Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

Background: Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially. Approach: An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence-Based Laboratory Medicine Committee of the American Association for Clinical Chemistry jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association. Content: In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A$_{1c}$ (HbA$_{1c}$) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of HbA$_{1c}$. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed. Summary: The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended

Pediatric and Adolescent Nephrology Facing the Future: Diagnostic Advances and Prognostic Biomarkers in Everyday Practice

The Special Issue entitled “Pediatric and adolescent nephrology facing the future: diagnostic advances and prognostic biomarkers in everyday practice” contains articles written in the era when COVID-19 had not yet been a major clinical problem in children. Now that we know its multifaceted clinical course, complications concerning the kidneys, and childhood-specific post-COVID pediatric inflammatory multisystem syndrome (PIMS), the value of diagnostic and prognostic biomarkers in the pediatric area should be appreciated, and their importance ought to increase

Smoking and Second Hand Smoking in Adolescents with Chronic Kidney Disease: A Report from the Chronic Kidney Disease in Children (CKiD) Cohort Study

The goal of this study was to determine the prevalence of smoking and second hand smoking [SHS] in adolescents with CKD and their relationship to baseline parameters at enrollment in the CKiD, observational cohort study of 600 children (aged 1-16 yrs) with Schwartz estimated GFR of 30-90 ml/min/1.73m2. 239 adolescents had self-report survey data on smoking and SHS exposure: 21 [9%] subjects had “ever” smoked a cigarette. Among them, 4 were current and 17 were former smokers. Hypertension was more prevalent in those that had “ever” smoked a cigarette (42%) compared to non-smokers (9%), p\u3c0.01. Among 218 non-smokers, 130 (59%) were male, 142 (65%) were Caucasian; 60 (28%) reported SHS exposure compared to 158 (72%) with no exposure. Non-smoker adolescents with SHS exposure were compared to those without SHS exposure. There was no racial, age, or gender differences between both groups. Baseline creatinine, diastolic hypertension, C reactive protein, lipid profile, GFR and hemoglobin were not statistically different. Significantly higher protein to creatinine ratio (0.90 vs. 0.53, p\u3c0.01) was observed in those exposed to SHS compared to those not exposed. Exposed adolescents were heavier than non-exposed adolescents (85th percentile vs. 55th percentile for BMI, p\u3c 0.01). Uncontrolled casual systolic hypertension was twice as prevalent among those exposed to SHS (16%) compared to those not exposed to SHS (7%), though the difference was not statistically significant (p= 0.07). Adjusted multivariate regression analysis [OR (95% CI)] showed that increased protein to creatinine ratio [1.34 (1.03, 1.75)] and higher BMI [1.14 (1.02, 1.29)] were independently associated with exposure to SHS among non-smoker adolescents. These results reveal that among adolescents with CKD, cigarette use is low and SHS is highly prevalent. The association of smoking with hypertension and SHS with increased proteinuria suggests a possible role of these factors in CKD progression and cardiovascular outcomes

5th Croatian Congress of Medical Biochemists with international participation

5. hrvatski kongres medicinskih biokemičara s međunarodnim sudjelovanjem Poreč, Hrvatska, 18.-22. listopada 2006. Program i sažeci kongresa5th Croatian Congress of Medical Biochemists with international participation Poreč, Croatia, October 18-22, 2006. Meeting Program and Abstract

Investigation of Biomarkers of Hepatic and Renal Toxicity in the Han Wistar Rat

The aim of this project was to identify urinary markers of hepatic and renal toxicity in the male Hanover-Wistar rat; acute and chronic injury models were developed by administration of CCl4. Nephrotoxicity was induced by administration of HCBD. In an acute dose study, CCl4-induced nephrotoxicity occurred above 2.0 mL/kg CCl4. To avoid kidney injury, 2.0 mL/kg CCl4 was chosen as the optimal dose. 1H NMR revealed many changes to the urinary metabolome following CCl4-induced liver injury including an increase in the resonances of taurine, creatine and formate and a decrease in hippurate and creatinine. Protein and gene expression markers were investigated in a HCBD-model of nephrotoxicity. Urinary α-GST, KIM-1 and albumin were the most sensitive biomarkers of proximal tubular injury. These markers could be used to detect unwanted kidney injury in future CCl4 hepatic studies. In a time course study, maximal liver injury from CCl4 was reached 24-48 hours post-dosing. Urinary metabolites followed the same trend and levels increased during the first 18-24 hours post-dosing. After 24 hours, there was a tendency for metabolites to return to control levels. A chronic model of CCl4-induced liver fibrosis was developed by dosing animals 3 times a week for 6 weeks to investigate the potential for reversibility and changes in urinary metabolites. After 6 weeks of CCl4-administration there was development of fibrous structures in the liver parenchyma followed by slight regeneration during the recovery period. Urinary metabolites that best reflected the development of fibrosis were creatinine, citrate and succinate. Taurine and hippurate may be useful for showing regenerative changes. In this project, we developed a good rat model of fibrosis which showed potential to reverse. 1H NMR analysis allowed characterisation of urinary metabolite changes in acute and chronic studies. Some of these metabolites have potential to be urinary markers for hepatic fibrosis

Investigating miR‐214 as a pro‐fibrotic mediator in renal fibrosis and its potential as a therapeutic target via effective in vivo modelling of chronic kidney disease

Chronic kidney disease (CKD) is a prevalent health condition in the UK and worldwide. CKD is defined as the progressive decline of renal filtrative capacity over time. High rates of cardiovascular dysfunction and related mortality are observed in patients with CKD. Renal fibrosis is the final common pathway though which all CKD, regardless of the initiating insult. Renal fibrosis, defined as excess collagenous matrix deposition that restricts renal filtrative capacity, is a complex process involving multiple cell types, biological pathways, cytokines and other pro‐fibrotic factors such as microRNAs (miRNAs). miRNAs are small non‐coding RNA which post‐transcriptionally regulate gene expression via inhibition of target mRNA translation. MicroRNA‐214‐3p (miR‐214) has been proposed to be a key pro‐fibrotic miRNA in renal fibrosis. Increased miR‐214 expression is found in CKD patient urine and kidney biopsies, correlating with degree of fibrosis, mirroring the increase observed in several in vitro and in vivo models. Knockdown of miR‐214 expression in the unilateral ureteral obstruction (UUO) model of renal fibrosis resulted in an 86% reduction in fibrosis, although the mechanism behind this remained largely unknown. Therefore, the hypothesis presented in this thesis is that miR‐214 functions as a pro‐fibrotic miRNA in renal fibrosis and effective in vivo modelling will allow for the investigation of its mechanism and assessment of its potential as a therapeutic target in progressive chronic kidney disease. The aims of this thesis are as follows. Firstly, to profile the refined mouse subtotal nephrectomy (STNx) model as a progressive model of CKD. Secondly, to evaluate an anti‐miR‐214 compound in vitro. Thirdly, to assess the therapeutic potential of antimiR‐ 214 as an intervention in STNx. Fourthly, to profile the miRNA and gene expression changes observed in individual renal cell populations in UUO and reversible UUO (rUUO). Lastly, to use the generated data to explore potential profibrotic mechanisms of miR‐214 in renal fibrosis on a cell‐population specific basis. Subtotal nephrectomy is an in vivo model of CKD, which, unlike UUO, allows for the measurement of clinically‐relevant renal functional parameters, produces glomerulosclerosis and cardiovascular dysfunction, and has a history of successful translation of findings to clinical practice. The refined subtotal nephrectomy (STNx) 10‐week model presented here attempts to overcome downsides in the traditional model; performed as a single‐surgery with improved survival, animal welfare and consistent outcomes. The STNx model was fully characterised and then used to assess the effects of miR‐214 inhibition (via anti‐miR) in this more translatable model of CKD. The anti‐miR‐214 compound, provided by Regulus Therapeutics, was first assessed in vitro, where its affinity for miR‐214 was found to be high and a reduction in profibrotic gene expression was observed in TGFβ‐stimulated renal fibroblasts. Intervention with anti‐miR‐214 in STNx was initiated at 6‐weeks post‐STNx to assess anti‐miR‐214 efficacy in a situation where renal fibrosis and dysfunction were already present, as diagnosis and therapeutic intervention in CKD usually do not occur until renal fibrosis and dysfunction are already present. Here, anti‐miR‐214 intervention did not produce any significant changes across a number of renal and cardiovascular parameters measured compared to control anti‐miR. Lack of efficacy may have been due to the timing of the intervention, lack of anti‐miR penetration to the appropriate cell types, or lack of efficacy of anti‐miR‐214 in STNx in general. As miR‐214 is known to have diverse and even opposing roles in different cell types and pathologies, elucidating the expression of miR‐214 in renal cell types may be critical to understanding its mechanisms in renal fibrosis. In order to address this, the expression of miR‐214 was examined in a cell specific and temporal manner using the reversible UUO (rUUO) experimental model. This allowed for analysis of renal injury and resolution of renal injury. From the rUUO model, 4 cell populations known to play a role in renal fibrosis and injury resolution were FACS sorted and underwent RNA sequencing for miRNA and gene expression. miR‐214 was found to be significantly enriched in Pdgfrβ+ (myofibroblast‐like) cells in the kidney in comparison to proximal tubular epithelial cells, endothelial cells and tissue‐resident macrophages, indicating myofibroblasts are the primary site of mechanistic interest. Bioinformatic analysis revealed several predicted miR‐214 targets in Pdgfrβ+ cells, indicating miR‐ 214 may act as an anti‐apoptotic and/or pro‐proliferative factor in these cells in the context of renal fibrosis. In conclusion, the development and profiling of STNx provided a valuable platform for the assessment of anti‐miR‐214 as a therapeutic intervention in CKD, allowing the measurement of a variety of clinically‐relevant parameters including renal fibrosis. Anti‐miR‐214, despite displaying efficacy in vitro, did not ameliorate any renal or cardiovascular phenotypes induced by STNx. Four cell populations relevant to renal fibrosis were sorted from rUUO kidneys and RNA‐sequencing carried out to discover the gene and miRNA expression profiles in these cell types in renal injury and injury resolution. miR‐214 was found to be significantly enriched in Pdgfrβ+ (myofibroblastlike) cells. Bioinformatic analysis of miR‐214 targets in this cell population suggests miR‐214 may have an anti‐apoptotic and/or pro‐proliferative role