Tissue talks: immunophenotype of cells infiltrating the graft explains histological findings and the benefits of belatacept at 10 years.

Previously, we found a substantial number of regulatory T cells (Tregs ) and fewer senescent and T helper type 17 (Th17) and a decrease in interstitial fibrosis (IF) in 12-month graft biopsies in belatacept versus cyclosporin (CNI)-treated patients [Belatacept Evaluation of Nephroprotection and Efficacy as First-line Immunosuppression Trial (BENEFIT) study]. Seven years after kidney transplantation (KT), mean estimated glomerular filtration rate (eGFR), patient and graft survival were significantly higher with belatacept versus CNI treatment. The aim of this study was to determine whether the immunophenotypes of inflammatory and regulatory cell subsets infiltrating the grafts contribute to the BENEFIT's clinical findings a decade after KT. Twenty-three adult patients with functionally stable KT treated with belatacept and 10 treated with CNI were enrolled. Biopsies were analyzed by histomorphometry and immunohistochemistry for proliferation, senescence, apoptosis, inflammatory and regulatory cell markers in a blinded manner. Significantly lower percentages of inflammatory/fibrogenic cells [interleukin (IL)-22+ /Th17/Th2/M1 macrophages] were observed in patients treated with belatacept than in patients treated with CNI. By contrast, remarkably higher percentages of regulatory cells [Tregs /Bregs / plasmacytoid dendritic regulatory cells (pDCregs )/M2] were found in belatacept-treated patients than in CNI-treated patients. Conspicuously lower percentages of apoptosis and senescence and higher proliferation markers were found in belatacept-treated patients than in CNI-treated patients. Consequently, there was significantly more inflammation in the microvascular compartments as well as increased tubular atrophy and IF in CNI-treated patients. These findings strongly suggest that regulatory mechanisms, along with the absence of deleterious effects of CNI, contribute to the long-term graft histology and function stability in patients treated with belatacept.

Is Mexico Ready for Face Transplantation?

With the limitations of surgical reconstructive procedures, the growing number of gunshot wounds, burns, and work accidents in Mexico that result in complex facial deformities leaves only 1 option-face transplantation. The National Institute of Medical Sciences and Nutrition "Salvador Zubiran" (INCMNSZ) has performed transplants since 1971. We at INCMNSZ undertook the 1st bilateral upper-limb transplantation in Latin America in 2012. We are willing to continue in this manner toward conducting face transplantation at our institute. To this end, we identified and solved various challenges. The 1st challenge was acceptance and inclusion of vascularized composite allotransplantation (VCA) within general Mexican health law and approval of the face transplantation procedure. Subsequently, the health ministry provided a license to INCMNSZ to perform the procedure. The 2nd challenge concerned who would pay for the procedure. The costs will be paid by the patient (1st-party payer), social security institutions (2nd-party payers), and the health ministry (3rd-party payer). The 3rd challenge was to maintain ongoing surgical training of the team using cadavers. The fourth challenge was to locate donors; toward this end, we developed a campaign for promoting face donation in social media, making a comic book, and training organ and tissue coordinators to further VCA. Thus, INCMNSZ has the legal, administrative, medical, and surgical wherewithal to accomplish face transplantation.

Effect of Ramipril on Urinary Protein Excretion in Maintenance Renal Transplant Patients Converted to Sirolimus.

This prospective, randomized, double-blind, placebo-controlled study evaluated the effects of ramipril on urinary protein excretion in renal transplant patients treated with sirolimus following conversion from a calcineurin inhibitor. Patients received ramipril or placebo for up to 6 weeks before conversion and 52 weeks thereafter. Doses were increased if patients developed proteinuria (urinary protein/creatinine ratio ≥0.5); losartan was given as rescue therapy for persistent proteinuria. The primary end point was time to losartan initiation. Of 295 patients randomized, 264 met the criteria for sirolimus conversion (ramipril, 138; placebo, 126). At 52 weeks, the cumulative rate of losartan initiation was significantly lower with ramipril (6.2%) versus placebo (23.2%) (p < 0.001). No significant differences were observed between ramipril and placebo for change in glomerular filtration rate from baseline (p = 0.148) or in the number of patients with biopsy-confirmed acute rejection (13 vs. 5, respectively; p = 0.073). One patient in the placebo group died due to cerebrovascular accident. Treatment-emergent adverse events were consistent with the known safety profile of sirolimus and were not potentiated by ramipril co-administration. Ramipril was effective in reducing the incidence of proteinuria for up to 1 year following conversion to sirolimus in maintenance renal transplant patients.

Minor H antigen matches and mismatches are equally distributed among recipients with or without complications after HLA identical sibling renal transplantation.

Studies of the effect of minor H antigen mismatching on the outcome of renal transplantation are scarce and concern mainly single center studies. The International Histocompatibility and Immunogenetics Workshops (IHIW) provide a collaborative platform to execute crucial large studies. In collaboration with 16 laboratories of the IHIW, the role of 15 autosomal, 10 Y-chromosome encoded minor H antigens and 3 CD31 polymorphisms, was investigated in relation to the incidence of renal graft rejection and graft loss in 444 human leukocyte antigens (HLA)-identical sibling renal transplantations. Recipient and donor DNA samples were genotyped for the minor H antigens HA-1, HA-2, HA-3, HA-8, HB-1, ACC-1, ACC-2, SP110, PANE1, UGT2B17, C19Orf48, LB-ECGF-1, CTSH, LRH-1, LB-ADIR and HY. The correlation between minor H antigen mismatch and the primary outcome graft rejection or graft loss was statistically analyzed. The incidence of rejection was very low and no correlation was observed between one or more minor H antigen mismatch(es) and a rejection episode (n = 36), of which only eight resulted in graft loss. In summary, in our study cohort of 444 renal transplants, mismatching for neither autosomal nor HY minor H antigens correlate with rejection episodes or with graft loss.

Seroprevalence of Trypanosoma cruzi in kidney transplant donors and recipients in Mexico City.

Infectious diseases are common causes of morbidity and mortality among kidney transplant recipients. Chagas disease (CD) has been recognized as an emerging infectious complication of transplantation caused by the parasite Trypanosoma cruzi. CD is prevalent in Mexico, particularly in the southern coastal region. The impact on Mexican kidney transplant programs has not been previously studied prospectively. From 2009 through 2010, serum samples from 59 kidney transplant donors and 405 renal transplant recipients were screened for antibodies against T. cruzi. Serum was initially screened using a locally developed ELISA test; positive results were confirmed by an indirect immunofluorescense test, in accordance with Panamerican Health Organization/World Health Organization guidelines. None of the donors were seropositive for T. cruzi, while 8 (1.97%) kidney transplant recipients were confirmed to be seropositive for T. cruzi. None of them have developed clinical manifestations of CD, although specific screening of recipients was not performed. A prospective study is planned to define the epidemiology and outcome of CD among kidney transplant donors and recipients in Mexico more thoroughly.

Probability of deceased donor kidney transplantation based on % PRA.

UNLABELLED: Sensitization to HLA antigens creates an obstacle for the accessibility and success of kidney transplantation (KT). Highly sensitized patients have longer waiting times and some may never receive a KT. AIM: To determine the probability of patients on the deceased donor (DD) waiting list to receive a KT based on the panel reactive antibody percentage (% PRA) in our center. METHODS: The DD waiting list from our institution was analyzed from 01/05 to 08/12 documenting the clinical variables from donor and potential recipients (ABO blood group), lymphocyte cross-match [CxM (CDC-AHG)] results, highest % PRA determination, and time on the waiting list. The patients were classified into 4 groups based on the % PRA: 0%, 1-19%, 20-79% and 80-100%. The data was analyzed using odds ratio and logistic regression (significant p<0.05). RESULTS: 58 DD (F:M 34:24, ABO group O=35, A=13, B=10) and 179 potential recipients were analyzed (F:M 98:81, ABO group O=127, A=33, B=19, participating 4.2 ± 3.8 times with different donors to receive KT). The mean PRA for the whole group was 22 ± 32%, median [md] 0 (0-98). A total of 100 patients received KT (mean waiting time 2.2 ± 1.7 years, 12 days-7 years) and their mean % PRA was 11.6 ± 24, md 0 (0-94) vs. 31.4 ± 37 md 8.5 (0-98) in those who have not received a KT. An association between the % PRA group and KT (p<0.003) was observed. The probability of receiving KT with a 0% PRA vs. >0% was higher (OR 2.12, 1.17-3.84). There was no difference between the 0% vs. 1-19% group (OR 1); differences were observed between 0% vs. 20-79% (OR 2.5, 1.18-5.3) and 0% vs. 80-100% (OR 5, 1.67-14.9). For every percent increase in the PRA above 20%, the risk of not receiving a KT increased by 5% (1-9, p<0.01). CONCLUSIONS: The probability of receiving a DD kidney transplant is inversely related to the % PRA although a higher risk for not receiving a KT becomes evident with a PRA >20%.

Fever, haematuria, and acute graft dysfunction in renal transplant recipients secondary to adenovirus infection: two case reports.

We report two cases of adenoviral infection in kidney transplant recipients that presented with different clinical characteristics under similar demographic and posttransplant conditions. The first case presented with fever, gross haematuria, and acute graft dysfunction 15 days following renal transplantation. A graft biopsy, analyzed with immunohistochemistry, yielded negative results. However, the diagnosis was confirmed with blood and urine real-time PCR for adenovirus 3 days after the initial clinical manifestations. The immunosuppression dose was reduced, and ribavirin treatment was started, for which the patient quickly developed toxicity. Antiviral treatment allowed for transient response; however, a relapse occurred. The viral real-time PCR became negative upon immunosuppression reduction and administration of IVIG; graft function normalized. In the second case, the patient presented with fever and dysuria 1 month after transplantation. The initial imaging studies revealed graft enlargement and areas of hypoperfusion. In this case, the diagnosis was also confirmed with blood and urine real-time PCR for adenovirus 3 days after the initial clinical manifestations. Adenoviral nephritis was confirmed through a graft biopsy analyzed with light microscopy, immunohistochemistry, and PCR in frozen tissue. The immunosuppression dose was reduced, and IVIG was administered obtaining excellent clinical results along with a negative real-time PCR.

Infiltrating cellular pattern in kidney graft biopsies translates into forkhead box protein 3 up-regulation and p16INK4α senescence protein down-regulation in patients treated with belatacept compared to cyclosporin A.

Renal allograft survival is related directly to cell senescence. In the transplantation scenario many cellular events - participating as immunological and non-immunological factors - could contribute to accelerate this biological process, responsible for the ultimate fate of the graft. Mechanisms concerned in tolerance versus rejection are paramount in this outcome. For this reason, immunosuppressive treatment constitutes an extremely important decision to prevent organ dysfunction and, finally, graft loss. This study was conducted to document the proportion of CD4(+) /interleukin (IL)-17A(+) -, CD16(+) /indoleamine 2, 3-dioxygenase (IDO(+) )-, forkhead box protein P3 (FoxP3(+))-expressing cells, senescent cells (p16(INK) (4α)) and the percentage of interstitial fibrosis (IF) in graft biopsies of kidney transplant recipients participating in the BENEFIT (Bristol-Myers Squibb IM103008) study. CD4(+) /IL-17A(+) , CD16(+) /IDO(+), FoxP3(+) and p16(INK) (4α+) cells were evaluated by immunohistochemistry, and the percentage of IF by morphometry on graft biopsies obtained at time 0 (pre-implantation) and at 12 months post-transplant. Senescent cells and CD4(+) /IL-17A(+) cells were increased among graft biopsies in subjects receiving cyclosporin A (CsA) compared to those under belatacept treatment. Meanwhile, CD16(+) /IDO(+) and FoxP3(+) -expressing cells were lower in biopsies from CsA treatment compared to patients treated with Belatacept. Histological morphometric analyses disclosed more IF in 12-month CsA-treated patients in comparison to pre-implantation biopsy findings. Summing up, renal biopsies from patients receiving belatacept showed greater amounts of FoxP3(+) cells and lower amounts of CD4(+) /IL-17A(+) and senescent cells compared to patients under CsA treatment. Along with these findings, an increase in IF in annual CsA-treated-patients biopsies compared to pre-implantation and belatacept-treated patients were observed.

Three-year outcomes from BENEFIT, a randomized, active-controlled, parallel-group study in adult kidney transplant recipients.

The clinical profile of belatacept in kidney transplant recipients was evaluated to determine if earlier results in the BENEFIT study were sustained at 3 years. BENEFIT is a randomized 3 year, phase III study in adults receiving a kidney transplant from a living or standard criteria deceased donor. Patients were randomized to a more (MI) or less intensive (LI) regimen of belatacept, or cyclosporine. 471/666 patients completed ≥3 years of therapy. A total of 92% (MI), 92% (LI), and 89% (cyclosporine) of patients survived with a functioning graft. The mean calculated GFR (cGFR) was ∼21 mL/min/1.73 m(2) higher in the belatacept groups versus cyclosporine at year 3. From month 3 to month 36, the mean cGFR increased in the belatacept groups by +1.0 mL/min/1.73 m(2) /year (MI) and +1.2 mL/min/1.73 m(2) /year (LI) versus a decline of -2.0 mL/min/1.73 m(2) /year (cyclosporine). One cyclosporine-treated patient experienced acute rejection between year 2 and year 3. There were no new safety signals and no new posttransplant lymphoproliferative disorder (PTLD) cases after month 18. Belatacept-treated patients maintained a high rate of patient and graft survival that was comparable to cyclosporine-treated patients, despite an early increased occurrence of acute rejection and PTLD.

A comparative study of the traditional method, and a point-score system for allocation of deceased-donor kidneys: a national multicenter study in Mexico.

BACKGROUND: The National Transplant Center in Mexico has ruled that deceased-donor kidney allocation is a function of each hospital's Internal Transplant Committee. The aim of this study was to compare and analyze results for of the traditional method and a point-score system in the allocation of deceased patient's kidneys. METHODS: The 12 major kidney transplant centers in the country having a deceased-donor program were invited to participate. Only 3 of them replied to the invitation during 2010. A point-score system was proposed to them, comprising blood group, waiting list time, HLA type, and donor and recipient ages. Once the final recipient was chosen, an explanation of reasons for the choice was requested. Thirty-eight transplants were presented. Kappa coefficient was used to measure degree of agreement in both allocation systems. Organs donated for transplantation came from patients between 4 and 54 years old, including 52% female, 52% O+ blood type, 31% A+, and 11% B+, 44% cranial-encephalic trauma, and 44% brain hemorrhage. RESULTS: Global agreement was 52.6% (kappa = 0.343), and partial agreement was 76.3% (weighted kappa = 0.204), assigning more intensity to extreme values, but with a lower correlation index. A more intense agreement, without discriminating by hospital, was found for "A" category (blood group), followed by "B" category (waiting list time). DISCUSSION: Taking into consideration the determining factors for long-term graft survival, it is indispensable to include criteria such as donor and recipient ages and HLA typife in the allocation process. This first draft of a point-score system in organ allocation included waiting list time, blood group, urgency related to vascular/peritoneal access for dialysis, clinical condition, donor/recipient age ratio, and HLA antigenic compatibility.

Immune response after rabies vaccine in a kidney transplant recipient.

A 48-year-old male kidney-transplant recipient was bitten by a rabid dog. His immunosuppressive treatment consisted of cyclosporine 60 mg b.i.d., mycophenolate mofetil (MMF) 250 mg t.i.d., and prednisone 5 mg. After wound care, he received 5 doses of purified vero cell rabies vaccine on days 0, 3, 7, 14, and 28, and human rabies immunoglobulin, according to international guidelines. Adequate levels of rabies virus neutralizing antibodies were observed after the administration of the third vaccine dose. However, a decrease of antibody titer was detected by day 28. Immunosuppressive medication was minimized, withdrawing MMF and reducing the dose of cyclosporine. Booster doses of the same vaccine were administered on days 38, 41, 45, 52, and 66. Adequate neutralizing antibody response was recovered during the ensuing 12 months, under reduced immunosuppression. Nineteen months after the incident, the patient remains with good graft function and is asymptomatic for rabies. It remains to be determined whether the attained immune response was either the result of the booster vaccinations or the reduction of immunosuppression alone. Nevertheless, such an outcome would have been possible only with the combined management strategy implemented.

Association of the metabolic syndrome and long-term renal function in kidney donors.

BACKGROUND: Metabolic syndrome (MetS) may represent risk factor for long-term renal function of kidneys from living donors. The aim of this study was to evaluate the impact of MetS on renal function in donors. METHODS: Data regarding the presence or absence of MetS and renal function, as assessed by estimated glomerular filtration rate (eGFR) were obtained from 140 kidney donors before nephrectomy (BN) and at follow-up (AF). Donors were divided into those with (group 1; n =28) versus without MetS (group 2; n = 112). RESULTS: Comparing the groups, we observed a significantly greater reduction in eGFR among the group with MetS BN versus AF 27.5% (19.3-33.0) versus 21.4% (9.6-34.1 P = .02) respectively using a Cox regression model, including age, gender, serum uric acid, body mass index (BMI), and basal eGFR, MetS BN (hazard ratio = 2.2; 95% confidence interval [CI], 1.21-4.01; p = .01) was an independent factor associated with a greater risk of a-eGFR <70 mL/min/1.73 m(2) at follow-up (P < .001). Additionally, age (hazard ratio = 1.03%; 95% CI, 1.01-1.06; P < .001), and female gender (hazard ratio = 1.86; 95% CI, 1.03-3.36; P = .03) were associated with a greater decrease in eGFR. Individuals with MetS BN showed a GFR <70 mL/min/1.73 m(2) at significantly shorter follow-up time (5.6 ± 0.8 years) versus persons without MetS (12.8 ± 1.0 years; P = .001) CONCLUSION: Kidney donors with MetS BN experiment a significantly greater decrease in eGFR at follow-up.

Ethical challenges in transplant practice in Latin America: the Aguascalientes Document.

Organ transplants are currently an alternative treatment for a growing number of diseases, which were previously considered terminal. Bioethics has played an important role since the advent of this surgical technique, mainly in defining death criteria and the optimum transplantation conditions. This issue continues being a universal focal point, mainly concerning the equity of access to transplantation, criteria for assigning deceased-donor organs, living-donor safety, risk of commercial trade, fair access to high-quality immunosuppressive drugs and organ transplant legislation. These problems are characteristic of Latin America and the Caribbean, and were the driving force behind the First Latin American Bioethics and Transplant Forum, sponsored by the Latin American and Caribbean Transplant Society (STALYC), and all the transplant societies from subsidiary countries. The "Document of Aguascalientes" is a collection of all the ideas and opinions that were proposed during round tables and analyses. The document is divided into four sections: 1) living donor; 2) organ trading and transplant tourism; 3) the state role in legislation, transplant distribution and coverage; and 4) access to and quality of immunosuppression. The Bioethics and Transplant Forum was created to analyse and find solutions for this complex issue. The "Document of Aguascalientes" aims to serve as an instrument of expression and a vehicle for the ideas put forward during the Forum, so that they can act as transplant practice guidelines in Latin America.

National survey carried out by the Mexican Society of Transplantation in 2009 regarding deceased-donor kidney allocation.

BACKGROUND: The Mexican Health Law stipulated that the criteria to be taken into account for deceased donor kidney allocation should include the following: "seriousness of recipient's condition, opportunity of transplant, expected benefits, compatibility with recipient, and all other accepted medical criteria." The practical application of these criteria has been perceived by several members of transplantation committees as allowing inequity in kidney allocation. The aims of this study were to learn the opinions of transplantation committees regarding current national allocation policies, and to obtain their opinions about the advantages of a point-score system. METHODS: A prepared questionnaire was validated with the collaboration of a team of transplantation physicians from the Mexican Society of Transplantation (MST). Ninety members of the Society, who represent transplantation groups were invited by mail to participate in the survey. RESULTS: We received 70 answered questionnaires, including 54 that represented the views of their respective internal transplantation committees. In agreement with the legislation and allocation policies currently in force were 50% of responders; however, 60% believed that a point-score system for organ allocation should be mandatory and 75% believed that only patients without a possible live donor should be included on the waiting list to compete for a deceased donor kidney. Also, 84% believed that only patients with a complete pre-transplant protocol, including recent viral serology, as well as clinically relevant pre-transplant evaluations by other specialists such as cardiology, psychiatry/psychology and urology should qualify for allocation of deceased donor organs; 76% believed that patients who compete for a deceased donor organ must have permanent support for immunosuppressive drugs as well as for short-term and long-term medical care. CONCLUSION: The answers gathered through this survey pointed out the necessity for continuous coordinated work between healthcare authorities and members of the MST to achieve the best guidelines for allocation of deceased donor kidneys including a point-score system.

Individualizing early use of sirolimus in renal transplantation.

One of the main goals in the current care of kidney transplant recipients is to extend long-term graft survival. Efficacious immunosuppressive agents devoid of nephrotoxicity are needed. In human clinical transplantation, sirolimus combined with other immunosuppressive drugs has proven to be a powerful immunosuppressant capable of preventing acute graft rejection, as well as of improving renal function, renal histology, and graft survival when compared with immunosuppressive regimens that include calcineurin inhibitors. The valuable experience gained through many clinical studies allows clinicians to plan sirolimus use. We present a review of the clinical experience and literature review on the use of sirolimus in the first 12 months posttransplantation.

High levels of IDO-expressing CD16+ peripheral cells, and Tregs in graft biopsies from kidney transplant recipients under belatacept treatment.

BACKGROUND: Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-degrading enzyme that suppresses T-lymphocyte activity. Costimulation blockade through CTLA4lg increases IDO in antigen-presenting cells. The suppressive effect of IDO is thought to be mediated by Foxp3+CD4+CD25+ regulatory T-cells (Tregs). OBJECTIVE: In this descriptive study, we evaluated the percentage of IDO-expressing peripheral cell subpopulations as well as Tregs in 27 stable kidney transplant recipients receiving either belatacept (LEA29Y), a daughter compound of abatacept (CTLA4lg; n = 19) or cyclosporine (n = 8). METHODS: Blood samples were obtained at 24 ± 2 months (belatacept) and 23 ± 6 months (cyclosporine) of treatment. Intracellular IDO was analyzed by flow cytometry in CD14+, CD11c+, CD16+, CD56+, and CD8+ cell subpopulations. Tregs were assessed by intracellular Foxp3 detection in CD4+CD25+ cells. CD3+, CD4+, CD8+, CD20+, CD68+, IDO+, and Foxp3+ cells were evaluated by immunohistochemistry on graft biopsies obtained preimplantation, at 12 months posttransplant, and in subjects with dysfunction during the first 12 months. RESULTS: Only percentages of CD16+/IDO+-expressing peripheral monocytes were significantly increased among the group receiving belatacept. No differences were observed in peripheral Tregs between the groups. In contrast, higher percentages of Tregs, CD4+, CD8+, and CD68+ cells were noted in dysfunction and at 12 months vs baseline among graft biopsies in subjects receiving belatacept, and also among dysfunction cohorts of belatacept vs Cyclosporine treatment. CONCLUSION: Patients receiving belatacept showed greater amounts of peripheral blood CD16+/IDO+ cells and Tregs on graft biopsies than those under cyclosporine treatment.

Clinical insights for cancer outcomes in renal transplant patients.

The long-term fate of renal transplant recipients has remained relatively unchanged over the last 15 years. The cumulative, chronic effects of immunosuppression contribute, to a great extent, to the higher, premature mortality rates linked to cardiovascular disease and malignancy observed in this patient population. Immunosuppression disrupts both antitumor surveillance and antiviral activities, and oncogenic viruses predispose to specific malignancies. Further, some drugs promote carcinogenesis by mechanisms independent of their immunosuppressive effects. In vitro studies have shown that calcineurin inhibitors (CNIs) promote tumor progression by a transforming growth factor-ß-dependent mechanism. In contrast, in vivo mouse models have demonstrated that mammalian target of rapamycin (mTOR) inhibitors inhibit metastatic tumor growth and angiogenesis. The association between mTOR-inhibitor and reduced malignancy has been demonstrated in several studies. United Network for Organ Sharing registry data demonstrate that an mTOR-inhibitor either with or without a CNI, is associated with a reduced incidence of tumors compared to regimens that do not utilize mTOR-inhibitor Five years after renal transplantation, patients in the Rapamune Maintenance Regimen study who received sirolimus (SRL)-based CNI-free therapy after cyclosporine (CsA) withdrawal at 3 months showed a reduced incidence of malignancy compared with those who continued a regimen including (CsA) In the CONVERT study, patients who converted to SRL displayed a significantly lower malignancy rate (3.8%) at 24 months compared with those who continued CNI based therapy (11%; P < .001). A randomized, prospective study to evaluate the effect of conversion to SRL from a CNI, compared with continued CNI, showed that SRL was associated with a lower rate of nonmelanoma skin cancer (NMSC) and a longer time to first biopsy-confirmed new NMSC. An mTOR-inhibitor CNI-free regimen should be considered for transplant recipients at high risk for cancer development and for those who develop malignancies over the posttransplant course.

Time of occurrence of kidney acute antibody-mediated allograft rejection/acute cellular rejection and cell senescence: implications for function outcome.

BACKGROUND: Late versus early acute antibody-mediated rejection (AAMR) or acute cellular rejection (ACR) episodes are associated with poorer kidney function and graft survival. We explored whether cell senescence upon detection of AAMR ± ACR contributes to these results. METHODS: We reviewed the renal transplant database of 2 Institutions. Biopsies performed for acute graft dysfunction from January 2000 to March 2007 were analyzed for morphological criteria of AAMR with or without ACR (n = 17 from 17 patients). Immunoperoxidase staining for p16(INK4B) was performed on the remaining paraffin-embedded tissue in 9 of 17 cases. The average number of positive cells/high power field (HPF) was calculated in every case. Cases with rejection were grouped according to the time of presentation: early (<3 months n = 8) versus late (>3 months; n = 9). Graft function was obtained using the Modification of Diet in Renal Disease (mDRD) glomerular filtration rate estimate (eGFR) before, during rejection, and at the last visit, to calculate ΔeGFR. RESULTS: Nuclear expression of p16(INK4B) was 12.2 ± 11.3 cells/HPF in 4 of 8 biopsies performed at a median of 23 (range = 4-80) days (early AAMR ± ACR), and 59.8 ± 51.3 cells/HPF in 5 of 9 biopsies performed at a median of 1171 (range = 279-3210) days (late AAMR ± ACR). eGFR before rejection was 48.5 ± 7.6 mL/min, and 43.7 ± 4.3 mL/min for early and late rejection episodes, respectively (P = not significant [NS]). ΔeGFR of 12.5 ± 25.9 mL/min (early rejection), and -13.7 ± -12.3 mL/min (late rejection), versus last follow-up visit (P = .02) occurred at a median of 143.9 ± 94.1 and 69.6 ± 35.1 weeks after the rejection episodes, respectively. CONCLUSIONS: Even though the number of biopsies analyzed for p16(INK4a) was small, it was evident that the number of cells expressing this marker of senescence was higher among biopsy specimens obtained with late rejection episodes. This finding suggests the presence of injuries prior to the rejection episode. The significantly lower eGFR at last follow-up in the late rejection group may translate to a reduced capacity of the repair process to sustain nephron function.

Renal grafts with multiple arteries: a relative contraindication for a renal transplant?

INTRODUCTION: Advances in surgical techniques had achieved good outcomes in renal transplantation. There has been controversy with respect to the impact of multiple arteries on the outcome of the renal transplantations. OBJECTIVES: The objectives of this study were to examine the renal function and incidence of complications among grafts with one versus two or more arteries. MATERIALS AND METHODS: We evaluated 86 patients with renal transplantations between January 2006 and January 2008 as a retrospective comparative study. The patients were stratified according to the number of renal graft arteries: group 1 had one artery (n = 66); group 2, two or more arteries (n = 16). RESULTS: The warm ischemia time was shorter among group 1 compared with group 2 (P < .03). There were significant differences between the groups with respect to mean blood pressure at 1 year (P < .04). The kidney biopsies after 1-year follow-up did not show any difference. CONCLUSION: We considered that the presence of anatomic variations was not a contraindication for renal transplantation, but that it is necessary to continue our follow-up to determine the real impact of these variations on graft and patient survivals.

Risk factors for Banff borderline acute rejection in protocol biopsies and effect on renal graft function.

INTRODUCTION: The interpretation and handling of Banff borderline acute rejection observed in protocol biopsies from patients with stable renal function continues to be controversial. Our objective was to identify the risk factors for borderline acute rejection on 1-year protocol biopsies and to evaluate their effect on renal graft function after 2 years' follow-up. METHODS: We included 82 kidney transplant recipients (KTR), who underwent 1-year protocol biopsies with normal or stable graft function. All KTR had follow-up of at least 2 years posttransplantation. We formed three groups: (1) KTR with a normal biopsy, (2) KTR with borderline changes, and (3) KTR with interstitial fibrosis/tubular atrophy (IF/TA). We searched for risk factors related to borderline injury. The main outcome to evaluate was renal function at 1 month, at protocol biopsy, and 2 years posttransplant. RESULTS: The 82 patients included in this study showed no differences in immunosuppression, gender, etiology of renal failure, or percentage of panel-reactive antibodies. The risk factors associated with borderline lesions were: at least one biopsy due to allograft dysfunction and acute rejection events during the first year posttransplant (P = .011 and P = .021, respectively). Increased serum creatinine and estimated glomerular filtration rate decline were greater among the borderline lesion than the normal group, but similar to patients with IF/TA. CONCLUSION: Renal function decline was greater among borderline and IF/TA groups. However, the sum of insults, and not only the borderline injury itself, produces greater declines in renal function with greater risk for graft loss.