The number of patients with end-stage renal disease (ESRD) has rapidly increased, as has the cost of dialysis. Peritoneal dialysis (PD) is an established treatment for ESRD patients worldwide; it has a variety of advantages, including autonomy and flexibility, as well as economic benefits in many countries compared to hemodialysis (HD). However, the long-term survival rate of PD remains poor. Although direct comparison of survival rate between the dialysis modalities by randomized controlled trials is difficult due to the ethical issues, it has always been a crucial point when deciding which dialysis modality should be recommended to patients. Recently, in many countries, including the United States, Brazil, Spain, Australia, and New Zealand, the survival rate in PD patients has significantly improved. PD patient survival in Korea has also improved, but Korean PD patients are known to have higher risk of mortality and major adverse cardiovascular, cerebrovascular events than HD patients. Herein, we further evaluate why Korean PD patients had worse outcomes; we suggest that special attention should be paid to patients with diabetes, coronary artery disease, or congestive heart failure when they choose PD as the first dialysis modality in order to reduce mortality risk.
Australia ; Brazil ; Cardiovascular Diseases ; Coronary Artery Disease ; Dialysis* ; Ethics ; Heart Failure ; Humans ; Kidney Failure, Chronic ; Korea ; Mortality ; New Zealand ; Peritoneal Dialysis* ; Pliability ; Renal Dialysis ; Spain ; Survival Rate ; United States

The electrogenic sodium/bicarbonate cotransporter 1 (NBCe1) on the basolateral side of the renal proximal tubule plays a pivotal role in systemic acid-base homeostasis. Mutations in the gene encoding NBCe1 cause severe proximal renal tubular acidosis accompanied by other extrarenal symptoms. The proximal tubule reabsorbs most of the sodium filtered in the glomerulus, contributing to the regulation of plasma volume and blood pressure. NBCe1 and other sodium transporters in the proximal tubule are regulated by hormones, such as angiotensin II and insulin. Angiotensin II is probably the most important stimulator of sodium reabsorption. Proximal tubule AT(1A) receptor is crucial for the systemic pressor effect of angiotensin II. In rodents and rabbits, the effect on proximal tubule NBCe1 is biphasic; at low concentration, angiotensin II stimulates NBCe1 via PKC/cAMP/ERK, whereas at high concentration, it inhibits NBCe1 via NO/cGMP/cGKII. In contrast, in human proximal tubule, angiotensin II has a dose-dependent monophasic stimulatory effect via NO/cGMP/ERK. Insulin stimulates the proximal tubule sodium transport, which is IRS2-dependent. We found that in insulin resistance and overt diabetic nephropathy, stimulatory effect of insulin on proximal tubule transport was preserved. Our results suggest that the preserved stimulation of the proximal tubule enhances sodium reabsorption, contributing to the pathogenesis of hypertension with metabolic syndrome. We describe recent findings regarding the role of proximal tubule transport in the regulation of blood pressure, focusing on the effects of angiotensin II and insulin.
Acidosis, Renal Tubular ; Angiotensin II ; Blood Pressure* ; Diabetic Nephropathies ; Homeostasis ; Humans ; Hypertension ; Insulin ; Insulin Resistance ; Kidney Tubules, Proximal ; Plasma Volume ; Rabbits ; Rodentia ; Sodium ; Sodium-Bicarbonate Symporters

The concept of big data, commonly characterized by volume, variety, velocity, and veracity, goes far beyond the data type and includes the aspects of data analysis, such as hypothesis-generating, rather than hypothesis-testing. Big data focuses on temporal stability of the association, rather than on causal relationship and underlying probability distribution assumptions are frequently not required. Medical big data as material to be analyzed has various features that are not only distinct from big data of other disciplines, but also distinct from traditional clinical epidemiology. Big data technology has many areas of application in healthcare, such as predictive modeling and clinical decision support, disease or safety surveillance, public health, and research. Big data analytics frequently exploits analytic methods developed in data mining, including classification, clustering, and regression. Medical big data analyses are complicated by many technical issues, such as missing values, curse of dimensionality, and bias control, and share the inherent limitations of observation study, namely the inability to test causality resulting from residual confounding and reverse causation. Recently, propensity score analysis and instrumental variable analysis have been introduced to overcome these limitations, and they have accomplished a great deal. Many challenges, such as the absence of evidence of practical benefits of big data, methodological issues including legal and ethical issues, and clinical integration and utility issues, must be overcome to realize the promise of medical big data as the fuel of a continuous learning healthcare system that will improve patient outcome and reduce waste in areas including nephrology.
Bias (Epidemiology) ; Classification ; Data Mining ; Decision Support Systems, Clinical ; Delivery of Health Care ; Epidemiology ; Ethics ; Humans ; Learning ; Nephrology ; Propensity Score ; Public Health Surveillance ; Statistics as Topic

No abstract available.
Kidney Diseases* ; Kidney* ; Obesity*

Administration of autologous mesenchymal stem cells (MSCs) has been shown to improve renal function and histological findings in acute kidney injury (AKI) models. However, its effects in chronic kidney disease (CKD) are unclear, particularly in the clinical setting. Here, we report our experience with a CKD patient who was treated by intravenous infusion of autologous MSCs derived from adipose tissue in an unknown clinic outside of Korea. The renal function of the patient had been stable for several years before MSC administration. One week after the autologous MSC infusion, the preexisting renal insufficiency was rapidly aggravated without any other evidence of AKI. Hemodialysis was started 3 months after MSC administration. Renal biopsy findings at dialysis showed severe interstitial fibrosis and inflammatory cell infiltration, with a few cells expressing CD34 and CD117, 2 surface markers of stem cells. This case highlights the potential nephrotoxicity of autologous MSC therapy in CKD patients.
Acute Kidney Injury ; Adipose Tissue ; Biopsy ; Dialysis ; Fibrosis ; Humans ; Infusions, Intravenous ; Korea ; Mesenchymal Stromal Cells* ; Renal Dialysis ; Renal Insufficiency* ; Renal Insufficiency, Chronic ; Stem Cells ; Transplantation, Autologous

BACKGROUND: Plasmapheresis has become an essential element of kidney transplantation (KT). In the present study, we report clinical outcomes of filtration plasmapheresis using continuous renal replacement therapy machines with a single filter for the first time in Korea. METHODS: We retrospectively analyzed six patients who underwent filtration plasmapheresis for KT in our center; plasmapheresis was performed using the Plasmaflex (Baxter®) with a TPE 2000 filter set (Baxter®) in our hemodialysis unit. Five percent albumin was used as the replacement fluid, and intravenous immunoglobulin G was administered after each plasmapheresis session. The target preoperative ABO isoagglutinin titer was less than 1:8. RESULTS: Filtration plasmapheresis was performed in four patients for ABO-incompatible KT, one for antibody-mediated rejection after KT, and the last one for positive T cell crossmatch. Altogether, 46 sessions of plasmapheresis were performed. ABO isoagglutinin titers successfully declined to or below the target level in all patients, and all patients successfully received KT with no significant antibody titer rebound. Acute antibody-mediated rejection and positive T cell crossmatch were well treated with filtration plasmapheresis, and no patient required fresh frozen plasma infusion for coagulopathy. There were one episode of hypotension and three of hypocalcemia. No patients experienced bleeding, infection, or allergic reaction. CONCLUSION: Filtration plasmapheresis was effective and safe. Although our result is from a single center, our protocol appears to be promising.
Filtration* ; Hemorrhage ; Humans ; Hypersensitivity ; Hypocalcemia ; Hypotension ; Immunoglobulin G ; Kidney Transplantation* ; Kidney* ; Korea ; Plasma ; Plasmapheresis* ; Renal Dialysis ; Renal Replacement Therapy* ; Retrospective Studies

BACKGROUND: In peritoneal dialysis, technique failure is an important metric to be considered. This study was performed in order to identify the relationship between trajectories of serum albumin levels and peritoneal dialysis technique failure on end-stage renal disease patients according to diabetic status. Furthermore, this study was performed to reveal predictors of serum albumin and technique failure simultaneously. METHODS: This retrospective cohort study included 300 (189 non-diabetic and 111 diabetic) end-stage renal disease patients on continuous ambulatory peritoneal dialysis treated in Al-Zahra Hospital, Isfahan, Iran, from May 2005 to March 2015. Bayesian joint modeling was carried out in order to determine the relationship between trajectories of serum albumin levels and peritoneal dialysis technique failure in the patients according to diabetic status. Death from all causes was considered as a competing risk. RESULTS: Using joint modeling approach, a relationship between trajectories of serum albumin with hazard of transfer to hemodialysis was estimated as −0.720 (95% confidence interval [CI], −0.971 to −0.472) for diabetic and −0.784 (95% CI, −0.963 to −0.587) for non-diabetic patients. From our findings it was showed that predictors of low serum albumin over time were time on peritoneal dialysis for diabetic patients and increase in age and time on peritoneal dialysis, history of previous hemodialysis, and lower body mass index in non-diabetic patients. CONCLUSION: The results of current study showed that controlling serum albumin over time in non-diabetic and diabetic patients undergoing continuous ambulatory peritoneal dialysis treatment can decrease risk of adverse outcomes during the peritoneal dialysis period.
Body Mass Index ; Cohort Studies ; Humans ; Iran ; Joints* ; Kidney Failure, Chronic ; Peritoneal Dialysis* ; Peritoneal Dialysis, Continuous Ambulatory ; Renal Dialysis ; Retrospective Studies ; Serum Albumin*

BACKGROUND: Salvage of a thrombosed arteriovenous fistula (AVF) by secondary fistula conversion may be more effective than a conventional endovascular procedure for forearm fistula thrombosis. Surgical access procedures are an undeveloped area in interventional nephrology compared to endovascular procedures. Herein, the author report the results of surgical salvage of thrombosed AVFs by interventional nephrologists. METHODS: The author retrospectively analyzed 52 surgical salvage procedures for AVF thrombosis (radiocephalic fistula = 44 cases, brachiocephalic fistula = 8 cases) that were performed by interventional nephrologist between March 2007 and January 2016. RESULTS: Secondary fistula formation using the proximal vein was performed for 46 cases (88.5%); outflow rerouting was performed for two cephalic-arch stenosis cases (3.9%), simple thrombectomy was performed for two cases (3.9%), and a graft interposition was performed for two cases (3.9%). Technical success after the surgical procedures was achieved in 51 cases (98.1%), and 39 AVFs (75.0%) were prepared for immediate puncturing without catheter insertion. The primary and secondary patency rates for AVF at 6, 12, 18, and 24 months were 88.5%, 83.2%, 83.2%, and 83.2% and 96.0%, 96.0%, 93.2%, and 93.2%, respectively. The re-intervention rate was 0.27 ± 0.92/patient/year. CONCLUSION: Based on these results, the author conclude that surgical salvage of a thrombosed AVF, when performed under local anesthesia by a skilled interventional nephrologist, offers favorable short- and long-term success and should be the preferred treatment.
Anesthesia, Local ; Arteriovenous Fistula* ; Catheters ; Constriction, Pathologic ; Endovascular Procedures ; Fistula ; Forearm ; Nephrology ; Retrospective Studies ; Thrombectomy ; Thrombosis ; Transplants ; Veins

BACKGROUND: Polymorphic premature ventricular complexes (PVCs) are very common, appearing most frequently in patients with hypertension, obesity, sleep apnea, and structural heart disease. Sympathetic hyperactivity plays a critical role in the development, maintenance, and aggravation of ventricular arrhythmias. Endurance exercise training clearly lowers sympathetic activity in sympatho-excitatory disease states and may be tolerated by patients with chronic kidney disease (CKD). METHODS: We assessed 40 CKD patients with hypertension with polymorphic PVCs. Patients underwent a complete medical history and physical examination. We evaluated the effectiveness of β blocker only or β blocker + exercise during 12 months of follow-up regarding the changes of the numbers of PVCs and mean heart rate (HR) by 24-hour-Holter. RESULTS: We observed in the β blocker group a significant decrease in the number of polymorphic PVCs from baseline 36,515 ± 3,518 to 3, 6, 9 and 12 months of follow-up, 28,314 ± 2,938, 23,709 ± 1,846, 22,564 ± 1,673, and 22,725 ± 1,415, respectively (P < 0.001). In the β blocker + exercise group a significant decrease in the number of polymorphic PVCs also occurred from baseline 36,091 ± 3,327 to 3, 6, 9 and 12 months of follow-up, 29,252 ± 3,211, 20,948 ± 2,386, 14,238 ± 3,338, and 6,225 ± 2,319, respectively (P < 0.001). Comparisons between the two groups at the same time point showed differences from the sixth month onwards: the 6th (Δ = −2,761, P = 0.045), 9th (Δ = −8,325, P < 0.001) and 12th (Δ = −16,500, P < 0.001) months. There was an improvement during the 12 months of follow-up vs. baseline, after the β blocker or β blocker + exercise in mean 24-hour HR Holter monitoring, creatinine values, eGFR, and ACR. CONCLUSION: Polymorphic PVCs may be modifiable by physical activity in CKD patients with hypertension without structural heart disease.
Arrhythmias, Cardiac ; Creatinine ; Electrocardiography, Ambulatory ; Follow-Up Studies ; Heart Diseases ; Heart Rate ; Humans ; Hypertension ; Motor Activity* ; Obesity ; Physical Examination ; Renal Insufficiency, Chronic* ; Sleep Apnea Syndromes ; Ventricular Premature Complexes*

BACKGROUND: Mizoribine (MZR) is an immunosuppressive drug used in Japan for treating patients with lupus nephritis and nephrotic syndrome and has been also reportedly effective in patients with immunoglobulin A (IgA) nephropathy. However, to date, few randomized control studies of MZR are performed in patients with IgA nephropathy. Therefore, this prospective, open-label, randomized, controlled trial aimed to investigate the efficacy and safety of adding MZR to standard treatment in these patients, and was conducted between April 1, 2009, and March 31, 2016, as a multicenter study. METHODS: Patients were randomly assigned (1:1) to receiving standard treatment plus MZR (MZR group) or standard treatment (control group). MZR was administered orally at a dose of 150 mg once daily for 12 months. RESULTS: Primary outcomes were the percentage reduction in urinary protein excretion from baseline and the rate of patients with hematuria disappearance 36 months after study initiation. Secondary outcomes were the rate of patients with proteinuria disappearance, clinical remission rate, absolute changes in estimated glomerular filtration rate from baseline, and the change in daily dose of prednisolone. Forty-two patients were randomly assigned to MZR (n = 21) and control groups (n = 21). Nine patients in MZR group and 15 patients in the control group completed the study. No significant differences were observed between the two groups with respect to primary and secondary outcomes. CONCLUSION: The addition of MZR to standard treatment has no beneficial effect on reducing urinary protein excretion and hematuria when treating patients with IgA nephropathy.
Glomerular Filtration Rate ; Glomerulonephritis, IGA* ; Hematuria ; Humans ; Immunoglobulin A* ; Immunoglobulins* ; Japan ; Lupus Nephritis ; Nephrotic Syndrome ; Prednisolone ; Prospective Studies ; Proteinuria