Changes in Numbers of Glomerular Macrophages Between Two Consecutive Biopsies and the Association With Renal Transplant Graft Survival.

BACKGROUND: Macrophages are involved in kidney transplants. The aim of the study was to investigate if changes exist in the levels of glomerular macrophage index (GMI) between two consecutive kidney transplant biopsies, and if so to determine their potential impact on graft survival. METHODS: Two consecutive biopsies were performed on the same renal graft in 623 patients. GMI was categorized into three GMI classes: ≤1.8 Low, 1.9-4.5 Medium, and ≥4.6 High. This division yielded nine possible switches between the first and second biopsies (Low-Low, Low-Medium, etc.). Cox-regressions were used and hazard ratios (HR) with 95% confidence interval (CI) are presented. RESULTS: The worst graft survival was observed in the High-High group, and the best graft survival was observed in the Low-Low and High-Low groups. Compared to the High-High group, a reduction of risk was observed in nearly all other decreasing groups (reductions between 65% and 80% of graft loss). After adjustment for covariates, the risk for graft-loss was lower in the Low-Low (HR = 0.24, CI 0.13-0.46), Low-Medium (HR = 0.25, CI 0.11-0.55), Medium-Low (HR = 0.29, CI 0.11-0.77), and the High-Low GMI (HR = 0.31, CI 0.10-0.98) groups compared to the High-High group as the reference. CONCLUSIONS: GMI may change dynamically, and the latest finding is of most prognostic importance. GMI should be considered in all evaluations of biopsy findings since high or increasing GMI levels are associated with shorter graft survival. Future studies need to consider therapeutic strategies to lower or maintain a low GMI. A high GMI besides a vague histological finding should be considered as a warning sign requiring more frequent clinical follow up.

Sex-specific time trends of long-term graft survival after kidney transplantation - a registry-based study.

BACKGROUND: Sex-specific trends over time with respect to kidney graft survival have scarcely been described in earlier studies. The present study aimed to examine whether kidney graft survival differs between women and men over time. METHODS: This study was based on prospectively collected data extracted from a quality registry including all kidney transplant patients between January 1965 and September 2017 at the transplantation center of a university hospital in Sweden. The transplantation center serves a population of approximately 3.5 million inhabitants. Only the first graft for each patient was included in the study resulting in 4698 transplantations from unique patients (37% women, 63% men). Patients were followed-up until graft failure, death, or the end of the study. Death-censored graft survival analysis after kidney transplantation (KT) was performed using Kaplan-Meier analysis with log-rank test, and analysis adjusted for confounders was performed using multivariable Cox regression analysis. RESULTS: Median age at transplantation was 48 years (quartiles 36-57 years) and was similar for women and men. Graft survival was analyzed separately in four transplantation periods that represented various immunosuppressive regimes (1965-1985, 1986-1995, 1996-2005, and 2006-2017). Sex differences in graft survival varied over time (sex-by-period interaction, p = 0.026). During the three first periods, there were no significant sex differences in graft survival. However, during the last period, women had shorter graft survival (p = 0.022, hazard ratio (HR) 1.71, 95% confidence interval (CI) 1.1-2.7, adjusted for covariates). Biopsy-proven rejections were more common in women. CONCLUSIONS: In this registry-based study, women had shorter graft survival than men during the last observation period (years 2006-2017).

Risk factors for biopsy complications in initial versus subsequent biopsies in native and transplant kidneys.

BACKGROUND: Few studies exist about risk factors for complications in subsequent biopsies. PURPOSE: To explore risk factors for complications in initial versus subsequent biopsies in native and transplant kidneys, which may predict biopsy complications. MATERIAL AND METHODS: In a multicenter study, 2830 native kidney biopsies (4.3% subsequent) were analyzed for major complications (1251 of these were also analyzed for minor) and 667 transplant kidney biopsies (29% subsequent) were analyzed for major and minor complications. No death or nephrectomy were described. Fisher's exact test, Student's t-test, chi-square analyses, and univariate and multiple binary logistic regression analyses were employed; P < 0.05 was considered significant. RESULTS: In initial native kidney biopsies, the frequency of major complications was higher in women compared to men (odds ratio 1.6, 95% confidence interval 1.1-2.2), in younger patients (50 vs. 54 years, P = 0.007), and in patients with lower weight (78 vs. 82 kg, P = 0.005). In subsequent native kidney biopsies, patients with major complications had a higher systolic blood pressure (145 vs. 132 mmHg, P = 0.03). In initial transplant kidney biopsies, biopsies with major complications had less glomeruli in the biopsy (17 vs. 24, P = 0.046). In subsequent transplant kidney biopsies, patients with major complications had a higher mean arterial pressure (112 vs. 98 mmHg, P = 0.002). In subsequent native kidney biopsies, there was a higher number of SLE-nephritis (12% vs. 4.6%, P = 0.001) compared to initial biopsies. CONCLUSION: The different types of risk factors for complications in initial versus subsequent renal biopsies could be important for the clinicians to improve patients' safety.

Melanotan II: a possible cause of renal infarction: review of the literature and case report.

Renal infarction is an uncommon condition resulting from an acute disruption of renal blood flow and it is potentially life-threatening disease. The cause and outcome of renal infarction is not well established and is frequently misdiagnosed or diagnosed late. Melanotan II is a non-selective melanocortin-receptor agonist and its effect on humans is an increasing of skin pigmentation, producing of spontaneous penile erection and sexual stimulation. Melanotan II inducing rhabdomyolysis and renal failure have been described previously. We present a review of Melanotan II and the possible effects of this drug on the kidneys by including a case of a renal infarction most likely attributed to Melanotan II. In the mechanism of renal injury with Melanotan II, thrombotic pharmacological influence and possible direct toxic effect on renal parenchyma must be considered.

Decreased systolic blood pressure is associated with increased risk of all-cause mortality in patients with type 2 diabetes and renal impairment: A nationwide longitudinal observational study of 27,732 patients based on the Swedish National Diabetes Register.

BACKGROUND: Previous studies have shown a U-shaped relationship between systolic blood pressure and risk of all-cause of mortality in patients with type 2 diabetes and renal impairment. AIMS: To evaluate the associations between time-updated systolic blood pressure and time-updated change in systolic blood pressure during the follow-up period and risk of all-cause mortality in patients with type 2 diabetes and renal impairment. PATIENTS AND METHODS: A total of 27,732 patients with type 2 diabetes and renal impairment in the Swedish National Diabetes Register were followed for 4.7 years. Time-dependent Cox models were used to estimate risk of all-cause mortality. Time-updated mean systolic blood pressure is the average of the baseline and the reported post-baseline systolic blood pressures. RESULTS: A time-updated systolic blood pressure < 130 mmHg was associated with a higher risk of all-cause mortality in patients both with and without a history of chronic heart failure (hazard ratio: 1.25, 95% confidence interval: 1.13-1.40 and hazard ratio: 1.26, 1.17-1.36, respectively). A time-updated decrease in systolic blood pressure > 10 mmHg between the last two observations was associated with higher risk of all-cause mortality (-10 to -25 mmHg; hazard ratio: 1.24, 95% confidence interval: 1.17-1.32). CONCLUSION: Both low systolic blood pressure and a decrease in systolic blood pressure during the follow-up are associated with a higher risk of all-cause mortality in patients with type 2 diabetes and renal impairment.

Risk factors for the development of albuminuria and renal impairment in type 2 diabetes--the Swedish National Diabetes Register (NDR).

BACKGROUND: The aim of this study was to identify clinical risk factors associated with the development of albuminuria and renal impairment in patients with type 2 diabetes (T2D). In addition, we evaluated if different equations to estimate renal function had an impact on interpretation of data. This was done in a nationwide population-based study using data from the Swedish National Diabetes Register. METHODS: Three thousand and six hundred sixty-seven patients with T2D aged 30-74 years with no signs of renal dysfunction at baseline (no albuminuria and eGFR >60 mL/min/1.73 m(2) according to MDRD) were followed up for 5 years (2002-2007). Renal outcomes, development of albuminuria and/or renal impairment [eGFR < 60 mL/min/1.73 m(2) by MDRD or eCrCl > 60 mL/min by Cockgroft-Gault (C-G)] were assessed at follow-up. Univariate regression analyses and stepwise regression models were used to identify significant clinical risk factors for renal outcomes. RESULTS: Twenty percent of patients developed albuminuria, and 11% renal impairment; thus, ~6-7% of all patients developed non-albuminuric renal impairment. Development of albuminuria or renal impairment was independently associated with high age (all P < 0.001), high systolic BP (all P < 0.02) and elevated triglycerides (all P < 0.02). Additional independent risk factors for albuminuria were high BMI (P < 0.01), high HbA1c (P < 0.001), smoking (P < 0.001), HDL (P < 0.05) and male sex (P < 0.001), and for renal impairment elevated plasma creatinine at baseline and female sex (both P < 0.001). High BMI was an independent risk factor for renal impairment when defined by MDRD (P < 0.01), but low BMI was when defined by C-G (P < 0.001). Adverse effects of BMI on HbA1c, blood pressure and lipids accounted for ~50% of the increase risk for albuminuria, and for 41% of the increased risk for renal impairment (MDRD). CONCLUSIONS: Distinct sets of risk factors were associated with the development of albuminuria and renal impairment consistent with the concept that they are not entirely linked in patients with type 2 diabetes. Obesity and serum triglycerides are semi-novel risk factors for development of renal dysfunction and BMI accounted for a substantial proportion of the increased risk. The equations used to estimate renal function (MDRD vs. C-G) had an impact on interpretation of data, especially with regard to body composition and gender.