Presence of T-275A and C-2152T Polymorphisms of the Promoter Region of Uridine Diphosphate-Glucuronosyltransferase 1A9 Increases Mortality From Digestive Tumors: Results After 10 Years of Follow-up in a Renal Transplant Population.

BACKGROUND: The aim of this study was to determine the distribution of uridine diphosphate-glucuronosyltransferase 1A9 (UGT1A9) promoter region T-275A and C-2152T single-nucleotide polymorphisms (SNPs) in stable transplant patients and to investigate the impact of these SNPs on the evolution of this population after 10 years of follow-up. METHODS: White renal transplant recipients (n = 873) were studied. The median time of follow-up was 91.8 months (P25-75 46-146). Amplification with specific "primers" to delimit the study area was performed for each polymorphism. Amplification was performed with the use of real-time polymerase chain reaction. RESULTS: T-275A promoter mutation was detected in 13% of patients and C-2152T in 12% of patients. Survival analysis was performed on 873 renal transplants, carried out between 2004 and 2013. We found a higher frequency of death from cancer among polymorphism carriers (P = .001). CONCLUSIONS: It appears that carriers of T-275A and C-2152T SNPs of the UGT1A9 gene promoter region show a greater incidence of death from cancer, with a significantly higher cumulative incidence of death from gastrointestinal tumors.

Surgical Complications in En Bloc Renal Transplantation.

En bloc pediatric transplantation (EBPT) began with the aim of increasing the donor pool due to the existing high demand for donors. At its inception, it was considered a type of suboptimal transplantation due to its association with a high incidence of vascular, urologic, and immunologic complications. The main objective of this study was to update information on EBPT with the largest case series that exists on a worldwide scale. In a retrospective study, the results obtained from brain-dead donors (BDDs; n = 770) were compared to those of EBPT (n = 100) from January 1990 to December 2012. The median of follow-up was 12.8 years (interquartile range 8.1 to 17.2). The variables collected for analysis were demographic factors (age and sex of recipients, age and weight of donors), renal function, graft survival, recipient survival, surgical complications (thrombosis, lymphocele, urologic complications, and renal artery stenosis and need for revascularization with angioplasty and/or stents). Subsequently in a second analysis, we studied the association between graft survival, thrombosis, angioplasty, stents, and appearance of lymphoceles with the different factors that were considered to be related in accordance with published literature and our own experience. Graft loss due to surgical complications was more frequent in EBPT than in BDD (15% vs 2.2 % in BDD; P < .001), and interstitial fibrosis and tubular atrophy were more frequent in BDD (13% vs 2%; P < .001). EBPT offers a good survival rate after overcoming the possible surgical complications that may arise.

Risk Factors of Recurrence of Diabetic Nephropathy in Renal Transplants.

BACKGROUND: Renal transplantation has been established as the treatment of choice for end-stage renal disease (ESRD) due to diabetic nephropathy. This study aimed to investigate the risk factors for recurrence of diabetic nephropathy (RDN) in renal allografts. METHODS: We studied 1,011 renal transplant patients from 1986 to 2003, of which 95 had ESRD due to diabetic nephropathy. We retrospectively analyzed the clinical characteristics and outcomes of RDN after renal transplantation. RESULTS: Of the 95 recipients with ESRD due to diabetic nephropathy, 41 developed RDN and 11 of those 41 underwent graft biopsy. The mean durations from transplantation to RDN and to renal replacement therapy was 81.58 months (range, 54-120 mo), and 109.66 months (range, 27-188.4 mo), respectively. At 5 years, treatment on statins and renin-angiotensin-aldosterone system (RAAS) blockers were associated with a higher survival free from RND (82.2% vs 63.2% [P = .070] and 100% vs 80% vs 0.6% [P = .013], respectively). Compared with cyclosporine, tacrolimus was associated with a higher risk for RND (odds ratio [OR], 4.27; 95% confidence interval [CI], 1.75-5.13; P = .047). High doses of prednisone (>0.06 mg/kg) were also associated with a higher risk of RDN (OR, 3.03; 95% CI, 1.19-8.30; P = .029). The combination of calcineurin inhibitor and mammalian target of rapamycin inhibitor (mTORi) demonstrated the highest risk of RDN (OR, 14.08; 95% CI, 3.72-53.29; P < .01). CONCLUSIONS: Treatment with tacrolimus and mTORi is the most diabetogenic immunosuppressive regimen. Treatment with tacrolimus entails a greater risk of RDN than with cyclosporine. The administration of statins or RAAS blockers could delay the progression of RDN.

Whooping cough in a renal transplant recipient.

Whooping cough is a respiratory infection with a severity that varies with age, immune status, and probably with other factors such as the degree of exposure and the virulence of the organism. The most frequent microorganism responsible for whooping cough is Bordetella pertussis. We present the case of a 62-year-old renal transplant recipient presenting with typical and severe manifestations of whooping cough caused by B. pertussis.

Role of fibroblast growth factor 23 (FGF23) in the metabolism of phosphorus and calcium immediately after kidney transplantation.

INTRODUCTION: Persistence of inappropriately high serum levels of fibroblast growth factor-23 (FGF23), a recently discovered phosphaturic hormone, has been reported to play an important role in the pathogenesis of posttransplant hypophosphatemia. The aim of the present study was to evaluate FGF23 in the early posttransplant period and study the complex associations between FGF23, parathyroid hormone (PTH), 1,25(OH)(2) vitamin D, and phosphate in transplant patients. MATERIALS AND METHODS: We performed a cross-sectional observational study of 42 adult kidney recipients in the early posttransplant period (<6 months). Fasting serum samples and 24-hour urine samples were collected during a routine follow-up outpatient visit. Serum creatinine, calcium, phosphate, magnesium and urinary creatinine, calcium, magnesium, and phosphate were measured using standard assays. We also studied concentrations of 25 hydroxyvitamin D, 1,25(OH)(2) vitamin D, intact PTH, and circulating FGF23. RESULTS: Median values for the different parameters studied were as follows: 9.9 ± 0.6 mg/dL, phosphatemia 3.3 ± 0.7 mg/dL, estimated glomerular filtration rate (eGFR; 41.1 ± 14.0 mL/min, phosphate reabsorption rate 68.4% ± 10.7%, PTH 94.5 ng/L (53.8-199.5), calcitriol 33.0 pg/mL (24.0-44.1), calcidiol 27.3 ng/mL (17.0-38.0), FGF23 139 pg/mL (88-221), and calciuria 62.5 mg/d (40.3-101.3). The variables significantly associated with serum FGF23 levels were phosphate reabsorption rate (r = .493; P = .001), calcitriol (r = .399; P = .009), eGFR (r = .557; P < .001), PTH (0.349; P = .024). CONCLUSIONS: Elevated serum levels of FGF23 could explain the deficiency of calcitriol and elevated renal phosphorus wasting in the early posttransplant period. All treatments that can lead to increased serum phosphate levels (eg, oral medication or calcitriol) should be carefully evaluated, since increased phosphatemia could further stimulate secretion of FGF23 and prolong high phosphorus loss.

Mammalian target of rapamycin signal inhibitors could play a role in the treatment of BK polyomavirus nephritis in renal allograft recipients.

UNLABELLED: BK virus (BKV) nephropathy is a common viral infection in renal transplant patients, with a prevalence of 1-9% at approximately 12 months after surgery. While it is widely agreed that reduction of immunosuppression should be the first intervention after diagnosis of BKV infection, there is no consensus on whether calcineurin inhibitors or antiproliferative drugs should be reduced first. Furthermore, target levels of immunosuppressive drugs are poorly defined, as are criteria for replacing one immunosuppressive agent with another. RESULTS: We report our series of 15 renal transplant patients who underwent surgery between September 2004 and March 2010 and who developed BKV infection. The first 8 patients were treated with reduction of immunosuppression; 7 of these patients received cidofovir and 6 received intravenous immunoglobulin. The remaining 7 renal transplant recipients received mammalian target of rapamycin inhibitors (imTOR). In this group, we observed faster and more efficacious BKV clearance in plasma and urine and a steady improvement in allograft function, with no episodes of acute allograft rejection during follow-up. The polymerase chain reaction assay for BKV in urine became positive in 2 patients in whom imTOR were stopped due to severe side effects. CONCLUSIONS: The use of imTOR should be considered a first step in the treatment of renal transplant recipients with BKV infection. In our experience, this change in treatment was safe and resulted in viral clearance.

De novo anti-HLA antibodies in renal allograft recipients: a cross-section study.

BACKGROUND: The occurrence of anti-HLA antibodies plays a well established role in solid organ rejection. The development of x-MAP multiple bead technology (Luminex) has enabled more accurate detection and definition of these alloantibodies. METHODS: In 267 kidney transplant patients with stable allograft function for ≥3 years, we analyzed the presence of anti-HLA antibodies by Luminex technology. These patients had no alloantibodies before transplantation, and the immunosuppression treatment was: tacrolimus, cyclosporine, mycophenolate mofetil, prednisone, everolimus, and/or sirolimus. RESULTS: Fifteen of the 267 patients showed anti-HLA class I antibodies and 12 showed anti-HLA class II antibodies, Seven patients had donor-specific antibodies (DSA): 1 anti-HLA class I, 5 anti-HLA class II, and 1 with both classes. No differences were found between DSA and the use or not of any specific therapy. However, in the retrospective review, we found a higher incidence of acute rejection episodes in the immediate posttransplant period among patients who developed class II DSA than those without DSA. CONCLUSIONS: The prevalence of patients with normal renal function who develop DSA beyond 3 years after transplantation was relatively low. Steroid or withdrawal replacement of calcineurin inhibitors with inhibitors of mammalian target of rapamycin seem to not be risk factors to increase the development of DSA. The finding that patients who developed DSA showed a higher rate of previous acute rejection episodes suggested that they should be monitored more frequently for HLA antibodies.

Candiduria in renal transplant recipients: incidence, clinical repercussion, and treatment indication.

INTRODUCTION: The incidence of candiduria in renal transplant recipients is unknown. In clinical practice, the indications for antifungal therapy are not well established. Furthermore, there is the problem of the choice of the antifungal drug since some of them may select resistant Candida species, or interact with immunosuppressive agents or only be used intravenously. AIM: We sought to study the incidence, clinical repercussions and effectiveness of antifungal treatment to prevent recurrence of candiduria. MATERIALS AND METHODS: We examined all episodes of Candida-positive urine cultures (>50,000 cfu/mL) in 996 recipients over 2 years. We considered the Candida species, administered treatment, presence of fever, requirement for hospital admission versus outpatient case, occurrence of simultaneous bacterial urinary tract infection (UTI), antibiotic use during the week before candiduria, and presence of an indwelling urinary catheter. RESULTS: Among 996 subjects, 34 displayed 83 episodes of candiduria, yielding an accumulated incidence of 3.4% after 2 years. The frequency was higher among women (6.3% vs 1.7%, P<.001). Of the 45 outpatient episodes (54.2%), 17 were treated and one required hospitalization (5.9%). Of the 28 nontreated outpatients, two were hospitalized (7.1%, P=.68 vs treated patients). All cases of hospital admission presented simultaneous bacterial UTI, none developed candidemia, and two patients did not receive any antifungal therapy. With respect to the first episodes of each patient (n=34), 5/11 treated (45.5%) and 4/23 untreated (17.4%) patients developed recurrences (P=.095). Selection of more resistant Candida species was not observed. Fifty cases (60%) were associated with antibiotic therapy and 34 (41%) the presence of a urinary catheter. CONCLUSIONS: It does not seem necessary to treat candiduria in this setting. Antifungal therapy was not associated with either a reduction in recurrence or the appearance of more resistant species in this study. We observed no important clinical repercussions.

Changes in magnesium and potassium homeostasis after conversion from a calcineurin inhibitor regimen to an mTOR inhibitor-based regimen.

BACKGROUND: Transplant recipients treated with calcineurin inhibitors (CNIs) frequently show hyperkalemia, metabolic acidosis, and hypomagnesemia which could be deleterious for some patients. Conversion to inhibitors of mammalian target of rapamycin (mTOR) could improve these electrolytic disturbances. OBJECTIVE: To evaluate the potassium and magnesium changes due to converting patients from CNIs to mTOR inhibitors. METHODS: Retrospective review of 138 renal transplant patients who were converted from CNIs to mTOR inhibitors over a 6-month observation period. The following parameters were determined: potassium, sodium, chloride, magnesium, urea, glucose, and creatinine in blood and urine. We also analyzed plasma bicarbonate and calculated plasma and urine anion gap and plasma osmolarity. RESULTS: One month after conversion, a decrease was observed in serum creatinine (1.75±0.68 vs 1.61±0.61 mg/dL; P=.01), plasma potassium (4.60±0.52 vs 4.39±0.53 mEq/L; P<.001), calculated plasma osmolarity (308.7±8.5 vs 307.4±8.4 mOsm/L; P<.036), fractional excretion of sodium (1.55±0.69 vs 1.29±0.65%; P<.003), and fractional excretion of magnesium (7.15±4.08 vs 15.84±3.64%; P<.001), with an increase in serum magnesium (1.77±0.24 vs 1.95±0.29 mg/dL; P<.001). At 3 and 6 months, these differences remained unchanged. The transtubular potassium gradient did not change. CONCLUSIONS: We observed a decrease in serum magnesium due to renal magnesium wasting before switching from CNIs to mTOR inhibitors. After conversion, an increase in serum magnesium was observed together with a drop in the fractional excretion of this cation. A decrease in plasma potassium levels, plasma osmolarity, and fractional excretion of sodium consistent with minor aldosterone resistance was also detected after changing the immunosuppressive treatment.

Comparative analysis of adverse events requiring suspension of mTOR inhibitors: everolimus versus sirolimus.

BACKGROUND: Inhibitors of mammalian target of rapamycin (mTORi) have been suggested as an alternative to calcineurin inhibitors (CNIs) to treat stable renal transplant recipients. However, their use has been significantly limited owing to a high incidence of side effects. OBJECTIVE: To compare the rate of dropout (mTORi elimination and CNI reintroduction) caused by side effects among renal transplant patients converted to everolimus (EVL) or sirolimus (SRL). METHODS: Between October 1999 and February 2010, 409 subjects were converted to an mTORi at least 3 months after transplantation, including 220 (53.8%) to EVL and 189 (46.2%) to SRL. Most patients were under CNI therapy. Patients were followed for a median of 35 months (interquartile range [IQR], 18-50 months). RESULTS: mTORi treatment was prematurely eliminated due to adverse events in 112 patients. The median time between the initiation of mTORi and discontinuation was 5.7 months (IQR, 1.9-15.7 months; range, 0.2-48 months): 5.5 (IQR, 1.6-16.3) in the EVL group and 7.4 (IQR, 2.6-15.6) in the SRL group. In the EVL group, the drug was stopped in 69 patients (31.4%), and in the SRL group in 43 patients (22.8%; P=.051). The most important causes of discontinuation were severe infections (2.3% in EVL group and 4.8% in SRL group; P=.17), pneumonitis (6.8 % in EVL group and 4.8 in SRL group; P=.38), acute rejection episode (4.1% in EVL group and 1.6% in SRL group; P=.13), proteinuria (4.1% in EVL group and 1.6% in SRL group; P=.13), renal function deterioration (2.3% in EVL group and 2.1% in SRL group; P=.91), and severe dermal eruption (2.3% in EVL group and 0.5% in SRL group; P=.14). CONCLUSIONS: Although the overall incidence discontinuations due to side effects was higher in the EVL group, there was no greater frequency of severe side effects, such as pneumonitis, proteinuria, acute rejection episodes, renal function deterioration, or dermal eruptions.

Inadequate mycophenolic acid exposure and acute rejection in kidney transplantation.

INTRODUCTION: The clinical utility of predose levels of mycophenolic acid (MPA) monitoring among patients treated with mycophenolate mofetil (MMF) has been questioned. The aim of this study was to evaluate the impact of adequate MPA levels in the incidence of acute rejection episodes among a cohort of kidney transplant recipients. MATERIAL AND METHODS: In this retrospective study of 314 consecutive cases treated with tacrolimus, MMF, and steroids, evaluated 12-hour trough MPA samples during the first week as well as at 1, 3, 6, and 12 months as median values. RESULTS: During the first week, the median values of MPA were 1.6 microg/mL (p25-75 0.7-2.7 microg/mL) on mean doses of 1.84 +/- 0.38 g/d. The incidence of acute rejection was 28%. The mean MPA levels during the first week were significantly lower among patients who developed rejection than in nonrejectors (1.5 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P < .001). There were no significant differences in trough tacrolimus levels between rejectors and nonrejectors (11.2 +/- 0.4 vs 11.6 +/- 1.2 microg/mL; P < .78). Logistic regression analysis showed that one of the predictive factors of acute rejection was a 12-hour trough MPA <1.6 microg/mL (relative risk [RR] 2.6; CI [confidence interval] 95% 1.6-4.3; P < .001). CONCLUSIONS: Adequate MPA exposure is important to prevent acute rejection. Taking into account that the routine measurement of the area under the curve of MPA is impractical, at least the follow-up of trough MPA levels may help in the management of renal transplant recipients.

Graft outcome and mycophenolic acid trough level monitoring in kidney transplantation.

BACKGROUND: Large inter- and intrapatient variabilities have been observed in the pharmacokinetics of mycophenolic acid (MPA). As a consequence, the efficacy and safety of mycophenolate mofetil (MMF) may be optimized with individualized doses based on therapeutic drug monitoring. MATERIALS AND METHODS: In this retrospective study we analyzed; 7536 12-hour trough MPA samples obtained during the first year posttransplantation among 314 kidney recipients treated with tacrolimus, MMF, and corticosteroids. RESULTS: Despite taking similar MMF doses, patients with delayed graft function (DGF) showed lower 12-hour trough MPA levels than patients without DGF 1.4 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P = .001). There was a significant correlation between 12-hour trough MPA levels and creatinine clearance (r = .32; P < .001). Logistic regression analysis showed that creatinine clearance was a predictive factor of adequate 12-hour trough MPA levels (>1.6 microg/mL) at 7 days posttransplantation. Twelve-hour trough MPA levels at 7 days posttransplantation were lower among patients who developed an acute rejecton episode (1.5 +/- 0.1 vs 2.1 +/- 0.1 microg/mL; P < .001), whereas those with gastrointestinal side effects showed high levels (4.1 +/- 0.5 microg/mL). CONCLUSIONS: In patients with delayed or poor graft function, MMF doses greater than 2 g/d may be necessary to achieve adequate MPA levels. Therapeutic drug monitoring of MPA may be useful to prevent acute rejection episodes or toxicity.

Sirolimus and everolimus induced pneumonitis in adult renal allograft recipients: experience in a center.

Mammalian target of rapamycin (mTOR) inhibitors induce pneumonitis, an unusual but potentially fatal side effect of this drug group. We retrospectively collected the cases of pneumonitis induced by sirolimus or everolimus among 1471 adult cadaveric renal transplant recipients who were grafted at our institution from 1980-2008. Due to chronic transplant dysfunction or tumor, 205 patients were switched from calcineurin inhibitors to sirolimus (n = 88) or to everolimus (n = 117). Six patients (2.9%) developed pneumonitis: 1 was associated with sirolimus and 5 with everolimus (5 males and 1 female; median age, 60 years [range, 47-73 years]). Median times from conversion to pneumonitis onset were 34 days in 4 patients (range, 24-46 days) and 491 days in 2 subjects (range, 454-528 days). The mean drug trough level at presentation was 8.2 microg/L (range, 5.5-13.8 microg/L). The most common symptoms were dry cough (n = 6), fever (n = 5), and dyspnea (n = 4). Imaging tests revealed lower lobe involvement in all patients. Bronchoalveolar lavage performed in 4 patients showed lymphocytic alveolitis. All patients completely recovered after drug withdrawal. Five patients received steroids, 5 were switched to a calcineurin inhibitor, and 1 was switched to the other mTOR inhibitor. In conclusion, mTOR inhibitor-associated pneumonitis is a rare disease. Sirolimus did not cause more cases of pneumonitis than everolimus. Pneumonitis development was not dependent upon the drug blood level. Lower lobe involvement and lymphocytic alveolitis were usually present. Discontinuation of the mTOR inhibitor with steroid prescription resulted in adequate outcomes. A change to the other mTOR inhibitor should be contemplated if patient circumstances require this type of immunosuppression.

The prevalence of uridine diphosphate-glucuronosyltransferase 1A9 (UGT1A9) gene promoter region single-nucleotide polymorphisms T-275A and C-2152T and its influence on mycophenolic acid pharmacokinetics in stable renal transplant patients.

UNLABELLED: The aim of this study was to evaluate the distribution of UGT1A9 promoter region T-275A and C-2152T single nucleotide polymorphisms (SNPs) in stable transplant patients and to investigate the impact of these SNPs on mycophenolic acid (MPA) pharmacokinetics. METHODS: In total, 133 Caucasian renal transplant recipients were studied. Also a complete 12-hour pharmacokinetic profile was recorded for 15 transplant patients who had the polymorphism and for 15 controls who were randomly chosen since they received the same type and dosage of mycophenolate, same posttransplant time and similar renal function. RESULTS: The T-275A promoter mutation was detected in 12.03% of patients and the C-2152T in 9.77%. All patients with the mutation C-2152T had associated the mutation T-275A. Patients who carried either the T-275A or the C-2152T polymorphism (or both) experienced more admissions owing to gastrointestinal side effects (P < .05). The pharmacokinetics studies showed that carriers of T-275A and/or C-2152T displayed a smaller area under-concentration time curve (AUC): 57.8 +/- 4.3 vs 78.9 +/- 10.8 mg/L*h (P < .03). CONCLUSION: It seemed that carriers of T-275A and C-2152T SNPs of the UGT1A9 gene promoter region in the late posttransplant recipient group, showed a greater incidence of gastrointestinal side effects and a lower MPA exposure.

Inmunosupresores / No disponible

En las últimas dos décadas, han aparecido nuevos inmuno-supresores que han conseguido una disminución importante en la tasa de rechazo agudo y en la supervivencia acorto plazo del injerto. Esta mejoría, sin embargo, no ha tenido el impacto esperable en la supervivencia a largo plazo del trasplante. Paradójicamente, los fármacos más utilizados y eficaces para evitar el rechazo agudo, esto es los inhibidores de calcineurina, contribuyen a la pérdida tardía del injerto y a la muerte del paciente, puesto que son drogas nefrotóxicas y que además producen efectos adversos en la tensión arterial, metabolismo lipídico y homeostasis de la glucosa. Por ello ha sido necesario el desarrollo de nuevas moléculas exentas de estos efectos colaterales, que permitan el uso de regímenes libres o con dosis reducidas de inhibidores de calcineurina sin llevar ala aparición de otros efectos deletéreos para la supervivencia del paciente y del injerto. Así, el gran desarrollo en el campo de la inmunología ha llevado al descubrimiento de nuevas vías importantes en la respuesta aloinmune, desarrollándose posteriormente moléculas que actúan selectivamente frente a diferentes puntos de la activación de la cascada inmunológica. En este artículo vamos a revisar los datos clínicos más relevantes publicados sobre inmunosupresión y presentados en los diferentes congresos a lo largo del año 2007, seleccionando aquellos que nos han parecido más relevantes y que en el futuro pueden tener impacto sobre el tratamiento de nuestros pacientes (AU)

In the past two decades, new immunosuppressive drugs have emerged that have achieved a significantly reduction in acute rejection and short-term graft survival. This improvement, however, has not had the expected impact on long-term survival of the transplant. Paradoxically, the most used and effective drugs to prevent acute rejection are calcineurin inhibitors, but they contribute to delayed graft loss and patient death because they are nephrotoxic and also cause other adverse effect son blood pressure, lipid metabolism and glucose homeostasis. It was therefore necessary to develop new molecules free from these side effects that allow the use of low-dose or calcineurininhibitor-free regimens without causing other adverse effect son patient and graft survival. Thus, the great development in the field of immunology has led to the discovery of important new pathways in the alloimmune response and subsequent development of molecules that act selectively against different points in the activation of the immune cascade. In this article we will review the most relevant clinical data published on immunosuppressant and presented at different congresses over the year 2007, selecting those that we considered most relevant and that may have impact on the treatment of our patients in the future (AU)

[Immunosuppressors]. / Inmunosupresores.

In the past two decades, new immunosuppressive drugs have emerged that have achieved a significantly reduction in acute rejection and short-term graft survival. This improvement, however, has not had the expected impact on long-term survival of the transplant. Paradoxically, the most used and effective drugs to prevent acute rejection are calcineurin inhibitors, but they contribute to delayed graft loss and patient death because they are nephrotoxic and also cause other adverse effects on blood pressure, lipid metabolism and glucose homeostasis. It was therefore necessary to develop new molecules free from these side effects that allow the use of low-dose or calcineurin inhibitor-free regimens without causing other adverse effects on patient and graft survival. Thus, the great development in the field of immunology has led to the discovery of important new pathways in the alloimmune response and subsequent development of molecules that act selectively against different points in the activation of the immune cascade. In this article we will review the most relevant clinical data published on immunosuppression and presented at different congresses over the year 2007, selecting those that we considered most relevant and that may have impact on the treatment of our patients in the future.

Renal transplant patients with gastrointestinal intolerability to mycophenolate mofetil: conversion to enteric-coated mycophenolate sodium.

The introduction of mycophenolate mofetil (MMF) was an important advance in immunosuppressive therapy, although its use is limited by adverse gastrointestinal events. Enteric-coated mycophenolate sodium (EC-MPS; myfortic) has been developed to avoid these side effects. Recent clinical trials have demonstrated that EC-MPS is a safe drug in both de novo and maintenance renal transplant patients. In this prospective study, therapeutically equivalent doses of EC-MPS were administered to 39 stable kidney transplant patients receiving MMF. After 3 months of treatment with EC-MPS the incidence of adverse gastrointestinal events was lower (15.8% of the patients). There were higher levels of mycophenolic acid after conversion to EC-MPS, probably due to better absorption. These factors allowed decreased doses and levels of calcineurin inhibitors without increasing the risk of graft rejection. At 3 months postconversion, serum creatinine improved from the mean baseline value of 1.83 +/- 0.12 mg/dL to 1.70 +/- 0.10 mg/dL. In conclusion, EC-MPS was well tolerated in maintenance renal transplant patients with adverse gastrointestinal events secondary to MMF.

Varicella infection in adult renal allograft recipients: experience at one center.

Disseminated varicella-zoster virus (VZV) infection in adult renal allograft recipients is a rare but potentially fatal illness. We retrospectively collected the cases of VZV infection that occurred in 812 adult renal transplant recipients, performed between 1995 and 2004 at our institution. Eight patients developed varicella (1%), seven men and one woman. The overall median age was 38 years (range = 31 to 64). The median time from transplantation to infection was 32 months (range = 2 to 92). Four cases were primary infections and four disseminated VZV reactivations. Immunosuppression consisted of prednisone (PDN) + cyclosporine (CSA) + mycophenolate (MF; n = 4); PDN + CSA + azathioprine (n = 1); PDN + tacrolimus (FK) + MF (n = 1); FK + MF (n = 1); PDN + rapamycin + MF (n = 1). Seven patients (87%) required hospital admission for a median duration of 11 days (range = 3 to 21). Four patients were previously diagnosed with chronic hepatitis virus infection: two type B (HBV) and two type C (HCV). The last cohort required longer admission than the negative patients (11.5 +/- 3 vs 7.5 +/- 9 days; P = .1). The only clinical manifestation in four patients was general malaise, fever, and a disseminated vesicular rash; the other four patients also showed visceral involvement: two pneumonitis, one hepatitis, and thrombotic microangiopathy, and one developed multiorgan failure and died due to a delayed diagnosis in a patient positive for HBVs. The diagnosis was established according to the symptoms, IgG-IgM seroconversion and VZV polymerase chain reaction quantification in vesicle contents. Treatment consisted of reduced immunosuppression, antiviral drugs (acyclovir or gancyclovir), and in six patients, a varicella-zoster immunoglobulin dose. We concluded that varicella infection in adult renal allograft recipients is unusual but highly morbid. A vaccination program in seronegative pretransplant candidates should be attempted. Early diagnosis and treatment may improve the prognosis. Although further studies are required, chronic HBV or HCV infection seemed to be a risk factor for the disease.