Background: Proteinuria is associated with poor allograft and patient survival in kidney transplant recipients. However, the clinical relevance of spot urine protein-to-creatinine ratio (PCR) or albumin-to-creatinine ratio (ACR) as predictors of renal outcomes during the early postoperative period following kidney transplantation (KT) has not been determined. Methods: This single-center retrospective cohort study included 353 kidney transplant recipients who underwent KT between 2014 and 2017 and were followed up for more than 3 years. Among them, 186 and 167 recipients underwent living donor KT and deceased donor KT, respectively. The PCR and ACR were measured during the immediate postoperative period (within 7 days postoperatively), before discharge (2-3 weeks postoperatively), and 3-6 months postoperatively. Results: The median age of the patients was 51 years (interquartile range, 43-59 years), and 62.9% were male. An immediate postoperative PCR of ≥1 mg/mg was associated with old age, diabetes mellitus, high systolic blood pressure, delayed graft function, and donor factors (deceased donor KT, old age, and high serum creatinine concentrations). The PCR and ACR 3 to 6 months posttransplant were inversely associated with the estimated glomerular filtration rate at 1 year posttransplant. Deceased donor KT recipients with immediate postoperative PCR of ≥3 mg/mg showed a greater incidence of delayed graft function and lower estimated glomerular filtration rate before discharge than those with immediate postoperative PCR of <3 mg/mg. Conclusion: Early postoperative proteinuria is a useful biomarker to predict early renal outcomes after KT.

Low health-related quality of life (HRQOL) is associated with adverse outcomes in diabetic kidney disease (DKD) patients. We examined the modifiable factors associated with low HRQOL in these patients. We enrolled 141 DKD patients. HRQOL was assessed with the Short Form 36 (SF-36) questionnaire. Low HRQOL was defined as a score > one standard deviation below the mean. Depression and anxiety were assessed with the Hospital Anxiety and Depression Scale (HADS-D and HDAS-A, respectively). The patients’ median age was 65 years, and 73% were men. The prevalence rates of anxiety and depression were 8% (n = 11) and 17% (n = 24), respectively. Forty (28%) patients were identified as poor sleepers, and 40 (28%) had low physical activity levels. Anxiety, depression, and poor sleep quality were negatively correlated with SF-36 scores. Higher levels of physical activity and the estimated glomerular filtration rate (eGFR) were correlated with higher SF-36 scores, which indicated better health status. Higher depression scores (HADS-D scores) were associated with low HRQOL, independent of factors including age, sex, smoking status, comorbidities, eGFR, anemia, sleep quality, anxiety levels, and physical activity levels (odds ratio, 1.43; 95% confidence interval, 1.17–1.75). Among the clinical and psycho-physical factors, depression was a main determinant of low HRQOL in DKD patients.

Background: Serum cystatin C (cysC), which is less affected by sex, race, and muscle mass than creatinine, is a useful biomarker of the estimated glomerular filtration rate (eGFR). The standardization of cysC measurements remains controversial, although a certified reference material (ERM-DA471/IFCC) is available. Moreover, the effect of combinations of cysC reagents and equations for eGFR is unclear.Methods: We conducted a simulation analysis of cysC measured using two reagents standardized against ERM-DA471/IFCC-Gentian cystatin C immunoassay (Gentiancys; Gentian AS, Moss, Norway) and Roche Tina-quant Cystatin C Gen.2 (Rochecys; Roche, Mannheim, Germany)-on a Cobas c702 system (Roche) and eGFR generated by eight combinations of four equations: 2012 cystatin C-based Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPIcys); the Caucasian, Asian, pediatric, and adult equation (CAPAeq); full age spectrum equation (FASeq); and 2023 cystatin C-based European Kidney Function Consortium equation (EKFCcys).Results: A total of 148 participants (mean age, 60.5 ± 14.5 years; 43% female) were enrolled. The mean cysC was 1.72 ± 1.44 mg/L for Gentiancys and 1.71 ± 1.35 mg/L for Rochecys. Regression analysis showed concordance between the reagents within 0.85-4.40 mg/L when using ± 7.61% total allowable error. Lin's concordance correlation coefficient of eGFR, by combining the measuring system and equation, varied from 0.73 to 1.00. Conclusions:The equivalence of cysC values at low concentrations ( < 0.85 mg/L) between the two reagents was unsatisfactory. Results obtained with different measurement systems could lead to larger differences in eGFR varying with the combination.