to once-daily formulation in stable kidney transplant recipients in routine clinical practice. Conversion was made on a 1 mg: 1 mg basis (1 mg: 1.1 mg in patients with trough levels <6 ng/mL). The study included 1832 patients (mean age (± SD): 50.0 ± 13.4 years; 62.7% male). After conversion, a modest reduction in tacrolimus trough levels, necessitating an increase in daily dose, was observed (mean changes at 12 months of -9.1% and +1.24%, respectively; p < 0.0001). Mean glomerular filtration rate did not change significantly (56.5 ± 19.7 mL/min at conversion vs. 55.7 ± 20.6 mL/min at 12 months). Proteinuria, blood pressure, lipid, hepatic and glucose parameters remained stable. Eight patients (0.4%) had acute rejection and 34 patients (1.85%) discontinued treatment. Almost all patients (99.4%) preferred the once-daily formulation, because of less frequent dosing (66%) and improved adherence (34%). In conclusion, at similar doses to twice-daily tacrolimus, once-daily formulation provided stable renal function, a low acute rejection rate, and good tolerability in stable kidney transplant recipients in the routine clinical practice setting.
    American Journal of Transplantation 06/2011; 11(9):1965-71. · 6.19 Impact Factor
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    ABSTRACT: Some aspects of kidney transplant outcome in human immunodeficiency virus (HIV)-infected patients are still controversial. Besides, published experience is scarce in Europe. A multicentre case-control study was designed to analyse the outcome of renal transplant in HIV + patients in Spain. Twenty HIV + patients were compared with a matched cohort of 40 HIV - recipients. Post-transplant follow-up period was 39.98 ± 36.51 months. Pre-transplant dialysis duration and the incidence of pre-transplant opportunistic infections were significantly higher for HIV + patients. Following transplantation, HIV + recipients presented lower incidence of immediate renal function and more acute rejection. Graft survival was lower although the difference was not significant (1 year: 85 vs 97.5%; 5 years: 74.4 vs 91%; log-rank P = 0.058). There was no difference in patient survival rates. Eight patients in each group presented hepatitis C (HCV) infection. Coinfected patients were compared with HIV +/HCV - and HIV -/HCV + recipients. Coinfected patients presented more time on dialysis, greater duration of delayed graft function and lower graft survival (HIV +/HCV + vs HIV +/HCV -: log-rank P = 0.009; HIV +/HCV + vs HIV -/HCV +: log-rank P = 0.02). Conversely, when excluding HCV + patients in both groups, graft survival in HIV + and HIV - patients was similar. The outcome was good, particularly in non-coinfected patients. Coinfected patients constitute an especially high-risk group for kidney transplantation.
    Nephrology Dialysis Transplantation 04/2011; 26(4):1401-7. · 3.37 Impact Factor
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    American Journal of Transplantation 03/2011; 11(3):635-6. · 6.19 Impact Factor
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    ABSTRACT: A prospective study was performed in kidney transplant patients at risk of developing cytomegalovirus (CMV) infection (CMV D+/R-). They were treated with valganciclovir (VGC) for 3 months as prophylactic therapy. The aim was to determine the safety and efficacy of prophylactic therapy with VGC. Antigenemia and/or polymerase chain reaction CMV was routinely performed every 2 weeks up to month 3, monthly to month 6, and every other month until the end of the first year posttranplantation, as well as when clinically indicated. From July 2007 to April 2010, 366 renal transplantations were performed at our center, including 34 (9%) high-risk patients for CMV infection. The median age was 47 years; 19 were males and 15 females. Twelve (35%) patients developed CMV infections: 10 (34%) gastrointestinal disease and 3 viral syndromes. The timing of the clinical manifestations was 16% (3/12) between months 1 and 3, 75% (8/12) between months 4 and 6, and 8% (1/12) in month 9 posttransplantation. Treatment with intravenous ganciclovir followed by oral VGC was successful in all patients. No opportunistic infections or allograft rejection were observed; only 1 patient developed thrombocytopenia as an adverse event to VGC.
    Transplantation Proceedings 10/2010; 42(8):2947-9. · 0.95 Impact Factor
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    ABSTRACT: Treatment with oral risedronate to prevent bone mineral density (BMD) loss in renal transplant recipients has been shown to be effective. There is no agreement on the optimum moment of introduction or how long it should be continued. The aim was to evaluate the effectiveness of risedronate at doses of 35 mg/week in renal transplant recipients who underwent treatment immediately after transplant. A randomized clinical trial was performed on 101 renal transplant patients. The study group (52 patients) received 35 mg risedronate weekly, vitamin D, and calcium, whereas the control group (49 patients) received only vitamin D and calcium. At baseline, 3, 6, and 12 months, basic biochemistry and mineral bone metabolic parameters were determined. Vertebra and hip fracture assessment was performed by means of x-ray and DEXA; an intention-to-treat analysis was performed. Patients in control group showed a significant worsening of BMD (P<0.05) 12 months into the study. At all follow-up points, lumbar BMD of the study group was significantly greater (P<0.05), whereas femoral BMD of those treated with risedronate was only significant at 6-month follow-up (P<0.05). There was a trend of more vascular calcifications and fractures in the control group, but this was not statistically significant. Weekly oral administration of risedronate immediately after renal transplantation contributes to an improved BMD, particularly in the femoral neck at 6-month follow-up, without major side effects. Long-term follow-up is needed to establish whether oral risedronate has an influence on vascular calcifications and bone fractures.
    Transplantation 06/2010; 89(12):1476-81. · 3.78 Impact Factor
  • Transplantation 01/2010; 90. · 3.78 Impact Factor
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    ABSTRACT: EVALUATION OF THE RENAL FUNCTION: For the follow-up of the graft renal function it must be measured the glomerular filtration rate by means of formulae that use the serum creatinine. The most used equation is the brief formula MDRD. - All patients transplanted must be included in the group of Renal Chronic Disease though the glomerular filtration rate is normal and there is no evidence of renal damage. - The measures of intervention proposed in the classification of the Renal Chronic Disease for its progressive establishment in the stage 1 to 3, must be applied to all the transplanted THE BEGINNING OF DIALYSIS: In spite of receiving attention of Nephrologists along the whole evolution, the patients with chronic dysfunction of the graft that need treatment with dialysis start later and with more uremic complications that the patients who start dialysis for the first time. - To change this trend, it is necessary to consider the treatment with dialysis when the glomerular filtration rate is lower than 15 ml/min/1,73 m2. If there appears any complication related to the uremia that cannot be handled by conservative treatment, the beginning of the dialysis is necessary. THE BEGINNING OF THE DIALYSIS OF PROGRAMMED FORM: The beginning of the dialysis of not programmed form in transplanted patients is difficult to justify if we take into account that such patients, have received nephrological attention along all their evolution. - To get a new vascular access in these patients can be difficult depending on the previous trombosis of arteriovenous fistulas. Therefore, it must be realized a prompt evaluation for de department of vascular surgery to guarantee a suitable vascular access. - As general norm, one must follow the same criterion advised for the not transplanted patient: the vascular access must be considered when the glomerular filtration rate is lower than 20 m/min/1,73 m2. - The patient who is going to be treated by dialysis peritoneal precise a very narrow follow-up to be able to programme the placement of the catheter peritoneal with a minimum of 15 days before beginning the training.
    Nefrologia: publicacion oficial de la Sociedad Espanola Nefrologia 01/2009; 29 Suppl 1:38-43. · 1.27 Impact Factor
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    ABSTRACT: Most immunosuppressive protocols in de novo renal transplantation include tacrolimus in combination with mycophenolate mofetil/mycophenolic acid (MMF/MPA) and prednisone. A variable percentage of patients show intolerance to MMF/MPA needing a reduction, interruption, or suspension of the drug, thereby exposing the patient to a greater risk of a rejection episode. The association of everolimus and tacrolimus may prove to be an alternative option in such cases. The aim of this study was to present our clinical experience, evaluating the incidence of graft rejection. We performed a descriptive study of 19 kidney transplant patients from 2001-2008 who were treated with tacrolimus, MMF/MPA, and prednisone and displayed gastrointestinal or hematological adverse events to MMF/MPA, which were addressed with everolimus. We analyzed parameters up to 2 years after the change. The doses and levels of everolimus were increased progressively. At the same time, we decreased the doses and levels of tacrolimus. Renal function remained stable during the period and there was no case of a rejection episode during the 2 years. Only 5 patients (26%) showed side effects which were attributable to everolimus; 36% of patients required starting and/or increasing the erythropoietin dose, 15% required iron supplements, 15% required diuretics, and 31% began or increased treatment with statins. Our experience suggested that a combination of tacrolimus and everolimus may be a safe, effective alternative for kidney transplant patients who show intolerance to MMF/MPA.
    Transplantation Proceedings 01/2009; 41(6):2095-8. · 0.95 Impact Factor
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    ABSTRACT: The choice of the most of dialysis modality after renal graft loss is an unanswered question. Most patients start hemodialysis (HD) in this situation, because of several reasons: 1. In most dialysis programs HD predominates clearly over Peritoneal Dialysis (PD). 2. The star of dialysis in emergency situations makes the physician use HD 3. The fear of infections in case of maintenance of immunosupression to avoid immune response and to keep residual renal function in case of PD. A lot of patients could undergo PD in order to maintain the previous style of life, as an alternative in case of absence of vascular access and to avoid vascular accesses in children. Mortality seems to be greater in patients with graft loss than in those who start dialysis for the first time, although the comparison between both groups is methodologically difficult. However, there is no difference in mortality between patients who start HD and those who start PD. Studies comparing the rate of peritonitis in PD patients in both groups find controversial results. The analysis of the few, retrospective and biased studies which look for differences in patient survival in HD and DP suggests that prognosis of both groups is similar. The choice of dialysis modality must be similar to those patients which begin dialysis for the first time.
    Nefrologia: publicacion oficial de la Sociedad Espanola Nefrologia 01/2009; 29 Suppl 1:44-8. · 1.27 Impact Factor
  • Transplantation 01/2008; 86:545-546. · 3.78 Impact Factor
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    ABSTRACT: Everolimus (Eve) has shown good efficacy and safety profiles in clinical trials in combination with low doses of cyclosporine but there is limited experience in other modes, especially with calcineurin inhibitor elimination. We developed a retrospective study to analyze its clinical use after approval in Europe in 2005. Herein we have presented the results of a series of 272 patients followed for the first 6 months after Eve introduction. In 93.8% of cases Eve was introduced after the first month posttransplantation (conversion use), and 6 months after introduction, the CNI had been eliminated in 75% of cases. The main indication for Eve introduction was the diagnosis of a malignant neoplasm (42%), whereas the combined indication of prevention and/or treatment of toxicity, especially nephrotoxicity, accounted for 46.3% of cases. Initial doses were low (1.37 mg/d), but were progressively increased up to 2 mg/d at 6 months. Renal function remained unchanged during the follow-up period, whereas proteinuria moderately increased. Only 5 cases (2%) of acute rejection episodes were observed with excellent patient and graft survivals at 6 months after conversion. Further analysis of this extensive series of patients with a longer follow-up is needed.
    Transplantation Proceedings 10/2007; 39(7):2157-9. · 0.95 Impact Factor
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    ABSTRACT: To evaluate the efficacy and safety of conversion from cyclosporine to tacrolimus, we analyzed 55 kidney transplant patients who were converted due to cosmetic reasons in 42 patients, acute rejection in 2 patients, and other causes in 11 patients. At the doses and levels used, the development of diabetes mellitus was minimized. Disappearance of cosmetic side-effects and improvement of cardiovascular risk factors, together with conservation of renal function, encourage us to use tacrolimus as an efficacious and safe immunosuppressive therapy.
    Transplantation Proceedings 09/2003; 35(5):1704-5. · 0.95 Impact Factor
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    ABSTRACT: Although hyperuricaemia and gout are frequently found in renal transplant recipients, little has been published on the efficacy of urate-lowering therapy (ULT) in this patient population. We therefore examine the effects of allopurinol and benziodarone therapy in a cohort of renal transplant patients. We reviewed files from a cohort of 1328 patients that received renal transplantation. The selection criteria included: functioning allograft, hyperuricaemia for >12 months or gout, ULT lasting at least 1 year and at least two control measurements after the onset of ULT. Patients on azathioprine were treated with benziodarone to avoid azathioprine-allopurinol interactions. Two-hundred and seventy-nine patients fulfilled the criteria for review. They were treated with 289 courses of ULT: 100 with allopurinol (mean dose: 376 mg/day/dl/min of creatinine clearance) and 189 with benziodarone (mean dose: 73 mg/day). The mean follow-up was 38 months. Both drugs were effective for the control of hyperuricaemia, but benziodarone caused greater reductions in serum uric acid levels, especially when used at mean doses of >75 mg/day. Severe side effects were uncommon, in both the allopurinol and benziodarone groups. Both allopurinol and benziodarone were effective for the control of hyperuricaemia in renal transplantation. Benziodarone at doses >75 mg/day was more effective than allopurinol in reducing serum uric acid levels and also reduced the risk of azathioprine-allopurinol interactions.
    Nephrology Dialysis Transplantation 03/2003; 18(3):603-6. · 3.37 Impact Factor
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    ABSTRACT: Two cases of infections due to Scedosporium apiospermum in renal transplant recipients, one localized in the central nervous system, the other in the skin, are presented, and a literature review of 21 cases of central nervous system and cutaneous infections due to Pseudallescheria boydii/Sc. apiospermum is given.
    Mycoses 12/2002; 45(9-10):418-27. · 1.28 Impact Factor
  • Enfermedades Infecciosas y Microbiología Clínica 04/2002; 20(3):129-30. · 1.48 Impact Factor
  • Transplantation Proceedings 03/2002; 34(1):87-8. · 0.95 Impact Factor