Kidney damage relates to agonal bacteremia: a single-center retrospective study.

BACKGROUND: Agonal bacteremia, diagnosed with postmortem positive blood culture results, is considered a possible contributing factor to death. We hypothesized that some premortem organ damage, such as kidney damage, can enhance agonal bacteremia. METHODS: We performed a postmortem blood and alveolar fluid culture study in 30 cadavers and evaluated the relationship between blood culture results and clinical parameters, including organ damage (brain, heart, lung, kidney, liver and gastrointestinal tract). RESULTS: A total of 23 cases (76.7%) were positive for blood culture; the number of cultured species was one in 12 cases, two in 7 cases, and three in 4 cases. The ratio of agonal bacteremia was significantly higher in patients with heart damage (100%, n = 13) and those with kidney damage (end-stage kidney damage, acute kidney injury, obstructive kidney failure, or metastatic kidney tumours) (100%, n = 13). The mean number of cultured species was 0.67 ± 0.98 in heart or kidney damage, 1.40 ± 0.55 in heart damage only, 1.40 ± 0.55 in kidney damage only, and 2.00 ± 0.93 in heart and kidney damage. As the number of damaged organs increased (0 organs, no heart/kidney damage; 1 organ, heart or kidney damage; and 2 organs, heart and kidney damage), the mean number of cultured species increased significantly (p for trend = 0.001964). CONCLUSION: Premortem kidney damage relates to agonal bacteremia.

Upward-directed exit-site of the swan-neck catheter and "Easy-to-disinfect the backside area of exit-site" may prevent PD complications.

BACKGROUND: Upward-directed exit-site has been believed to be the worst for frequent ESI by an old retrospective study using straight catheters. No comparison study of 3 exit-site directions using swan-neck catheter has been performed regarding which direction is the best for our endpoints, Easy-to-see the backside area of exit-site: ESBE, Easy-to-disinfect the backside area of exit-site: EDBE, reduction of both exit-site infection (ESI), symptomatic catheter dislocation and peritonitis. METHODS: We assessed the relationship of exit-site direction with our endpoints in a quantitative cross-sectional, multicentered questionnaire survey. Patients who received either non-surgical catheter implantation or exit-site surgery were excluded. RESULTS: The numbers (percentage) of exit-site directions in included 291 patients were upward 79 (26.0), lateralward 108 (37.5) and downward 105 (36.5). Cochran-Armitage analysis showed a significant step-ladder increase in the prevalence of ESI as the direction changed from upward to lateralward to downward (0.15 ± 0.41, 0.25 ± 0.54, 0.38 ± 0.69 episodes/patient-year, p = 0.03). Multivariable regression analysis revealed the upward exit-site independently associates with both higher frequency of ESBE (OR 5.55, 95% CI 2.23-16.45, p < 0.01) and reduction of prevalence of ESI (OR 0.55, 95%CI 0.27-0.98, p = 0.04). Positive association between the prevalence of symptomatic catheter dislocation and ESI (OR 2.84, 95% CI 1.27-7.82, p = 0.01), and inverse association between EDBE and either prevalence of symptomatic catheter dislocation (OR 0.27, 95% CI 0.11-0.72) or peritonitis (OR 0.48, 95% CI 0.23-0.99) observed. CONCLUSION: Upward-directed swan-neck catheter exit-site may be the best for both ESBE and prevention of ESI. EDBE may reduce catheter dislocation and peritonitis. Symptomatic catheter dislocation may predict ESI.

Dotinurad restores exacerbated kidney dysfunction in hyperuricemic patients with chronic kidney disease.

BACKGROUND: In this study, we aimed to clarify the beneficial effects of urate-lowering treatment with the novel agent dotinurad on renal function in patients with chronic kidney disease (CKD) and hyperuricemia (HUA). METHODS: Thirty-five patients with CKD (mean age 65.4 ± 14.8 years, 23 men) diagnosed with HUA were recruited. Changes in eGFR before and after dotinurad administration were assessed. Patients first underwent a 3-month observation period and then 3 months treatment with dotinurad. RESULTS: During the observation period, mean eGFR (mL/min/1.73 m2) declined significantly. The baseline eGFR was 31.8 ± 16.4 and the serum urate level (sUA, mg/dL) was 8.1 ± 1.7. During the treatment period, eGFR recovered to 36.5 ± 17.5 and sUA decreased to 6.7 ± 1.0. The increase in eGFR after dotinurad administration was correlated with a decrease in sUA (R = 0.375, p = 0.0263). CONCLUSION: Dotinurad administration to patients with CKD and HUA appears to be beneficial in restoring kidney function. Dotinurad may represent a potential medication for the prevention of kidney function decline caused by HUA.

Lower range of serum uric acid level increases risk of rapid decline of kidney function in young and middle-aged adults: the Yuport Medical Checkup Center Study.

BACKGROUND: The effect of low serum uric acid (sUA) levels on kidney function is unclear. This study aimed to clarify the relationship between low sUA levels and the rapid decline in kidney function. METHODS: We examined the relationship between sUA levels and kidney function decline in health check-up examinees. A total of 10,547 participants were enrolled using data from the Yuport Medical Checkup Center Study between 1998 and 2002 for baseline and data from 2002 to 2006 as the follow-up period in Japan. According to sUA level (mg/dL), we classified the participants into the following six groups: (1) 2.0-2.9 (n = 247), (2) 3.0-3.9 (n = 1457), (3) 4.0-4.9 (n = 2883), (4) 5.0-5.9 (n = 2899), (5) 6.0-6.9 (n = 2010), and (6) 7.0-7.9 (n = 1,051). The relationship between sUA level and rapid decline in estimated glomerular filtration rate (ΔeGFR ≥ 3 mL/min/1.73 m2/year) was examined using a logistic regression model. RESULTS: During study period (5.4 ± 1.6 years), the incidence of rapid eGFR decline for the respective sUA groups (2.0-2.9, 3.0-3.9, 4.0-4.9, 5.0-5.9, 6.0-6.9, 7.0-7.9) were as follows: 4.5%, 4.0%, 2.4%, 3.3%, 3.1%, 3.4%. The crude and adjusted odds ratios (OR) for rapid eGFR decline were significantly higher in the 2.0-2.9 (OR:1.93 and 1.86) and 3.0-3.9 (OR:1.72 and 1.73) groups than in the 4.0-4.9 groups (reference). Stratified analysis of age differences revealed that the detrimental effect of low sUA was not evident in older adults (age ≥ 65 years). CONCLUSION: A lower normal sUA level is related to an increased risk for a rapid decline in kidney function.

Spot urine protein/creatinine ratio as a reliable estimate of 24-hour proteinuria in patients with immunoglobulin A nephropathy, but not membranous nephropathy.

BACKGROUND: Proteinuria is known to be associated with both kidney function deterioration and cardiovascular diseases. While proteinuria estimation from 24-h urine samples has traditionally been considered as the standard method for assessment of the degree of urinary protein excretion, sample collection is associated with several technical problems such as inaccurate collection and the potential spread of drug-resistant pathogens. Therefore, the spot urine protein/creatinine ratio (PCR) assessment is currently recommended as an alternative. While the utility of PCR has been validated, studies on the association between spot urine PCR and 24-h proteinuria (24HP) in patients with chronic glomerular nephritis (CGN) and nephrotic syndrome (NS) are limited. This study aimed to evaluate whether an estimated result from a spot urine PCR could sufficiently approximate the daily urine protein excretion amount from a 24-h urine sample in patients with immunoglobulin A nephropathy (IgAN), minimal change disease (MCD), and membranous nephropathy- nephrotic syndrome (MN-NS). METHODS: The study participants included 161 patients with IgAN, MCD, or MGN-NS at the Jikei University Kashiwa Hospital and Kanagawa Prefecture Shiomidai Hospital. The correlation between spot urine PCR and a 24-h urine protein was investigated using linear regression analysis with Spearman's correlation (r) coefficient and intraclass correlation coefficient (ICC). RESULTS: While high correlation coefficients (r = 0.86, P < 0.001) and substantial agreement (ICC: 0.806, P < 0.001) were observed in patients with IgAN, similar correlations were not observed in patients with MCD or MN-NS. In the patients with MCD, r was 0.53 (P < 0.001), which signified a slight correlation, and in the patients with MN-NS, r was 0.289 (P = 0.17), which was not statistically significant. CONCLUSIONS: This study revealed that spot urine PCR is a reliable estimate of 24HP value in patients with IgAN. In contrast, there is a considerable difference between the daily urine protein excretion amount based on a 24-h urine sample and that which is calculated from spot urine PCR in patients with NS.

Interventional nephrology: current status and clinical impact in Japan.

BACKGROUND: Current status and clinical significance of interventional nephrology has not been reported from Japan. METHODS: Questionnaires were mailed twice to the directors of all 534 Japanese certificated nephrology training institutions in 2014. The main questions were current performance, categorized annual procedure volume and managers of peritoneal dialysis (PD) access, vascular access (VA) surgery, endovascular intervention, and kidney biopsy. Frequencies of nephrologist involvement between high volume center and low volume center and association between the level of nephrologists' involvement to each procedure and annual procedure volume were examined. RESULTS: 332 (62.2%) institutions answered performance of all procedures and 328 (61.4%) institutions answered all procedure volume. Kidney biopsy, VA surgery, endovascular intervention and PD access surgery were performed by any doctors in 94.2, 96.3, 88.4, and 76.2% and each involvement of nephrologist was 93.9, 54.1, 53.1 and 47.6%, respectively. Cochran-Armitage analyses demonstrated significant increases in all 4 procedure volume with greater management by nephrologists (p < 0.01). Nephrologists involvement to VA surgery associated with procedure volume increase in not only VA surgery, but also PD catheter insertion (p < 0.01) and kidney biopsy (p < 0.05). And nephrologists involvement to PD catheter insertion also associated with surgical volume increase in both VA surgery (p < 0.01) and endovascular intervention (p < 0.05). CONCLUSIONS: Main manager of all 4 procedures was nephrologist in Japan. Each procedure volume increased as nephrologists become more involved. Acquisition of one specific procedure by nephrologist associated with increase not only in this specific procedure volume, but also the other procedure volume.

Measurement of daily sodium excretion in patients with chronic kidney disease; special reference to the difference between the amount measured from 24 h collected urine sample and the estimated amount from a spot urine.

It is important to grasp a patient's daily sodium intake in the management of chronic kidney disease, as sodium intake is widely recommended at 6 g/day or less. There are multiple equations widely known for estimating the daily sodium excretion from a spot urine sample, but these are aimed at healthy people. There are few reports that validate equations in patients with chronic kidney disease. The purpose of this study is to evaluate whether the amount of measured daily sodium excretion from a sample collected for 24-h urine (24HU) is equal to that of using an equation from a spot urine sample (SU) in patients with chronic kidney disease. One hundred sixty-two patients with chronic kidney disease from Kanagawa Prefecture Shiomidai Hospital, Japan and the Jikei University Kashiwa Hospital, Japan participated in the study. Daily sodium excretion was measured from 24HU and compared with it from SU by using the formula according to Tanaka et al. Sodium excretion by 24HU was 2744 mg/day and estimating daily sodium excretion from SU was 3315 mg/day. The coefficient of determination was 0.17 (p < .001) in multivariate regression analysis. The coefficient of determination was extremely low. Thus, there is a considerable difference between the amount of sodium excretion calculated from a 24HU and that from a SU in patients with chronic kidney disease.

Quantitation of Oxidative Modifications of Commercial Human Albumin for Clinical Use.

We investigated the quantitation of oxidative chemical modifications, such as thiol oxidation and carbonylation, in medical-grade human serum albumin (HSA) preparations, in comparison with those of healthy and diseased subjects. Four kinds of HSA products were obtained from three major suppliers in Japan. Eight male collegiate students and six healthy male volunteers were recruited as the young (21.6 years) and older (57.2 years) groups, respectively. Four male stable patients (64.3 years) treated with regular hemodialysis (HD) also enrolled in this study. Quantitative analyses for thiol oxidation and carbonylation were performed using HPLC and spectroscopic methods, respectively. Structural characterization was further investigated by differential scanning calorimetry (DSC) and circular dichroism (CD) spectropolarimetry. Significantly larger amounts of thiol-oxidized and carbonylated HSA products were observed than HSA obtained from healthy subjects. In the structural characterization, the midpoint temperature of the denaturation curve (Tm) analyzed by DSC was relatively high, and may have been caused by the added albumin-specific stabilizers, and CD-resolved secondary structure showed that HSA products had a helical conformation. Commercial HSA products for clinical use have a more thermally stable state and remain in a helix-rich structure, even though their specific amino acids (mainly Cys and Lys residues) are oxidatively modified.

Comparison of albuminuria test and urine test strip in Japanese hypertensive patients: AVA-E study.

BACKGROUND: Albuminuria is thought to reflect generalized endothelial dysfunction. In hypertensive patients, albuminuria is related to the risk for cardiovascular disease (CVD) events. Thus, screening for albuminuria is critical for risk stratification in hypertensive patients. However, the actual state of albuminuria in Japanese patients without diabetes remains unclear due to insurance coverage. METHODS: The CLINITEK microalb creatinine test® is a urine test paper that can assess albumin excretion corrected for urine creatinine levels in only 60 seconds without any special equipment. The semi-quantitative albuminuria test and urine proteinuria test were performed on 8,181 Japanese hypertensive patients, and the clinical significance of the test was evaluated by comparison with the urine test strip method. RESULTS: Albumin creatinine ratio (ACR) < 30 mg/g creatinine, ACR 30 - 299 mg/g creatinine, and ACR ≥ 300 mg/g creatinine on the albuminuria test were present in 70.0%, 25.7%, and 4.3%, respectively, of patients with a negative urine protein test strip result. Furthermore, in patients with a negative urine protein test strip result, ACR ≥ 30 mg/g creatinine was independently associated with previous CVD (odds ratio: 1.25, 95% confidence interval: 1.00 - 1.57, p < 0.05) after adjustment for estimated glomerular filtration rate, age, sex, BMI, smoking, dyslipidemia, diabetes, and blood pressure categories on multivariate logistic regression analysis. CONCLUSIONS: We considered that urine test strip was inadequate test to evaluate albuminuria. Easy and quick albuminuria test on the CLINITEK MICROALB CREATININE TEST might be useful test to risk stratification of hypertensive patients compared to urine test strip.

Autologous blood transfusion for hemodialysis patients: A case report and review of clinical reports and therapeutic features.

CASE REPORT: We describe a hemodialysis (HD) patient who successfully underwent total hip arthroplasty with autologous blood transfusion (ABT). There were several problems with collecting ABT in this setting. DISCUSSION: A literature search for HD patients and ABT produced 8 articles describing 29 patients. Higher doses of erythropoietin stimulating agents were used to collect ABT than for a typical HD session. In 75% of the cases autologous blood was collected just after HD to collect better quality blood. The optimal clinical procedures for ABT in HD patients need to be clarified.

Renoprotective effects of febuxostat in hyperuricemic patients with chronic kidney disease: a parallel-group, randomized, controlled trial.

BACKGROUND: Hyperuricemia is associated with the onset of chronic kidney disease (CKD) and renal disease progression. Febuxostat, a novel, non-purine, selective xanthine oxidase inhibitor, has been reported to have a stronger effect on hyperuricemia than conventional therapy with allopurinol. However, few data are available regarding the clinical effect of febuxostat in patients with CKD. METHODS: A prospective, randomized, open-label, parallel-group trial was conducted in hyperuricemic patients with stage 3 CKD. Patients were randomly assigned to treatment with febuxostat (n = 21) or to continue conventional therapy (n = 19). Treatment was continued for 12 weeks. The efficacy of febuxostat was determined by monitoring serum uric acid (UA) levels, blood pressures, renal function, and urinary protein levels. In addition, urinary liver-type fatty acid-binding protein (L-FABP), urinary albumin, urinary beta 2 microglobulin (ß2MG), and serum high sensitivity C-reactive protein were measured before and 12 weeks after febuxostat was added to the treatment. RESULTS: Febuxostat resulted in a significantly greater reduction in serum UA (-2.2 mg/dL) than conventional therapy (-0.3 mg/dL, P < 0.001). Serum creatinine and estimated glomerular filtration rate changed little during the study period in each group. However, treatment with febuxostat for 12 weeks reduced the urinary levels of L-FABP, albumin, and ß2MG, whereas the levels of these markers did not change in the control group. CONCLUSION: Febuxostat reduced serum UA levels more effectively than conventional therapy and might have a renoprotective effect in hyperuricemic patients with CKD. Further studies should clarify whether febuxostat prevents the progression of renal disease and improves the prognosis of CKD.

Comparison of predictive value for first cardiovascular event between Japanese GFR equation and coefficient-modified CKD-EPI equation.

BACKGROUND: The most superior GFR-estimating equation from the viewpoint of cardiovascular disease (CVD) prediction remains unclear. Thus, we performed cross-sectional comparison between two GFR-estimating equations (Japanese GFR equation and coefficient-modified CKD-EPI equation) and CVD incidence using Japanese nationwide "specific health checkup" data. METHODS: We recruited Japanese residents (241,159 individuals; mean 63 years; male, 38.6 %) who had not experienced CVD event (cardiac disease or stroke, or both). We calculated estimated GFR using two equations, and compared their predictive value for first symptomatic CVD event within 1 year. RESULTS: Of all subjects, the mean GFR estimated by the Japanese GFR equation (JPN-eGFR) modified for Japanese was 75.83 ± 16.18 mL/min/1.73 m(2), and that by the coefficient-modified CKD-EPI equation (mCKDEPI-eGFR) was 76.39 ± 9.61 mL/min/1.73 m(2). Area under the receiver operating characteristics curves (95 % confidence intervals) for predicting CVD event by mCKDEPI-eGFR vs. JPN-eGFR were 0.596 (0.589-0.603) vs. 0.562 (0.554-0.569). Using mCKDEPI-eGFR, the crude odds ratio (OR) for CVD incident in the 4th quartile group was far more than double (OR 2.46, 95 % CI 2.29-2.66) that in the 1st quartile group. Using JPN-eGFR, the crude OR in the 4th quartile group was less than double (OR 1.61, 95 % CI 1.51-1.73) that in the 1st quartile group. However, such superior predictive value of mCKDEPI-eGFR disappeared after adjustment for confounding factors (age, gender, BMI, presence of proteinuria, hypertension, diabetes, dyslipidemia and current smoking). CONCLUSION: GFR estimated by the coefficient-modified CKD-EPI equation was more closely related to CVD incidence than that estimated by the Japanese GFR equation. However, it is possible that low mCKDEPI-eGFR also reflects some cardiovascular risk(s) other than kidney dysfunction.

Multidisciplinary clinical strategies for encapsulating peritoneal sclerosis in peritoneal dialysis: update from Japan.

Peritoneal dialysis is established as a first-line standard renal replacement therapy for end-stage renal disease. However, the development of encapsulating peritoneal sclerosis has been a critical complication among long-term peritoneal dialysis patients. During the past decade, multidisciplinary approaches have been used to suppress encapsulating peritoneal sclerosis. The present article reviews the historical and present status of encapsulating peritoneal sclerosis in Japan.

A Case of Successfully Treated Roseomonas mucosa-induced Peritonitis Diagnosed by Mass Spectrometry.

Roseomonas mucosa is difficult to identify using routine analytical techniques. We herein report a case of peritoneal dialysis (PD)-related peritonitis caused by R. mucosa identified using matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS). A 70-year-old woman was admitted to our hospital with PD-related peritonitis. Blood agar medium of dialysate culture derived colony pale pink in color, and the organism was identified as R. mucosa using MALDI-TOF MS. She was successfully treated with ciprofloxacin and meropenem without catheter removal. To our knowledge, this is the first case of R. mucosa peritonitis in which technique failure has been avoided.

Effect of allopurinol on cardiovascular incidence among hypertensive nephropathy patients: the Gonryo study.

BACKGROUND: The present study aimed to clarify the beneficial effect of allopurinol on cardiovascular morbidity and mortality in a cohort of hypertensive nephropathy patients with impaired kidney function. METHODS: One hundred and seventy-eight patients diagnosed with hypertensive nephropathy and presenting with impaired kidney function (estimated glomerular filtration rate <45 mL/min/1.73 m(2)) were recruited from nephrology clinics. Oral allopurinol was prescribed in 67 of these patients. The effects of allopurinol use on the development of cardiovascular disease (i.e. ischemic heart disease, congestive heart failure, and stroke) and all-cause death was analyzed using the Cox proportional hazard model. RESULTS: During the follow-up of 18.4 months (mean), 28 primary events occurred. Basal use of allopurinol was a significant beneficial factor (hazard ratio = 0.342, p = 0.0434, standard error = 0.53058) after adjusting for confounding factors. CONCLUSION: The use of allopurinol in hypertensive subjects with impaired kidney function appears to be beneficial in preventing cardiovascular morbidity and all-cause mortality, indicating that this xanthine oxidase inhibitor protects the vascular system, at least in this specific group.

Anti-glomerular Basement Membrane Disease Concomitant with MPO-ANCA Positivity Concurrent with High Serum Levels of Interleukin-26 Following Coronavirus Disease 2019 Vaccination.

As coronavirus disease 2019 (COVID-19) vaccine booster campaigns progress worldwide, new reports of complications following COVID-19 vaccination have emerged. We herein report a case of new-onset anti-glomerular basement membrane (GBM) disease concomitant with myeloperoxidase-antineutrophil cytoplasmic antibody positivity concurrent with high levels of interleukin (IL)-26 following the second dose of the Pfizer-BioNTech COVID-19 vaccine. The temporal association with vaccination in this case suggests that an enhanced neutrophilic immune response through IL-26 may have triggered necrotizing glomerulonephritis and a T-cell-mediated immune response to GBMs, leading to the development of anti-GBM antibodies, with an enhanced B-cell response after the vaccination triggering anti-GBM IgG and the onset of anti-GBM disease.

Home systolic blood pressure on the morning of dialysis days has prognostic impact for hypertensive hemodialysis patients.

BACKGROUND: Hypertension is a leading cause of cardiovascular (CV) disease in the general population. Although hypertension is very common in maintenance hemodialysis (HD) patients, adequate blood pressure (BP) values and measurement timing have not been defined. METHODS: A total of 49 hypertensive HD patients were recruited. Average age was 63 ± 11 years, and duration of dialysis therapy was 6.2 ± 4.2 years. Dialysis unit BPs and various types of home BPs were separately measured, and which BPs were the most critical markers in evaluating the effect of hypertension on left ventricular hypertrophy and CV events was investigated. RESULTS: Predialysis systolic BPs were not correlated with any home BPs. Left ventricular mass index (LVMI) had a significant positive correlation with home BPs, especially morning systolic BPs on HD days (P < 0.01) and non-HD days (P < 0.05), on univariate and multivariate analysis. In contrast, predialysis BPs did not correlate with LVMI. During the follow-up period (47 ± 18 months), it was demonstrated that diabetes and home BPs, especially systolic BPs on the morning of HD days, were significant predictors of CV events on multivariate Cox regression analysis. A 10 mmHg increase in BP had a significantly elevated relative risk for CV events. CONCLUSIONS: Home BP, especially systolic BPs in the morning on HD days, can provide pivotal information for management of HD patients.

A lower level of reduced albumin induces serious cardiovascular incidence among peritoneal dialysis patients.

BACKGROUND: Human serum albumin is composed of human mercaptoalbumin (HMA) with cysteine residues having reducing powers and of oxidized human non-mercaptoalbumin. Previously, we reported that a lower HMA level is closely related to serious cardiovascular disease (CVD) incidence and mortality among hemodialysis patients. However, the relationship between HMA level and CVD incidence among peritoneal dialysis (PD) patients is unclear. METHODS: We measured the redox state of human serum albumin using high-performance liquid chromatography in 30 continuous ambulatory PD patients. The association between HMA and incidental CVD events was evaluated. RESULTS: Eight patients experienced symptomatic CVD events (5 patients died) at the 5-year follow-up. The concentration and fraction of HMA (cHMA and f(HMA), respectively) showed significantly lower values in patients with CVD than those without CVD (cHMA 1.58 ± 0.39 and 2.16 ± 0.43 g/dL, f(HMA) 48.9 ± 5.4 and 56.4 ± 8.6%, respectively). Multiple forward stepwise regression analysis using cHMA and f(HMA) as the criterion variables was performed, and C-reactive protein and hemoglobin were adopted as significant explanatory variables in the former equation, whereas urea nitrogen was adopted in the latter equation. Multiple logistic regression analysis revealed that cHMA is a statistically, and f(HMA) is a marginally significant explanatory variable of CVD incidence (p = 0.0369, R = -0.260 and p = 0.0580, R = -0.214, respectively). CONCLUSIONS: Lower HMA level, which might be caused by chronic inflammation, anemia and accumulation of dialyzable uremic toxin(s), is closely related to serious CVD incidence among PD patients.

Estimation of salt intake from spot urine samples in patients with chronic kidney disease.

BACKGROUND: High salt intake in patients with chronic kidney disease (CKD) may cause high blood pressure and increased albuminuria. Although, the estimation of salt intake is essential, there are no easy methods to estimate real salt intake. METHODS: Salt intake was assessed by determining urinary sodium excretion from the collected urine samples. Estimation of salt intake by spot urine was calculated by Tanaka's formula. The correlation between estimated and measured sodium excretion was evaluated by Pearson´s correlation coefficients. Performance of equation was estimated by median bias, interquartile range (IQR), proportion of estimates within 30% deviation of measured sodium excretion (P30) and root mean square error (RMSE).The sensitivity and specificity of estimated against measured sodium excretion were separately assessed by receiver-operating characteristic (ROC) curves. RESULTS: A total of 334 urine samples from 96 patients were examined. Mean age was 58 ± 16 years, and estimated glomerular filtration rate (eGFR) was 53 ± 27 mL/min. Among these patients, 35 had CKD stage 1 or 2, 39 had stage 3, and 22 had stage 4 or 5. Estimated sodium excretion significantly correlated with measured sodium excretion (R = 0.52, P < 0.01). There was apparent correlation in patients with eGFR <30 mL/min (R = 0.60, P < 0.01). Moreover, IQR was lower and P30 was higher in patients with eGFR < 30 mL/min. Estimated sodium excretion had high accuracy to predict measured sodium excretion, especially when the cut-off point was >170 mEq/day (AUC 0.835). CONCLUSIONS: The present study demonstrated that spot urine can be used to estimate sodium excretion, especially in patients with low eGFR.