Genotype-phenotype correlations in children with Gitelman syndrome.

BACKGROUND: This study aimed to analyze genotype-phenotype correlations in children with Gitelman syndrome (GS). METHODS: This multicenter retrospective study included 50 Korean children diagnosed with SLC12A3 variants in one or both alleles and the typical laboratory findings of GS. Genetic testing was performed using the Sanger sequencing except for one patient. RESULTS: The median age at the diagnosis was 10.5 years (interquartile range, 6.8;14.1), and 41 patients were followed up for a median duration of 5.4 years (interquartile range, 4.1;9.6). A total of 30 different SLC12A3 variants were identified. Of the patients, 34 (68%) had biallelic variants, and 16 (32%) had monoallelic variants on examination. Among the patients with biallelic variants, those (n = 12) with the truncating variants in one or both alleles had lower serum chloride levels (92.2 ± 3.2 vs. 96.5 ± 3.8 mMol/L, P = 0.002) at onset, as well as lower serum potassium levels (3.0 ± 0.4 vs. 3.4 ± 0.3 mMol/L, P = 0.016), and lower serum chloride levels (96.1 ± 1.9 vs. 98.3 ± 3.0 mMol/L, P = 0.049) during follow-up than those without truncating variants (n = 22). Patients with monoallelic variants on examination showed similar phenotypes and treatment responsiveness to those with biallelic variants. CONCLUSIONS: Patients with GS who had truncating variants in one or both alleles had more severe electrolyte abnormalities than those without truncating variants. Patients with GS who had monoallelic SLC12A3 variants on examination had almost the same phenotypes, response to treatment, and long-term prognosis as those with biallelic variants.

Lower albumin level and longer disease duration are risk factors of acute kidney injury in hospitalized children with nephrotic syndrome.

BACKGROUND: Children with nephrotic syndrome (NS) are at an increased risk of acute kidney injury (AKI) and the incidence of AKI in this population is reportedly increasing. This study aimed to investigate the incidence, clinical profiles, and risk factors of AKI in hospitalized children with NS through a nationwide study. METHODS: This retrospective multicenter study included 14 pediatric nephrology centers in Korea. From 2013 to 2017, a total of 814 patients with idiopathic NS were cared for at participating centers. Among them, 363 patients were hospitalized for NS and investigated in this study. RESULTS: A total of 363 children with NS were hospitalized 574 times. AKI occurred in 93 admissions (16.2%) of 89 patients: 30 (32.3%) stage 1; 24 (25.8%) stage 2; and 39 (41.9%) stage 3. Multivariate logistic regression analysis showed that longer disease duration, lower albumin level, and methylprednisolone pulse treatment were significantly associated with AKI development in hospitalized children with NS. AKI was associated with a longer hospital stay than non-AKI (median 10 vs. 7 days, P = 0.001). Among 93 admissions, 85 (91.4%) episodes recovered from AKI without complication, whereas 6 (6.5%) progressed to advanced chronic kidney disease (CKD). CONCLUSIONS: AKI is not uncommon in hospitalized children with NS, and its incidence in this nationwide study was 16.2%. Risk factors for AKI in hospitalized children with NS include longer disease duration, lower albumin level, and methylprednisolone pulse therapy. Pediatric NS patients with these characteristics should be under more strict scrutiny for the occurrence of AKI. Graphical abstract.

Genetic variations in MicroRNA genes and cancer risk: A field synopsis and meta-analysis.

BACKGROUND: Cancer risk has been associated with certain gene variations in microRNA (miRNA), but conflicting evidence warrants re-assessing of significant results in meta-analyses. We summarized published meta-analyses that assess the associations between miRNA polymorphism and cancers to show the validity of the findings. METHOD: We searched PubMed and investigated the results of meta-analyses published through November 2018. We re-assessed the results based on false-positive report probability (FPRP) to test the noteworthiness of the associations. RESULTS: Sixty-eight miRNA polymorphisms in 45 meta-analyses associated with cancer were included. Four (7.4%) and sixteen (25.0%) single nucleotide polymorphisms (SNPs) were noteworthy (FPRP < 0.2) at a prior probability of 0.001 for interesting candidate genes and a statistical power to detect an odds ratio (OR) of 1.1 and 1.5, respectively. The four miRNA SNPs noteworthy at an OR of 1.1 were as follows: miR-146a/rs2910164 Cvs.G; miR-27a/rs895819 Cvs.T; miR-423/rs6505162 Cvs.A; and miR-605/rs2043556 Cvs.T. The 16 SNPs noteworthy at an OR of 1.5 include the four genotype comparisons at an OR of 1.1, and the additional 12 genotype comparisons were as follows: miR-196a2/rs11614913 Tvs.C; miR-27a/rs895819 GGvs.AA + AG; miR-196a2/rs11614913 C vs.T; miR-146a/rs2910164 Gvs.C; miR-196a2/rs11614913 Tvs.C; miR-146a/rs2910164 Cvs.G; miR-499/rs3746444 homozygous model; miR-146a/rs2910164 CCvs.GG + GC; miR-499/rs3746444 TCvs.TT; miR-499/rs3746444 GAvs.AA; miR-146a/rs2910164 CCvs.GG; and miR-499/rs3746444 Gvs.A. No association was noteworthy at a prior probability of 0.000001. CONCLUSION: Out of 68 published associations of miRNA polymorphisms with cancer, sixteen have shown noteworthiness in our re-assessing meta-analysis. Our findings summarize the results of meta-analyses on the association of cancer with SNPs and underline the importance of interpreting results with caution.

Urinary markers in the early stage of nephropathy in patients with childhood-onset type 1 diabetes.

BACKGROUND: The aim of this study was to evaluate the association of a urinary tubular marker, liver-type fatty acid binding protein (L-FABP) and an inflammatory marker, serum/urinary YKL-40, with albuminuria in patients with childhood-onset type 1 diabetes (T1D). METHODS: Twenty-nine patients with childhood-onset T1D and 32 controls were enrolled. Serum and urinary concentrations of YKL-40 and urinary concentrations of L-FABP were measured. RESULTS: The serum levels of YKL-40 were not significantly different between the control group and the patient groups. However, the levels of urinary YKL-40/creatinine (Cr) were higher in the patients, even those with normoalbuminuria than in the controls (p < 0.001). The levels of urinary L-FABP/Cr were not different between the control group and the patient groups. However, the level of urinary L-FABP/Cr in the microalbuminuria group was higher than that in the normoalbuminuria group (p = 0.03). There were no associations between the levels of urinary albumin-to-creatinine ratio and urinary L-FABP/Cr or YKL-40/Cr. However, the urinary L-FABP/Cr level was significantly correlated with the hemoglobin A1C level (p = 0.005) and the urinary YKL-40/Cr level (p = 0.043). CONCLUSIONS: Urinary L-FABP/Cr and YKL-40/Cr may reflect renal injury in early stages of nephropathy in patients with childhood-onset T1D, even in the normoalbuminuric state.

Asymptomatic hematuria in children: Korean Society of Pediatric Nephrology recommendations for diagnosis and management.

Hematuria is a relatively common condition among school-aged children. Because international guidelines for asymptomatic hematuria in children are unavailable, developing practical guidelines for the diagnosis and management of asymptomatic hematuria based on scientific evidence while considering real-world practice settings, values, and patient and physician preferences is essential. The Korean Society of Pediatric Nephrology developed clinical guidelines to address key questions regarding the diagnosis and management of asymptomatic hematuria in children.

A nationwide study of mass urine screening tests on Korean school children and implications for chronic kidney disease management.

BACKGROUND: Since 1998, urine screening tests have been performed on school children in Korea. We report the findings of the screening program that analyzed patients with proteinuria and/or hematuria. METHODS: Between 1999 and 2008, 5,114 children were referred to pediatric nephrologists at seven nationwide hospitals. Renal biopsies were performed on 1,478 children [28.79 % of total subjects; 26.77 % for isolated hematuria (IH), 9.09 % for isolated proteinuria (IP), and 51.19 % for combined hematuria and proteinuria (CHP)] who showed abnormal renal function, persistent hematuria and/or proteinuria for more than 6 months, nephrotic-range proteinuria, or those with underlying systemic diseases. RESULTS: Chronic glomerulonephritis (GN) was detected in 25 % of all visiting subjects. The most common findings in renal biopsies were immunoglobulin A (IgA) nephropathy in 38.97 %, mesangial proliferative GN in 24.29 %, and thin basement membrane nephropathy in 13.13 %. Compared with the relative frequency of renal diseases associated with urinary abnormalities, CHP (46.90 %) and nephrotic-range proteinuria (69.96 %) groups had more frequent GN than the others. Abnormal findings on renal ultrasound with or without Doppler scan were noted in 462 cases (suspected nutcracker phenomenon, 159; increased parenchymal echogenicity, 92; hydronephrosis, 75; simple cyst, 47). CONCLUSION: Mass urine screening tests could detect asymptomatic GN in its early stages. Initial aggressive diagnosis and treatment for CHP and nephrotic-range groups may prove helpful as interventions that delay chronic kidney disease progression. These findings may assist in the development of diagnostic and management guidelines for relatively mild urinary abnormalities, such as IH or low-grade IP.

Clinical relevance of blood urea nitrogen to serum albumin ratio for predicting bacteremia in very young children with febrile urinary tract infection.

Background: Urinary tract infections (UTIs) are one of the most common bacterial infections in febrile children and a common cause of hospitalization, especially in very young children. We examined the clinical characteristics and predictive factors of concomitant bacteremia in pediatric patients with febrile UTI aged ≤24 months. Methods: This retrospective multicenter study reviewed medical data from 2,141 patients from three centers from January 2000 to December 2019. Enrolled cases were classified into the bacteremic UTI and non-bacteremic UTI groups according to the presence of blood culture pathogens. Results: Among 2,141 patients with febrile UTI, 40 (1.9%) had concomitant bacteremia. All patients in the bacterial group were aged ≤6 months. Multivariate analysis revealed that younger age, lower blood lymphocyte counts and serum albumin levels, higher C-reactive protein (CRP) levels, blood urea nitrogen (BUN) levels, and BUN/serum albumin ratio were independent risk factors of concomitant bacteremia. The area under the receiver-operating characteristic curves predicting bacteremia were 0.668 for CRP, 0.673 for lymphocytes, and 0.759 for the BUN/albumin ratio. Conclusion: The present study identified the BUN/albumin ratio and lower blood lymphocyte counts as novel predictive factors for bacteremia in young infants with febrile UTI in addition to the previously identified factors of younger age and higher CRP levels. Our findings could help to identify patients at high risk of bacteremia and benefit decision-making in the management of infants with febrile UTI.

Genotype-phenotype correlation of X-linked Alport syndrome observed in both genders: a multicenter study in South Korea.

The genotype-phenotype correlation of the X-linked Alport syndrome (XLAS) has been well elucidated in males, whereas it remains unclear in females. In this multicenter retrospective study, we analyzed the genotype-phenotype correlation in 216 Korean patients (male:female = 130:86) with XLAS between 2000 and 2021. The patients were divided into three groups according to their genotypes: the non-truncating group, the abnormal splicing group, and the truncating group. In male patients, approximately 60% developed kidney failure at the median age of 25.0 years, and kidney survival showed significant differences between the non-truncating and truncating groups (P < 0.001, hazard ratio (HR) 2.8) and splicing and truncating groups (P = 0.002, HR 3.1). Sensorineural hearing loss was detected in 65.1% of male patients, while hearing survival periods showed a highly significant difference between the non-truncating and truncating groups (P < 0.001, HR 5.1). In female patients, approximately 20% developed kidney failure at the median age of 50.2 years. The kidney survival was significantly different between the non-truncating and truncating groups (P = 0.006, HR 5.7). Our findings support the presence of genotype-phenotype correlation not only in male patients but also in female patients with XLAS.

Association between lymphotoxin beta receptor gene polymorphisms and IgA nephropathy in Korean children.

Lymphotoxin beta receptor (LTBR) is essential for development and organization of the secondary lymphoid tissues. To investigate whether LTBR polymorphisms are associated with IgA nephropathy (IgAN) in Korean children, One hundred ninety nine patients with IgAN and 289 controls were recruited. Two promoter single nucleotide polymorphisms (SNPs) (rs3759333, -1387C/T and rs3759334, -1326A/G) and one coding SNP (rs2364480, Ala172Ala) in LTBR gene were selected and genotyped by direct sequencing. For analysis of data, SNPStats, SPSS 18.0, and Haploview version 4.2 were used. Multiple logistic regression models (codominant 1, codominant 2, dominant, and recessive models) were performed for odds ratio (OR), 95% confidence interval (CI), and p value. The rs3759334 was significantly associated with IgAN in codominant 1 (G/G vs. A/G, p = 0.025) and dominant (p = 0.017) models. The A alleles of rs3759334 and rs2364480 were related to risk of developing IgAN, respectively (rs3759334, p = 0.015; rs2364480, p = 0.041). Haplotypes CGC and TAA in LTBR gene were also associated with IgAN, respectively (CGC, p = 0.032 in codominant; TAA, p = 0.008 in codominant, p = 0.009 in dominant models). In conclusion, results suggest that LTBR gene polymorphisms may be associated with risk of IgAN in Korean children.

The clinical significance of serum cystatin C in critically ill newborns with normal serum creatinine.

BACKGROUND: The aim of this study is to evaluate the clinical significance of cystatin C(CysC) in the newborns who show normal serum creatinine (Cr) and who are in an intensive care unit. METHODS: From July 2009 to May 2010, a total of 106 patients (53 male and 53 female newborns) in a neonatal intensive care unit at Kyung Hee Medical Center were enrolled in this study. When clinicians ordered CysC, it was tested using HiSens Cystatin-C LTIA(HBi, An-yang, Korea) on a Toshiba chemical analyzer (Toshiba, Nasushiobara, Japan). RESULTS: The range of serum Cr and CysCwas from 0.1 to 0.8 mg/dL and from 1.0 to 2.3 mg/L, respectively. CysCpresented the wider amplitude of the changes in acute renal failure. CONCLUSION: In this study, CysCwithout an increased Cr showed only a mild increase. However, CysCreflected more delicate changes in newborns than the serum Cr. This characteristic of CysCcould make it very appropriate for a pediatric population, especially for critically ill newborns.

High Glycated Hemoglobin Instead of High Body Mass Index Might Increase the Urine N-Acetyl-ß-D-glucosaminidase Con-Centration in Children and Adolescents with Diabetes Mellitus.

Children with diabetes, and particularly those with obesity, have poor glycemic control. They are thus at higher risk of early microvascular complications. Renal tubulointerstitial markers are integral to evaluating diabetic nephropathy. Various biomarkers have been proposed, but their role in the obese pediatric population is uncertain. We investigated renal injury markers in children with diabetes, according to obesity, and determined their role as early predictors of diabetic nephropathy. Fifty-three children and adolescents, diagnosed with either type 1 or 2 diabetes mellitus, and 43 control children, aged 7-18 years, were included. Clinical and laboratory characteristics, including six renal injury markers, were compared among subjects according to body mass index and presence of diabetes mellitus. Urine neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, and N-acetyl-ß-D-glucosaminidase (NAG) showed significant difference between controls and diabetic children, whereas urine NAG was the only biomarker that was significantly lower either in non-obese or obese controls as compared to diabetic children. Urine NGAL, KIM-1, and NAG showed significant correlations with both HbA1c and urine ACR, whereas only urine NAG was significantly correlated with HbA1c even when groups were subdivided based on the presence of either obesity or diabetes. After adjusting for age, sex, body mass index, duration of known diabetes, and urine albumin-to-creatinine ratio, HbA1c remained a significant risk factor for elevated urine NAG. Urine NAG could be a useful indicator of tubulointerstitial damage in children with diabetes in the pre-albuminuric state. Tighter glycemic control appears to be crucial for avoiding early progression to diabetic nephropathy.

Korean Society of Nephrology 2022 recommendations on controversial issues in diagnosis and management of hyponatremia.

The Korean Society for Electrolyte and Blood Pressure Research, in collaboration with the Korean Society of Nephrology, has published a clinical practice guideline (CPG) document for hyponatremia treatment. The document is based on an extensive evidence-based review of the diagnosis, evaluation, and treatment of hyponatremia with the multidisciplinary participation of representative experts in hyponatremia with methodologist support for guideline development. This CPG consists of 12 recommendations (two for diagnosis, eight for treatment, and two for special situations) based on eight detailed topics and nine key questions. Each recommendation begins with statements graded by the strength of the recommendations and the quality of the evidence. Each statement is followed by rationale supporting the recommendations. The committee issued conditional recommendations in favor of rapid intermittent bolus administration of hypertonic saline in severe hyponatremia, the use of vasopressin receptor antagonists in heart failure with hypervolemic hyponatremia, and syndrome of inappropriate antidiuresis with moderate to severe hyponatremia, the individualization of desmopressin use, and strong recommendation on the administration of isotonic fluids as maintenance fluid therapy in hospitalized pediatric patients. We hope that this CPG will provide useful recommendations in practice, with the aim of providing clinical support for shared decision-making to improve patient outcomes.

Korean Society of Nephrology 2022 Recommendations on controversial issues in diagnosis and management of hyponatremia.

The Korean Society for Electrolyte and Blood Pressure Research, in collaboration with the Korean Society of Nephrology, has published a clinical practice guideline (CPG) document for hyponatremia treatment. The document is based on an extensive evidence-based review of the diagnosis, evaluation, and treatment of hyponatremia with the multidisciplinary participation of representative experts in hyponatremia with methodologist support for guideline development. This CPG consists of 12 recommendations (two for diagnosis, eight for treatment, and two for special situations) based on eight detailed topics and nine key questions. Each recommendation begins with statements graded by the strength of the recommendations and the quality of the evidence. Each statement is followed by rationale supporting the recommendations. The committee issued conditional recommendations in favor of rapid intermittent bolus administration of hypertonic saline in severe hyponatremia, the use of vasopressin receptor antagonists in heart failure with hypervolemic hyponatremia, and syndrome of inappropriate antidiuresis with moderate to severe hyponatremia, the individualization of desmopressin use, and strong recommendation on the administration of isotonic fluids as maintenance fluid therapy in hospitalized pediatric patients. We hope that this CPG will provide useful recommendations in practice, with the aim of providing clinical support for shared decision-making to improve patient outcomes.

Korean Society of Nephrology 2022 Recommendations on Controversial Issues in Diagnosis and Management of Hyponatremia.

The Korean Society for Electrolyte and Blood Pressure Research, in collaboration with the Korean Society of Nephrology, has published a clinical practice guideline (CPG) document for hyponatremia treatment. The document is based on an extensive evidence-based review of the diagnosis, evaluation, and treatment of hyponatremia with the multidisciplinary participation of representative experts in hyponatremia with methodologist support for guideline development. This CPG consists of 12 recommendations (two for diagnosis, eight for treatment, and two for special situations) based on eight detailed topics and nine key questions. Each recommendation begins with statements graded by the strength of the recommendations and the quality of the evidence. Each statement is followed by rationale supporting the recommendations. The committee issued conditional recommendations in favor of rapid intermittent bolus administration of hypertonic saline in severe hyponatremia, the use of vasopressin receptor antagonists in heart failure with hypervolemic hyponatremia, and syndrome of inappropriate antidiuresis with moderate to severe hyponatremia, the individualization of desmopressin use, and strong recommendation on the administration of isotonic fluids as maintenance fluid therapy in hospitalized pediatric patients. We hope that this CPG will provide useful recommendations in practice, with the aim of providing clinical support for shared decision-making to improve patient outcomes.

Polymorphisms of insulin-like growth factor-1 (IGF-1) and IGF-1 receptor (IGF-1R) contribute to pathologic progression in childhood IgA nephropathy.

Previous studies have suggested that insulin-like growth factor-1 (IGF-1) signaling might play an important role in renal fibrosis and regulation of the proliferation of mesangial cells and podocytes. We conducted the present study to investigate association between single nucleotide polymorphisms (SNPs) of IGF-1 (IGF-1) and IGF-1 receptor (IGF-1R) genes and childhood immunoglobulin (Ig) A nephropathy (IgAN). We analyzed five SNPs of IGF-1 and IGF-1R in 188 pediatric IgAN patients and in 263 healthy controls. We compared variations in SNPs in several sets of IgAN subgroups that were designated based on the presence of nephrotic range proteinuria (>40 mg/m2 per h), podocyte foot process effacement, and pathological progression. Genotyping of IgAN patients and controls revealed differences in IGF-1R rs2229765. Moreover, the rs2195239, rs978458, and rs1520220 SNPs of IGF-1 showed significant association with pathological progression. Thus, in the present study, we observed associations between the IGF-1/1R pathway, susceptibility to IgAN, and the pathologic progression of IgAN.

Linkage and association study of neurotrophins and their receptors as novel susceptibility genes for childhood IgA nephropathy.

Neurotrophins (NTs) and their receptors (NTRs) are known to be important for pathogenesis of various inflammatory diseases that occur in not only neuronal but also nonneuronal tissues, including kidney. Here, we investigated association between childhood IgA nephropathy (IgAN) and single nucleotide polymorphisms (SNPs) of genes encoding NTs [nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF)] and NTRs [nerve growth factor receptor (NGFR) and neurotrophic tyrosine kinase receptor 1-3 (NTRK1-3)]. The genotyping data of 197 patients and 289 control subjects revealed significant association between NGF SNP rs11102930 and presence of IgAN. Patient subgroup analysis revealed that that the presence of nephrotic range proteinuria (>40 mg/m/h) was associated with rs6334 of NTRK1 and rs11030104, rs7103411, rs7103873, and rs6484320 of BDNF. Significant genotype differences were observed in podocyte foot process effacement for rs1187321 and rs1187323 of NTRK2. Furthermore, some SNPs showed significantly different genotype distribution between patients with or without pathologically advanced disease markers, specifically in rs6334 of NTRK1. Our results suggest that SNPs of NTs and NTRs are associated with susceptibility, pathological advancement, podocyte foot process effacement, and development of proteinuria in childhood IgAN.

Association between toll-like receptor 10 (TLR10) gene polymorphisms and childhood IgA nephropathy.

Toll-like receptors (TLRs) play an important role in the induction and regulation of the innate immune system and adaptive immune responses. TLR10 gene polymorphisms have been reported to be associated with a range of immune-related diseases. In this study, we investigated the association of TLR10 gene polymorphisms with immunoglobulin A nephropathy (IgAN) in Korean children. To examine the association, we genotyped one promoter single nucleotide polymorphisms (SNP) [rs10004195 (-113T/A)] and three missense SNPs [rs11096957 (Asn241His), rs11096955 (Ile369Leu), and rs4129009 (Ile775Val)] using direct sequencing in 199 IgAN patients and 289 control subjects. Our case-control analysis showed that rs10004195 was associated with IgAN (codominant model, p = 0.016 in TT vs. TA; p = 0.044 in TT vs. AA; dominant model, p = 0.0068). In addition, when comparing the proteinuria level of IgAN patients according to the genotypes of each SNP, we found that in dominant model of rs1004195, the level of proteinuria of patients with TA or AA genotypes (median, 4.01 mg/m(2)/h) was higher than that of patients with TT genotype (2.00 mg/m²/h, p = 0.033). In conclusion, these results suggest that TLR10 gene may be associated with susceptibility to IgAN in Korean children.

New susceptible locus, rs9428555, is associated with pediatric-onset immunoglobulin A nephropathy and immunoglobulin A vasculitis in Koreans.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is one of the most common primary forms of glomerulonephritis, while IgA vasculitis (IgAV) is the most common systemic vasculitis in children. OBJECTIVE: Herein we aimed to uncover single nucleotide polymorphism (SNP) markers associated with these two related diseases by applying association tests and Sanger sequencing. METHODS: Within the discovery stage, genomic DNA in blood samples from 101 enrolled patients were genotyped by the Korean Biobank Array. Association tests were performed with 397 Korean reference genomes. In the validation stage, 26 independent samples were genotyped by Sanger sequencing. RESULTS: Four SNPs were identified (P < 5 × 10-8) in the discovery stage. To determine whether the genotypes determined by SNP array were accurate, additional genotyping via Sanger sequencing was performed. As a result, only one SNP, rs9428555, was properly genotyped. In the validation stage, the minor allele (A > G) was found in as many as 15 out of 26 samples (minor allele frequency = 0.288), even though this minor allele is rare in East Asians (< 3%). CONCLUSIONS: We found rs9428555 as a novel susceptible locus associated with the development of both IgAN and IgAV in Koreans. Though we cannot conclude rs9428555 is the unique susceptible locus of IgAN and IgAV, it is likely a good marker as the minor allele of this SNP occurred much more often in the patient group here versus within East Asians as a whole.

Poor Glycemic Control Can Increase the Plasma Kidney Injury Molecule-1 Concentration in Normoalbuminuric Children and Adolescents with Diabetes Mellitus.

Diabetic nephropathy (DN) is a serious microvascular complication in childhood diabetes and microalbuminuria has been a solid indicator in the assessment of DN. Nevertheless, renal injury may still occur in the presence of normoalbuminuria (NA) and various tubular injury biomarkers have been proposed to assess such damage. This case-controlled study aimed to evaluate plasma and urinary neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 (KIM-1) levels in diabetic children particularly in those with normo- and high-NA stages and determine their role in predicting DN. Fifty-four children/adolescents with type 1 and 2 diabetes and forty-four controls aged 7-18 years were included. The baseline clinical and laboratory characteristics including plasma and urinary biomarkers were compared. The plasma KIM-1 levels were significantly higher in diabetic children than in the controls and in high-NA children than normo-NA children. Glycosylated hemoglobin (HbA1c) was identified as a significant risk factor for increased plasma KIM-1. The optimal cutoff for HbA1c when the plasma KIM-1 was > 23.10 pg/mL was 6.75% with an area under the curve of 0.77. For diabetic children with mildly increased albuminuria, the plasma KIM-1 complementary to MA may help increase the yield of detecting DN. Our findings also suggested an HbA1c cutoff of 6.75% correlated with increased plasma KIM-1.

Clinical Significance of the Fetuin-A-to-Adiponectin Ratio in Obese Children and Adolescents with Diabetes Mellitus.

Fetuin-A and adiponectin are inflammatory cytokines associated with obesity and insulin resistance. This study aimed to examine the fetuin-A-to-adiponectin ratio (FAR) in diabetic children and to determine the role of FAR. A total of 54 children and adolescents with diabetes mellitus (DM) and 44 controls aged 9-16 years were included in this study. Clinical characteristics, including plasma fetuin-A and adiponectin levels, were compared with respect to body mass index (BMI) and diabetes type. Of 98 children, 54.1% were obese, whereas 18.4% were obese and diabetic. FAR was higher in obese children with DM than in non-obese children and also in type 2 DM children than in type 1. FAR showed a stronger association with BMI than with fetuin-A and adiponectin individually, and its association was more prominent in diabetic children than in controls. BMI was a risk factor for increased FAR. Plasma fetuin-A was elevated in obese children, and its association with insulin resistance and ß cell function seemed more prominent in diabetic children after adjustment for adiponectin. Thus, FAR could be a useful surrogate for the early detection of childhood metabolic complications in diabetic children, particularly those who are obese.