Spot urine albumin to creatinine ratio and serum cystatin C are effective for detection of diabetic nephropathy in childhood diabetic patients

Serum angiopoietin-2: a promising biomarker for early diabetic kidney disease in children and adolescents with type 1 diabetes

Albuminuria has been considered the golden standard biomarker for diabetic kidney disease (DKD), but appears once significant kidney damage has already occurred. Angiopoietin-2 (Angpt-2) has been implicated in the development and progression of DKD in adults. We aimed to explore the association of serum Angpt-2 levels with DKD in children and adolescents with type 1 diabetes mellitus (T1DM) of short duration (3-5 years) and to evaluate the predictive power of serum Angpt-2 in the early detection of DKD prior to the microalbuminuric phase. The current cross-sectional study included 90 children divided into three age and sex-matched groups based on urinary albumin-to-creatinine ratio (UACR): microalbuminuric diabetic group (n = 30), non-albuminuric diabetic group (n = 30), and control group (n = 30). All participants were subjected to anthropometric measurements, serum Angpt-2 and fasting lipid profile (total cholesterol, triglycerides, LDL-C, HDL-C, and Non-HDL-C) assessment. Glomerular filtration rate was estimated based on serum creatinine (eGFR-Cr). Higher serum Angpt-2 levels were detected in both diabetic groups compared to controls and in microalbuminuric compared to non-albuminuric diabetic group. There was no detected significant difference in eGFR-Cr values across the study groups. Serum Angpt-2 was positively correlated with triglycerides, LDL, Non-HDL-C, HbA1c, and UACR, while UACR, HbA1c, and Non-HDL-C were independent predictors for serum Angpt-2. Serum Angpt-2 at level of 137.4 ng/L could discriminate between microalbuminuric and non-albuminuric diabetic groups with AUC = 0.960 and at level of 115.95 ng/L could discriminate between the non-albuminuric diabetic group and controls with AUC = 0.976.Conclusion: Serum Angpt-2 is a promising potent biomarker for the detection of early stage of DKD in childhood T1DM before albuminuria emerges. What is Known? • Urine albumin-to-creatinine ratio (UACR) and glomerular filtration rate (GFR) are the golden standard but late biomarkers for DKD. • Angiopoietin-2 has been implicated in the development and progression of DKD in adults with diabetes, but has not been explored in T1DM children with DKD. What is New? • Higher serum angiopoietin-2 was detected in diabetic groups compared to controls and in microalbuminuric compared to non-albuminuric group. • Angiopoietin-2 correlated positively with triglycerides, LDL, Non-HDL-C, HbA1c, and UACR. • Serum angiopoietin-2 is a promising early diagnostic biomarker for DKD in children with T1DM.

Diagnostic value of serum cystatin C for diabetic nephropathy: a meta-analysis

BACKGROUND

Although dozens of studies have investigated the relationship between the content of serum cystatin C (Cys-C) and diabetic nephropathy (DN), the results are still controversial. Hence, This study aims to explore the accuracy of serum Cys-C for diagnosing DN by meta-analysis.

METHODS

The studies about serum Cys-C diagnosing DN were searched from six online databases from inception to September 22, 2020. The data were processed by Stata 15.0 statistic software. The corresponding diagnostic effect sizes, such as sensitivity and specificity, were obtained. We drew a summary receiver operating characteristic (SROC) curve. We assess the risk of literature bias was following the QUADAS-2 guidelines.

RESULTS

Twenty-six published studies were identified. The results showed a pooled sensitivity of 0.86 (95% confidence interval (CI): 0.82-0.90), specificity of 0.89 (95%CI: 0.85-0.92), positive likelihood ratio of 7.59 (95%CI: 5.66-10.19), negative likelihood ratio of 0.16 (95%CI: 0.12-0.21), and diagnostic odds ratio of 48.03 (95%CI: 30.64-75.29). The area under the SROC curve was given a value of 0.94 (95%CI: 0.91-0.96).

CONCLUSION

Serum cystatin C has an excellent diagnostic value with good sensitivity and specificity for diabetic nephropathy.

Effects of Sodium-Glucose Cotransporter-2 Inhibitors on Urine Albumin to Creatinine Ratio in Type 2 Diabetes Mellitus Patients and Medication Care

OBJECTIVES

The purpose of this study was to explore the effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on urine albumin to creatinine ratio (UACR) in type 2 diabetes mellitus (T2DM) patients and to recommend appropriate medication care scheme.

METHODS

8371 T2DM patients from four dapagliflozin studies and two canagliflozin studies were collected for analyzing with nonlinear mixed effect model (NONMEM). The change rates of UACR from baseline were intended to be evaluation indicators.

RESULTS

In the present study, there was no significant difference in the effects on UACR using dapagliflozin or canagliflozin treatment in T2DM patients. The maximal effect (E _max) and the treatment duration of reaching half of E _max (ET₅₀) from SGLT-2 inhibitors on UACR in T2DM patients were -19.2% and 0.448 weeks, respectively. Further, the treatment duration to reach 25%, 50%, 75%, and 80% E _max was 0.150 weeks, 0.448 weeks, 1.344 weeks, and 1.792 weeks, respectively. Namely, for achieving the plateau period (80% of E _max) of SGLT-2 inhibitors on UACR in T2DM patients, 10 mg/day dapagliflozin (or 100 mg/day canagliflozin) should be taken for at least 1.792 weeks.

CONCLUSIONS

To our knowledge, the present study explored the effects of SGLT-2 inhibitors on UACR in T2DM patients, meanwhile, recommended appropriate medication care scheme for the first time.

Urinary cystatin C as a biomarker of early renal dysfunction in type 2 diabetic patients

AIMS

We aimed to evaluate urinary CysC (cystanin c) as an early marker of diabetic nephropathy in patients with type 2 diabetes and investigate the correlation of urinary CysC with albuminuria and GFR.

METHODOLOGY

This case-controlled study was conducted on 66 type 2 diabetic patients who were classified according to albuminuria into 3 groups and consisting of 20 healthy subjects as the control group. We assessed urinary CysC, urinary albumin excretion rate (UACR).

RESULTS

Urinary CysC levels were significantly higher in normoalbuminuric diabetic compared with healthy control and there was a progressive linear increase in urinary CysC levels with increasing albuminuria in the diabetic patients. Despite insignificant deference in creatinine between participants groups, we observed significant differences between these groups as regard eGFR, urinary CysC, and UACR. Urinary CysC did not have significant correlations with any clinical or biochemical parameters. Moreover, urinary CysC had a statistically significant association with albuminuria and eGFR.

CONCLUSION

Urinary CysC levels correlated with UACR and GFR. It is linked to subclinical tubular injury and can be an earlier marker of kidney involvement, even before albuminuria and it is less influenced by non-renal factors. Therefore, Urinary CysC is useful biomarker for early diagnosis of diabetic nephropathy.

Urinary Cyclophilin A and serum Cystatin C as biomarkers for diabetic nephropathy in children with type 1 diabetes

BACKGROUND

Currently, microalbuminuria is the gold standard for detection and prediction of diabetic nephropathy (DN). However, microalbuminuria appears once significant kidney damage has actually occurred.

OBJECTIVES

We investigated the diagnostic role of urinary Cyclophilin-A (uCypA), uCypA/creatinine ratio (uCypA/Cr) and serum Cystatin-C (sCysC) as biomarkers for early detection of DN in children with type 1 diabetes mellitus (T1DM) of short duration (2-5 years) before microalbuminuria emerges.

METHODS

uCypA, uCypA/Cr, and sCysC levels were assessed in three age- and sex-matched groups; microalbuminuric diabetic group (n = 31), normoalbuminuric diabetic group (n = 29), and control group (n = 30). Glomerular filtration rate was estimated (eGFR) based on both serum creatinine (eGFR-Cr) and sCysC (eGFR-CysC).

RESULTS

Significantly higher sCysC and lower eGFR-CysC were detected in both diabetic groups compared to controls and in microalbuminuric compared to normoalbuminuric group. No detected significant difference in eGFR-Cr values across the studied groups. Both uCypA and uCypA/Cr were significantly elevated in microalbuminuric compared to both normoalbuminuric and control groups with no difference between normoalbuminuric and control groups. Prediction of microalbuminuria was conducted using sCysC with area under curve up to 0.980. Combined use of sCysC and uCypA had better diagnostic value than uCypA alone.

CONCLUSION

sCysC is a promising early biomarker for DN in childhood T1DM before albuminuria detection. eGFR-CysC is superior to eGFR-Cr in evaluating renal status in childhood T1DM. uCypA and uCypA/Cr were useful tools in predicting microalbuminuria, although not regarded as diagnostic biomarkers for early-stage DN in T1DM children by the current study.

Zinc alpha 2 glycoprotein as an early biomarker of diabetic nephropathy in patients with type 2 diabetes mellitus

INTRODUCTION

Although microalbuminuria remains the gold standard for early detection of diabetic nephropathy (DN), it is not a sufficiently accurate predictor of DN risk. Thus, new biomarkers that would help to predict DN risk earlier and possibly prevent the occurrence of end-stage kidney disease are being investigated.

OBJECTIVE

To investigate the role of zinc-alpha-2-glycoprotein (ZAG) as an early marker of DN in type 2 diabetic (T2DM) patients.

METHODS

88 persons were included and classified into 4 groups: Control group (group I), composed of normal healthy volunteers, and three patient groups with type 2 diabetes mellitus divided into: normo-albuminuria group (group II), subdivided into normal eGFR subgroup and increased eGFR subgroup > 120 mL/min/1.73m2), microalbuminuria group (group III), and macroalbuminuria group (group IV). All subjects were submitted to urine analysis, blood glucose levels, HbA1c, liver function tests, serum creatinine, uric acid, lipid profile and calculation of eGFR, urinary albumin creatinine ratio (UACR), and measurement of urinary and serum ZAG.

RESULTS

The levels of serum and urine ZAG were higher in patients with T2DM compared to control subjects and a statistically significant difference among studied groups regarding serum and urinary ZAG was found. Urine ZAG levels were positively correlated with UACR. Both ZAG levels were negatively correlated with eGFR. Urine ZAG levels in the eGFR ˃ 120 mL/min/1.73m2 subgroup were higher than that in the normal eGFR subgroup.

CONCLUSION

These findings suggest that urine and serum ZAG might be useful as early biomarkers for detection of DN in T2DM patients, detectable earlier than microalbuminuria.

Diabetic nephropathy in type 1 diabetes: a review of early natural history, pathogenesis, and diagnosis

Diabetic nephropathy constitutes a devastating complication in patients with type 1 diabetes mellitus, and its diagnosis is traditionally based on microalbuminuria. The aim of this review is to update through the medical literature the suggested early natural course of diabetic nephropathy, the theories behind the pathways of its pathogenesis, and its diagnosis. Poor glycemic control, dyslipidemia, smoking, advanced glycation end products, and environmental and genetic clues play an important role in the development of diabetic nephropathy. Microalbuminuria has been traditionally considered as a primary early marker of microvascular complication unraveling the risk for progress to the advanced stages of chronic kidney disease, but because of our inability to make an early diagnosis of diabetic nephropathy in young patients as well as nonalbuminuric diabetic nephropathy, recently, other additional markers of renal injury like serum and urinary neutrophil gelatinase-associated lipocalin, chitinase-3-like protein 1, cystatin C, and plasma growth differentiation factor 15 have been proposed to unmask early renal dysfunction, even before microalbuminuria supervenes. Copyright © 2016 John Wiley & Sons, Ltd.

NGAL as an Early Predictive Marker of Diabetic Nephropathy in Children and Young Adults with Type 1 Diabetes Mellitus

AIMS

Type 1 diabetes (T1D) is often associated with early microvascular complications. Previous studies demonstrated that increased systolic (SAP) and diastolic arterial blood pressures (DAP) are linked to microvascular morbidity in T1D. The aim of the study was to investigate the predictive role of neutrophil gelatinase-associated lipocalin (NGAL) in unravelling early cardio-renal dysfunction in T1D.

METHODS

Two T1D patient groups participating in two-centre prospective cohorts were studied. Group A consisted of 57 participants aged 13.9 years (SD: 3.1) and group B consisted of 59 patients aged 28.0 years (SD: 4.4). Forty-nine healthy children [age: 10.5 years (SD: 6.6)] and 18 healthy adults [age 27.7 years (SD: 4.2)] served as controls. Serum concentrations of NGAL (ELISA) were determined, and SAP and DAP were examined (SAP and DAP also expressed as z-scores in the younger group).

RESULTS

NGAL correlated positively with SAP in both patient groups (P = 0.020 and P = 0.031, resp.) and SAP z-score (P = 0.009) (group A) and negatively with eGFR in both groups (P < 0.001 and P < 0.001, resp.).

CONCLUSIONS

NGAL may be proposed as a biomarker of early renal dysfunction even in nonalbuminuric T1D patients, since it was strongly associated with renal function decline and increasing systolic arterial pressure even at prehypertensive range in people with T1D, in a broad age range.

Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients.

Assessment of Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Retinol-Binding Protein 4 (RBP4) in Type 2 Diabetic Patients with Nephropathy

Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes. The study aims to evaluate the diagnostic value of serum neutrophil gelatinase-associated lipocalin (NGAL) and retinol-binding protein 4 (RBP4) as biomarkers for early detection of nephropathy in type 2 diabetic patients. The current study was performed on 150 type 2 diabetic patients. These patients were classified into three equal groups according to their albumin/creatinine ratio (ACR), including patients with normoalbuminuria (ACR <30 mg/g creatinine), patients with microalbuminuria (ACR = 30-300 mg/g creatinine), and patients with macroalbuminuria (ACR >300 mg/g creatinine). Fifty apparently healthy subjects matching the same age and socioeconomic status with diabetic subjects were selected as a control group. The plasma glucose, insulin, glycosylated hemoglobin (HbA1c), homeostasis model assessment of insulin resistance (HOMA-IR), lipid profile, urea, creatinine, cystatin C, glomerular filtration rate (GFR), NGAL, and RBP4 were measured in the studied groups. Significantly elevated NGAL and RBP4 levels were observed in micro- and macroalbuminuric diabetic groups when compared to the control and normoalbuminuric diabetic groups. NGAL and RBP4 were found to correlate positively with duration of diabetes, systolic and diastolic blood pressure, glucose, HbA1c, HOMA-IR, triacylglycerol, and ACR, but correlate inversely with GFR in DN groups. Receiver operating characteristic curves revealed that for early detection of DN, the best cutoff values to discriminate DN and diabetic without nephropathy groups were 91.5 ng/mL for NGAL with 87% sensitivity, 74% specificity, and area under the curve (AUC) = 0.881; 24.5 ng/mL for RBP4 with 84% sensitivity, 90% specificity, and AUC = 0.912; and 37.5 mg/g creatinine for ACR with 89% sensitivity, 72% specificity, and AUC = 0.819. RBP4 is more specific (90% specificity) than NGAL (74% specificity) and ACR (72% specificity). Therefore, RBP4 marker may serve as a tool to follow-up clinical monitoring of the development and progression of DN.

Cystatin C: A Marker for Inflammation and Renal Function Among HIV-infected Children and Adolescents

BACKGROUND

Renal disease is a leading cause of morbidity in HIV-infected adults in the highly active antiretroviral therapy (HAART) era. Cystatin C has been proposed as a more sensitive marker of renal function, but it may be affected by ongoing inflammation. We aimed to study the cystatin C levels in a cohort of HIV-infected pediatric patients at 3 Spanish centers.

METHODS

This is a multicenter cross-sectional observational study. Renal function was assessed by means of first morning urine protein/creatinine and albumin/creatinine ratios and creatinine-estimated glomerular filtration rates (GFRs), together with the following inflammation markers: cystatin C, reactive C protein, β-2-microglobulin and 25(OH)-vitamin D levels. A control group of healthy children and adolescents was used.

RESULTS

Eighty-three patients (51 females, median age: 13.3 years; 32 males, median age: 13.6 years) and 44 controls (24 females, median age: 12.2 years; 20 males, median age: 10.9 years) were included. Among the former, mean CD4 cell count was 860/mm, 29(35%) patients had a previous AIDS diagnosis, 73(88%) were on HAART and HIV viremia was undetectable in 61(73%). No differences in cystatin C levels were observed between the 2 groups. In HIV-infected patients, cystatin C levels correlated with GFR (r = -0.27; P = 0.01), age at first HAART (r = -0.21; P = 0.05), and β-2-microglobulin (r = 0.569; P < 0.01). In multivariate analysis, lower GFR (P = 0.014) and higher β-2-microglobulin levels (P = 0.001) remained as independent risk factors for higher cystatin C values.

CONCLUSIONS

Cystatin C values were associated with GFR and β-2-microglobulin. Cystatin C may be useful as a marker of renal function in HIV-infected pediatric patients, independently of ongoing inflammation or viremia.

Microalbuminuria is independently associated with arterial stiffness and vascular inflammation but not with carotid intima-media thickness in patients with newly diagnosed type 2 diabetes or essential hypertension

The association between microalbuminuria (MAU) and the indices of macrovascular complication in patients with newly diagnosed type 2 diabetes (D) or essential hypertension (H) was evaluated. Total 446 patients were classified into four groups according to the urinary albumin-to-creatinine ratio: MAU-D (n = 104), normoalbuminuria (NAU)-D (n = 114), MAU-H (n = 116), and NAU-H (n = 112). The indices of macrovascular complication including arterial stiffness evaluated by pulse-wave-velocity (PWV), carotid intima-media thickness (IMT), and vascular inflammation marked by high-sensitivity C-reactive protein (hsCRP) were assessed. PWV, IMT, and hsCRP were higher in patients with MAU than in those with NAU in both diabetes and hypertension groups. In both MAU-D and MAU-H groups, PWV and hsCRP levels were positively correlated with MAU level (MAU-D: r = 0.47, 0.41, MAU-H: r = 0.36, 0.62, respectively, P < 0.05). Additionally, PWV and hsCRP were independent factors predicting MAU (diabetes group: OR 1.85, 1.54, hypertension group: OR 1.38, 1.51, respectively, P < 0.001), but not IMT. MAU is independently associated with arterial stiffness and vascular inflammation but not with IMT in patients with newly diagnosed type 2 diabetes or essential hypertension, which emphasizes the importance of proactive clinical investigations for atherosclerotic complications in patients with MAU, even in newly diagnosed diabetes or hypertension.