Prediction of kidney transplant outcome by donor quality scoring systems: expanded criteria donor and deceased donor score.

Due to disparity between organ supply and demand, use of kidneys from suboptimal donors has become increasingly common. Several donor quality systems have been developed to identify kidneys with an increased risk for graft dysfunction and loss. The purpose of our study was to compare the utility of deceased donor score (DDS) and expanded criteria donor (ECD) status to predict kidney transplant outcomes in a single center. We analysed 280 deceased donor renal transplantation procedures, collecting data from the prospectively maintained institutional database. Kidney transplant outcome variable included delayed graft function, 1-year glomerular filtration rate (GFR1y), and death-censored graft loss (DCGL). Kidneys were obtained from marginal donors in 45.7% of transplant recipients by DDS and in 24.9% by ECD. DDS-defined marginal donors suffered delayed graft function (DGF) more frequently than nonmarginal donors (40.8% vs 25.0%; P = .006), whereas ECD did not develop DGF at a greater rate. GFR1Y was significantly worse among patients receiving kidneys from marginal donors: DDS 40.3 ± 12.9 vs 57.7 ± 19.4 mL/min/1.73 m(2) (P < .001) and ECD 39.4 ± 14.1 vs 53.8 ± 19.1 mL/min/1.73 m(2) (P < .0001). The most severe donor category defined by DDS (grade D) showed an independently worse death-censored graft survival hazard rate [HR] 2.661, 95% confidence interval [CI], 1.076-6.582; P = .034). DDS and ECD scoring systems are based on donor information available at the time of transplantation that predict 1-year graft function. Moreover in our center, DDS was better to predict DGF and death-censored graft survival than ECD.

New-onset diabetes after transplantation: drug-related risk factors.

INTRODUCTION: New-onset diabetes after transplantation (NODAT), an important complication of renal transplantation leads to reduced graft function and increased patient morbidity and mortality. Because of its high incidence and immense impact on clinical outcomes, prevention of NODAT is highly desirable. Several modifiable and nonmodifiable risk factors for NODAT have been described. The aim of this study was to analyze the influence of various drugs on the development of NODAT during the first year. METHODS: A retrospective analysis was performed on 303 adult kidney transplant recipients free of previously known diabetes. NODAT was defined as a fasting plasma glucose level ≥ 126 mg/dL confirmed by repeat testing on a different day. We excluded patients with transiently elevated fasting plasma glucose during the first 3 months. RESULTS: NODAT was diagnosed in 37 recipients (12.2%). Univariate analysis identified several variables related to NODAT: recipient age (P < .001), body mass index (P < .001), donor age (P = .005), family history of diabetes (P < .001), statin use (P = .005), diuretic use (P = .040) and tacrolimus therapy (P = .029). After multivariate analysis, recipient age (relative risk [RR] = 1.060, 95% confidence interval [CI] 1.019- 1.102, P = .004), family history of diabetes (RR = 3.562, 95% CI 1.574-8.058, P = .002), smoking habit (RR 2.514, 95% CI 1.118-5.655, P = .026) and diuretic use (RR = 2.496, 95% CI 1.087-5.733, P = .031) were independently associated with NODAT development. CONCLUSIONS: In our population of kidney transplant recipients, the main nonmodifiable risk factors for NODAT were recipient age and a family history of diabetes. Diuretic use was a modifiable risk factor associated with the development of NODAT. To reduce NODAT incidence, it is necessary to consider not only immunosuppressive therapy, but also concomitant drugs such as diuretics.

Prediction of delayed graft function by means of a novel web-based calculator: a single-center experience.

Renal failure persisting after renal transplant is known as delayed graft function (DGF). DGF predisposes the graft to acute rejection and increases the risk of graft loss. In 2010, Irish et al. developed a new model designed to predict DGF risk. This model was used to program a web-based DGF risk calculator, which can be accessed via http://www.transplantcalculator.com . The predictive performance of this score has not been tested in a different population. We analyzed 342 deceased-donor adult renal transplants performed in our hospital. Individual and population DGF risk was assessed using the web-based calculator. The area under the ROC curve to predict DGF was 0.710 (95% CI 0.653-0.767, p < 0.001). The "goodness-of-fit" test demonstrates that the DGF risk was well calibrated (p = 0.309). Graft survival was significantly better for patients with a lower DGF risk (5-year survival 71.1% vs. 60.1%, log rank p = 0.036). The model performed well with good discrimination ability and good calibration to predict DGF in a single transplant center. Using the web-based DGF calculator, we can predict the risk of developing DGF with a moderate to high degree of certainty only by using information available at the time of transplantation.

Early prediction of new-onset diabetes mellitus by fifth-day fasting plasma glucose, pulse pressure, and proteinuria.

Renal transplant recipients are at high risk of cardiovascular disease (CVD). New-onset diabetes mellitus after transplantation (NODAT) contributes to the risk of CVD, reducing graft and patient survival. To improve outcome of kidney transplant recipients, it is of great interest to identify those patients who will develop NODAT. The aim of our study was to explore the predictive value of fifth-day fasting plasma glucose (FPG), third-month proteinuria, and pulse pressure (PP) for NODAT development. We analyzed 282 non-previously-diabetic kidney transplants in our center. Fifth-day FPG, PP, and third-month 24-hour proteinuria were collected. NODAT was defined at month 12 according to the "consensus guidelines": symptoms of diabetes plus casual glucose concentrations ≥ 200 mg/dL or FPG ≥ 126 mg/dL. Some 46 patients (16.3%) developed NODAT at month 12. Fifth-day FPG (133 ± 35 vs 108 ± 16 mg/dL, P < .001) and PP (57 ± 17 vs 49 ± 15 mm Hg, P = .007) were significantly higher in patients at risk for NODAT, but there was no difference in third-month proteinuria (652 ± 959 vs 472 ± 1336 mg, P = .390). A multivariate regression model showed an increased risk for NODAT associated with recipient age, body mass index, smoking habit, and a fifth-day FPG ≥ 126 mg/dL (relative risk 4.784, 95% confidence interval 2.121-10.788, P = .0002). The negative predictive value of a fifth-day FPG ≥ 126 mg/dL for predicting 1-year NODAT was 89.4%. Fifth-day FPG was independently related to NODAT development. The detection of a fifth-day FPG ≥ 126 mg/dL increases the risk of suffering NODAT more than 4 times. Fifth-day FPG < 126 mg/dL allows us to identify a transplant population with a low risk (near 10%) for NODAT.

Exploring the opinion of CKD patients on dialysis regarding end-of-life and Advance Care Planning.

Advance care planning (ACP) and the subsequent advance directive document (ADD), previously known as "living wills", have not been widely used in Spain. The Ethics Group from the Spanish Society of Nephrology has developed a survey in order to investigate the opinion of dialysis patients regarding the ADD and end-of-life care. Patients received documentation explaining ACP and filled out a survey about their familiarity with and approval of the ADD. Seven hospital dialysis centres participated in the study for a total of 416 active dialysis patients. Questionnaires were distributed to 263 patients, 154 of which answered (69.2% completed them without assistance). The rates for ADD implementation (7.9%) and designation of a representative person (6.6%) were very low. Most of the patients clearly expressed their wishes about irreversible coma, vegetative state, dementia and untreatable disease. More than 65% did not want mechanical ventilation, chronic dialysis, tube feeding or resuscitation if cardiorespiratory arrest occurred. They reported that an ADD could be done before starting dialysis but most thought that it should be offered only to those who requested it (65% vs 34%). In conclusion, patients have clear wishes about end-of-life care, although these desires had not been documented due to the very low implementation of the ADD.

[Detection of latent tuberculosis infection in peritoneal dialysis patients: new methods]. / Detección de la infección tuberculosa latente en pacientes en diálisis peritoneal: Nuevos métodos.

OBJECTIVE: The risk for tuberculosis (TB) is increased in patients with chronic renal failure and dialysis. Tuberculin skin test (TST) is the classical diagnostic method for screening despite its low sensitivity. New methods based on interferon-gamma have been developed. The aim of this study was to evaluate if Quantiferon® TB-gold In Tube (QFT-GIT) could be useful in the diagnosis of TB infection in patients on peritoneal dialysis (PD). PATIENTS AND METHODS: Fifty-four patients on PD were included in the study. They were evaluated for latent tuberculosis with QFT-GIT, TST and an assessment by an expert pulmonologist using patient's medical history and x-rays. Agreement between test results was determined. RESULTS: The prevalence of a positive TST was 29.6% for the first test and 31.5% for the second (booster effect). A positive chest x-ray increased the rate of detection of patients with latent TB infection up to 42.6% and the expert physician's evaluation to 44.4%. The correlation between QFT-GIT and TST was fair (k=0.36; P=.006), as it was between TST and expert physician's evaluation (k=0.257; P=.06). CONCLUSIONS: According to our experience QFT-GIT represents an important advantage in the diagnosis of latent TB infection in chronic renal failure patients on PD. It may complement but not replace TST.

Elevated serum gamma-glutamyltransferase and hypomagnesemia are not related with new-onset diabetes after transplantation.

BACKGROUND: New-onset diabetes mellitus after transplantation (NODAT) contributes to the risk of cardiovascular disease (CVD) and infection, reducing graft and patient survival in kidney transplant recipients. To reduce CVD and improve outcomes of kidney transplant recipients, it is of great interest to more precisely elucidate the risk factors that contribute to the development of NODAT. A previous study reported that hypomagnesemia is an independent predictor of NODAT. Elevated gamma-glutamyltransferase (GGT) activity increases the risk of incident type 2 diabetes in the general population. The objective of this study was to determine whether magnesium (Mg) and GGT were risk factors for NODAT among our population of kidney transplant recipients. METHODS: We retrospectively analyzed 205 non-previously diabetic kidney transplant recipients. GGT was measured before transplantation as well as at months 1, 2, and 12. Mg was measured at months 1, 2, and 12. NODAT was defined at month 12 and at the end of follow-up according to the "2003 international consensus guidelines." RESULTS: Although 36 patients (17.5%) developed NODAT at month 12, 55 patients (26.8%) displayed it at the end of follow-up. We did not observe any significant difference, either in mean Mg (month 1, 1.73±0.24 vs 1.75±0.30 [P=.824]; month 2, 1.71±0.22 vs 1.68±0.26 [P=.565]; month 12, 1.77±0.27 vs 1.80±0.24 [P=.596]) or GGT values (pretransplantation, 32 ± 27 vs 33±85 [P=.866]; month 1:39±24 vs 48±70 [P=.452]; month 2, 53±96 vs 48±83 [P=.739]; month 12, 40±37 vs 38±53 [P=.830]) between NODAT and non-NODAT patients at month 12 or at the end of follow-up. CONCLUSION: Hypomagnesemia and high GGT activity were not risk factors for NODAT development in kidney transplant recipients.

Expanding criteria for peritoneal dialysis use.

The end stage renal disease population is growing all around the world. Most of these patients will need any kind of renal replacement treatment: renal transplantation, hemodialysis or peritoneal dialysis. Treatment of renal failure is costly and many analyses demonstrate that home based dialysis is the cheapest. In spite of social, clinical and economical advantages of peritoneal dialysis (PD), it is an underutilized modality of renal treatment. Low incidence and prevalence of PD as a renal replacement therapy is still a truth. Many factors influence that scarce use; nowadays there are countries which are making changes in their health systems in an effort to enhance its use. The following review presents the current situation of the use of peritoneal dialysis, its costs, complications and possible improvements to enhance its use.

Analysis of peritoneal leukocyte population with different dialysis fluids.

Uremic patients have leukocyte defects. In peritoneal dialysis patients some alterations could be induced by dialysis fluids. We analyzed the changes in immune cells (blood and peritoneal effluent), with the use of three solutions with different biocompatibility. We included 21 patients, 9 on 1 exchange/day icodextrin and 12 with lactate-buffered solutions. A cytometric study (cell subsets, activation markers and toll-like receptors) was performed. In 12 it was repeated after 3 months switch to a low-glucose degradation product (GDP) fluid. With lactate fluids, we observed B-lymphopenia, increase of T-cells and T-lymphocyte activation. In peritoneal effluent more monocytes and activation markers related to blood were found with conventional fluids. Icodextrin induced an increase of blood natural-killer cells, B-lymphocytes and CD8+CD38+ compared with lactate-buffered solution. In peritoneum more monocytes and less B-lymphocytes were found with icodextrin compared with biocompatible solution. Low-GDP fluid induced a decrease in lymphocyte activation markers (blood and effluent). The most biocompatible solution (low-GDP) induced the lowest expression of peritoneal monocytes and TLR4. Low-GDP solutions preserve peritoneum immune defences better, which could be important to avoid peritonitis and preserve peritoneal function. Although we found an association between TLR4 expression and biocompatibility, further investigations are needed in order to determine if such molecule could be a marker of peritoneum dysfunction.

[Changes in the pre-transplant bone-mineral metabolism do not affect the initial progress of the renal graft]. / Las alteraciones del metabolismo óseo-mineral pretrasplante no influyen en la evolución inicial del injerto renal.

BACKGROUND: Abnormalities in serum calcium, phosphate, and Parathyroid Hormone (PTH) concentrations are common in patients with chronic kidney disease and have been associated with increased morbidity and mortality. One of the most common problems in the first weeks after renal transplantation is Delayed Graft Function (DGF). There are several well-known risk factors for DGF development, but the role of calcium phosphate-PTH homeostasis as a risk factor for early graft dysfunction is controversial. This issue was addressed in the current study. METHODS: Pretransplant PTH, calcium and phosphate values were gathered in 449 patients that received a renal transplant in our center between 1994 and 2007. Other variables expected to influence the risk for delayed graft function were included from the clinical charts. RESULTS: The incidence of DGF was 27.3%. DGF development was significantly associated with recipient age, type and need of renal replacement therapy, peak panel reactive antibodies, transfusion number and donor age. There were no significant differences in the mean pretransplant values of calcium (9.4 +/- 1.0 vs. 9.5 +/- 0.9 mg/dl, p = 0.667), phosphate (5.7 +/- 1.8 vs. 5.5 +/- 1.5 mg/dl, p = 0.457), calcium-phosphate product (53.5 +/- 17.2 vs. 51.8 +/- 14.6 mg(2)/dl(2), p = 0.413) and PTH (315 +/- 312 vs. 340 +/- 350 pg/ml, p = 0.530) between patients with and without DGF. CONCLUSIONS: In our study population pretransplant serum PTH, calcium and phosphorus levels have no influence on the risk for DGF.

The position of the peritoneal dialysis catheter is not essential for a correct performance.

The success of chronic peritoneal dialysis (PD) is a well-functioning catheter. It is recommended to place the tip of PD access in the intraabdominal deep pelvic area. The authors' objectives were to prove if the PD device should be necessarily located in the pelvic area to function properly, and if the X-ray exploration should be compulsory when blinded implantation technique is used. 42 stable patients on PD were included in the study, infusion and drainage times were recorded and an abdominal X-ray was performed at the same time. Catheter was correctly located in 25 (59.5%) cases and in 17 (40.5%) it was malpositioned. We observed that there were no differences in infusion times, but in the first group drainage was faster than in the second although not significant: infusion 10.5 vs. 10.6 minutes and drainage 14.7 vs. 15.8 minutes. These clinical observations support the fact that catheters' function would not necessarily depend on its intraabdominal position and that a radiological exploration should not be mandatory.

Venous graft thrombosis in patients on peritoneal dialysis before transplantation.

BACKGROUND: It has been described that patients on peritoneal dialysis (PD) suffer from thrombotic events (vascular access, deep venous thrombosis, and graft thrombosis) more frequently after transplantation than other recipients. We analyzed the incidence of allograft thrombosis among patients transplanted in a 6-year period (January 1, 2000, to December 31, 2005) to identify etiological factors, such as inherited thrombophilia. MATERIALS AND METHODS: We performed 197 renal transplants in 189 patients, including 115 who had been on hemodialysis (HD), 44 on PD, and 30 preemptive. We recorded immunological and demographic data, studied graft and patient survivals, and evaluated the hypercoagulable state of those who experienced graft thrombosis. RESULTS: The mean age of the patients at transplantation was 49 years. There were no demographic or immunological differences between the three groups of patients, except for the number of previous blood transfusions and panel reactive antibodies (PRA) levels. Forty-seven grafts were lost in the first year; 14 suffered venous thrombosis, and there were 10 acute rejection epidoses (ARE), 7 death-censored graft failures, 3 chronic allograft nephropathies (CAN), 6 primary nonfunctions, 5 removed due to infection, 1 primary disease relapse, and 1 hemolytic-uremic syndrome. Of the 14 cases of thrombosis in 12 patients, 10 had been on PD and 4 on HD immediately before transplant. One-year graft and patient survivals were similar: 74% HD, 68% PD, 86% preemptive, and 93% HD, 95% PD, and 96% preemptive, respectively. The hypercoagulable state showed inherited thrombophilia patterns in some cases, but most of them were normal. CONCLUSION: Renal graft thrombosis was responsible for graft lost in PD patients within the first year, while in the HD group it was ARE and in the preemptive cohort, death with a functioning graft. The hypercoagulable state pretransplant should be more accurately studied to identify thrombotic factors other than those which are inherited.

Cytokine polymorphisms and risk of infection after kidney transplantation.

INTRODUCTION: Infection remains a significant cause of morbidity and mortality after solid organ transplantation. Genetic background has an influence on the incidence of infection. The aim of our study was to analyze the relationship between cytokine polymorphisms and infection in our kidney transplant recipients. METHODS: DNA from 255 kidney transplant recipients was isolated routinely. Polymerase chain reaction sequence-specific primer was performed using commercially available cytokine genotyping primer packs to determine polymorphisms of interleukin (IL)-10, transforming growth factor-beta, tumor necrosis factor-alpha, interferon-gamma, IL-6, IL-4, IL-2, IL-12, IL-4R alpha, IL-1RA, IL-1R, IL-1 beta, and IL-1 alpha. The appearance and number of infections within the first year after transplantation were identified retrospectively. RESULTS: One hundred twenty-two patients experienced at least one episode of infection in the first year after transplant. The frequency of the -511 IL-1beta CC genotype and the frequencies of the -1188 IL-12 CA and CC genotypes were significantly higher among the infected patients compared with the noninfected patients. We failed to observe significant differences in the genotype distribution of the other analyzed cytokines regarding the incidence of infection. After adjusting, recipient IL-1beta (-511 CC) genotype (relative risk [RR] 2.67, 95% confidence interval (CI) 1.30 to 5.49, P = .007) and recipient IL-12 (-1188 CA and CC) genotypes (RR 2.57, 95% CI 1.22 to 5.38, P = .012) predicted independently the risk of infection in the first year after kidney transplantation. CONCLUSION: Kidney transplant recipients with -511 IL-1beta CC genotype or with -1188 IL-12 CA and CC genotypes were at higher risk of developing infections in the first year after transplantation. Patients with genetic susceptibility to infection may benefit from less potent immunosuppressive therapy and more intense preventive measures.

Calcineurin inhibitors affect circulating regulatory T cells in stable renal transplant recipients.

INTRODUCTION: Immunosuppression, although crucial for short-term management, has been described in renal transplantation to be a major hurdle for long-term graft survival. Efforts have been directed at achieving a true state of allotolerance, thereby reducing the load of immunosuppression. Recently, increased frequencies of CD4(+)CD25(high) regulatory T cells (Tregs) have been described as an additional mechanism to induce alloimmune tolerance. MATERIALS AND METHODS: We assessed 64 renal transplant recipients with stable renal function for at least 1 year, divided into two groups: one composed of patients receiving rapamycin but not calcineurin inhibitors (CNIs), and another, of those receiving CNIs but not rapamycin. RESULTS: We demonstrated that T cells with a regulatory phenotype were decreased in peripheral blood of renal transplant recipients under CNI therapy compared to those who were CNI-free. The Tregs in our patients showed a modest association with renal function as measured by the delta serum creatinine, which was not significant. CONCLUSIONS: CNIs, but not rapamycin, reduce the frequencies of circulating Tregs in renal transplant recipients. The use of rapamycin might be further exploited in strategies reducing immunosuppression in renal transplantation. Furthermore, quantification of blood Tregs may be a suitable tool to identify those recipients who are candidates for reducing immunosuppression.

[Microscopic polyangiitis in a patient with rheumatoid arthritis]. / Poliangeítis microscópica en paciente con artritis reumatoide.

Rheumatoid arthritis (RA) is a systemic disorder that primary involves joints, although renal disease has also been associated it is not common that rapidly progressive glomerulonephritis (RPGN) appears. We report the case of a patient with nodular and aggressive RA who had an acut renal failure secondary to ANCA positive RPGN due to a Microscopic polyangiitis who was not responsive to steroids and cyclophosphamide therapy.

Similar impact of slow and delayed graft function on renal allograft outcome and function.

Kidney transplant patients can be divided into three groups, according to the initial graft function. First-week dialyzed patients form the delayed graft function (DGF) group. Nondialyzed patients are divided into slow graft function (SGF) or immediate graft function (IGF) according to whether the day 5 serum creatinine was higher versus lower than 3 mg/dL, respectively. SGF patients showed worse graft survival, above higher incidence of acute rejection and lower renal function than IGF patients, although few reports have analyzed outcomes in these groups. We analyzed the impact of SGF on graft survival, first-year renal function, and incidence of acute rejection in 291 renal transplant patients. Creatinine was significantly worse at 12 months for SGF and DGF than for IGF patients (1.9 +/- 0.8 mg/dL, 1.8 +/- 0.7 mg/dL, 1.5 +/- 0.5 mg/dL, respectively; P < .05). There was no difference in first-year renal function between SGF and DGF. The acute rejection rate was higher among the SGF than the IGF group (45% vs 21%, P < .05), but not different from DGF patients (42%, P < .05). Graft survival was better among IGF than SGF or DGF patients, with no significant difference between the last two groups (3-year graft survival, 82%, 71%, 70%, respectively; log-rank test, P < .05). Kidney transplant recipients who develop SGF have a worse outcome than patients with IGF, similar to DGF patients. SGF patients show worse graft survival, worse renal function, and higher acute rejection rates than IGF patients, despite not needing dialysis.

High initial blood levels of tacrolimus in overweight renal transplant recipients.

For the purpose of both efficacy and safety, exposure to tacrolimus and other immunosuppressive drugs must be monitored, since initial levels influence the development of acute rejection episodes, nephrotoxicity, and posttransplantation diabetes mellitus. The aim of this study was to identify risk factors for developing high initial tacrolimus blood levels. We analyzed clinical and biochemical parameters of 85 renal transplant recipients receiving tacrolimus-based immunosuppressive therapy by stratifying into subgroups of patients who displayed first tacrolimus concentrations higher and lower than 15 ng/mL. Patients with a first level of tacrolimus higher than 15 ng/mL were older (52 +/- 13 vs 40 +/- 12 years, P < .05) and had a larger body mass index (27 +/- 4 vs 23 +/- 3 kg/m2, P < .05) than patients with lower levels, despite receiving a lower weight-adjusted cumulative steroid dose (8.2 +/- 2.2 vs 9.3 +/- 2.5 mg/kg, P < .05). Upon logistic regression, age (RR 1.047, 95% CI 1.007 to 1.08, P = .021) and body mass index (RR 1.176, 95% CI 1.009 to 1.371, P = .036) remained significant risk factors for high initial blood levels of tacrolimus. As these subgroups of patients are most prone to develop posttransplantation glycemic disorders, attention must be paid to avoid high tacrolimus blood levels by diminishing initial tacrolimus doses or estimating them from ideal body weight.

Markers of fibrosis in early biopsies of renal transplants.

Many factors are involved in the development of chronic allograft nephropathy (CAN). Extracellular matrix turnover depends on the balance between fibrogenic and antifibrogenic cytokines. The aim of our study was to analyze the presence of transforming growth factor beta-1 (TGF-beta1), matrix metalloproteinase-2 (MMP-2), and mast cells in 53 early transplant biopsies using immunochemistry with specific monoclonal antibodies. We divided the patients into two groups depending on graft evolution (lost due to CAN versus functioning), renal function, presence of proteinuria, and graft survival. There were no differences in the demographic or immunological data. Renal function was worse and proteinuria greater among the group with CAN. The presence of mast cells was similar in both groups, but TGF-beta1 was expressed more and MMP-2 less in the CAN group. We observed a negative correlation between donor age and mast cells, and a positive correlation between TGF-beta1 and MMP-2. Grafts from younger donors showed better renal function, less proteinuria, greater graft survival, and less frequent development of CAN. According to our experience, cytokines involved in matrix turnover are expressed in early stages, correlating with donor age. The expressions of TGF-beta1 and MMP-2 seem to be important for the development of fibrosis in CAN.