Domingo Marrero

Early association of low-grade albuminuria and allograft dysfunction predicts renal transplant outcomes.

Background. Data on the combined associations of albuminuria and estimated glomerular filtration rate (eGFR) with renal transplant outcomes are limited. Our objective was to explore how renal transplant outcomes could be predicted by a combined variable of early low-grade albuminuria and allograft dysfunction. Methods. We studied a cohort of adult deceased-donor kidney transplant recipients who were subdivided into four groups according to median albuminuria (100 mg/day, interquartile range, 0–470 mg/day) and median eGFR (60 mL/min/1.73 m2; interquartile range, 30–73 mL/min/1.73 m2) at third month posttransplantation as follows: group I (albuminuria <100 and eGFR >60, n=238); group II (albuminuria ≥100 and eGFR >60, n=151); group III (albuminuria <100 and eGFR ⩽60; n=167); and group IV (albuminuria ≥100 and eGFR ⩽60, n=228). Results. Death-censored graft survival was significantly lower in group IV compared with the rest (P<0.0001). Multivariate Cox regression analysis using fixed and time-dependent covariates showed that the combination of low-grade albuminuria and lower eGFR was associated with graft failure (hazard ratio, 2.2, 95% confidence interval, 1.3–3.7; P=0.003). Likewise, but to a lesser extent, the risk of mortality was increased for group IV (hazard ratio, 1.7, 95% confidence interval, 1.01–2.8; P=0.042). Conclusions. Early association of low-grade albuminuria and allograft dysfunction represents an important risk factor of graft failure and mortality. This additive effect should be considered to identify individuals at risk for adverse kidney transplantation outcomes.

Impact of cold ischemia time on renal allograft outcome using kidneys from young donors

Prolonged cold ischemia time (CIT) is associated with delayed graft function and worse kidney transplant (KT) outcome, but the effect of CIT on long‐term allograft survival in KT from younger donors has not been well established. We investigated the predictive value of CIT exposure on long‐term death‐censored graft loss in 829 KT recipients from younger donors (<50 years) that were performed in our center between 1991 and 2005. Overall death‐censored graft failure rate was significantly higher in CIT≥19 h group versus CIT<19 h group (26 vs. 16.5%; P = 0.002). Significant differences were also observed when patients with primary nonfunctioning graft were excluded (21 vs. 14%; P = 0.020) and in patients who received tacrolimus plus mycophenolate mofetil (12 vs. 4%; P = 0.05). By multivariate Cox analysis, CIT was found to be independently associated with death‐censored graft loss with a 20% increase for every 5 h of CIT [relative risk (RR) 1.04; 95% Confidence Interval (CI): 1.01–1.1; P = 0.021]. Likewise, graft loss risk significantly increased in CIT≥19 h group versus CIT<19 h group (RR 1.5; 95%CI: 1.1–2.1; P = 0.023). Prolonged CIT is an independent predictor of graft survival in KT from younger donors. Efforts at minimizing CIT (<19 h) should improve transplant outcome significantly in this population.

Carotid atheromatosis in nondiabetic renal transplant recipients: the role of prediabetic glucose homeostasis alterations.

Background. Prediabetic glucose homeostasis alterations are important cardiovascular risk factors but their role in renal transplant recipients (RTR) has not been established. Methods. In 172 RTRs without pretransplant or de novo diabetes, we measured carotid intima media thickness (c-IMT) and performed an oral glucose tolerance test (OGTT). Results. In multivariate analysis, age, hypertension and male sex were independently associated with a c-IMT in the third tertile. A significant interaction between gender and glucose homeostasis parameters was observed. Among male RTR, those with a c-IMT in the third tertile showed significantly higher plasma glucose and HbA1c levels (5±0.5% vs. 5.1±0.5% vs. 5.5±0.4%; P<0.01 tertile 3 vs. 2 or 1) than those in other tertiles. Insulin action parameters were not significantly different. The odds ratio of being in the higher c-IMT tertile was 2.9 (95% CI: 1.05–8.1) per each 1% increase of HbA1c. By contrast, glucose and HbA1c levels were not significantly different between c-IMT tertiles in female RTR. However, age-adjusted insulin levels after OGTT were higher (86±10 vs. 51.7±9.4; P=0.02) and the insulin sensitivity index lower (0.8±0.3 vs. 0.048±0.03; P=0.04) among females in the third tertile as compared to the first one. Conclusion. Prediabetic glucose homeostasis alterations in RTRs are related to carotid atherosclerosis, although there may be gender differences in the underlying alteration.

Does the difference in donor and recipient weight influence renal graft survival

INTRODUCTION Grafts from older donors or those in recipients with a greater body mass index (BMI) as compared with the donor may develop hyperfiltration syndrome that shortens renal graft survival. OBJECTIVES To assess whether the differences in weight and BMI between donor and recipient correlated with renal function, proteinuria, or graft survival among recipients of grafts from expanded criteria donors. MATERIALS AND METHODS We undertook a prospective, observational study in 180 recipients of grafts from expanded criteria donors performed between 1999 and 2006. All grafts had been biopsied previously for viability. The recipients underwent immunosuppression with basiliximab, late introduction of tacrolimus, mycophenolate mofetil and steroids. The study population was divided into three groups, depending on the tertile of the donor-to-recipient weight ratio (<1, n=64; 1-1.2, n=56; >1.2, n=60), and the donor-to-recipient BMI ratio (<0.97, n=59; 0.97-1.13, n=60; >1.13, n=60). The glomerular filtration rate was estimated from the modified diet in renal disease (MDRD) equation. RESULTS The mean age of the donors was 63.54 years and of the recipients, 58.38 years. The proportion of male-to-female donors was 52:48 and recipients 57.8:42.2 (P=NS). No significant differences in overall graft survival were observed between the tertiles. There was a negative correlation between the donor-to-recipient weight ratio and serum creatinine value at 1 (P<.001), 3 (P=.013), and 12 months (P=.005) after transplantation, and a positive correlation with the MDRD at 1 month (P<.001). No relation was noted between weight and proteinuria at 1 (P=.25), 3 (P=.51), or 12 months (P=.90). The results were similar after analyzing the ratio of the BMI to creatinine, MDRD or proteinuria, as well as in cases of a female donor to a male recipient. CONCLUSIONS Differences in weights between the donor and the recipient did not appear to affect graft survival or proteinuria among patients receiving grafts from expanded criteria donors, though it may be related to renal function during the early posttransplant stages.