Understanding the Korean Dialysis Cohort for Mineral, Vascular Calcification, and Fracture (ORCHESTRA) Study: Design, Method, and Baseline Characteristics.

INTRODUCTION: End-stage renal disease (ESRD) is a growing disease worldwide, including Korea. This is an important condition that affects patient outcome. To provide optimal management for mineral disturbance, vascular calcification, and bone disease in ESRD patients, the Korean dialysis cohort for mineral, vascular calcification, and fracture (ORCHESTRA) study was conducted by enrolling Korean dialysis patients. METHODS: Sixteen university-affiliated hospitals and one Veterans' Health Service Medical Center participated in this study. This prospective cohort study enrolled approximately 900 consecutive patients on dialysis between May 2019 and January 2021. Enrolled subjects were evaluated at baseline for demographic information, laboratory tests, radiologic imaging, and bone mineral densitometry (BMD) scans. After enrollment, regular assessments of the patients were performed, and their biospecimens were collected according to the study protocol. The primary outcomes were the occurrence of major adverse cardiovascular events, invasive treatment for peripheral artery disease, and osteoporotic fractures. The secondary outcomes were hospitalization for cerebrovascular disease or progression of abdominal aortic calcification. Participants will be assessed for up to 3 years to determine whether primary or secondary outcomes occur. RESULTS: Between May 2019 and January 2021, all participating centers recruited 900 consecutive dialysis patients, including 786 undergoing hemodialysis (HD) and 114 undergoing peritoneal dialysis (PD). The mean age of the subjects was 60.4 ± 12.3 years. Males accounted for 57.7% of the total population. The mean dialysis vintage was 6.1 ± 6.0 years. The HD group was significantly older, had a longer dialysis vintage, and more comorbidities. Overall, the severity of vascular calcification was higher and the level of BMD was lower in the HD group than in the PD group. CONCLUSION: This nationwide, multicenter, prospective cohort study focused on chronic kidney disease-mineral and bone disorder and aimed to provide clinical evidence to establish optimal treatment guidelines for Asian dialysis patients.

Effect of low-density lipoprotein level and mortality in older incident statin-naïve hemodialysis patients.

BACKGROUND: This study aimed to analyze low-density lipoprotein cholesterol (LDL-C) levels and their relationship with mortality in order to identify the appropriate lipid profile for older Korean hemodialysis patients. METHODS: We enrolled a total of 2,732 incident hemodialysis patients aged > 70 years from a retrospective cohort of the Korean Society of Geriatric Nephrology from 2010 Jan to 2017 Dec, which included 17 academic hospitals in South Korea. Of these patients, 1,709 were statin-naïve, and 1,014 were analyzed after excluding those with missing LDL-C level data. We used multivariate Cox regression analysis to select risk factors from 20 clinical variables among the LDL-C groups. RESULTS: The mean age of the entire patient population was 78 years, with no significant differences in age between quartiles Q1 to Q4. However, the proportion of males decreased as the quartiles progressed towards Q4 (p < 0.001). The multivariate Cox regression analysis, which included all participants, showed that low LDL-C levels were associated with all-cause mortality. In the final model, compared to Q1, the hazard ratios (95% confidence interval) were 0.77 (0.620-0.972; p = 0.027), 0.85 (0.676-1.069; p = 0.166), and 0.65 (0.519-0.824; p < 0.001) for Q2, Q3, and Q4, respectively, after adjusting for covariates, such as conventional and age-specific risk factors. The final model demonstrated that all-cause mortality increased as LDL-C levels decreased, as confirmed by a restrictive cubic spline plot. CONCLUSIONS: In older hemodialysis patients who had not previously received dyslipidemia treatment, elevated LDL-C levels were not associated with increased all-cause mortality. Intriguingly, lower LDL-C levels appear to be associated with an unfavorable effect on all-cause mortality among high-risk hemodialysis patients.

Nutritional and Dietary Management of Chronic Kidney Disease Under Conservative and Preservative Kidney Care Without Dialysis.

While dialysis has been the prevailing treatment paradigm for patients with advanced chronic kidney disease (CKD), emphasis on conservative and preservative management in which dietary interventions are a major cornerstone have emerged. Based on high-quality evidence, international guidelines support the utilization of low-protein diets as an intervention to reduce CKD progression and mortality risk, although the precise thresholds (if any) for dietary protein intake vary across recommendations. There is also increasing evidence demonstrating that plant-dominant low-protein diets reduce the risk of developing incident CKD, CKD progression, and its related complications including cardiometabolic disease, metabolic acidosis, mineral and bone disorders, and uremic toxin generation. In this review, we discuss the premise for conservative and preservative dietary interventions, specific dietary approaches used in conservative and preservative care, potential benefits of a plant-dominant low-protein diet, and practical implementation of these nutritional strategies without dialysis.

Molecular Mechanisms Associated with Aging Kidneys and Future Perspectives.

The rapid growth of the elderly population is making the need for extensive and advanced information about age-related organ dysfunction a crucial research area. The kidney is one of the organs most affected by aging. Aged kidneys undergo functional decline, characterized by a reduction in kidney size, decreased glomerular filtration rate, alterations in renal blood flow, and increased inflammation and fibrosis. This review offers a foundation for understanding the functional and molecular mechanisms of aging kidneys and for selecting identifying appropriate targets for future treatments of age-related kidney issues.

Revisiting glomerular hyperfiltration and examining the concept of high dietary protein-related nephropathy in athletes and bodybuilders.

PURPOSE OF REVIEW: High-protein diets (HPDs) are popular but their consequences for kidney health, especially among athletes and bodybuilders who typically maintain a high protein intake for a long time, have not been investigated. This review focused on recent studies of the association of HPD with long-term kidney health and the concept of high dietary protein-related nephropathy. RECENT FINDINGS: Several long-term observational studies including large populations have reinforced the notion that HPDs are associated with a rapid decline of kidney function. An increase in renal blood flow and glomerular hyperfiltration caused by vasodilation, and increased levels of endocrine and paracrine factors (glucagon, IGF-1, prostanoids, and nitric oxide), facilitates the excretion of protein-derived nitrogenous waste. Inhibition of tubule-glomerular feedback and increased proximal tubular Na+ reabsorption after a HPD augment glomerular hyperfiltration and may trigger synthesis of proinflammatory cytokines and receptor for advanced glycation end-products (RAGE). Focal segmental glomerulosclerosis reported in association with anabolic steroid may indeed be a HPD nephropathy given that HPD results in progressive glomerulosclerosis, especially in remnant glomeruli or in diabetic kidney disease but can happen in any high-risk situation, such as solitary kidney and polycystic kidneys. SUMMARY: HPD among athletes and bodybuilders in an extreme way across a long-term period may pose a risk to renal health including high incidence of HPD nephropathy.

Association between physical activity and risk of renal function decline and mortality in community-dwelling older adults: a nationwide population-based cohort study.

BACKGROUND: Physical activity (PA) is an important risk factor associated with health outcomes. However, the relationship between PA and kidney function decline in older adults remains unclear. We examined the influence of PA on kidney function decline and mortality in community-dwelling older adults. METHODS: Adults aged ≥ 65 years with an estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73 m2 who had available health checkup data from 2009 to 2010 were included. The cohort was followed annually through December 2015 for anthropometric, sociodemographic, and medical information including outcomes and biennially for laboratory information from the health checkup. We divided these patients into three groups according to self-reported PA (Inactive group: no leisure-time PA, Active group: vigorous activity for at least 80 min/week or a sum of moderate-intensity activity and walking for at least 300 min/week, Low-active group: level of PA between the definitions of the other two groups). Associations between the intensity of PA and death, cardiovascular death, and ≥ 50% eGFR decline were investigated. RESULTS: Among 102,353 subjects, 32,984 (32.23%), 54,267 (53.02%), and 15,102 (14.75%) were classified into the inactive, low-active, and active groups, respectively. The active group was younger, contained a higher proportion of men, and had higher frequencies of hypertension, diabetes mellitus, drinking, and smoking than the other groups. The active group had significantly lower incidence rates of mortality, cardiovascular mortality, and kidney function decline than the other groups (all p < 0.001). The active group also showed lower all-cause (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.70-0.82) and cardiovascular mortality (HR, 0.64; 95% CI, 0.53-0.78) and protection against ≥ 50% eGFR decline (HR, 0.81; 95% CI, 0.68-0.97) compared with the inactive group in the fully adjusted Cox proportional hazards regression model. CONCLUSIONS: High PA was an independent modifiable lifestyle factor for reducing mortality and protecting against declines in kidney function in older adults.

Waist-hip ratio measured by bioelectrical impedance analysis as a valuable predictor of chronic kidney disease development.

Obesity is a major health problem worldwide and is associated with chronic kidney disease (CKD). Body mass index (BMI) is a common method of diagnosing obesity, but there are concerns about its accuracy and ability to measure body composition. This study evaluated the risk of CKD development in a middle-aged population in association with various body composition metrics. From a prospective cohort of 10,030 middle-aged adults, we enrolled 6727 for whom baseline and follow-up data were available. We collected data pertaining to participants' BMI, manually measured waist-hip ratio (WHR), and various measurements of bioelectrical impedance analysis (BIA), including total body fat content, muscle content, and calculated WHR, and classified the participants into quintiles accordingly. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 in follow-up laboratory tests. While an increase in BMI, WHR, and total body fat were associated with an elevated risk of CKD, an increase in total body muscle decreased the risk. Among the body composition metrics, WHR measured by BIA had the highest predictive value for CKD (C-statistics: 0.615). In addition, participants who were "healthy overweight, (defined as low WHR but high BMI), exhibited a 62% lower risk of developing CKD compared to those with "normal-weight obesity," (defined as high WHR despite a normal BMI). In conclusion, we suggest that central obesity measured by BIA is a more accurate indicator than BMI for predicting the development of CKD.

The Roles and Associated Mechanisms of Adipokines in Development of Metabolic Syndrome.

Metabolic syndrome is a cluster of metabolic indicators that increase the risk of diabetes and cardiovascular diseases. Visceral obesity and factors derived from altered adipose tissue, adipokines, play critical roles in the development of metabolic syndrome. Although the adipokines leptin and adiponectin improve insulin sensitivity, others contribute to the development of glucose intolerance, including visfatin, fetuin-A, resistin, and plasminogen activator inhibitor-1 (PAI-1). Leptin and adiponectin increase fatty acid oxidation, prevent foam cell formation, and improve lipid metabolism, while visfatin, fetuin-A, PAI-1, and resistin have pro-atherogenic properties. In this review, we briefly summarize the role of various adipokines in the development of metabolic syndrome, focusing on glucose homeostasis and lipid metabolism.

Impact of water consumption on renal function in the general population: a cross-sectional analysis of KNHANES data (2008-2017).

BACKGROUND: The renoprotective effect of water intake remains unclear. We aimed to investigate the relationship between water intake and renal impairment in the Korean general population, focusing on individual differences in body fluid distribution and risk of chronic dehydration. METHODS: We conducted a cross-sectional analysis of the 2008-2017 Korea National Health and Nutrition Examination Survey (KNHANES). Adult participants who had body weight and serum creatinine data and had answered 24-h recall nutritional survey were included. Four water intake groups were defined by daily total water intake per body weight: lowest (< 20 mL/kg/day), low-moderate (20-29.9 mL/kg/day), high-moderate (30-49.9 mL/kg/day), and highest (≥ 50 mL/kg/day). We assessed the risk of renal impairment (estimated glomerular filtration rate ≤ 60 mL/min/1.73 m2) according to water intake. RESULTS: In total of 50,113 participants, 3.9% had renal impairment. The risk of renal impairment gradually decreased as water intake increased. After adjustment of sodium intake, the trend of renoprotective effect was remained in low-moderate and high-moderate water intake group compared to low intake group, whereas no significant impact was observed with the highest water intake due to concurrent intake of high sodium. In subgroup analysis, the renoprotective effect of water intake was significant in the participants with elderly, male and daily sodium intake over 2 g/day. CONCLUSIONS: High daily water intake is renoprotective. Our data may provide an important basis for determining the amount of water intake needed to prevent renal impairment, considering variations in body weight, body composition and risk of chronic dehydration.

The Effects of High-Protein Diets on Kidney Health and Longevity.

Although high-protein diets continue to be popular for weight loss and type 2 diabetes, evidence suggests that worsening renal function may occur in individuals with-and perhaps without-impaired kidney function. High dietary protein intake can cause intraglomerular hypertension, which may result in kidney hyperfiltration, glomerular injury, and proteinuria. It is possible that long-term high protein intake may lead to de novo CKD. The quality of dietary protein may also play a role in kidney health. Compared with protein from plant sources, animal protein has been associated with an increased risk of ESKD in several observational studies, including the Singapore Chinese Health Study. Potential mediators of kidney damage from animal protein include dietary acid load, phosphate content, gut microbiome dysbiosis, and resultant inflammation. In light of such findings, adopting current dietary approaches that include a high proportion of protein for weight reduction or glycemic control should be considered with care in those at high risk for kidney disease. Given the possibility of residual confounding within some observational studies and the conflicting evidence from previous trials, long-term studies including those with large sample sizes are warranted to better ascertain the effects of high protein intake on kidney health.

Comparing Patient Survival of Home Hemodialysis and Peritoneal Dialysis Patients.

BACKGROUND: It is not clear whether peritoneal dialysis (PD) and home hemodialysis (HHD) have similar outcomes, and little is known about how mortality associated with HHD versus PD differs according to the duration of dialysis. METHODS: We examined a national cohort of incident end-stage renal disease patients that was comprised of 1,993 and 16,514 patients transitioning to HHD and PD, respectively, from 2007 to 2011. The HHD patients were matched with PD patients using propensity score (PS). Demographics, comorbidities, duration of dialysis, and body mass index were adjusted for in logistic regression models using PS matching. We matched 1,915 HHD patients with 1,915 PD patients based on the PS. The patients were categorized by their vintage (duration of dialysis) at the time of the transition to HHD or PD (<3, 3 to <12, and ≥12 months). RESULTS: In the matched cohort, 237 and 359 deaths occurred in the HHD and PD patients, respectively (cumulative incidence 9.6 vs. 12.9/100 patient-years, p < 0.001). PD patients who transitioned within 12 months of starting dialysis had similar mortality risks, while PD patients who transitioned >12 months after starting dialysis had an 83% higher risk for mortality (hazard ratio 1.83; 95% CI 1.33-2.52). CONCLUSIONS: Whereas there was no meaningful survival difference in the first 12 months between HHD and PD, patients who transitioned to PD after 12 months of dialysis had worse survival than their HHD counterparts. Additional studies are warranted to investigate clinical implications of these differences.

Vascular access placement and mortality in elderly incident hemodialysis patients.

BACKGROUND: Arteriovenous fistulas (AVFs) are the preferred vascular access type in most hemodialysis patients. However, the optimal vascular access type in octogenarians and older (≥80 years) hemodialysis patients remains widely debated given their limited life expectancy and lower AVF maturation rates. METHODS: Among incident hemodialysis patients receiving care in a large national dialysis organization during 2007-2011, we examined patterns of vascular access type conversion in 1 year following dialysis initiation in patients <80 versus ≥80 years of age. Among a subcohort of patients ≥80 years of age, we examined the association between vascular access type conversion and mortality using multivariable survival models. RESULTS: In the overall cohort of 100 804 patients, the prevalence of AVF/arteriovenous graft (AVG) as the primary vascular access type increased during the first year of hemodialysis, but plateaued thereafter. Among 8356 patients ≥80 years of age and treated for >1 year, those with initial AVF/AVG use and placement of AVF from a central venous catheter (CVC) had lower mortality compared with patients with persistent CVC use. When the reference group was changed to patients who had AVF placement from a CVC in the first year of dialysis, those with initial AVF use had similar mortality. A longer duration of CVC use was associated with incrementally worse survival. CONCLUSIONS: Among incident hemodialysis patients ≥80 years of age, placement of an AVF from a CVC within the first year of dialysis had similar mortality compared with initial AVF use. Our data suggest that initial CVC use with later placement of an AVF may be an acceptable option among elderly hemodialysis patients.

Clinical Predictors Implicated in the Incidence of Acute Pyelonephritis during the Antepartum Period: A Population-Based Cohort Study.

INTRODUCTION: Acute pyelonephritis (APN) is a common infection during pregnancy that increases the risk of unfavorable maternal and fetal outcomes. However, it has not been clearly elucidated which demographic and clinical characteristics are associated with the incidence of APN during pregnancy. OBJECTIVE: This population-based cohort study aimed to determine the risk factors for APN during pregnancy. METHODS: Using the database of the Health Insurance Review and Assessment Service of South Korea, we enrolled Korean women who delivered infants between 2010 and 2014 in Korea and had complete health examination records within 1 year of pregnancy. We performed multivariate logistic regression analysis to evaluate the risk factors for APN during pregnancy. RESULTS: Of 370,248 women, 2,526 (0.7% of the total participants) were treated for APN while in hospitalization during pregnancy. Younger age, history of previous APN within 1 year of pregnancy, and abnormal results of health examination before pregnancy, such as high fasting glucose level (>100 mg/dL) and proteinuria, were associated with an increased risk of APN during pregnancy. CONCLUSION: Certain maternal demographic and clinical characteristics were associated with the incidence of APN during pregnancy, and these should be monitored closely during antenatal care.

High dose haemodialysis and haemodiafiltration parameters and the relationship with advanced vascular calcification.

BACKGROUND: Vascular calcification (VC) is a risk factor for cardiovascular disease in end-stage renal disease (ESRD) patients undergoing maintenance haemodialysis (MHD). However, evidence is still insufficient about the association between dialysis parameters and VC. Thus, this study was to evaluate association of dialysis parameters with VC. METHODS: We enrolled 297 ESRD patients undergoing MHD at six distinct centers in Korea. Study participants were categorized into 3 groups by the scoring system of abdominal aortic calcification based on lateral lumbar radiography (no VC group: 0, mild VC group: 1-7 and advanced VC group: 8-24). We compared the features of dialysis parameters according to the severity of VC. Multivariate logistic regression analysis was used to calculate adjusted odd ratios (ORs) and 95% confidence interval (CI) for mild and advanced VC in each haemodialysis parameter (adjusted OR [95% CI]). RESULTS: Pooled Kt/V (spKt/V), equilibrated Kt/V (eKt/V), standard Kt/V (stdKt/V) and the proportion of haemodiafiltration were increased along with the severity of VC. Multivariate regression analysis indicated that advanced VC was positively associated with spKt/V (5.27 [1.51-18.41]), eKt/V (6.16 [1.45-26.10]), stdKt/V (10.67 [1.74-65.52]) and haemodiafiltration (3.27 [1.74 to 6.16]). CONCLUSION: High dose dialysis and haemodiafiltration were significantly associated with advanced VC.

Gait speed and handgrip strength as predictors of all-cause mortality and cardiovascular events in hemodialysis patients.

BACKGROUND: Low physical performance in patients undergoing maintenance hemodialysis is associated with a high mortality rate. We investigated the clinical relevance of gait speed and handgrip strength, the two most commonly used methods of assessing physical performance. METHODS: We obtained data regarding gait speed and handgrip strength from 277 hemodialysis patients and evaluated their relationships with baseline parameters, mental health, plasma inflammatory markers, and major adverse clinical outcomes. Low physical performance was defined by the recommendations suggested by the Asian Working Group on Sarcopenia. RESULTS: The prevalence of low gait speed and handgrip strength was 28.2 and 44.8%, respectively. Old age, low serum albumin levels, high comorbidity index score, and impaired cognitive functions were associated with low physical performance. Patients with isolated low gait speed exhibited a general trend for worse quality of life than those with isolated low handgrip strength. Gait speed and handgrip strength showed very weak correlations with different determining factors (older age, the presence of diabetes, and lower serum albumin level for low gait speed, and lower body mass index and the presence of previous cardiovascular events for low handgrip strength). Patients with low gait speed and handgrip strength had elevated levels of plasma endocan and matrix metalloproteinase-7 and the highest risks for all-cause mortality and cardiovascular events among the groups (adjusted hazard ratio of 2.72, p = 0.024). Elderly patients with low gait speed and handgrip strength were at the highest risk for poor clinical outcomes. CONCLUSION: Gait speed and handgrip strength reflected distinctive aspects of patient characteristics and the use of both factors improved the prediction of adverse clinical outcomes in hemodialysis patients. Gait speed seems to be a better indicator of poor patient outcomes than is handgrip strength.

The Role of Sirtuins in Kidney Diseases.

Sirtuins (SIRTs) are class III histone deacetylases (HDACs) that play important roles in aging and a wide range of cellular functions. Sirtuins are crucial to numerous biological processes, including proliferation, DNA repair, mitochondrial energy homeostasis, and antioxidant activity. Mammals have seven different sirtuins, SIRT1-7, and the diverse biological functions of each sirtuin are due to differences in subcellular localization, expression profiles, and cellular substrates. In this review, we summarize research advances into the role of sirtuins in the pathogenesis of various kidney diseases including acute kidney injury, diabetic kidney disease, renal fibrosis, and kidney aging along with the possible underlying molecular mechanisms. The available evidence indicates that sirtuins have great potential as novel therapeutic targets for the prevention and treatment of kidney diseases.

No Survival Benefit in Octogenarians and Nonagenarians with Extended Hemodialysis Treatment Time.

BACKGROUND: The population of elderly end-stage renal disease patients initiating dialysis is rapidly growing. Although longer treatment is supposed to benefit for hemodialysis (HD) patients through more solute clearance and slower fluid removal, it is not yet clear how treatment session length affects mortality risk in octogenarians and nonagenarians. METHODS: In a cohort of 112,026 incident HD patients between 2007 and 2011, we examined the association of treatment session length with all-cause mortality, adjusting for demographics and comorbid conditions. We also used restricted spline functions for age to evaluate continuous changes in the association of short (< 210 min) and extended (≥240 min) HD treatment (vs. 210 to < 240 min) with all-cause mortality over continuous age. RESULTS: During the first 91 days of dialysis, patients aged ≥80 years tended to have the lowest treatment session length (median [interquartile range] 211 [193-230] min, r > 0.5). Longer treatment was associated with better survival in patients < 65 and 65 to < 80 years but not in octogenarians/nonagenarians. The association of extended treatment (≥240 min) with better survival was attenuated across age and not significant among patients aged ≥80 years with a hazard ratio of 1.10 (95% CI 0.99-1.20). Shorter treatment sessions (< 210 min) was associated with higher mortality across all age groups. CONCLUSION: Extended HD was not associated with lower mortality among octogenarians and nonagenarians, while it was associated with better survival among younger patients. Further studies are needed to determine the optimal treatment session length in elderly incident HD patients.

Dietary protein intake and chronic kidney disease.

PURPOSE OF REVIEW: High-protein intake may lead to increased intraglomerular pressure and glomerular hyperfiltration. This can cause damage to glomerular structure leading to or aggravating chronic kidney disease (CKD). Hence, a low-protein diet (LPD) of 0.6-0.8 g/kg/day is often recommended for the management of CKD. We reviewed the effect of protein intake on incidence and progression of CKD and the role of LPD in the CKD management. RECENT FINDINGS: Actual dietary protein consumption in CKD patients remains substantially higher than the recommendations for LPD. Notwithstanding the inconclusive results of the 'Modification of Diet in Renal Disease' (MDRD) study, the largest randomized controlled trial to examine protein restriction in CKD, several prior and subsequent studies and meta-analyses appear to support the role of LPD on retarding progression of CKD and delaying initiation of maintenance dialysis therapy. LPD can also be used to control metabolic derangements in CKD. Supplemented LPD with essential amino acids or their ketoanalogs may be used for incremental transition to dialysis especially on nondialysis days. The LPD management in lieu of dialysis therapy can reduce costs, enhance psychological adaptation, and preserve residual renal function upon transition to dialysis. Adherence and adequate protein and energy intake should be ensured to avoid protein-energy wasting. SUMMARY: A balanced and individualized dietary approach based on LPD should be elaborated with periodic dietitian counseling and surveillance to optimize management of CKD, to assure adequate protein and energy intake, and to avoid or correct protein-energy wasting.

Resveratrol Ameliorates Contrast Induced Nephropathy Through the Activation of SIRT1-PGC-1α-Foxo1 Signaling in Mice.

BACKGROUND/AIMS: SIRT1 activation promotes the resistance of renal tubular cells to oxidative stress, and resveratrol is known as a SIRT1 activator. METHODS: Resveratrol was injected intraperitoneally with iohexol for 24 hours. NRK-52E cells were pretreated with resveratrol for 24 hours and then exposed to iohexol for 3 hours. Renal function was measured by serum creatinine and cell survival was assessed by MTT assay. We investigated whether resveratrol attenuates oxidative stress and apoptosis in contrast-induced nephropathy (CIN). RESULTS: Serum creatinine and tubular injury increased significantly after iohexol treatment, and resveratrol co-treatment attenuated the renal injury. Cell survival decreased after iohexol exposure and resveratrol reduced cell death induced by iohexol. Resveratrol was accompanied with the activation of SIRT1 and PGC-1α and dephosphorylation of FoxO1 in mice with CIN. SIRT1 and PGC-1α expression were decreased by iohexol, and increased significantly in resveratrol-pretreated cells. These processes resulted in reduction of oxidative stress and apoptosis both in vivo and in vitro experiments. Resveratrol decreased inflammatory cell infiltration induced by iohexol in mice with CIN. SIRT1 inhibition using siRNA in tubular cells accentuated the decrease of cell viability by iohexol. CONCLUSION: Resveratrol attenuated CIN by modulating renal oxidative stress and apoptosis through activation of SIRT1-PGC-1α-FoxO1 signaling.

Raoultella planticola peritonitis in a patient on continuous ambulatory peritoneal dialysis.

A 65-year-old man on continuous ambulatory peritoneal dialysis was admitted with peritonitis. Empirical antibiotic therapy was initiated, and Raoultella planticola was identified in the peritoneal fluid culture. We treated the patient with intraperitoneally administered ciprofloxacin and ceftazidime according to the antibiotic susceptibility. His condition improved, and he was well treated with a 2-week antibiotic course.