Regression and progression of microalbuminuria in adolescents with childhood onset diabetes mellitus

Transient albuminuria in the setting of short-term severe hyperglycemia in type 1 diabetes

In a cohort of 1817 children with type 1 diabetes (T1D), short-term hyperglycemia was associated with transient albuminuria (11 % during new-onset T1D without diabetic ketoacidosis (DKA), 12 % during/after DKA, 6 % during routine screening). Our findings have implications regarding future risk of diabetic kidney disease and further investigation is needed.

Urinary N-acetyl-β-d-glucosaminidase-creatine ratio is a valuable predictor for advanced diabetic kidney disease

BACKGROUND

Many biomarkers show high diagnostic values for diabetic kidney disease (DKD), but fewer studies focus on the predictive assessment of DKD progression by blood and urinary biomarkers.

AIM

This study aims to find powerful risk predictors and identifying biomarkers in blood and urine for DKD progression.

METHODS

A total of 117 patients with type 2 DKD including early and advanced stages and their laboratory parameters were statistically assessed. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the significance of discriminating between early and advanced DKD, and the predictive power for advanced DKD was analyzed by regression analysis and trisector grouping.

RESULTS

N-acetyl-β-d-glucosaminidase-creatine (NAG/CR) level in advanced DKD was statistically higher than that in early DKD (p < 0.05), and there was a higher incidence of advanced DKD (72% vs. 56%) and high odds ratio (OR: 3.917, 95% CI: 1.579-10.011) of NAG/CR with ≥2.79 U/mmol compared with <2.79 U/mmol (p < 0.05). NAG/CR ratio also showed a higher area under the ROC curve of 0.727 (95% CI: 0.616-0.828, p = 0.010) with a high sensitivity (0.75) and a moderate specificity (0.66) when 1.93 U/mmol was set as the optimal cutoff value. The adjusted-multivariable analysis revealed that NAG/CR had an OR of 1.021 (95% CI: 1.024-1.038) and 2.223 (95% CI: 1.231-4.463) based on a continuous and categorical variable, respectively, for risk of advanced DKD. Moreover, the prevalence of advanced DKD exhibited an increasing tendency by an increment of the trisector of NAG/CR.

CONCLUSIONS

This study suggests that NAG/CR ratio is an independent predictor for advanced DKD, and it also can be used as a powerful identifying marker between early and advanced DKD.

Youth versus adult-onset type 2 diabetic kidney disease: Insights into currently known structural differences and the potential underlying mechanisms

Type 2 diabetes (T2D) is a global health pandemic with significant humanitarian, economic, and societal implications, particularly for youth and young adults who are experiencing an exponential rise in incident disease. Youth-onset T2D has a more aggressive phenotype than adult-onset T2D, and this translates to important differences in rates of progression of diabetic kidney disease (DKD). We hypothesize that youth-onset DKD due to T2D may exhibit morphometric, metabolic, and molecular characteristics that are distinct from adult-onset T2D and develop secondary to inherent differences in renal energy expenditure and substrate metabolism, resulting in a central metabolic imbalance. Kidney structural changes that are evident at the onset of puberty also serve to exacerbate the organ’s baseline high rates of energy expenditure. Additionally, the physiologic state of insulin resistance seen during puberty increases the risk for kidney disease and is exacerbated by both concurrent diabetes and obesity. A metabolic mismatch in renal energetics may represent a novel target for pharmacologic intervention, both for prevention and treatment of DKD. Further investigation into the underlying molecular mechanisms resulting in DKD in youth-onset T2D using metabolomics and RNA sequencing of kidney tissue obtained at biopsy is necessary to expand our understanding of early DKD and potential targets for therapeutic intervention. Furthermore, large-scale clinical trials evaluating the duration of kidney protective effects of pharmacologic interventions that target a metabolic mismatch in kidney energy expenditure are needed to help mitigate the risk of DKD in youth-onset T2D.

Stratification of diabetic kidney diseases via data-independent acquisition proteomics-based analysis of human kidney tissue specimens

AIM

The aims of this study were to analyze the proteomic differences in renal tissues from patients with diabetes mellitus (DM) and diabetic kidney disease (DKD) and to select sensitive biomarkers for early identification of DKD progression.

METHODS

Pressure cycling technology-pulse data-independent acquisition mass spectrometry was employed to investigate protein alterations in 36 formalin-fixed paraffin-embedded specimens. Then, bioinformatics analysis was performed to identify important signaling pathways and key molecules. Finally, the target proteins were validated in 60 blood and 30 urine samples.

RESULTS

A total of 52 up- and 311 down-regulated differential proteins were identified as differing among the advanced DKD samples, early DKD samples, and DM controls (adjusted p<0.05). These differentially expressed proteins were mainly involved in ion transport, apoptosis regulation, and the inflammatory response. UniProt database analysis showed that these proteins were mostly enriched in signaling pathways related to metabolism, apoptosis, and inflammation. NBR1 was significantly up-regulated in both early and advanced DKD, with fold changes (FCs) of 175 and 184, respectively (both p<0.01). In addition, VPS37A and ATG4B were significantly down-regulated with DKD progression, with FCs of 0.140 and 0.088, respectively, in advanced DKD and 0.533 and 0.192, respectively, in early DKD compared with the DM control group (both p<0.01). Bioinformatics analysis showed that NBR1, VPS37A, and ATG4B are closely related to autophagy. We also found that serum levels of the three proteins and urine levels of NBR1 decreased with disease progression. Moreover, there was a significant difference in serum VPS37A and ATG4B levels between patients with early and advanced DKD (both p<0.05). The immunohistochemistry assaay exhibited that the three proteins were expressed in renal tubular cells, and NBR1 was also expressed in the cystic wall of renal glomeruli.

CONCLUSION

The increase in NBR1 expression and the decrease in ATG4B and VPS37 expression in renal tissue are closely related to inhibition of the autophagy pathway, which may contribute to DKD development or progression. These three proteins may serve as sensitive serum biomarkers for early identification of DKD progression.

Prevalence of Hypertension and Albuminuria in Pediatric Type 2 Diabetes: A Systematic Review and Meta-analysis

Importance

Hypertension and albuminuria are markers of diabetes-related nephropathy and important factors associated with kidney outcomes in pediatric type 2 diabetes. However, their prevalence in these patients is unknown.

Objective

To measure the prevalence of hypertension and albuminuria in pediatric patients with type 2 diabetes and to evaluate the association of sex and race/ethnicity with these conditions.

Data Sources

MEDLINE, Embase, CINAHL, Cochrane Library, Web of Science, the gray literature, and references of the screened articles were searched for human studies from date of database inception to February 20, 2020.

Study Selection

Observational studies with at least 10 participants reporting the prevalence of hypertension and/or albuminuria in pediatric patients with type 2 diabetes were included. Three teams of 2 independent reviewers screened 7614 papers, of which 60 fulfilled the eligibility criteria.

Data Extraction and Synthesis

Three teams of 2 independent reviewers performed data extraction, risk of bias analysis, and level of evidence analyses. The meta-analysis was conducted using a random-effects model and followed the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines.

Main Outcomes and Measures

The primary outcomes included the pooled prevalence rates (percentages with 95% CI) for hypertension and albuminuria. The secondary outcomes assessed pooled prevalence rates by sex and racial/ethnic group.

Results

Sixty studies were included in the systematic review. Diabetes duration varied from inclusion at diagnosis to 15.0 years after diagnosis, and the reported mean age at diagnosis ranged from 6.5 to 21.0 years. Hypertension prevalence among 3463 participants was 25.33% (95% CI, 19.57%-31.53%). Male participants had higher hypertension risk than female participants (odds ratio [OR], 1.42 [95% CI, 1.10-1.83]), with Pacific Islander and Indigenous youth having the highest prevalence of all racial/ethnic groups (Pacific Islander youth: 26.71% [95% CI, 14.54%-40.72%]; Indigenous youth: 26.48% [95% CI, 17.34%-36.74%]; White youth: 20.95% [95% CI, 12.65%-30.57%]; African American youth: 19.04% [95% CI, 12.01%-27.23%]; Hispanic/Latino youth: 15.11% [95% CI, 6.56%-26.30%]; Asian youth: 18.37% [95% CI, 9.49%-29.23%]). Albuminuria prevalence among 2250 participants was 22.17% (95% CI, 17.34%-27.38%). Pacific Islander youth, Indigenous youth, and Asian youth had higher prevalence rates than White youth (Pacific Islander youth: 31.84% [95% CI, 11.90%-55.47%]; Indigenous youth: 24.27% [95% CI, 14.39%-35.73%]; Asian youth: 23.00% [95% CI, 18.85%-27.41%]; White youth: 12.59% [95% CI, 7.75%-18.33%]), with no sex differences (OR for male vs female participants, 0.68 [95% CI, 0.46-1.01]). Heterogeneity was high among studies, with a low to moderate risk of bias.

Conclusions and Relevance

In this study, markers of diabetes-related nephropathy were commonly detected in pediatric patients with type 2 diabetes, with a disproportionate burden noted among Pacific Islander and Indigenous youth. Personalized management strategies to target kidney outcomes are urgently needed in pediatric patients with type 2 diabetes to alleviate the burden of this condition on the kidneys.

Utility of albumin to creatinine ratio in screening for microalbuminuria among newly diagnosed diabetic patients in Uganda: a cross sectional study

Background

The aim of this study was to determine the prevalence and factors associated with microalbuminuria among newly diagnosed diabetic patients in Mulago National Referral Hospital, Uganda.

Methods

In this cross-sectional study conducted between June 2014 and January 2015, we collected information on patients' socio-demographics, biophysical profile, blood pressure, biochemical testing and echocardiographic findings using a pre-tested questionnaire. Bivariate and multivariate logistic regression analyses were used to investigate the association of several factors with microalbuminuria.

Results

Of the 175 patients recruited, males were 90(51.4%) and the mean age was 46±15 years. Majority of patients had type 2 DM 140 (80.0%) and the rest had type 1 DM 35 (20.0%). Mean glycated hemoglobin (HbA1C) was 13.9±5.3%. Mean duration of diabetes was 2 months. Prevalence of microalbuminuria was 47.4 % (95% CI: 40.0%-54.9%) overall. Pregnancy was associated with microalbuminuria (OR7.74[95%CI.1.01–76.47] P=0.050) while mild and moderate physical activity at work were inversely associated with microalbuminuria respectively (OR0.08[95%CI0.01–0.95] P=0.046) and (OR0.07[95%CI0.01–0.77] P=0.030).

Conclusion

Prevalence of microalbuminuria was high in this group. Physical activity at work may be protective against microalbuminuria and this calls for longitudinal studies. Early detection and management of microalbuminuria in diabetics may slow progression to overt diabetic nephropathy (DN).

Early renal damage among children living in the region of highest burden of chronic kidney disease of unknown etiology (CKDu) in Sri Lanka

Background

Chronic kidney disease of unknown origin (CKDu) in Sri Lanka is grouped with several other epidemics of similar nature across the world as Chronic Interstitial Nephritis in Agricultural Communities (CINAC). In CKDu endemic countries, the focus has mainly been on adults. We hypothesized that studying distribution and factors associated with elevated urine albumin to creatinine ratio (UACR), an early marker of kidney injury, among children living in a CKDu endemic area may provide important clues about the onset and progression of the disease.

Methods

This cross sectional study was performed in rural primary schools in North Central Province of Sri Lnaka, a CKDu high endemic region. Total of 2880 students aging 5 to 11 years from 67 schools were enrolled for urinalysis in a random spot urine sample. Bedside Schwartz formula was used to measure estimated glomerular filtration rate (eGFR) on all children with UACR > 30 mg/g in Polonnaruwa district and a group of age matched controls. A standard multiple linear regression using log transformed UACR as the dependent variable was performed. Mean eGFR were compared between UACR elevated group and controls using independent sample t test.

Results

Median UACR was 10.3 mg/g. Sex, ethnicity, history of having a chronic disease and age uniquely contributed to the multiple regression model which only explained 2.8% of the variance in the log of the UACR (p < 0.001). Only 15 (0.5%) had UACR> 300 mg/g while 8.2% (n = 236) had UACR between 30 to 300 mg/g and 89.8% (n = 203) of them did not have a chronic disease (Chi square 2.21, p = 0.091). Mean eGFR was significantly lower in the group with elevated UACR (88.9 mg/dl/1.73 m2, 95% CI for mean 86.4- 91.3) compared to group with normal UACR (93.7 mg/dl/1.73 m2,95% CI 91.1- 96.3) (t 2.7, p 0.007). Three out of the four students with eGFR less than 60 mg/dl/1.73 m2 had moderately elevated UACR.

Conclusion

This study provides evidence to suggest that children in CKDu endemic regions are having an early renal damage. This observation needs to be investigated further in order to understand the worldwide epidemic of CKDu.

Diffusion tensor imaging MRI of sickle cell kidney disease: initial results and comparison with iron deposition

Chronic kidney disease (CKD) occurs in over one-third of patients with sickle cell disease (SCD) and can progress to end-stage renal disease. Unfortunately, current clinical assessments of kidney function are insensitive to early-stage CKD. Previous studies have shown that diffusion magnetic resonance imaging (MRI) can sensitively detect regional renal microstructural changes associated with early-stage CKD. However, previous MRI studies in patients with SCD have been largely limited to the detection of renal iron deposition assessed by T₂ * relaxometry. In this pilot imaging study, we compare MRI assessments of renal microstructure (diffusion) and iron deposition (T₂ *) in patients with SCD and in non-SCD control subjects. Diffusion tensor imaging (DTI) and T₂ * relaxometry MRI data were obtained for pediatric (n = 5) and adult (n = 4) patients with SCD, as well as for non-SCD control subjects (n = 10), on a Siemens Espree 1.5-T MRI scanner. A region-of-interest analysis was used to calculate mean medullary and cortical values for each MRI metric. MRI findings were also compared with clinical assessments of renal function and hemolysis. Patients with SCD showed a significant decrease in medullary fractional anisotropy (FA, p = 0.0001) in comparison with non-SCD subjects, indicative of microstructural alterations in the renal medulla of patients with SCD. Cortical and medullary reductions in T₂ * (increased iron deposition, p = ≤0.0001) were also observed. Significant correlations were also observed between kidney T₂ * assessments and multiple measures of hemolysis. This is the first DTI MRI study of patients with SCD to demonstrate reductions in medullary FA despite no overt CKD [estimated glomerular filtration rate (eGFR) > 100 mL/min/1.73 m² ]. These medullary FA changes are consistent with previous studies in patients with CKD, and suggest that DTI MRI can provide a useful measure of kidney injury to complement MRI assessments of iron deposition.

Microalbuminuria among Newly Diagnosed Diabetic Patients at Mulago National Referral Hospital in Uganda: A Cross Sectional Study

Background

Microalbuminuria is an early marker of nephropathy, cardiovascular diseases and severe ocular morbidity in adults with diabetes mellitus. This subclinical condition is associated with high morbidity and mortality. Microalbuminuria precedes the development of overt diabetic nephropathy by 10-14 years. At this stage, one can reverse diabetic nephropathy or prevent its progression. Unfortunately, tests to detect microalbuminuria in diabetics are not routinely done in Uganda. This study sought to determine the prevalence and factors associated with microalbuminuria among newly diagnosed diabetic patients in the National Referral Hospital in Uganda.

Methods

In this cross-sectional study conducted between June 2014 and January 2015, we recruited 175 newly diagnosed adult diabetic patients. Information on patients' socio-demographics, biophysical profile, blood pressure measurement, biochemical testing and echocardiographic findings was obtained for all the participants using a pre-tested questionnaire. Microalbuminuria was defined as Albumin to Creatinine Ratio (ACR) between 30 and 299 mg/g. Bivariate and multivariate logistic regression analyses were used to investigate the association of several factors with microalbuminuria.

Results

Of the 175 patients recruited, males were 90 (51.4%) and the mean age was 46 ± 15 years. Majority of patients had type 2 DM 140 (80.0%) and the rest had type 1 DM 35 (20.0%). The mean HbA1C was 13.9 ± 5.3%. Mean duration of diabetes was 2 months. Prevalence of microalbuminuria was 47.4% (95% CI: 40.0%-54.9%) among all the patients that were assessed in the study. The independent factor associated with microalbuminuria was pregnancy (OR7.74[95% CI: 1.01-76.47] P = 0.050) while mild and moderate physical activity at work were inversely associated with microalbuminuria respectively (OR0.08[95% CI: 0.01-0.95] P = 0.046) and (OR0.07[95% CI: 0.01-0.77] P = 0.030).

Conclusions

Prevalence of microalbuminuria was high in this patient population of newly diagnosed diabetes mellitus. Pregnancy was positively associated with significant microalbuminuria while physical activity at work was inversely associated with microalbuminuria. Early detection and management of microalbuminuria in asymptomatic individuals may help in preventing deterioration in renal function and development of overt diabetic nephropathy and progression to ESRD.

Insights into Diabetic Kidney Disease Using Urinary Proteomics and Bioinformatics

A number of proteomic and peptidomic analyses of urine from diabetic subjects have been published in the quest for a biomarker that predicts progression of nephropathy. Less attention has been paid to the relationships between urinary proteins and the underlying biological processes revealed by the analyses. In this review, we focus on the biological processes identified by studying urinary proteins and protein-protein interactions at each stage of diabetic nephropathy to provide an overview of the events underlying progression of kidney disease reflected in the urine. In uncomplicated diabetes, proteomic/peptidomic analyses indicate that early activation of fibrotic pathways in the kidney occurs before the onset of microalbuminuria. In incipient nephropathy, when albumin excretion rates are abnormal, proteomic/peptidomic analyses suggest that changes in glomerular permselectivity and tubular reabsorption account, at least in part, for the proteins and peptides that appear in the urine. Finally, overt nephropathy is characterized by proteins involved in wound healing, ongoing fibrosis, and inflammation. These findings suggest that there is a spectrum of biological processes in the diabetic kidney and that assessing protein networks may be more informative than individual markers with respect to the stage of disease and the risk of progression.

Prevalence of Diabetes and Diabetic Nephropathy in a Large U.S. Commercially Insured Pediatric Population, 2002-2013

OBJECTIVE

To estimate the prevalence of diabetes and diabetic nephropathy in a large population of U.S. commercially insured patients aged <18 years from 2002 to 2013.

RESEARCH DESIGN AND METHODS

Using the U.S. MarketScan Commercial Claims and Encounters Database, we identified 96,171 pediatric patients with diabetes and 3,161 pediatric patients with diabetic nephropathy during 2002-2013. We estimated prevalence of pediatric diabetes overall, by diabetes type, age, and sex, and prevalence of pediatric diabetic nephropathy overall, by age, sex, and diabetes type.

RESULTS

The annual prevalence of diabetes in the whole pediatric population increased from 1.86 to 2.82 per 1,000 during 2002-2013: 1.48 to 2.32 per 1,000 for type 1 diabetes and 0.38 to 0.67 per 1,000 for type 2 diabetes in 2002-2006 and then 0.56 to 0.49 per 1,000 thereafter. The annual prevalence of diabetic nephropathy in pediatric patients with diabetes increased from 1.16 to 3.44% for all cases and 0.83 to 2.32% for probable cases only in 2002-2013. Prevalence of diabetes and diabetic nephropathy was highest in patients aged 12 to <18 years. While prevalence of type 1 diabetes was higher in male than in female youth, prevalence of type 2 diabetes and diabetic nephropathy was higher in female than in male youth. There was no difference in prevalence of diabetic nephropathy by diabetes type.

CONCLUSIONS

The prevalence of diabetes and diabetic nephropathy increased in the U.S. MarketScan commercially insured pediatric population from 2002 to 2013. The prevalence of diabetes and diabetic nephropathy markedly increased starting at age 12 years.