Detection of nucleotides in hydrated ssDNA via 2D h-BN nanopore with ionic-liquid/salt-water interface.

Accomplishing slow translocation speed with high sensitivity has been the most critical mission for solid-state nanopore (SSN) device to electrically detect nucleobases in ssDNA. In this study, a method to detect nucleobases of ssDNA using a 2D SSN is introduced by considerably reducing the translocation speed and effectively increasing its sensitivity. The ultra-thin titanium dioxide coated hexagonal boron nitride nanopore was fabricated, along with an ionic-liquid 1-butyl-3-methylimidazolium hexafluorophosphate/2.0 M KCl aqueous (cis/trans) interface, for increasing both the spatial and the temporal resolutions. As the ssDNA molecules entered the nanopore, a brief surge of electrical conductivity occurred, which was followed by multiple resistive pulses from nucleobases during the translocation of ssDNA and another brief current surge flagging the exit of the molecule. The continuous detection of nucleobases using a 2D SSN device is a novel achievement: the water molecules bound to ssDNA increased the molecular conductivity and amplified electrical signals during the translocation. Along with the experiment, computational simulations using COMSOL Multiphysics are presented to explain the pivotal role of water molecules bound to ssDNA to detect nucleobases using a 2D SSN.

Risk of overhydration and low lean tissue index as measured using a body composition monitor in patients on hemodialysis: a systemic review and meta-analysis.

Overhydration and sarcopenia, related to an individual's nutritional status, have been associated with increased cardiovascular mortality and poor prognosis in patients on hemodialysis. The purpose of this study was to investigate the prediction of overhydration and sarcopenia on mortality in patients on hemodialysis using a body composition monitor. We conducted a systematic review and meta-analysis using a random-effects model. We searched the Cochrane Central Register, OVID MEDLINE, EMBASE and PubMed databases for all studies published prior to December 9, 2016 and reviewed the reference lists of relevant reviews, registered trials and relevant conference proceedings. The overhydration group (fluid excess, >15% vs. the normohydration group) and the low lean tissue index group ( <10%) were compared with a reference group. Six trials, consisting of 29,469 patients, were included in the pooled analysis. The pooled hazard ratio for overall survival of the overhydration group, compared with the reference normohydration group was 1.798 (95% confidence interval [CI]: 1.53-2.804, p = .001). The hazard ratio for mortality in the low lean tissue index group was 1.533 (95% CI, 1.411-1.644; p = .001) in the random-effects model. The results from the most recent study showed the greatest heterogeneity in the sensitivity analysis. Low lean tissue index and overhydration, measured using a body composition monitor, were associated with a high mortality rate in patients on hemodialysis.

New method of predicting dry weight using bioelectrical impedance analysis in haemodialysis patients.

AIM: There were significant differences in the slopes of the ultrafiltration (UF) amount removed during haemodialysis (HD) sessions versus the percentage change in the extracellular fluid/total body water ratio for the right lower extremity (ECF/TBW(right leg)) plot in normohydrated (NH) and overhydrated states. The purpose of this study was to develop and validate a method for predicting dry weight (DW) using these results. METHODS: It was hypothesized that for patients to become NH, the slope of the UF amount versus the percentage changes in ECF/TBW(right leg) plot should be same as that of NH patients and a method for predicting DW was developed. To validate the accuracy of this method, the ECF/TBW(right leg) was measured by eight-point tactile-electrode bioelectrical impedance analysis before and after HD in 17 newly enrolled NH patients. Using the current DW (cDW) of subjects as a reference, we compared the accuracies of pDW1 (our devised method) and pDW2 (the normovolaemia/hypervolaemia slope method). RESULTS: The mean cDW, pDW1 and pDW2 values were 56.8 +/- 7.9, 56.4 +/- 7.7 and 56.3 +/- 8.0 kg, respectively. No significant differences existed between cDW, pDW1 and pDW2. pDW1 had a lower root mean square error than pDW2 (1.12 vs 1.69). On the Bland-Altman plot, differences between pDW1 and cDW were closer to zero than between pDW2 and cDW. CONCLUSION: A new method was developed of predicting the DW using the relationship between the UF amount and the percentage change in the ECF/TBW ratio of the lower extremities after HD. The devised method appears to be as accurate as the normovolaemia/hypervolaemia slope method.

Different pattern of fluid loss from the lower extremities in normohydrated and overhydrated stage 5 chronic-kidney-disease patients after haemodialysis.

AIM: It is unclear whether fluid is lost from each body segment in a similar manner during haemodialysis (HD) in normohydrated (NH) and overhydrated (OH) patients. METHODS: The authors measured changes in regional-body fluid compartments using segmental multifrequency bioelectrical impedance analysis before and after HD in 26 stage 5 chronic-kidney-disease patients. Patients were divided into NH and OH groups. Correlation between ultrafiltration (UF) amount and per cent changes in extracellular fluid (ECF)/total body water (TBW) ratios measured in five body segments were analysed in NH and OH groups. RESULTS: No differences were found between the two groups with respect to per cent decreases in body weight, TBW, or intracellular fluid levels. Correlation coefficients between UF amounts and per cent decreases in TBW, intracellular fluid and ECF were higher in the NH group than in the OH group. UF amounts were found to be correlated with per cent ECF/TBW decreases in all body segments in the NH group but, to be only correlated with per cent decreases in ECF/TBW(Left arm) and ECF/TBW(Trunk) in the OH group. Positive correlations were found between UF amounts and per cent ECF/TBW(Right leg) decreases (r = 0.66, P = 0.01), regardless of age in the NH group only. CONCLUSION: NH and OH patients show different patterns of fluid loss from regional-body fluid compartments. This may be useful for determining patient hydration status.

Agreements between indirect calorimetry and prediction equations of resting energy expenditure in end-stage renal disease patients on continuous ambulatory peritoneal dialysis.

PURPOSE: Equations are frequently used to estimate resting energy expenditure (REE) in a clinical setting. However, few studies have examined their accuracy in end-stage renal disease (ESRD) patients. PATIENTS AND METHODS: To investigate agreement between indirect calorimetry and several REE estimating equations in 38 ESRD patients on peritoneal dialysis, we performed indirect calorimetry and compared the results with REEs estimated using 5 equations [Harris-Benedict (HBE), Mifflin, WHO, Schofield, and Cunningham]. RESULTS: Measured REE was 1393.2+/-238.7 kcal/day. There were no significant differences between measured and estimated REEs except Mifflin (1264.9+/-224.8 kcal/day). Root mean square errors were smallest for HBE, followed by Schofield, Cunningham, and WHO, and largest for Mifflin (171.3, 171.9, 174.6, 175.3, and 224.6, respectively). In Bland-Altman plot, correlation coefficients between mean values and differences were significant for HBE (r=0.412, p=0.012) and tended to be significant for Cunningham (r=0.283, p=0.086). In DM patients and patients with overhydration, HBE showed significant underestimation when REE increased. CONCLUSION: In ESRD patients on continuous ambulatory peritoneal dialysis (CAPD), REE-estimating equations have no significant differences from indirect calorimetry, except Mifflin. However, HBE showed greater bias than others when REE was high.

Comparison of ultrasound scan blood flow measurement versus other forms of surveillance in the thrombosis rate of hemodialysis access: A systemic review and meta-analysis.

BACKGROUND: The benefit of access flow surveillance in preventing vascular access thrombosis and failure remains controversial, as many randomized clinical trials (RCTs) have failed to demonstrate consistent results. The aim of this study was to perform a meta-analysis including newly published RCTs with a subgroup analysis for arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs). METHODS: A systematic review of the available literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. An electronic search was conducted using the MEDLINE, EMBASE, and Cochrane Library databases of RCTs conducted from 1970 to 2017 that involved access flow surveillance. As a result, 9 RCTs met our criteria. The control group was defined by indirect and various surveillance methods such as dynamic venous pressure measurement and physical examination. Conversely, the interventional group was defined as a noninvasive duplex ultrasound scan (USS) or ultrasound dilution that directly measured the flow of vascular access. RESULTS: The studies included 990 patients comprising 658 native AVFs and 332 AVGs. The prevalence of diabetes was 29.3%and 30.5% in the interventional and control groups, respectively. The estimated overall pooled risk ratio (RR) of thrombosis was 0.782 [95% confidence interval (95% CI), 0.553-1.107; P = .17], favoring interventional group, although this was not statistically significant. In the subgroup analysis, the pooled RR of thrombosis was .562 (95% CI, 0.346-0.915; P = .02) for AVFs, which significantly favored the interventional group. Conversely, the pooled RR for AVGs was 1.104 (95% CI, 0.672-1.816; P = .70). CONCLUSION: The surveillance method to measure access flow through USS showed a significant benefit for reducing thrombosis in AVFs. The result encourages adherence to the current guidelines for AVFs. However, no benefit was found regarding AVGs. Recent guidelines with a "one-size-fits-all" approach may be revised to a "tailored-to-risk" approach.

Unusual Case of Posterior Reversible Encephalopathy Syndrome in a Patient with Anti-glomerular Basement Membrane Antibody Glomerulonephritis: A Case Report and Review of the Literature.

Posterior reversible encephalopathy syndrome (PRES) is characterized by a clinical and radiological entity with the sudden onset of seizures, headache, altered consciousness, and visual disturbances in patients with the findings of reversible vasogenic subcortical edema without infarction. Hypertension, renal disease, and autoimmune disease are co-morbid conditions of PRES. Nevertheless, there have only been a few case reports of PRES in a patient with anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN). This paper presents the possible first Korean case of a 36-year-old woman with the striking features of PRES. She presented with a sudden onset of visual blindness, headache, and seizure. The brain MRI images revealed hyperintense lesions in both the occipital and parietal lobes, which suggested vasogenic edema. Three months before this presentation, she was diagnosed with anti-GBM GN. Since then, she underwent immunosuppression with cyclophosphamide and steroid, and hemodialysis for renal failure with a treatment of anti-GBM GN.

Superior patient survival for continuous ambulatory peritoneal dialysis patients treated with a peritoneal dialysis fluid with neutral pH and low glucose degradation product concentration (Balance).

BACKGROUND: In recent years, laboratory and clinical research has suggested the need for peritoneal dialysis fluids (PDFs) that are more biocompatible than the conventional PDFs commonly used today. Bioincompatibility of PDF has been attributed to low pH, lactate, glucose, glucose degradation products (GDPs), and osmolality. PDFs with neutral pH and low GDPs are now available commercially. In vitro and early clinical studies suggest that these solutions are indeed more biocompatible but, as of now, there is no evidence that their use improves patient outcome. METHODS: Using a dedicated database of over 2000 patients treated with PD in Korea, we were able to conduct a retrospective observational study comparing outcomes for incident continuous ambulatory PD patients treated with a standard, conventional, heat-sterilized PDF to the outcomes for patients treated with a novel, low GDP, neutral-pH PDF prepared in a dual-compartment, double-bag PD system (Balance; Fresenius Medical Care, St. Wendel, Germany). In an intention-to-treat analysis, patient and technique survival, peritonitis-free survival, and peritonitis rates were compared in 611 patients treated with Balance for up to 30 months and 551 patients with a standard PDF (stay . safe; Fresenius Medical Care) treated in the same era and with equivalent follow-up. RESULTS: The patients were well matched for most relevant characteristics except older age distribution for the patients treated with the standard PDF. Patients treated with Balance had significantly superior survival compared to those treated with the standard PDF (74% vs 62% at 28 months, p = 0.0032). In a multivariate Cox regression model including age, diabetes, and gender, the survival advantage persisted (relative risk of death for Balance 0.75, 95% confidence interval 0.56 - 0.99, p = 0.0465). Modality technique survival was similarin Kaplan-Meieranalysis for both PDFs. No differences were detected in peritonitis-free survival or in peritonitis rates between the two solutions. CONCLUSION: This study, for the first time, suggests that treatment with a novel biocompatible PDF with low GDP concentration and neutral pH confers a significant survival advantage. The exact mechanisms for such a survival advantage cannot be determined from this study. The usual criticisms of observational studies apply and the results reported here strongly warrant the undertaking of appropriately designed, randomized, controlled clinical trials.

Comparison of anthropometric data between end-stage renal disease patients undergoing hemodialysis and healthy adults in Korea.

Protein-calorie malnutrition is prevalent in hemodialysis (HD) patients. The prevalence of obesity in healthy Korean adults has increased rapidly during the last 10 years. However, there are few large scale data collections available about the current weight status of Korean HD patients. The weight statuses of 10,304 HD patients (data from the Insan Memorial Dialysis Registry 2002, Korean Society of Nephrology) were compared to those of 12,436 control subjects (age > 18) by using body mass index (BMI). Weight status was assessed by WHO classification for Asian-Pacific region [underweight (UW): < 18.5; normal weight (NW): 18.5-22.9; overweight (OW): 23-24.9; obese (OB): 25-29.9; and extremely obese (EOB): > 30 kg/m2] in both the control and HD patients. HD patients had significantly lower body weight and BMI than the controls in all age groups and in both sexes. For the male controls, the proportions of OW and OB showed a reversed U-shape, peaking at the 5th and 6th decades. of the numbers of those classified as NW and UW were relatively small. For the female controls, the proportions of OW and OB progressively increased with age. On the contrary, in HD patients, the proportions of NW and UW were large, up to more than 70%, and those of OW and OB were small in both sexes. In each age group, UW was seen significantly more in the HD group than in the control group. The 6th decade age group showed the highest prevalence ratio for UW in the HD group for both sexes, compared to the controls (Male: 17.33, Female: 17.68). The percentages of UW were related to HD duration and age in both sexes. In conclusion, Korean HD patients seem to have small proportions of OW and OB, compared to the general population, and protein-calorie malnutrition may still be an important nutritional condition.

Abdominal Obesity and Mortality in Continuous Ambulatory Peritoneal Dialysis Patients.

BACKGROUND: The relationship between abdominal obesity (AO) and mortality in peritoneal dialysis (PD) patients is controversial. METHODS: The prevalence of AO in 84 PD patients was assessed in a cross-section manner and followed up for 9 years at a single center. AO was defined as a waist circumference (WC) of more than 90 cm in males or more than 80 cm in females. The patients were classified as either with AO(AO group) or without AO(nAO group). RESULTS: The AO group was older, contained more diabetics, more females, and had higher Charlson comorbidity index (aCCI) scores, BMI, and triglyceride and lower serum creatinine than the non-AO subjects. The follow-up duration was 53.2±34.4 months. At the end of the follow-up, eighteen patients (21.4%) were dead; 9 died of cardiovascular causes. The five year survival rate was 40.8%. Kaplan-Meier analysis revealed that both all-cause and cardiovascular-cause mortalities were similar in the AO and nAO groups. Multivariate analysis revealed the presence of AO not to be an independent risk factor of all-cause and cardiovascular-cause mortality. CONCLUSION: AO itself might not be a risk factor for mortality in PD patients. Nevertheless, further prospective studies with a large number of patients will be needed to prove this.

Plasma brain natriuretic peptide concentration on assessment of hydration status in hemodialysis patient.

BACKGROUND: Brain natriuretic peptide (BNP) is released into circulation in response to ventricular dilatation and pressure overload. Plasma BNP concentration correlates with left ventricular mass and dysfunction, which is prevalent in hemodialysis (HD) patients. METHODS: To evaluate the potential of BNP level for determination of hydration status, we measured inferior vena caval diameter (IVCD) and BNP levels and performed bioimpedance analysis in 49 HD patients. RESULTS: Pre-HD BNP levels remained unchanged after HD. Agreement between IVCD and pre-HD BNP level in overhydration was significant (kappa = 0.304). The area under the receiver operating characteristic (ROC) curve for overhydration was 0.819 for pre-HD BNP level. When extracellular fluid/total-body water (ECF/TBW) ratios of HD patients were compared with those of 723 controls, pre- and post-HD BNP levels were significantly greater in overhydrated patients. The area under the ROC curve for overhydration by ECF/TBW ratio was 0.781 for pre-HD BNP level. However, there was no significance for pre- or post-HD BNP levels on assessment of normohydration or underhydration. Pre-HD BNP level correlated significantly with post-HD BNP level, post-HD diastolic blood pressure, pulse pressure, and ECF/TBW ratio. IVCD correlated significantly with post-HD BNP level. CONCLUSION: BNP level seems to have a limited potential for assessment of overhydration in HD patients.

Time-averaged concentration of dialysate sodium relates with sodium load and interdialytic weight gain during sodium-profiling hemodialysis.

BACKGROUND: Factors determining sodium level during sodium-profiling hemodialysis rarely have been studied. We hypothesized that the time-averaged concentration of dialysate sodium (TAC(Na)) is related to intradialytic sodium load and interdialytic complications. METHODS: Eleven patients underwent 6-week periods of (1) conventional hemodialysis with a dialysate sodium concentration of 138 mmol/L (TAC(138)) and (2) sodium-profiling hemodialysis with a dialysate sodium concentration of 150 to 138 mmol/L (TAC(Na), 140 mmol/L [TAC(140)]) and (3) 155 to 130 mmol/L (TAC(Na), 147 mmol/L [TAC(147)]). Serum sodium level, weight gain, 24-hour blood pressure, and intradialytic and interdialytic discomfort were compared. RESULTS: Serum sodium levels increased during the TAC(140) and TAC(147) periods (P < 0.05 compared with predialysis serum sodium). Intradialytic change in sodium level correlated positively with TAC(Na) (r = 0.945; P < 0.001). Regression analysis indicates that positive sodium load occurred with TAC(Na) more than 137.8 mmol/L. Interdialytic weight gain increased in proportion to TAC(Na) (P < 0.05 compared with each other period), with a positive correlation (r = 0.823; P < 0.001). TAC(Na) causing interdialytic weight gain less than 3 kg was estimated to be less than 143.5 mmol/L. Intradialytic hypotension decreased, but interdialytic discomforts increased during the TAC(147) period (P < 0.05 compared with TAC(138) and TAC(140)). Mean 24-hour blood pressures and pressure loads increased during the TAC(147) period (P < 0.05 compared with TAC(138) and TAC(140)). Mean diastolic blood pressure correlated positively with TAC(Na) (r = 0.354; P < 0.05). CONCLUSION: TAC(Na) is a factor determining sodium load and interdialytic complications during sodium-profiling hemodialysis. Defining the optimal TAC(Na) for individual centers based on their protocols will be helpful to avoid sodium load and excessive weight gain.

Normal values of total body water in healthy Korean adults: comparison with data from western populations.

To find reference total body water (TBW) values in healthy Korean adults, we performed single frequency bioelectrical impedance analysis on 2942 healthy adults and compared these data with those of normal western adults. Males were found to have greater TBW than females. Conversely, females were found to have greater percent fat (pFat) than males. In both sexes, body weight (BW) and TBW were significantly lower in age groups of < 30, 50 - 59, > or = 60 years than in the 40 - 49 years age group. pFats were significantly higher in age groups of 50 - 59 and > or = 60 years than in the 40 - 49 years age group. pFats were similar among age groups of < 30, 30 - 39, and 40 - 49 in both sexes. In all age groups, pFats were significantly higher in females than in males. TBW was significantly correlated with BW, height (HT), fat mass, and body mass index (BMI) in both sexes. There was a significant correlation between TBW and age in males(r=-0.15, p=0.00), but not in females (r=-0.02, p=0.45). On linear regression analysis, TBW values were independently associated with BW, HT and age in males and were independently associated with BW and BMI in females. In all age groups, Korean males and females had lower mean TBW than in Western populations. However, this difference was greater in males than in females. In summary, we represented the contemporary normal TBW data in healthy Korean adults. At present, there are no national reference data relating TBW in Korea. We hope the results of this study will be useful as the baseline data for the evaluation of hydration and nutritional status in healthy and ill adults, including end-stage renal disease (ESRD).

Additive antiproteinuric effect of combination therapy with ACE inhibitor and angiotensin II receptor antagonist: differential short-term response between IgA nephropathy and diabetic nephropathy.

In previous studies, the synergistic antiproteinuric effect of the combination therapy of ACE inhibitors and angiotensin II receptor antagonists (ATRAs) has been inconsistent in relation to underlying renal diseases. The influence from the blood pressure (BP) - reducing effect in some studies might also contribute to this inconclusiveness. To examine the possibility of the benefit being different according to underlying renal diseases, we undertook a crossover therapeutic trial of the combination therapy in two selected homogenous groups of patients with diabetic and non-diabetic renal diseases. The BP-reducing effect was excluded during the study. Nineteen biopsy-proven IgA nephropathy, as examples of non-diabetic renal diseases, and 24 type 2 diabetic nephropathy patients were selected as the study subjects. The subjects had to meet the follow criteria: a creatinine clearance (Ccr) between 25 - 90 ml/min/1.73 m2, 24-hr urinary protein excretion rate over 1.0 g/day and a BP maintained at less than 130/80 mmHg, with more than six-month therapy of ramipril, (5.7 +/- 0.4 mg/day, 13 +/- 2 month). The baseline data between the two groups showed no significantly differences. After a 12-week stabilization period (control period), 4 mg, once daily, dose of candesartan (combination period) followed by a placebo (placebo period), or vice versa, were administered in addition to the ramipril, for 12 weeks. The combination, with candesartan, did not change the Ccr, BP, serum and urinary electrolytes or the urea. The 24 hour urinary protein excretion rate was significantly reduced by the combination therapy in the patients with IgA nephropathy (3.1 +/- 0.3 g/day in combination, 4.2 +/- 0.3 in control, and 4.3 +/- 0.2 in placebo; p < 0.05). However, the patients with diabetic nephropathy showed no reduction in their proteinuria with the combination therapy (3.8 +/- 0.2 g/day in combination, 3.9 +/- 0.3 in control, and 4.1 +/- 0.3 in placebo; p=NS). The changes in proteinuria showed no relationship with the changes in the BP in IgA nephropathy. In conclusions, the benefit of combination therapy of its antiproteinuric effect was different between IgA and diabetic nephropathy over the 12-week trial. The difference in the pathophysiological role, and the importance of the renin- angiotensin system, between the two diseases might contribute to the discrepancy in the result. We suggest the discrimination of the underlying renal diseases in the study subjects is an important prerequisite for future studies on this issue.

Acute renal failure associated with a minimal change nephrotic syndrome in a systemic lupus erythematosus patient.

In systemic lupus erythematosus (SLE), acute renal failure (ARF) is usually associated with severe lupus nephritis and ARF associated with other glomerular diseases is extremely rare. We recently encountered a patient with ARF that was associated with a minimal change nephrotic syndrome (MCNS) in SLE. A 41-year-old woman presented with a nephrotic syndrome and ARF. She fulfilled four of the American College of Rheumatology criteria for the classification of SLE. However, a renal biopsy revealed that there were no glomerular abnormalities and no deposition of immune complex. The generalized edema disappeared and the high creatinine levels decreased after prednisolone therapy.

The association between mortality and abdominal aortic calcification and relation between its progression and serum calcium concentration in chronic hemodialysis patients.

BACKGROUND: The composite summary score (range, 0-24) of abdominal aortic calcification (AAC) devised by Kauppila et al is a simple method of assessing AAC severity. However, few studies have been conducted to determine an optimal AAC cutoff score for the prediction of mortality or to investigate the relation between mineral metabolism and AAC progression using the scoring system. METHODS: The medical records of 112 patients on hemodialysis who had undergone simple lateral lumbar radiography every 6 months from August 2009 were reviewed. Patients were followed until November 2012, and the relationship between the degree of AAC at baseline and mortality was evaluated. In addition, the relationship between the progression of AAC and serum concentrations of calcium and phosphate was evaluated in the 75 patients who were successfully followed until November 2012. RESULTS: The mean AAC score at baseline was 5.5±4.8, and the cutoff calcification score for the prediction of mortality was 7.75 (sensitivity=61%, specificity=81%). Patients were allocated to Group A (baseline total calcification score ≤8.0, n=85) or Group B (baseline total calcification score>8.0, n=27), and multivariate analysis showed that Group B was an independent risk factor of all-cause mortality and cardiovascular events. Of the 75 patients successfully followed, 51 showed AAC progression (Group 1) and 24 showed no change or improvement (Group 2). Group 1 was found to have significantly higher mean serum corrected calcium levels during the 2(nd) year and 3(rd) year of follow-up than Group 2. Furthermore, repeated-measures analysis of variance showed higher monthly corrected calcium concentrations (P=0.099) and mean corrected calcium levels during the 1(st) year, 2(nd) year, and 3(rd) year of follow-up (P=0.062) in Group 1, but without statistical significance. The cutoff values of mean corrected calcium of the 2(nd) year and 3(rd) year for the prediction of AAC progression during follow-up years were 8.96 mg/dL and 9.45 mg/dL, respectively. Serum phosphate levels and corrected calcium×phosphate values were similar in Groups 1 and 2. CONCLUSION: Patients with an AAC score of>8 at baseline seem to be at higher risk of mortality during follow-up. Of the serum variables examined, such as corrected calcium, phosphate, and corrected calcium×phosphate, corrected calcium was found to be marginally associated with AAC progression. However, a larger-scale prospective study is required to confirm our findings.

Effect of dialysate sodium concentration on sodium gradient and hemodialysis parameters.

This retrospective study was performed to determine the ranges of the sodium gradient (SG) between the dialysate sodium concentration (DNa) and serum sodium concentration (SNa) in hemodialysis (HD) patients and to examine the relationships between HD parameters over a 1 year period. Fifty-five clinically stable HD patients, who had been on HD >2 years were enrolled. Monthly HD [ultrafiltration (UF) amount, systolic blood pressure (SBP), frequency of intradialytic hypotension (IDH)] and laboratory data were collected and 12-month means were subjected to analysis. The SG was calculated by subtracting SNa from prescribed DNa. Mean SG values were 1.5±3.3 (range -5.6~9.1). SG was positively related to DNa and the frequency of IDH. A higher SG was associated with larger UF amounts and SBP reduction during HD. The percentages of patients with a SG ≥3mEq/L increased as DNa increased. On the other hand, SG was not found to be associated with SNa or pre-HD SBP. DNa appears to cause a significant increase in SG, and this seems to be related to HD parameters, such as, UF amount and IDH.

A Case of Post-radiotherapy Urethral Stricture with Spontaneous Bladder Rupture, Mimicking Obstructive Uropathy due to Cancer Metastasis.

Non-traumatic, spontaneous urinary bladder rupture is a rare complication of urethral stricture. Furthermore, its symptoms are often nonspecific, and misdiagnosis is common. The authors experienced a case of urethral stricture with spontaneous bladder rupture and bilateral hydronephrosis, mimicking obstructive uropathy attributed to cancer metastasis. A 55-year-old woman was admitted with abdominal pain and distension, oliguria, and an elevated serum creatinine level. She had undergone radical hysterectomy for uterine cervical cancer and received post-operative concurrent chemoradiation therapy 13 years previously. Non-contrast enhanced computed tomography showed massive ascites and bilateral hydronephrosis. The initial diagnosis was acute kidney injury due to obstructive uropathy caused by malignant disease. After improvement of her renal function by bilateral percutaneous nephrostomy catheterization, contrast-enhanced computed tomography and a cytologic examination of ascites showed no evidence of malignancy. However, during retrograde pyelography, a severe urethral stricture was found, and subsequent cystography showed leakage of contrast into the peritoneal cavity and cystoscopy revealed a defect of the posterior bladder wall. After urethral dilatation and primary closure of the bladder wall, acute kidney injury and ascites were resolved.

Successful antibiotic treatment of Pseudomonas stutzeri-induced peritonitis without peritoneal dialysis catheter removal in continuous ambulatory peritoneal dialysis.

Pseudomonas stutzeri is a Gram-negative, rod-shaped, motile, single polar-flagellated, soil bacterium that was first isolated from human spinal fluid and is widely distributed in the environment. It was isolated as an uncommon opportunistic pathogen from humans, and a few cases of P. stutzeri-induced peritonitis have been reported in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Catheter removal with antibiotic treatment is generally recommended because peritonitis by Pseudomonas species is commonly associated with catheter-related infection. Here, we describe the first case of P. stutzeri-induced peritonitis in an 82-year-old woman in Korea. She had received two antipseudomonal antibiotics, an aminoglycoside (isepamicin, Yuhan corporation, Seoul, Korea) and a fluoroquinolone (ciprofloxacin), and was successfully treated without removal of the CAPD catheter.

A case of biopsy-proven chronic kidney disease on progression from acute phosphate nephropathy.

Acute phosphate nephropathy (APhN) following oral sodium phosphate solution (OSP) ingestion as a bowel purgative has been frequently reported. It was recently suggested that APhN could progress to chronic kidney disease (CKD) and a history of APhN might be considered as one of the causes of CKD. However, there are few reports proving APhN as a cause of CKD. Here, we report a case of APhN that progressed to CKD, as proven by renal biopsy.