Morning Spot Research Articles

Accuracy of equations for predicting 24-h urinary potassium excretion from spot urine samples in Chinese children.

Accurate assessments of potassium intake in children are important for the early prevention of CVD. Currently, there is no simple approach for accurate estimation of potassium intake in children. We aim to evaluate the accuracy of 24-h urinary potassium excretion (24UKV) estimation in children using three common equations: the Kawasaki, Tanaka and Mage formulas, in a hospital-based setting. A total of 151 participants aged 5-18 years were initially enrolled, and spot urine samples were collected in the whole 24-h duration to measure the concentrations of potassium and creatinine. We calculated the mean difference, absolute and relative difference and misclassification rate between measured 24UKV and the predicted ones using Kawasaki, Tanaka and Mage formulas in 129 participants. The mean measured 24UKV was 1193·3 mg/d in our study. Mean differences between estimated and measured 24UKV were 1215·6, -14·9 and 230·3 mg/d by the Kawasaki, Tanaka and Mage formulas, respectively. All estimated 24UKV were significantly different from the measured values in all the time point (all P < 0·05), except for the predicted values from Tanaka formula using morning, afternoon and evening spot urine. The proportions with relative differences over 40 % were 87·2%, 32·5% and 47·3 % for Kawasaki, Tanaka and Mage formulas, respectively. Misclassification rates were 91·5 % for Kawasaki, 44·4 % for Tanaka and 58·9 % for Mage formula at the individual level. Our findings showed that misclassification could occur on the individual level when using Kawasaki, Tanaka and Mage formulas to estimate 24UKV from spot urine in the child population.

Randomized Controlled Trial of Simple Salt Reduction Instructions by Physician for Patients with Type 2 Diabetes Consuming Excessive Salt.

Objectives: We verified the clinical usefulness of an approach method in which a physician gives simple salt reduction instructions during outpatient visits to patients with type 2 diabetes. Methods: This study was an open-blind, randomized controlled trial. Subjects were outpatients with type 2 diabetes whose estimated salt intake using spot morning urine sample exceeded the target of salt intake. The control group (CG) was notified only of the current salt intake, whereas the intervention group (IG) was given the brief salt reduction instruction by a physician in addition to the information regarding their current salt intake. Results: The change in estimated salt intake was −0.6 g (from 10.1 to 9.5 g, p = 0.029) in the CG after 8 weeks, and −0.9 g (from 10.1 to 9.2 g, p = 0.001) in the IG, although there were no significant differences between them (p = 0.47). After 24 weeks, both groups no longer differed significantly from the baseline. In addition, multivariate linear regression analyses indicated that high salt intake and low estimated glomerular filtration rate at baseline were significantly associated with salt reduction after 8 weeks. Conclusions: Salt-reducing effects were observed after 8 weeks in both the IG and CG, but no significant difference was observed. Moreover, patients with high salt intake and renal disfunction may be more effective in accepting salt reduction instructions. Making patients aware of the importance of salt reduction through a physician is effective for continuous salt reduction, and it is important to continue regular and repetitive guidance.

The Hypofibrinolytic Defect of Nephrotic Syndrome Is Directly Proportional to Disease Severity

IntroductionNephrotic syndrome (NS) is characterized by massive proteinuria (secondary to podocyte injury), hypoalbuminemia, and edema. Increasing evidence suggests that myriad abnormalities of the hemostatic system may be implicated in the pathogenesis of thrombosis during NS. Indeed, thromboelastometry studies by our group and others have suggested a resistance to fibrinolysis in animal models of NS. Research on NS-associated fibrinolytic effects in human patients is scarce however and complicated by conflicting results and limited mechanistic investigations. The aim of the present study was to delineate the relationship between disease severity (proteinuria and hypoalbuminemia) and fibrinolysis using two rodent models of NS and a cohort of human NS patients. We hypothesized that hypofibrinolysis is directly proportional to NS disease severity.MethodsUsing two well established rat models of NS, transgenic diphtheria toxin receptor (DTR) and puromycin aminonucleoside (PAN), we compared markers fibrinolysis to disease severity. A range of severity was induced by a single I.P. injection of diphtheria toxin (0-75 ng/kg IP) or PAN (0-150 mg/kg IV). On day 10 post-injection, morning spot urines were collected and analyzed for protein:creatinine ratio (uPr:Cr). Rats were then anesthetized and venous blood (IVC) was collected into 0.32% NaCitrate/1.45 µM Corn Trypsin Inhibitor and immediately analyzed with ROTEM before being spun down to platelet poor plasma (PPP). Samples were also collected from a local cohort of pediatric and adult NS patients (n=23), along with the corresponding clinical lab data for each patient. Plasma clot lysis assay (CLA) was performed using urokinase (50 IU). Plasma clot turbidity was measured by inducing clot formation with recalified PPP + 0.5 pM TF + 4uM phospholipids, and monitoring absorbance at 405nm. Fibrinolytic markers in plasma were measured by ELISA. Plasmin generation (PG) has not previously been studied in rats, however our initial results suggested that PG is substantially prolonged in rats compared to humans. Thus, through a series of experiments we first developed a PGA protocol optimized for use in rats. Final PG results were obtained over 12 hours using an MCA-fluorogenic substrate with addition of 10 nM tissue plasminogen activator (tPA).ResultsHypofibrinolysis: The amount of lysis at 60 min (LI60) on ROTEM was significantly correlated with proteinuria in both the DTR and PAN models (R2=0.167; P=0.015 & R2=0.740; P<0.001, respectively). The addition of tranexamic acid to the ROTEM assay (1mg/100ul), abolished lysis (increased the LI60 to 100%) in both healthy and NS rats (~8% & 3.5% abolishment, respectively), suggesting that the increased clot stability is indeed a fibrinolytic defect. These findings were confirmed with the CLA, such that plasma clot lysis was significantly negatively correlated with proteinuria (R2=0.196; P=0.007 & R2=0.214; P=0.010) and significantly positively correlated with hypoalbuminemia (R2=0.310; P<0.001 & R2=0.240; P=0.006), in the DTR & PAN models, respectively. Additionally, plasma clot lysis by CLA was decreased in NS patients with uPrCr ≥2 (n=16) vs. <2 mg/mg (n=7) (96.1 vs 55.2 %, respectively; P=0.041).Mechanisms of Hypofibrinolysis: In the DTR rats, disease severity was positively correlated with plasma concentrations of Fibrinogen, uPA, PAI-1, and plasma turbidity at baseline and following clot formation, suggesting a difference in clot structure related to disease state.Plasmin Generation: After optimizing the protocol for rats, we were able to obtain evaluable PG curves (Figure). PG increased with disease severity such that it was highly correlated with proteinuria and hypoalbuminemia in both rat models (P<0.001; Figure), as well as in our human samples (P=0.005).ConclusionsThese data suggest that NS thrombi are resistant to fibrinolysis in a manner that is proportional to disease severity. Paradoxically, increased plasmin generation implies that the fibrinolytic system is hyperactive during NS. Thus it appears that the nephrotic clots are inherently resistant to fibrinolysis, even in the face of the increased plasmin that is generated. We are currently examining fibrin clot structure in NS, hypothesizing that nephrotic plasma forms a denser fibrin network that is resistant to fibrinolysis. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

MO537INTERACTION OF PLASMA HOMOCYSTIENE, RENAL FUNCTION AND CARDIO-METABOLIC RISK FACTORS- AN OBSERVATION IN A RURAL POPULATION OF BANGLADESH

Abstract Background and Aims Elevated plasma total homocystiene (tHcy) levels are associated with atherosclerotic diseases in coronary, cerebral and peripheral blood vessels. It is possible that hyperhomocysteinemia may lead to intrarenal arteriosclerotic lesions and decline in GFR or impaired renal function. Aim of this study was to elucidate the association of plasma homocystiene level with renal function and cardiovascular risk factors in rural population. Method A well defined rural area was selected. Study subjects were identified by computer generated random numbers after entering household listings and then Kish table was used to choose a participant. Adult subjects (≥18 years) were only included. The approached participant was explained the purpose, if consented, then given an appointment to be present at a research hospital on a separate date for clinical and biochemical evaluation. A face to face interview was conducted. Clinical history, physical examination anthropometrics were recorded on data sheet. Fasting blood sample and morning spot urine was collected. Then serum tHcy was measured by chemiluminescent microparticle immunoassay (CMIA) technology. Study population were investigated with Spot urine ACR, Fasting glucose, serum lipid profile, creatinine, homocysteinine , Folic acid and Vit B12. Results Early results of 234 random subjects are presented here. The mean age was 41 ± 13(18-92) years with male 33% and female 67%. Mean eGFR was 99± 26 ml/min, tHcy 11.6 ± 5.9 μmol/l, Vit B12 329 ± 187 pg/ml and Folic Acid 5.57 ± 2.63 ng/ml. A tHcy cut-off value in study subjects ≥15 μmol/l was seen in 17 % and &amp;lt;15 μmol/l in 83%. Serum creatinine, Uric Acid, Cholesterol, LDL was significantly higher and Vit B12, Folic acid lower in tHcy ≥15 μmol/l group. Further grouping showed tHcy level was significantly higher in Vit B12&amp;lt;200 pg/ml and Folic acid &amp;lt;3ng/l group. Correlation studies showed homocystiene positively correlated with age, systolic blood pressure, creatinine, LDL and negatively with Folic acid and Vit B12. Conclusion Our findings suggest that elevated plasma homocystiene level might influence and are associated with altered markers of renal, cardiac and metabolic risk factors in rural population. Preventive approaches are required towards this issue as larger population segment belongs to rural areas.

MO597ESTIMATING INDIVIDUAL-LEVEL SODIUM INTAKE WITH REPEATED SPOT URINE SAMPLING

Abstract Background and Aims In daily clinical practice, individual-level sodium (Na) intake is often estimated by measuring Na excretion in a single 24h urine collection, but long-term Na balance studies indicate that 7 consecutive 24h urine collections are needed. However, this approach is not feasible in clinical settings. In this study, we investigate whether the use of repeated spot urine sampling is an appropriate alternative for repeated 24h urine collections. Method We performed a post-hoc analysis of a metabolic ward study in 8 healthy male adults who consumed a 7-day diet with a fixed amount of Na (200 mmol/d). Urine was collected in four daily intervals: 7-13h, 13-19h, 19-23h and 23-7h. After reaching steady state, we estimated Na intake with 1 and 3 consecutive 24h urine collections and 3-day spot urine sampling, using the Kawasaki formula with measured 24h urine creatinine excretion. Results: On day 5, mean 24h Na excretion matched intake, indicating that steady state was achieved (Fig A). Mean and standard deviation of absolute differences between estimated and measured Na intake (ΔNa) for each method were: 18.8 ±14.6 mmol (3 x spot urine 7-13h), 32.3 ±18.7 mmol (3 x spot urine 13-19h), 74.6 ±30.0 mmol (3 x spot urine 19-23h), 28.2 ±19.8 mmol (3 x spot urine 23-7h), 29.8 ±23.9 mmol (1 x 24h urine) and 22.9 ±11.3 mmol (3 x 24h urine) (Fig B). With the exception of the 19-23h spot urine collection period, the accuracy of 3-day spot urine sampling did not significantly differ from accuracy of 1 and 3 consecutive 24h urine collections. When combining the pre-night and morning spot urine collections (19-7h), the accuracy of the estimation did not improve (ΔNa 28.7 ±19.6 mmol). Conclusion 3-day spot urine sampling did not perform significantly different than 1 and 3 24h urine collections for estimation of individual-level Na intake. Adequately powered studies need to confirm whether repeated spot urine sampling is an accurate and low burden alternative to repeated 24h urine collections.

First and second morning spot urine protein measurements for the assessment of proteinuria: a diagnostic accuracy study in kidney transplant recipients

BackgroundQuantification of proteinuria in kidney transplant recipients is important for diagnostic and prognostic purposes. Apart from correlation tests, there have been few evaluations of spot urine protein measurements in kidney transplantation.MethodsIn this cross-sectional study involving 151 transplanted patients, we investigated measures of agreement (bias and accuracy) between the estimated protein excretion rate (ePER), determined from the protein-to-creatinine ratio in the first and second morning urine, and 24-h proteinuria and studied their performance at different levels of proteinuria. Measures of agreement were reanalyzed in relation to allograft histology in 76 patients with kidney biopsies performed for cause before enrolment in the study.ResultsFor ePER in the first morning urine, percent bias ranged from 1 to 28% and accuracy (within 30% of 24-h collection) ranged from 56 to 73%. For the second morning urine, percent bias ranged from 2 to 11%, and accuracy ranged from 71 to 78%. The accuracy of ePER (within 30%) in first and second morning urine progressively increased from 56 and 71% for low-grade proteinuria (150–299 mg/day) to 60 and 74% for moderate proteinuria (300–999 mg/day), and to 73 and 78% for high-grade proteinuria (≥1000 mg/day). Measures of agreement were similar across histologic phenotypes of allograft injury.ConclusionsThe ability of ePER to accurately predict 24-h proteinuria in kidney transplant recipients is modest. However, accuracy improves with an increase in proteinuria. Given the similar accuracy of ePER measurements in first and second morning urine, second morning urine can be used to monitor protein excretion.

Visualization of user interactions with a pressure mapping mobile application for wheelchair users at risk for pressure injuries

ABSTRACT Pressure injuries for individuals with spinal cord injuries (SCI) are correlated with mortality and are a leading cause for rehospitalizations. The Assisted Weight Shift (AW-Shift©) is a mobile pressure mapping application designed to provide users with a live map view and reminders to perform weight shifts. Novel visualization techniques were used to understand daily distributions of user interaction with AW-Shift©. The date and time of system interactions were recorded for six participants with SCI over 7 days (five males/one female, five manual users/one power user, 55.3 ± 17.3 years old, 10.6 ± 6.5 years since injury). Circular frequency plots were created to visualize the time and frequency participants brought the app to the foreground of their phone and received alerts and reminders to complete weight shifts. While some participants used the system regularly throughout the day, others primarily used it before 8am; highlighting the system’s importance for regular spot checks and morning wheelchair setup. Participant adherence to weight shift reminders was low suggesting the live pressure map may be more useful. Circular frequency plots can be used by clinicians to more easily review large amounts of patient data. Future work will investigate raw pressure mat data and create a closed-loop weight shift detection algorithm.

ORTHOSTATIC BLOOD PRESSURE CHANGES AND SUBCLINICAL MARKERS OF ATHEROSCLEROSIS IN NORMOTENSIVE ADULTS. RESULTS FROM A NATIONAL-REPRESENTATIVE SURVEY

Objective: To evaluate the relationship between orthostatic upright postural blood pressure (BP) changes and subclinical markers of atherosclerosis in normotensive subjects using a simple 3-minutes standing up test. Design and method: A total of 1081 normotensive subjects enrolled in SEPHAR III national-representative survey, aged 18–80 years (42,4 ± 16.7 years, 55,3% females) underwent a simple 3 standing-up test involving BP measurement in supine position followed by BP measurements at 1 minute and 3 minutes after standing. We measured: aortic pulse wave velocity (PWVao) using a sfigmomanometric method (Arteriograph), body mass index (BMI), serum lipids, glyceated hemoglobin (HbA1c), urinary albumin-to-creatinine ratio (UACR) in morning spot urine and mean carotid intima-media thickness (IMT) by B-mode Doppler ultrasound. Orthostatic hypotension (OH) was defined by SBP decrease of at least 20mmHg and/or DBP decrease of at least 10mmHg, at 3 minutes after standing. Results: SBP and DBP increased when standing, with an average increase of SBP/DBP values when changing position of 3.7 ± 19.5 mm Hg / 9.6 ± 13.5 mm Hg at 1 minutes and 2.9 ± 19.2 mm Hg / 10.1 ± 13.2 mm Hg. Orthostatic hypotension (OH) was recoded in 130 subjects representing 12,4% of the study sample. The PWVao was significantly higher in OH subjects than in those without OH (9,12 ± 2.13m/s vs 8.08 ± 1.86m/s, p = 0,032). Stepwise regression analysis adjusted for age, sex, BMI, baseline SBP, triglycerides, HDL- cholesterol, LDL- cholesterol, fasting glucose, HbA1c, IMT, UACR and PWVao confirmed that PWVao, LDL-cholesterol and TG were independently related to orthostatic BP changes. Multiple regression analyses showed that age, baseline SBP, decrease in SBP at 3-minutes, BMI and fasting glucose were independent determinants of PWVao. Conclusions: Our results have shown that increased arterial stiffness is associated with OH during a 3- minutes standing-up test. Also, arterial stiffness may contribute to greater BP responses to postural changes from standing in normotensive subjects.

URINARY UROMODULIN DIRECTLY AND INDIRECTLY CONTRIBUTE TO LEFT VENTRICULAR HYPERTROPHY IN MIDDLE-AGED PREHYPERTENSIVES

Objective: Recent GWAS studies found uromodulin gene polymorphisms to be associated with hypertension and atrial remodeling. This study analysed urinary uromodulin (UM), sodium excretion, blood pressure (BP) and echocardiogram in a group of middle-aged non-treated subjects. Design and method: We included 326 apparently healthy subjects (mean age 37). According to JNC-7 optimal BP (OBP), prehypertension (PHT) and hypertension (HT) were diagnosed in 103 subjects (72% m), 143 subjects (43% m), and 80 subjects (38% m), respectively. Fasting blood and urine samples were obtained and office and ambulatory BP were measured in all subjects. Sodium excretion was determined from the 24h-urine specimens in a subgroup of 175 subjects. All echocardiograms were performed by the same co-author. UM an alpha1 microglobulin (A1 M) from the morning spot urine sample were determined by ELISA (Cobas Roche, BioVendor) and Siemens Dade Behring BN II Nephelometer (Siemens, Germany), and were corrected to urine creatinine, respectively. Results: Nonsignificant trend to higher nonindexed UM (nUM, mg/ml) were found in HT/PHT compared to OBP, and opposite trend was observed for indexed UM (iUM, mg/g creatinine). nUM and iUM correlated positively with ABPM parameters in OBP group, but negatively in HT. In OBP and PHT groups iUM correlated positively with fractional sodium excretion (FENa) (Rho 0.272; P = 0.01) and FENa (Rho 0.208; P = 0.02), respectively, as well as with A1mCR (Rho 0.317; P &lt; 0.001) and (Rho 0.347; P &lt; 0.001), respectively. There were significant differences in interventricular septum diameter (IVSd) between first and second/ third terciles of nUM in the OBP group (P = 0.02) and first and third terciles in the PHT group (P = 0.04). nUM correlated positively with left ventricule mass (LVM) (Rho 0.221; P = 0.01) and IVSd (Rho 0.191; P = 0.03) in the whole group. In the PHT group nUM correlated positively with IVSd (Rho 0.399; P &lt; 0.001). Conclusions: Positive association of UM with LVM suggests effect of uromodulin on left ventricule remodeling in middle-aged non-treated subjects.

URINARY UROMODULIN IS POSITIVELY ASSOCIATED WITH TOTAL CARDIOVASCULAR RISK IN MIDDLE-AGED NON-TREATED SUBJECTS WITH HIGH-NORMAL BLOOD PRESSURE

Objective: Recent studies found bidirectional association of urinary uromodulin (UM) with total cardiovascular (CV) risk. Our aim was to analyse association of urinary UM with total CV risk in a group of middle-aged non-treated subjects with high-normal blood pressure (BP). Design and method: We included 326 apparently healthy subjects (mean age 37). Fasting blood and urine samples were obtained and office and ambulatory BP were measured in all subjects. UM (morning spot urine sample) was determined by ELISA (Cobas Roche). Results: According to the JNC-7 classification, optimal BP (OBP), prehypertension (PHT) and hypertension (HT) were diagnosed in 103 subjects (72% m), 143 subjects (43% m), and 80 subjects (38% m), respectively. Based on the general cardiovascular risk algorithm 257 (78.8 %), 42 (12.9 %) and 19 (5.8%) participants were classified into the low/medium risk, high risk and very high risk groups, respectively. There were 12.9% high risk and 5% very high risk subjects in PHT, and 21% high and 16% very high risk participants in HT groups, while there weren’t high/very high risk subjects in OBP group. Nonindexed UM (nUM) was significantly lower in low/medium vs. high/very high risk groups (48.2 vs. 69/73; P = 0.003). Nonsignificant trend to the higher nUM values (mg/ml) were found in HT/PHT compared to OBP (52/56.1 vs 49.8 mg/ml). Opposite trend (43/42.9 vs. 40.6 mg/g creatinine) was observed for indexed UM (iUM). In PHT group, there were significant difference in nUM between low/medium and high/very high risk groups (50 vs. 75/77; P = 0.006). In the whole group, nUM correlated positively with total CV risk (Rho = 0.169; P = 0.003). In the PHT group, both nUM (Rho 0.32; P &lt; 0.001) and iUM (Rho 0.236; P = 0.007) correlated positively with total CV risk. Conclusions: Urinary uromodulin is positively associated with total cardiovascular risk in middle-aged non-treated prehypertensives.

Reliability of urinary charged metabolite concentrations in a large-scale cohort study using capillary electrophoresis-mass spectrometry

Currently, large-scale cohort studies for metabolome analysis have been launched globally. However, only a few studies have evaluated the reliability of urinary metabolome analysis. This study aimed to establish the reliability of urinary metabolomic profiling in cohort studies. In the Tsuruoka Metabolomics Cohort Study, 123 charged metabolites were identified and routinely quantified using capillary electrophoresis-mass spectrometry (CE-MS). We evaluated approximately 750 quality control (QC) samples and 6,720 participants’ spot urine samples. We calculated inter- and intra-batch coefficients of variation in the QC and participant samples and technical intraclass correlation coefficients (ICC). A correlation of metabolite concentrations between spot and 24-h urine samples obtained from 32 sub-cohort participants was also evaluated. The coefficient of variation (CV) was less than 20% for 87 metabolites (70.7%) and 20–30% for 19 metabolites (15.4%) in the QC samples. There was less than 20% inter-batch CV for 106 metabolites (86.2%). Most urinary metabolites would have reliability for measurement. The 96 metabolites (78.0%) was above 0.75 for the estimated ICC, and those might be useful for epidemiological analysis. Among individuals, the Pearson correlation coefficient of 24-h and spot urine was more than 70% for 59 of the 99 metabolites. These results show that the profiling of charged metabolites using CE-MS in morning spot human urine is suitable for epidemiological metabolomics studies.

VALIDITY OF FIVE FORMULAS TO ESTIMATE 24-HOUR URINARY SODIUM BY SPOT URINE SAMPLES IN ADULTS LIVING IN NORTHEAST CHINA

Objective: Although several formulas from spot urine have been used to assess 24-hour urinary sodium excretion in order to estimate salt intake, the validity in Chinese adult population is uncertain. The objective was to evaluate the accuracy of five formulas, including INTERSALT without urine potassium, Kawasaki, Tanaka, Uechi simple-mean, and a new formula, by spot urinary to predict 24-hour sodium excretion in adults living in northeast China. Design and method: This was a multi-center clinical study, conducted from April 2016 to October 2019. There were 1092 hospitalized patients aged from 18 to 85 years enrolled. Five different formulas were used to predict 24-hour urinary sodium (UNa) excretions by spot morning urinary samples. Actual urinary sodium excretion was measured from 24-hour urine samples. The estimated value is compared with the actual value by examining bias (observed minus predicted UNa), the intraclass correlation coefficients (ICC), and Bland–Altman plots. The differences between actual and estimated sodium excretion across subgroups divided by salt intake were analyzed. Results: The average excretion of sodium was 2958.15 mg/d, which is equivalent to 7.51 g/day of sodium chloride intake. Formulas produced biases for actual urinary sodium were 328.31 mg/d for INTERSALT, 517.56 mg/d for new formula, 897.59 mg/d for Tanaka, 1169.06 mg/d for Uechi, 1971.12 mg/d for Kawasaki. The correlation was positive for all equations, the highest and lowest ICC were 0.37 for new formula and 0.3 for Uechi respectively. There was no significant difference in number of patients which were beyond the mean ± 1.96 standard deviation. The least mean biases in lower salt intake subgroup (UNa no more than 2362.20 mg/d) and middle salt intake subgroup of five equations were 1283.00 mg/d and 74.46 mg/d respectively, which are calculated by INTERSALT. The least mean biases in higher salt intake subgroup (UNa more than 4724.41 mg/d) was 147.62 mg/d for Uechi. Conclusions: INTERSALT without urine potassium and new formula may offer a good performance of mean 24-h sodium estimation in lower and middle salt intake subgroups for adults living in Northeast China. The Uechi simple-mean formula performed best in higher salt intake subgroup.

Proteomic Profile of Urinary Extracellular Vesicles Identifies AGP1 as a Potential Biomarker of Primary Aldosteronism.

Primary aldosteronism (PA) represents 6% to 10% of all essential hypertension patients and is diagnosed using the aldosterone-to-renin ratio (ARR) and confirmatory studies. The complexity of PA diagnosis encourages the identification of novel PA biomarkers. Urinary extracellular vesicles (uEVs) are a potential source of biomarkers, considering that their cargo reflects the content of the parent cell. We aimed to evaluate the proteome of uEVs from PA patients and identify potential biomarker candidates for PA. Second morning spot urine was collected from healthy controls (n = 8) and PA patients (n = 7). The uEVs were isolated by ultracentrifugation and characterized. Proteomic analysis on uEVs was performed using LC-MS Orbitrap. Isolated uEVs carried extracellular vesicle markers, showed a round shape and sizes between 50 and 150 nm. The concentration of uEVs showed a direct correlation with urinary creatinine (r = 0.6357; P = 0.0128). The uEV size mean (167 ± 6 vs 183 ± 4nm) and mode (137 ± 7 vs 171 ± 11nm) was significantly smaller in PA patients than in control subjects, but similar in concentration. Proteomic analysis of uEVs from PA patients identified an upregulation of alpha-1-acid glycoprotein 1 (AGP1) in PA uEVs, which was confirmed using immunoblot. A receiver operating characteristic curve analysis showed an area under the curve of 0.92 (0.82 to 1; P = 0.0055). Proteomic and further immunoblot analyses of uEVs highlights AGP1 as potential biomarker for PA.

Urinary sodium-to-potassium ratio: a simple and useful indicator of diet quality in population-based studies

BackgroundCurrent evidence regarding the prognostic relevance of urinary sodium-to-potassium ratio (Na-to-K ratio), as an indicator of diet quality is limited. This study was conducted to investigate whether urinary Na-to-K ratio could be related to habitual dietary patterns, in a general population.MethodsThis study was conducted in the framework of the Tehran Lipid and Glucose Study (2014–2017) on 1864 adult men and women. Urinary Na and K concentrations were measured in the morning spot urine samples. Dietary intakes of the participants were assessed using a validated 147-item Food Frequency Questionnaire (FFQ) and major dietary patterns were obtained using principal component analysis. Mediterranean dietary pattern and Dietary Approaches to Stop Hypertension (DASH) score, were also calculated. Multivariable-adjusted linear regression was used to indicate association of dietary patterns and urinary Na-to-K ratio.ResultsMean (± SD) age of participants was 43.7 ± 13.9 years and 47% were men. Mean (± SD) urinary Na, K and the ratio was 139 ± 41.0 and 57.9 ± 18.6 mmol/L, 2.40 ± 0.07, respectively. Higher urinary Na-to-K ratio (> 2.37 vs. < 1.49) was related to lower intakes of vegetables (282 vs. 321 g/day), low-fat dairy (228 vs. 260 g/day) and fruits (440 vs. 370 g/day). Western dietary pattern was related to higher urinary Na-to-K ratio (β = 0.06; 95% CI 0.01, 0.16). Traditional dietary pattern, Mediterranean and DASH diet scores were inversely associated with urinary Na-to-K ratio (β = − 0.14; 95% CI − 0.24, − 0.11, β = − 0.07; 95% CI − 0.09, − 0.01, β = − 0.12; 95% CI − 0.05, − 0.02, respectively).ConclusionsSpot urinary Na-to-K ratio may be used as a simple and inexpensive method to monitor diet quality in population-based epidemiological studies.

Urine protein: Urine creatinine ratio correlation with diabetic retinopathy.

Purpose:To investigate the urine protein (UP) and urine creatinine (UC) ratio in diabetes mellitus and report its influence as a risk factor for the presence and severity of diabetic retinopathy (DR).Methods:In total, 150 diabetic patients presenting to the outpatient department were included. Detailed history with informed consent and ophthalmic examination, including visual assessment, external ocular examination, anterior segment evaluation, dilated fundus examination by slit-lamp biomicroscopy, and indirect ophthalmoscopy, was done. The early morning spot urine sample was used to determine spot urine protein creatinine ratio. Association with hypertension, fasting blood sugar (FBS), and HBA1C (glycosylated Hb) were also noted.Results:Urinary PCR increased with the severity of the diabetic retinopathy (P < 0.001). HbA1c, FBS, and duration of diabetes had a direct correlation with urine PCR. ROC curve analysis showed that the optimal PCR cut-off value for predicting the risk of onset DR was 0.65. Retinopathy progressed with increasing urine PCR. Spot urine PCR strongly correlates with stages of diabetic retinopathy and proteinuria measured in 24-h urine samples.Conclusion:The study showed that urine PCR can be a marker for risk and progression of diabetic retinopathy.

Daily Urinary Sodium Excretion Monitoring in Critical Care Setting: A Simple Method for an Early Detection of Acute Kidney Injury.

Introduction:Making an early diagnosis of acute kidney injury (AKI) is crucial. Classical biomarkers are not capable of early detection of AKI, but novel biomarkers that do have this capability are expensive and not universally available. This prospective study attempts to mitigate these limitations through the evaluation of daily urine analysis on patient admitted to a critical care unit in order to detect early AKI.Methods:Daily urinary indices were measured on every patient admitted to the intensive care unit (ICU) from the time of admission until his/her discharge from the ICU or death. This renal monitoring consisted of daily blood and spot morning urine samples in order to measure creatinine, urea, sodium, chloride and potassium in order to calculate the fractional excretion of sodium (FENa), chloride, urea and potassium. The data collected on these patients in the previous days was analyzed to determine whether or not there was a significant statistical difference in the urinary indices one day before the clinical diagnosis of AKI (day – 1) and 2 days before the diagnosis (day – 2). The statistical test applied was a single rank test, using as a limit of significance a value of P < 0.05.Results:Of the 203 patients included, 61 developed AKI. A statistical significant difference was documented only in the value of urinary sodium (UNa) and FENa between day-1 (one day before AKI clinical diagnosis) and day-2 (two days before AKI clinical diagnosis).Conclusion:Daily monitoring of UNa and FENa detected a significant change in their basal values 24 hours before clinical diagnosis of AKI was made.

The association of low-grade albuminuria with incident non-alcoholic fatty liver disease and non-invasive markers of liver fibrosis by glycaemia status.

Low-grade albuminuria, as an early marker of endothelial dysfunction and kidney damage, has been recognized as a risk factor for metabolic disorders. Epidemiological studies manifesting the association of low-grade albuminuria with the risk of incident NAFLD and fibrosis were not available. We aimed to investigate the association of low-grade albuminuria with incident NAFLD and fibrosis by glycaemia status. A prospective population-based study was performed in 3308 participants without NAFLD at recruitment. Baseline urinary albumin excretion was obtained by a first-voided early morning spot urine sample. At follow-up visit, incident NAFLD was diagnosed by hepatic ultrasound after excluding alcohol abuse and other cause of hepatic diseases. Fatty liver index (FLI) was employed to reflect liver fat content. Liver fibrosis was evaluated by NAFLD fibrosis score (NFS), fibrosis-4 score (FIB-4) and Hepamet fibrosis score (HFS) respectively. After 4.3years of follow-up, 622 (18.8%) were detected as incident NAFLD. Participants with low-grade albuminuria imposed a 40.4% [1.404 (1.112-1.772)] greater risk on incident NAFLD, and 52.0% [1.520 (1.141-2.026)], 87.4% [1.874 (1.291-2.720)] and 40.4% [1.404 (1.038-1.898)] higher risks on newly onset higher values of FLI, NFS and FIB-4 respectively. The effect of low-grade albuminuria was stronger in the subgroup of non-diabetic population. Low-grade albuminuria was independently associated with incident NAFLD and a higher probability of fibrosis, especially among non-diabetic individuals.

Validity of five formulas in estimating 24-h urinary sodium via spot urine sampling in hypertensive patients living in Northeast China.

Objective:The objective was to evaluate the accuracy of five formulas -- the Kawasaki, Tanaka, INTERSALT, Mage, and Uechi methods -- using spot urinary sampling for 24-h urinary sodium (UNa) prediction in hypertensive patients living in northeast China.Methods:There were 1154 hypertensive patients enrolled from multiple centers. Five different formulas were used to predict 24-h UNa excretion via spot morning urinary samples. Actual UNa excretion was measured from 24-h urine samples. The estimated value was compared with the actual value by examining biases, the intraclass correlation coefficients (ICC), and Bland–Altman plots.Results:The average excretion of sodium was 2.97 ± 1.26 g/day. The formula-produced mean biases for actual UNa were 0.31 g/day for INTERSALT, 0.80 g/day for Mage, 0.88 g/day for Tanaka, 1.14 g/day for Uechi, and 1.95 g/day for Kawasaki. The ICC was 0.511 for Kawasaki, 0.499 for INTERSALT, 0.468 for Tanaka, 0.402 for Mage, and 0.378 for Uechi. The least mean bias in the lower and moderate salt intake subgroups was 1.22 and 0.07 g/day, respectively, which was calculated using the Mage and INTERSALT methods. The least mean bias in the higher salt intake subgroup was 0.10 g/day for the Uechi method. The INTERSALT method was more efficiency at the individual level, with 17.4% of participants having relative differences within 10%, and 22.3% participants having absolute differences within 393 mg.Conclusion:The INTERSALT method may exhibit a good performance in estimating 24-h urinary sodium level for the hypertensive population living in northeast China.

Spot Urine Samples to Estimate Na and K Intake in Patients With Chronic Kidney Disease and Healthy Adults: A Secondary Analysis From a Controlled Feeding Study

The objective of this study was to assess the agreement between estimated 24-hour urinary sodium excretion (e24hUNa) and estimated 24-hour urinary potassium excretion (e24hUK), calculated from a spot urine sample using several available equations and actual sodium and potassium intake from a controlled diet in both healthy participants and those with chronic kidney disease (CKD). This study is a secondary analysis of a controlled feeding study in CKD patients matched to healthy controls. Participants (n=16) consumed the controlled diet, which provided ∼2400mg Na/day and ∼3000mgK/day, for 8days. On days 7 and 8, participants consumed all meals and collected all urine in an inpatient research setting, and they were discharged on day 9. The day 7 morning spot urine sample was used to calculate e24hUNa and e24hUK, which was compared with known sodium and potassium intake, respectively. Average e24hUNa from the INTERSALT and Tanaka-Na equations were higher than actual sodium intake by 373mg and 559mg, respectively, though the differences were not significant. e24hUNa from the Nerbass-SALTED equation in CKD participants was significantly higher than actual sodium intake by ∼2000mg (P<.001), though e24hUNa from the Nerbass-RRID equation was not different from intake. e24hUK from the Tanaka-K equation was significantly lower than actual potassium intake (P<.001). For both e24hUNa and e24hUK for all participants, agreement with actual intake was poor, and e24hUNa and e24hUK were not correlated with actual sodium or potassium intake, respectively. e24hUNa and e24hUK are poor indicators of true sodium and potassium intake, respectively, in both healthy and CKD participants. Findings should be confirmed in larger sample sizes with varying levels of dietary sodium and potassium.

DIABETES INDUCED MICROALBUMINURIA - A CRITICAL REVIEW

Microalbuminuria is a marker and a risk factor of diabetic renal complications commences its role in path-ogenesis of nephropathy at its third stage, the stage of incipient nephropathy. Microalbuminuria is followed by overt nephropathy and end- stage renal disease of irreversible renal damage. Early detection of microal-buminuria has a decisive role in the healthy survival of diabetics. Urine albumin excretion rate and albumin creatinine ratio on timed urine samples, early morning samples or spot urine are of beneficial use. Ayurve-da describes diabetes mellitus as Prameha roga in which the major pathogenesis takes precedence in Moot-rasaya. Microalbuminuria can be described as Prameha Janya Vrikka Roga. It occurs due to Sanga (ob-struction), Vimarga Gamana (abnormal movement) of albumin; one of the constituents of Raktadhatu (blood) through Rakta and Mootra Vaha Srotas (channels of blood and urine). Medicines which are Pramehaghna (anti-diabetic), Mootra and Raktavaha Srothosodhana (cleanse the channels) may be of good worth to rectify the pathology of microalbuminuria providing an improved life for diabetics.