Utilization of the corticomedullary difference in magnetic resonance imaging-derived apparent diffusion coefficient for noninvasive assessment of chronic kidney disease in type 2 diabetes.

BACKGROUNDS: Accumulating data demonstrated that the cortico-medullary difference in apparent diffusion coefficient (ΔADC) of diffusion-weighted magnetic resonance imaging (DWI) was a better correlation with kidney fibrosis, tubular atrophy progression, and a predictor of kidney function evolution in chronic kidney disease (CKD). OBJECTIVES: We aimed to assess the value of ΔADC in evaluating disease severity, differential diagnosis, and the prognostic risk stratification for patients with type 2 diabetes (T2D) and CKD. METHODS: Total 119 patients with T2D and CKD who underwent renal MRI were prospectively enrolled. Of them, 89 patients had performed kidney biopsy for pathological examination, including 38 patients with biopsy-proven diabetic kidney disease (DKD) and 51 patients with biopsy-proven non-diabetic kidney disease (NDKD) and Mix (DKD + NDKD). Clinicopathological characteristics were compared according to different ΔADC levels. Moreover, univariate and multivariate-linear regression analyses were performed to explore whether ΔADC was independently associated with estimated glomerular filtration rate (eGFR) and urinary albumin creatinine ratio (UACR). The diagnostic performance of ΔADC for discriminating DKD from NDKD + Mix was evaluated by receiver operating characteristic (ROC) analysis. In addition, an individual's 2- or 5-year risk probability of progressing to end-stage kidney disease (ESKD) was calculated by the kidney failure risk equation (KFRE). The effect of ΔADC on prognostic risk stratification was assessed. Additionally, net reclassification improvement (NRI) was used to evaluate the model performance. RESULTS: All enrolled patients had a median ΔADC level of 86 (IQR 28, 155) × 10-6 mm2/s. ΔADC significantly decreased across the increasing staging of CKD (P < 0.001). Moreover, those with pathological-confirmed DKD has a significantly lower level of ΔADC than those with NDKD and Mix (P < 0.001). It showed that ΔADC was independently associated with eGFR (ß = 1.058, 95% CI = [1.002,1.118], P = 0.042) and UACR (ß = -3.862, 95% CI = [-7.360, -0.365], P = 0.031) at multivariate linear regression analyses. Besides, ΔADC achieved an AUC of 0.707 (71% sensitivity and 75% specificity) and AUC of 0.823 (94% sensitivity and 67% specificity) for discriminating DKD from NDKD + Mix and higher ESKD risk categories (≥50% at 5 years; ≥10% at 2 years) from lower risk categories (<50% at 5 years; <10% at 2 years). Accordingly, the optimal cutoff value of ΔADC for higher ESKD risk categories was 66 × 10-6 mm2/s, and the group with the low-cutoff level of ΔADC group was associated with 1.232 -fold (95% CI 1.086, 1.398) likelihood of higher ESKD risk categories as compared to the high-cutoff level of ΔADC group in the fully-adjusted model. Reclassification analyses confirmed that the final adjusted model improved NRI. CONCLUSIONS: ΔADC was strongly associated with eGFR and UACR in patients with T2D and CKD. More importantly, baseline ΔADC was predictive of higher ESKD risk, independently of significant clinical confounding. Specifically, ΔADC <78 × 10-6 mm2/s and <66 × 10-6 mm2/s would help to identify T2D patients with the diagnosis of DKD and higher ESKD risk categories, respectively.

Assessment of urinary NGAL for differential diagnosis and progression of diabetic kidney disease.

OBJECTIVE: Chronic kidney disease (CKD) related to diabetes has become more common than glomerulonephritis in recent years. Given the inefficient and difficult identification of diabetic kidney disease (DKD) from non-diabetic kidney disease (NDKD) as well as a result of emerging evidence supporting a role for tubular involvement in DKD, we aimed to investigate the utility of urinary neutrophil gelatinase-associated lipocalin (uNGAL) in the differential diagnosis and predictive value of DKD from NDKD. METHODS: Data for 100 type 2 diabetic patients with CKD at our center from June 2016 to August 2019 were reviewed. All the patients were categorized into 2 groups by the renal biopsy results: DKD and NDKD. Urinary NGAL levels were normalized by urinary creatinine and calculated as uNGAL/creatinine ratios (uNCR). The independent factors of the occurrence of DKD and the diagnostic implications of uNCR were explored by logistic regression and receiver-operating characteristic (ROC) curve analysis. In addition, we analyzed the relationship between uNCR and proteinuria in patients with DKD by Pearson test and linear regression. Kaplan-Meier survival analysis was performed to assess the prospective association of uNCR with the renal outcome. RESULTS: Significantly higher levels of uNCR were observed in patients with DKD when compared to those with NDKD (28.65 ng/mg vs 27.47 ng/mg, p< .001). uNCR was identified as an independent risk factor for the occurrence of DKD in diabetic patients with CKD (odds ratio [OR] = 1.020; 95%CI = [1.001-1.399], p = .042). The optimal cutoff value of uNCR for predicting DKD was 60.685 ng/mg with high specificity (90.5%) but relatively low sensitivity (55.7%). In Pearson test, uNCR was positively correlated with proteinuria, serum creatine, blood urea nitrogen, duration of diabetes, interstitial inflammation score and global sclerosis, whereas it was inversely correlated with eGFR, hemoglobin, serum albumin and 25-hydroxy vitamin D. Furthermore, in a fully adjusted model including eGFR, serum albumin and total cholesterol, the group with uNCR>60.685 ng/mg was associated with 7.595 times higher likelihood of nephrotic-range proteinuria compared to the group with uNCR≤60.685 ng/mg. In the Kaplan-Meier survival analysis, the event-free survival probability in patients with uNCR>60.685 ng/mg was significantly lower than those with uNCR≤60.685 ng/mg (p = .048). CONCLUSIONS: uNCR might serve as a potential tool for identifying cases in which there was a high clinical suspicion of DKD and that in whom confirmatory biopsy could be considered, and the best predictive cutoff value of normalized uNCR for DKD diagnosis was 60.685 ng/mg. Type 2 diabetic patients with increased level of uNCR had higher risk to nephrotic-range proteinuria and worse renal outcome.

IPDN-China promotes the development of pediatric dialysis in China.

BACKGROUND: In mainland China, dialysis for children with end-stage renal disease (ESRD) was not introduced until the 1980s. To describe the development of pediatric dialysis in different regions of China, a national pediatric dialysis network, namely, International Pediatric Dialysis Network-China (IPDN-China) ( www.pedpd.org.cn ), was launched in 2012. METHODS: Original and updated information from the renal centers registered with the IPDN-China was collected between 2012 and 2016 from two sources, namely, the registry and the survey, and demographic features were analyzed. RESULTS: Due to promotion by the IPDN-China, the number of registered renal centers increased from 12 to 39 between 2012 and 2016, with a significant increase in the coverage of the Chinese administrative divisions (from 26.5 to 67.6%) (p < 0.01); and the coverage of the pediatric (0~14 years old) population increased to nearly 90% in 2016. The distribution of renal centers indicated that East China had the highest average number of registered centers per million population (pmp) 0~14-year-old age group. Seventeen relatively large dialysis centers were distributed across 14 divisions. Various modalities of renal replacement therapy (RRT) were available in most centers. The IPDN-China has promoted collaborations between dieticians, psychologists, and social workers on dialysis teams to provide better service to children with ESRD and their families. The proportion of centers with all three types of paramedic support (i.e., dieticians, psychologists, and social workers) as well as the proportion of centers with a partial paramedic team significantly increased between 2012 (25.0%) and 2016 (69.2%) (p < 0.05). In terms of the point prevalent cases of patients (aged < 18 years), data from the survey of 39 registered centers revealed that the number of children with ESRD who were on RRT was 578 (49% received a kidney transplant) at the end of 2016, which was more than that reported in previous surveys. Data from the registry showed that 349 dialysis patients had been enrolled as of the end of 2016. The median age at RRT start was 9.5 years, and the leading cause of ESRD was congenital abnormalities of the kidney and urinary tract (CAKUT). CONCLUSIONS: The IPDN-China has helped to promote the development of pediatric dialysis for ESRD in China by improving the organization of care for dialysis patients and increasing the availability and the quality of RRT for patients who need it. To improve knowledge about the epidemiology and outcomes of pediatric RRT around the country, a sustained effort needs to be made by the IPDN-China to increase the enrollment of dialysis patients and increase the number of registered centers in the future.

Opportunity and marginal abatement cost savings from China's pilot carbon emissions permit trading system: Simulating evidence from the industrial sectors.

China has launched pilot carbon emissions permit trading schemes (ETS) in seven regions since 2013/2014 and has established a nationwide ETS in the power industry by the end of 2017. Recent literature has evaluated China's seven pilot regions on design aspects of the ETS, and yet little is known about the potential recovery of economic output loss through introducing the ETS. This study considers the recovery of industrial value added loss and thus measures the abatement cost savings from trading to evaluate the necessity and feasibility of China's pilot ETSs. The analysis develops a parametric and nonparametric combined technique to calculate the opportunity abatement cost savings (i.e., potential abatement cost savings and unrealized abatement cost savings) and marginal abatement cost savings (i.e., changes on carbon shadow prices) in China's pilot ETSs during 2011-2015. It additionally provides an estimation of potential carbon emissions reduction from ETS. Both cross-industrial trading and intertemporal trading are considered, and three simulations, defined as no trading, cross-industrial trading, and cross-industrial and intertemporal trading, are conducted. We found that, i) 1-16% potential abatement cost savings and 2-12% unrealized abatement cost savings would be identified in China's pilot ETS regions. ii) 0.5-33% and 1.6-25% carbon emissions reduction potential would be realized respectively by introducing ETS and eliminating the operational inefficiency of the ETS. iii) Marginal abatement cost savings would both exist in almost all regions if the ETS were implemented and if the ETS were fully operational.