Reduced Residual Renal Function is Associated with Endothelial Dysfunction in Patients Receiving Peritoneal Dialysis

♦ Background: Endothelial dysfunction, which contributes to atherosclerosis and arteriosclerosis, commonly accompanies end-stage renal disease (ESRD). However, little is known about the role of residual renal function (RRF) in endothelial protection in ESRD patients. This study aimed to investigate the relationship between endothelial function and RRF in patients undergoing peritoneal dialysis (PD).♦ Methods: This was a cross-sectional study involving 72 prevalent PD patients. Demographic and clinical data were recorded and residual glomerular filtration rate (GFR), Kt/V urea, and serum concentrations of inflammatory markers were measured. Endothelial function was assessed by brachial artery endothelium-dependent vasodilation [flow-mediated dilation (FMD)] to reactive hyperemia following 5 minutes of forearm ischemia.♦ Results: In patients with FMD% above the median value (FMD > 2.41%), residual GFR was significantly higher compared to that in patients with FMD% below the median [1.50 (0 – 9.64) vs 0.48 (0 – 3.89) mL/min/1.73 m², P = 0.026]. Correlation analyses revealed that residual GFR (ρ = 0.381, P = 0.001) and total Kt/V urea (γ = 0.408, P < 0.001) were positively correlated with FMD%, whereas PD duration (γ = –0.351, P = 0.003), high-sensitivity C-reactive protein (ρ = –0.345, P = 0.003), pulse pressure (γ = –0.341, P = 0.003), and age (γ = –0.403, P < 0.001) were inversely correlated with FMD%. In contrast, there was no correlation between peritoneal Kt/V urea and FMD%. In multivariate linear regression analysis adjusted for these factors, residual GFR was found to be an independent determinant of FMD% (β = 0.317, P = 0.017).♦ Conclusion: This study shows that RRF is independently associated with endothelial dysfunction in ESRD patients on PD, suggesting that RRF may contribute to endothelial protection in these patients.     

Impact of Hernias on Peritoneal Dialysis Technique Survival and Residual Renal Function

♦ Objective: We evaluated the effect of hernias and their surgical or conservative management on peritoneal dialysis (PD) technique survival and residual renal function.♦ Methods: This 10-year single-center retrospective case-control study (January 2001 - January 2011) compared patient survival, PD technique survival, and residual renal function in patients with a history of abdominal hernias and in a control cohort matched for age and PD vintage.♦ Results: Of 73 hernias identified in 63 patients (mean age: 55 years; 63% men), umbilical hernias were the most frequent (40%), followed by inguinal (33%), incisional, and epigastric hernias. Some hernias were surgically repaired before (n = 10) or at the time of PD catheter insertion (n = 11), but most (71%) were diagnosed and managed after initiation of PD.Overall, 49 of 73 (67%) hernias were treated surgically. In 53% of subjects, early postoperative dialysis was not needed; only 7 patients required temporary hemodialysis. The occurrence of a hernia and its treatment did not significantly affect residual renal function. After a hernia diagnosis or repair, 86% of patients were able to continue with PD.♦ Conclusions: The incidence of abdominal hernia and hernia management in patients on PD do not significantly influence residual renal function or PD technique survival. Timely management of hernias is advisable and does not preclude continuation with PD as a dialysis modality.     

Urinary Biomarkers for Sensitive and Specific Detection of Acute Kidney Injury in Humans

Acute kidney injury (AKI) is associated with high morbidity and mortality. The lack of sensitive and specific injury biomarkers has greatly impeded the development of therapeutic strategies to improve outcomes of AKI.The unique objective of this study was to evaluate the diagnostic performance of nine urinary biomarkers of AKI—kidney injury molecule‐1 (KIM‐1), neutrophil gelatinase associated lipocalin (NGAL), interleukin‐18 (IL‐18), hepatocyte growth factor (HGF), cystatin C (Cys), N‐acetyl‐β‐D‐glucosaminidase (NAG), vascular endothelial growth factor (VEGF), chemokine interferon‐inducible protein 10 (IP‐10; CXCL10), and total protein—in a cross‐sectional comparison of 204 patients with or without AKI.Median urinary concentrations of each biomarker were significantly higher in patients with AKI than in those without AKI (p < 0.001). The area under the receiver operating characteristics curve (AUC‐ROC) for the combination of biomarkers using a logic regression model [risk score of 2.93*(NGAL > 5.72 and HGF > 0.17) + 2.93*(PROTEIN > 0.22) −2*(KIM < 0.58)] was greater (0.94) than individual biomarker AUC‐ROCs. Age‐adjusted levels of urinary KIM‐1, NAG, HGF, VEGF, and total protein were significantly higher in patients who died or required renal replacement therapy (RRT) when compared to those who survived and did not require RRT.Our results demonstrate the comparative value of multiple biomarkers in the diagnosis and prognosis of AKI.     

Serum Concentrations of p-Cresyl Sulfate and Indoxyl Sulfate,but Not Inflammatory Markers,Increase in Incident Peritoneal Dialysis Patients in Parallel with Loss of Residual Renal Function

♦ Background: High serum concentrations of the protein-bound uremic retention solutes p-cresyl sulfate (PCS) and indoxyl sulfate (IndS) and inflammation are associated with increased cardiovascular morbidity and mortality in chronic kidney disease. Renal clearance contributes to up to 80% of the total clearance of PCS and IndS in peritoneal dialysis (PD) patients. Cross-sectional studies evaluating the impact of residual renal function (RRF) on serum concentrations of PCS, IndS, and circulating inflammatory markers have yielded conflicting results.♦ Methods: To clarify this issue, we carried out a prospective observational cohort study in incident PD patients (n = 35; 19 men; mean age: 55 ± 17 years). Midday blood samples were collected and analyzed for total serum PCS, IndS, C-reactive protein, and high-sensitivity interleukin 6. Peritoneal and renal clearances were calculated from urine and dialysate collections, and RRF was calculated as the mean of renal urea nitrogen and creatinine clearances. Patients were assessed 1, 6, 12, and 24 months after PD start. Differences between time points were analyzed using linear mixed models (LMMs).♦ Results: Residual renal function declined significantly over time (LMM p < 0.0001). Peritoneal clearances of both toxins tended to increase, but did not compensate for the declining renal clearances. Serum concentrations of PCS and IndS increased significantly over time (LMM p = 0.01; p = 0.0009). In contrast, total mass removal of both toxins remained stable. Circulating inflammatory markers did not change over time.♦ Conclusions: Our data indicate that serum concentrations of PCS and IndS, but not inflammatory markers, increase in incident PD patients in parallel with loss of RRF.     

Influence of Renal Function on the Urinary Excretion of Amylase

Urinary excretion of endogenous amylase was studied during osmotic diuresis in normal rats and in rats with different kinds of induced kidney damage. In normal rats the amylase excretion varied almost proportionally with respect to plasma concentration of amylase and to glomerular filtration rate (GFR), estimated as clearance for polyethylene glycol 1000 (PEG 1000). The ratio between amylase clearance and GFR varied only slightly with body weight and was independent of urine flow in normal rats. Both increased glomerular permeability to proteins in aminonucleoside-nephrosis and tubular dysfunction after sodium maleate treatment augmented the ratio of amylase clearance to GFR. A considerable tubular reabsorption of amylase in normal rats is concluded. In unilateral pyelonephritis or unilateral ischemic kidney damage this ratio remained constant, but when the functional kidney mass was reduced by removal of the intact kidney, it increased considerably, possibly owing to decreased fractional reabsorption of fluid in the proximal tubules and increased glomerular filtration of proteins per nephron.     

Implementing an Annual Renal Function Screening Protocol in Primary Care

Early detection of renal damage in diabetic and hypertensive patients in the primary care setting was the focus of a quality improvement project. A protocol requiring renal function screening for 150 patients meeting the inclusion criteria was implemented in a southern, rural primary care clinic. A pre- and postintervention chart review determined if the intervention was significant in increasing the number of renal function screenings preformed. The results indicated that implementing the protocol did indeed increase the number of renal function screenings performed and identified undiagnosed chronic kidney disease.     

Prediction of Tubulointerstitial Injury in Chronic Kidney Disease Using a Non-Invasive Model: Combination of Renal Sonography and Laboratory Biomarkers

The goal of the study described here was to evaluate the degree of tubulointerstitial injury in patients with chronic kidney disease (CKD) using a more accurate model that combines renal sonographic parameters and laboratory biomarkers. A total of 308 patients were enrolled. The study protocol included conventional ultrasound, contrast-enhanced ultrasonography and renal biopsy. CKD patients were divided into normal and mild (≤25%), moderate (26%–50%) and severe (>50%) tubulointerstitial injury groups. We created a model comprising peak intensity, time to peak, urinary retinol-binding protein and β₂-microglobulin that could discriminate severe (>50%) tubulointerstitial injury. The area under the receiver operating characteristic curve of this model was 0.832, which had better accuracy than other individual indexes, and the sensitivity and specificity were 74.2% and 82.8%, respectively. Therefore, this model may be used to evaluate the severity of tubulointerstitial injury and may have the potential to serve as an effective auxiliary method to help nephrologists evaluate patients with CKD.     

Presence of Peripheral Arterial Disease Predicts Loss of Residual Renal Function in Incident CAPD Patients

♦ Background: Accelerated cardiovascular disease (CVD), including peripheral arterial disease (PAD), is very common in patients with end-stage renal disease. Residual renal function (RRF) is a strong predictor of patient survival that is suggested to be linked to the degree of CVD. However, the relationship between PAD and decline in RRF has not previously been measured.♦ Methods: We studied incident continuous ambulatory peritoneal dialysis patients from Peking University Third Hospital. An ankle brachial index of less than 0.9 was used to diagnose PAD. Residual renal function (RRF) was determined as the mean of 24-hour urea and creatinine clearances (glomerular filtration rate). The Cox proportional hazards model was used to identify factors predicting loss of RRF.♦ Results: The study included 86 patients (age: 61 ± 14 years; men: 51%), 23 of whom had PAD at baseline. Mean follow-up was 19 months (median: 18 months; range: 6 – 30 months). In univariate analysis, baseline PAD, peritonitis during follow-up, inflammation (C-reactive protein), serum uric acid, Ca×P, and serum phosphate were all significantly associated with a greater-than-50% decrease in RRF during follow-up. In multivariate analysis, only baseline PAD, Ca×P, and peritonitis were independently associated with a decline in RRF.♦ Conclusions: Our study suggests that PAD may be a clinically important marker of CVD predicting the loss of RRF. It remains to be determined whether interventions aimed at decreasing PAD may also improve renal vascular status and thus slow the rate of RRF decline.     

Urinary biomarkers in septic acute kidney injury

Objective To appraise the literature on the value of urinary biomarkers in septic acute kidney injury (AKI). Design Systematic review. Setting Academic medical centre. Patients and participants Human studies of urinary biomarkers. Interventions None. Measurements and results Fourteen articles fulfilled inclusion criteria. Most studies were small, single-centre, and included mixed medical/surgical adult populations. Few focused solely on septic AKI and all had notable limitations. Retrieved articles included data on low-molecular-weight proteins (β₂-microglobulin, α₁-microglobulin, adenosine deaminase binding protein, retinol binding protein, cystatin C, renal tubular epithelial antigen-1), enzymes (N-acetyl-β-glucosaminidase, alanine-aminopeptidase, alkaline phosphatase; lactate dehydrogenase, α/π-glutathione-S-transferase, γ-glutamyl transpeptidase), cytokines [platelet activating factor (PAF), interleukin-18 (IL-18)] and other biomarkers [kidney injury molecule-1, Na/H exchanger isoform-3 (NHE3)]. Increased PAF, IL-18, and NHE3 were detected early in septic AKI and preceded overt kidney failure. Several additional biomarkers were evident early in AKI; however, their diagnostic value in sepsis remains unknown. In one study, IL-18 excretion was higher in septic than in non-septic AKI. IL-18 also predicted deterioration in kidney function, with increased values preceding clinically significant kidney failure by 24–48 h. Detection of cystatin C, α₁-microglobulin, and IL-18 predicted need for renal replacement therapy (RRT). Conclusions Few clinical studies of urinary biomarkers in AKI have included septic patients. However, there is promising evidence that selected biomarkers may aid in the early detection of AKI in sepsis and may have value for predicting subsequent deterioration in kidney function. Additional prospective studies are needed to accurately describe their diagnostic and prognostic value in septic AKI.     

静滴甘露醇致急性肾功能损害的观察护理

回顾分析 1989年 5月～ 1998年 12月所遇 2 1例静滴甘露醇致急性肾功能损害病例。要防止甘露醇对肾功能的急性损害 ,须 :(1)甘露醇的应用应因人而异、剂量适当、速度相宜 ;(2 )避免合用肾毒性药物 ;(3)密切关注尿量、尿常规及肾功能的轻微变化 ;(4 )加强预见性护理 ,出现急性肾功能损害 ,应及时停用甘露醇 ,采取有效救治措施     

左西孟旦对重症瓣膜病术后肾功能的影响

目的:观察重症瓣膜病患者术后使用左西孟旦对肾功能的影响。方法:2012年12月至2014年9月术后使用左西孟旦的重症瓣膜病患者36例为治疗组,2011年10月至2012年12月术后未使用左西孟旦的重症瓣膜病患者36例为对照组,记录两组术前(T1)、术后返回ICU(T2)、术后24 h(T3)、术后3 d(T4)、术后7 d(T5)的血尿素氮(BUN)、血肌酐值(Cr)、肌酐清除率(Ccr)、ICU停留时间、术后住院时间及发生急性肾损伤(AKI)、使用肾脏替代治疗(CRRT)例数。结果:两组Ccr在T3(P=0.02)、T4(P=0.008)有明显差异;BUN在T2(P=0.03)、T3(P=0.01)、T4(P=0.007)有明显差异;两组AKI发生率(P=0.003)、CRRT使用率(P=0.01)、ICU停留时间(P=0.0008)和术后住院时间(P=0.007)均有明显差异。结论:重症瓣膜病患者术后使用左西孟旦可有效改善肾脏功能,降低术后AKI发生率及CRRT使用率,减少ICU和术后住院时间。     

Effect of Biocompatible Peritoneal Dialysis Solution on Residual Renal Function: A Systematic Review of Randomized Controlled Trials

♦ Introduction: Residual renal function (RRF) plays an important role in outcome of peritoneal dialysis (PD) including mortality. It is, therefore, important to provide a strategy for the preservation of RRF. The objective of this study was to evaluate relative protective effects of new glucose-based multicompartmental PD solution (PDS), which is well known to be more biocompatible than glucose-based conventional PDS, on RRF compared to conventional PDS by performing a systematic review (SR) of randomized controlled trials.♦ Methods: We searched studies presented up to January 2014 in MEDLINE, EMBASE, the COCHRANE library, and local databases. Three independent reviewers reviewed and extracted prespecified data from each study. The random effects model, a more conservative analysis model, was used to combine trials and to perform stratified analyses based on the duration of follow-up. Study quality was assessed using the Cochrane Handbook for risk of bias. Eleven articles with 1,034 patients were identified for the SR.♦ Results: The heterogeneity of the studies under 12 months was very high, and the heterogeneity decreased substantially when we stratified studies by the duration of follow-up. The mean difference of the studies after 12 months was 0.46 mL/min/1.73 m² (95% confidence interval = 0.25 to + 0.67).♦ Conclusion: New PDS showed the effect to preserve and improve RRF for long-term use compared to conventional PDS, even though it did not show a significant difference to preserve RRF for short-term use.     

Predicting the risk of postoperative acute kidney injury: development and assessment of a novel predictive nomogram

ObjectiveThis study aimed to establish and internally verify the risk nomogram of postoperative acute kidney injury (AKI) in patients with renal cell carcinoma.MethodsWe retrospectively collected data from 559 patients with renal cell carcinoma from June 2016 to May 2019 and established a prediction model. Twenty-six clinical variables were examined by least absolute shrinkage and selection operator regression analysis, and variables related to postoperative AKI were determined. The prediction model was established by multiple logistic regression analysis. Decision curve analysis was conducted to evaluate the nomogram.ResultsIndependent predictors of postoperative AKI were smoking, hypertension, surgical time, blood glucose, blood uric acid, alanine aminotransferase, estimated glomerular filtration rate, and radical nephrectomy. The C index of the nomogram was 0.825 (0.790–0.860) and 0.814 was still obtained in the internal validation. The nomogram had better clinical benefit when the intervention was decided at the threshold probabilities of >4% and <79% for patients and doctors, respectively.ConclusionsThis novel postoperative AKI nomogram incorporating smoking, hypertension, the surgical time, blood glucose, blood uric acid, alanine aminotransferase, the estimated glomerular filtration rate, and radical nephrectomy is convenient for facilitating the individual postoperative risk prediction of AKI in patients with renal cell carcinoma.     

超声造影评估脊髓损伤并发肾积水患者肾功能的价值

目的 探讨超声造影评价脊髓损伤并发肾积水患者肾功能的临床价值。方法 2015年10月至2018年11月,选择脊髓损伤并发肾积水并且肾功能下降患者23例(脊髓损伤组)和健康志愿者19例(对照组),双肾进行超声造影检查并与肾动态显像结果进行对照分析。利用软件分析采集的超声造影图像,在肾皮质选取感兴趣区(ROI),绘制时间强度曲线。以达峰时间(TTP)、峰值强度(DPI)、上升支斜率(A)和曲线下面积(AUC)为自变量,肾动态显像结果为因变量做Logistics回归,再进行ROC曲线分析。结果 两组血肌酐和尿素比较均无显著性差异(P> 0.05)。脊髓损伤组TTP显著长于对照组(t = 5.068, P < 0.001),A和AUC明显低于对照组( t > 3.784, P < 0.01)。AUC是肾功能损伤的影响因素( P <0.01)。AUC越小,肾损伤的可能性越大,敏感性和特异性之和最大为1.759,对应的AUC为982.518 dBs。结论 超声造影可以评价脊髓损伤并发肾积水患者肾功能。时间强度曲线AUC减小,提示肾功能受损。     

阿拓木兰在甘露醇治疗脑出血中的护肾作用

目的观察阿拓木兰在脑出血应用甘露醇脱水中对肾功能的保护作用。方法302例脑出血病人分为阿拓木兰组(A组,n=150)和对照组(B组,n=152),均用甘露醇脱水,治疗前后检查血肌酐水平,肌酐>97.5μmol/L为有肾功能损害。结果阿拓木兰组中出现肾功能损害为6.67%,对照组肾功能损害为21.05%(P<0.01)。结论脑出血病人用甘露醇脱水的同时使用阿拓木兰,有肾功能保护作用。     

联合检测尿NGAL、KIM-1对危重患儿急性肾损伤的临床意义

目的:探讨联合检测尿NGAL、KIM-1在判断重症患儿急性肾损伤(AKI)病情及预后中的作用。方法:以我院肾内科、PICU和健康体检儿童为观察对象,分为重症AKI组,重症非AKI组,CKD组和健康对照组,比较各组的血肌酐(sCr)和尿NGAL、尿KIM-1水平。结果:重症AKI组尿NGAL、KIM-1较重症非AKI组、CKD组、健康对照组明显升高(P0.05),重症非AKI组、CKD组、健康对照组各组间差别无统计学意义(P0.05)。尿KIM-1联合尿NGAL的峰值升高倍数和肾预后呈正相关,和CCr呈负相关关系。结论:尿NGAL和尿KIM-1水平与重症患儿AFI严重程度及肾预后有关。