肾衰合剂对维持性腹膜透析患者残余肾功能的影响

目的：观察肾衰舍剂对连续不卧床腹膜透析（CAPD）患者残余肾功能的影响，探讨中药治疗对CAPD患者残余肾功能的保护作用及其机制。方法：将56例脾肾气（阳）虚型的CAPD患者随机分为常规腹膜透析对照组，及加服中药肾衰合剂治疗组。治疗6个月，比较残余肾KT／V、残余肾CCr的变化及下降速率。结果：在维持总体透析效能的前提下，治疗组残余肾KT／V、残余肾CCr下降速度较对照组明显缓慢。结论：肾衰合荆能有效延缓PD患者的RRF的下降。     

The impact of residual renal function and total body water volume on achieving adequate dialysis in CAPD.

AIMS: The objective is to evaluate the impact of residual renal function (RRF) and total body water (TBW) on achieving adequate dialysis. METHODS: Sixty three CAPD patients performing four 2 liter exchanges daily were evaluated for RRF, total weekly Kt/V (TWKt/V), total weekly creatinine clearance (TWCC) and TBW. RESULTS: In patients with residual renal function (N = 41), TWKt/V and TWCC were 2.2 +/- 0.8 and 77.4 +/- 24.5 L, respectively. In patients without RRF (N = 22), TWKt/V was 1.6 +/- 0.4 and TWCC 42.6 +/- 9.2 L. TBW correlated negatively with TWKt/V in the group without RRF (r = -0.75, P<0.001). CONCLUSION: It is not possible for larger patients without RRF treated with CAPD (2L x 4 exchanges) to achieve the acceptable targets for TWKt/V and TWCC due to TBW.     

持续非卧床腹膜透析患者血清肌酐水平的影响因素分析

目的：探讨影响持续非卧床腹膜透析（CAPD）患者血清肌酐水平的因素。方法：选取北京大学第三医院腹透中心200名临床情况稳定的CAPD患者为研究对象。同时收集患者人口学特征、血清肌酐（Scr）及其他生化资料,评估腹膜透析充分性,采用简单相关及多元回归分析探讨影响Scr水平的因素。结果：所有患者平均年龄（61.02±14.81）岁,平均Scr（893±293）μmol/L;简单相关分析显示Scr水平与年龄、总尿素清除指数（TKt/V）、残肾尿素清除指数（RKt/V）、总肌酐清除率（Tccr）及残肾肌酐清除率（Rccr）呈负相关,而与透析剂量、体质指数（BMI）、透析龄呈正相关,差异均具有统计学意义;逐步多元回归分析提示在矫正透析剂量、透析龄及糖尿病等因素后,性别、年龄、Tccr、RKt/V、透析液肌酐浓度/血肌酐浓度（D/PCr）及BMI是影响Scr水平的独立因素（R2=0.659,P〈0.05）。结论：本研究提示在剂量、透析龄及糖尿病等因素后,性别、年龄、营养状况、残余肾功能及腹膜转运功能仍能独立地影响CAPD患者血清肌酐水平。     

Independent effects of residual renal function and dialysis adequacy on actual dietary protein, calorie, and other nutrient intake in patients on continuous ambulatory peritoneal dialysis.

Previous studies have suggested that the cross-sectional relationship observed between total solute clearance (Kt/V) and dietary protein intake (DPI) in patients undergoing dialysis is possibly mathematical in origin. A cross-sectional study on 242 patients undergoing continuous ambulatory peritoneal dialysis (CAPD) was performed to determine the differential effects of dialysis adequacy and residual renal function (RRF) on actual dietary intake. All patients underwent a 7-d food frequency questionnaire to quantify daily dietary protein, calorie (DCI), and other nutrient intake, subjective global assessment (SGA), and collection of 24-h dialysate and urine for total (PD and renal) Kt/V and RRF. Patients were categorized into three groups: I (n = 94), total Kt/V >/=1.7 and GFR >0.5 ml/min per 1.73 m(2); II (n = 58), total Kt/V >/=1.7 but GFR <0.5 ml/min per 1.73 m(2); and III (n = 90), total Kt/V <1.7. Sixty-nine percent versus 62% versus 42% of group I versus II versus III patients were well nourished according to SGA (P = 0.004). DPI (1.23 [0.47] versus 1.12 [0.49] versus 0.99 [0.40] g/kg per d; P = 0.002) and DCI (27.3 [8.9] versus 23.8 [8.6] versus 23.0 [8.2] kcal/kg per d; P = 0.002) showed significant decline across the three groups. Intake of other nutrients, including carbohydrate, fat, fatty acids, and cholesterol was higher for group I compared with groups II and III. Adjusting for age, gender, weight, and diabetes, every 1 ml/min per 1.73 m(2) increase in GFR was associated with a 0.838-fold increase in DCI (95% confidence interval to interval, 0.279 to 1.397; P = 0.003) and a 0.041-fold increase in DPI (95% confidence interval, 0.009 to 0.072; P = 0.012), whereas every 0.25-unit increase in total (PD and renal) Kt/V was associated with a 0.570-fold increase in DCI (95% confidence interval, 0.049 to 1.092; P = 0.032) and a 0.052-fold increase in DPI (95% confidence interval, 0.023 to 0.081; P = 0.001). Greater small-solute clearances are associated with better dietary intake and better nutrition. The study confirmed significant and independent effect of RRF, but not PD solute clearance, on actual DPI, DCI, and other nutrient intake in patients on CAPD.     

A novel association between residual renal function and left ventricular hypertrophy in peritoneal dialysis patients

BACKGROUND: Left ventricular hypertrophy (LVH) and dialysis adequacy are both important predictors for mortality in dialysis patients. This study evaluated the association between residual renal function (RRF) and the severity of LVH in endstage renal failure (ESRF) patients undergoing long-term continuous ambulatory peritoneal dialysis (CAPD). METHODS: A cross-section study was performed with left ventricular mass index (LVMi), determined in 158 non-diabetic CAPD patients using echocardiography and its relationship with residual glomerular filtration rate (GFR), peritoneal dialysis (PD) and total weekly urea clearance (Kt/V) and other known risk factors for LVH was evaluated. RESULTS: Twelve patients had no LVH (group I). The remaining 146 patients were stratified [group II (lowest), III and IV (highest)] according to the LVMi (median 207 g/m2; range 103 to 512 g/m2). Across the four groups of patients with increasing LVMi, there was significant decline in GFR (2.27 +/- 1.98 vs. 1.49 +/- 1.58 vs. 1.61 +/- 1.91 vs. 0.80 +/- 1.42 mL/min/1.73 m2; P = 0.011) and total weekly Kt/V (1.98 +/- 0.44 vs. 1.96 +/- 0.38 vs. 1.92 +/- 0.42 vs. 1.71 +/- 0.42; P = 0.037); however, PD Kt/V was similar for all four groups. Patients with better-preserved residual GFR not only had significantly higher total Kt/V, but were less anemic and hypoalbuminemic and had a trend toward lower systolic blood pressure and arterial pulse pressure. Multiple regression analysis showed that other than age, gender, body weight, arterial pulse pressure, hemoglobin and serum albumin, known factors for LVH, residual GFR (estimated mean -7.94; 95% confidence interval -15.13 to -0.74; P = 0.031) was also independently associated with LVMi. CONCLUSIONS: Other than anemia, hypoalbuminemia and arterial pulse pressure, this study demonstrates an important, novel association between the degree of RRF and severity of LVH in ESRF patients undergoing long-term CAPD. Prospective studies are needed to define if indeed there is a cause-effect relationship between this association, to evaluate if a decline in residual GFR is independently associated with an increase in LVMi, and to determine whether treatment directed at preserving RRF will reduce the severity of LVH, improve cardiac performance and hence survival of these patients.     

Kinetic modelling and underdialysis in CAPD patients

Kinetic analysis was performed in all 58 patients undergoingstandard CAPD. The urea distribution volume was estimated fromanthropomorphic measurements (Watson formulae). Normalized proteincatabolic rate (NPCR), daily protein leak (PL), urea and creatinineKt/Vs, clearances and peritoneal mass transfer coefficients(Kp) were calculated from measurements on serum, 24-h urineand PD fluid effluent. The mean total (renal+PD) daily creatinine and urea Kt/Vs (KT/V)were 0.31 (range 0.15–0.79) and 0.31 (0.18/0.65). Therewas no relationship between KT/V and serum urea or Kp. The strongestdeterminant of the urea KT/V was the residual renal urea clearance(KrU)(R=079, P<0.001) which decreased with time on dialysis(R=–0.38, P<0.005). There was a significant correlationbetween the hospital admissions per year and both the urea andcreatinine KT/V and KrU (R=–0.30, –0.32, P<0.05).Patients with urea KT/V<0.25 (n=22) had more hospital admissions/yearthan those with KT/V>0.25 (mean of 2.6 versus 1.5, P<0.05).NPCR correlated with urea KT/V (R=0.62, P<0.001) but notwith serum albumin or the PL. Patients identified by UKM to be less well dialysed have a lowerresidual renal function and are more likely to be hospitalized.Undernutrition in CAPD patients appears to be related to underdialysisrather than protein loss.     

Importance of residual renal function in continuous ambulatory peritoneal dialysis: its influence on different parameters of renal replacement treatment.

OBJECTIVE: To study the influence of residual renal function (RRF) on different parameters of the renal substitutive treatment offered by peritoneal dialysis. METHODS: We analyzed the impact of RRF on dialysis dose, nutrition parameters, anemia and phosphocalcic metabolism in 37 patients with end-stage renal disease (ESRD) treated by continuous ambulatory peritoneal dialysis (CAPD). Analytical controls were done every 6 months after an initial assessment at the end of the first month of treatment. Multiple lineal regression models were used as the statistical method to analyze the influence of RRF on different theoretically dependent factors. RRF was calculated as a mean of creatinine and urea clearances. Three observations per patient were used: one at the end of the first month of treatment; a final one at the end of follow-up (mean time 24.2 +/- 11.4 months), and at a mean time between them (13.4 +/- 6.7 months), with a final number of 111 observations. RESULTS: Dialysis dose: RRF was the most important factor in terms of creatinine clearance (r(2) = 0.94; beta = 0.999), KT/V (r(2) = 0. 68; beta = 0.819) and beta(2)-microglobulin levels (r(2) = 0.46; beta = -0.489). Nutrition parameters: RRF was a determinant factor for normalized protein catabolic rate (r(2) = 0.53; beta = 0.471), percent lean body mass (r(2) = 0.45; beta = 0.446) and albumin levels (r(2) = 0.25; beta = 0.229). Anemia: RRF was the most important factor when studying hemoglobin levels (r(2) = 0.28; beta = 0.407). Phosphocalcic metabolism: Between the analyzed factors, RRF was the only one which reached significance on serum phosphate levels (r(2) = 0.19; beta = -0.594). RRF did not show any relationship with either calcium or PTH levels. CONCLUSIONS: Independent of other factors, RRF in CAPD is positively and directly related to dialysis dose, beta(2)-microglobulin levels, nutrition parameters (albumin, normalized protein catabolic rate and percent lean body mass, hemoglobin and serum phosphate levels.     

Cystatin C as marker of residual renal function in patients on peritoneal dialysis: relation with parameters of peritoneal function

INTRODUCTION: Cystatin C (CysC) is a nonglycosylated protein of low molecular weight not influenced by age, sex or inflammation. The aim of this paper is to ascertain the usefulness of serum CysC level determination in peritoneal dialysis (PD) patients. MATERIAL AND METHODS: CysC serum levels were determined in 80 PD patients. The mean age of patients was 53.7 +/- 15 years, with 15.3 +/- 25.8 months on PD. Thirty-three percent were on continuous ambulatory peritoneal dialysis (CAPD) and 66.3% on automated peritoneal dialysis (APD). Fourteen patients (17%) had no residual renal function (RRF). RESULTS: Mean CysC levels were 5.8 +/- 1.4 mg/L, without differences between men (5.5 +/- 1.4 mg/L) and women (5.6 +/- 1.5 mg/L, NS). There was no correlation between CysC levels and age, weight, height or time on PD. Anuric patients had CysC levels significantly higher than non-anuric (6.7 +/- 1.4 vs. 5.3 +/- 1.3 mg/L, p<0.001). CysC levels showed an inverse correlation with RRF (r=-0.60, p<0.001) and residual urine volume (r=-0.58, p<0.001). CONCLUSIONS: In conclusion, serum CysC levels had the same statistical significance as plasma creatinine levels, and they are not influenced by peritoneal transport in PD patients. Consequently, both parameters are valid RRF markers.     

小剂量日间非卧床腹膜透析对残肾功能较好的糖尿病终末期肾病患者的疗效

目的　研究小剂量日间非卧床腹膜透析（DAPD）和小剂量持续非卧床腹膜透析（CAPD）对残肾功能较好的糖尿病终末期肾病（ESRD）患者的疗效。 方法 病情稳定、残肾功能较好（rGFR≥5 ml/min,且尿量≥750 ml/d）的40例糖尿病ESRD患者入选。按数字随机法分为小剂量DAPD组20例和小剂量CAPD组20例。DAPD组透析处方为1.5 L或2 L,3次/d,每次留腹3～4 h,夜间干腹。CAPD组透析处方为1.5～2 Ｌ,3次/d,或1.5 L,4次/d,夜间留腹。在研究开始及6个月后,分别计算两组腹膜尿素氮清除率（Kt/V）、残肾Kt/V、每周总Ｋt/V、Ccr、rGFR等指标;测定24 h尿蛋白量、24 h腹透液蛋白、血清白蛋白、空腹血糖、糖化血红蛋白及胰岛素剂量;用改良主观综合性营养评估法（SGA）评估患者营养状况。 结果 共35例患者完成研究。两组患者年龄、性别、体质量指数、透析龄、透析液肌酐/血肌酐（D/Pcr）等基线值差异无统计学意义。6个月后,CAPD组胰岛素剂量和24 h腹透液丢失蛋白明显高于DAPD组,分别为（33.6±10.9） U/d 比（20.6±6.2） U/d（P < 0.05）和（11.13±4.95） g比（5.66±2.88） g（P < 0.01）,而血清白蛋白明显低于DAPD组[（29.7±4.2） 比（36.5±3.9） g/L,P < 0.05]。DAPD组与CAPD组相比,24 h净超滤量为（554±187） ml比（309±177） ml,24 h尿量为（1090±361） ml比（750±258） ml,rGFR为（8.21±2.40） ml/min比（4.88±2.11） ml/min,DAPD组均显著高于CAPD组（均P < 0.05）。 结论 对于残肾功能较好的糖尿病ESRD患者,小剂量DAPD较小剂量CAPD能更好地控制血糖,改善营养状态及保护残肾功能。     

The contribution of residual renal function to overall nutritional status in chronic haemodialysis patients.

BACKGROUND: The benefits of residual renal function (RRF) in peritoneal dialysis patients have been described frequently. However, previous reports have shown that RRF diminished faster in haemodialysis (HD) patients than in peritoneal dialysis patients, and in most of the studies in HD patients, RRF was ignored. In this study, the RRF in chronic HD patients was studied to assess its impact on patients' nutritional status. METHODS: In 41 chronic HD patients with at least a 2-year history of HD treatment, RRF was determined by a urine collection for 7 consecutive days. Nutritional parameters, such as percentage body fat, fat-free mass index, serum albumin concentration and normalized protein catabolic rate, were also measured. RESULTS: In all 41 patients, mean weekly total Kt/V urea was 4.88 and renal Kt/V urea was 0.65. RRF was well correlated with serum albumin concentration, but dialysis Kt/V urea was not. One year after the start of this study, RRF and nutritional indices were re-examined and patients were classified into two groups: with RRF, preserved residual renal diuresis over 200 ml/day (mean, 720 ml; range, 230-1640 ml), N=23; and without RRF, persistent anuria (mean, 51 ml; range, 0-190 ml), N=18. At the start of this study, the mean serum albumin concentration and mean normalized protein catabolic rate in patients with RRF were 3.84 g/dl and 1.16 g/kg/day, respectively, which were significantly higher than those in patients without RRF (P=0.02 and P=0.0002, respectively), despite total (renal+dialysis) Kt/V urea being equal in both groups. During the 1-year study period, there was no significant change in total Kt/V urea in either group. Mean serum albumin concentration increased to 4.05 g/dl in patients with RRF, but did not change significantly (from 3.66 to 3.62 g/dl) in patients without RRF. The same trend was observed in all other parameters. CONCLUSION: Over half of our HD patients had sufficient RRF. RRF itself may have a beneficial effect on nutritional parameters, and it is important to determine RRF over time, even in chronic HD patients.     

Reduced residual renal function is a risk of peritonitis in continuous ambulatory peritoneal dialysis patients.

BACKGROUND: Loss of residual renal function (RRF) contributes to anaemia, inflammation and malnutrition and is also a strong predictor of mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. However, the role of RRF on peritonitis is not yet clearly established. This study aimed to evaluate the effect of RRF on the development of peritonitis. METHODS: Study subjects were 204 end-stage renal disease (ESRD) patients who started PD from January 2000 to December 2005. Biochemical and clinical data within 1 month of PD commencement were considered as baseline. To determine risk factors for peritonitis, multivariate Cox regression was performed. Kaplan-Meier analysis and log-rank test were used to examine the difference of peritonitis-free period according to the presence of diabetes and RRF. RESULTS: On univariate analysis based on baseline data in first peritonitis, diabetes was less prevalent and RRF (6.7+/-2.6 vs 4.0+/-2.3 ml/min/1.73 m2, P<0.01), haemoglobin (10.9+/-1.2 vs 10.6+/-1.2 g/dl, P<0.05) and serum albumin level (3.6+/-0.4 vs 3.4+/-0.4 g/dl, P<0.01) were significantly higher in the peritonitis-free group. Kaplan-Meier analysis showed that time to first PD peritonitis episode was significantly longer in the non-diabetic patients (P<0.001) and in patients with higher residual GFR (P<0.001). Multivariate analysis showed that diabetes [hazard ratio(HR) 1.64, P<0.05] and RRF (per 1 ml/min/1.73 m2 increase, HR 0.81, P<0.01) were independent risk factors. CONCLUSION: Our study revealed that RRF and diabetes were risk factors for peritonitis. These results suggest that preservation of RRF should be viewed as a protective strategy to reduce peritonitis.     

A longitudinal, five year survey of urea kinetic parameters in CAPD patients.

This study reports on the five years' evolution of the KT/V urea index and protein catabolic rate (PCR) in 16 CAPD patients who were treated with a constant daily dialysis dose. Total KT/V urea index decreased with time from a value of 0.96 +/- 0.06 at the start to 0.55 +/- 0.05 at five years of treatment. This decline was due to the opposite changes of two important parameters affecting the index. First, the contribution of the residual urinary KT/V gradually decreased from 28.6% at the start to 8 to 9% after four years. Second, the distribution volume of urea calculated as a constant fraction of body weight gradually increased. The body weight increased from 58.2 +/- 2.79 kg at start to 70.6 +/- 3.33 kg at five years. Peritoneal urea clearances and ultrafiltration rates remained stable. In 12 patients with stable body weight between 24 and 48 months, PCR decreased from 0.98 +/- 0.05 to 0.87 +/- 0.05 g/kg/day. A positive correlation between KT/V urea and PCR and a negative correlation between KT/V urea and number of hospitalization days, peritonitis rates and peripheral nerve conductivity was found. The same negative correlation was found when only the KT/V urea index obtained during the first year of treatment was considered. In conclusion, the KT/V urea index decreases in CAPD patients primarily because residual renal function decreases and body weight increases, while the peritoneal clearing for urea is maintained. The index correlates with some clinical parameters, and may have some prognostic value.     

Important differentiation of factors that predict outcome in peritoneal dialysis patients with different degrees of residual renal function.

BACKGROUND: Residual renal function (RRF) is an important predictor of outcome in peritoneal dialysis (PD) patients. Whether results from survival studies in dialysis patients with RRF can also be extrapolated to anuric patients remains uncertain. In this observational study, we examined the characteristics of PD patients with a residual glomerular filtration rate (GFR) > or =1 ml/min per 1.73 m2 vs those with complete anuria and differentiated factors that predict outcome in the two groups of patients. METHODS: Two hundred and forty-six continuous ambulatory peritoneal dialysis (CAPD) patients (39% being completely anuric) were recruited from a single regional dialysis centre. Assessments of haemodynamic, echocardiographic, nutritional and biochemical parameters and indices of dialysis adequacy were done at study baseline and were related to outcomes. RESULTS: During the prospective follow-up of 30.8+/-13.8 (mean+/-SD) months, 28.0% of patients with residual GFR > or =1 ml/min per 1.73 m2 vs 50.5% of anuric patients had died (P = 0.005). The overall 2 year patient survival was 89.7 and 65.0% for patients with GFR > or =1 ml/min per 1.73 m2 and anuric patients, respectively (P = 0.0012). Compared with patients with GFR > or =1 ml/min per 1.73 m2, anuric patients were dialysed for longer (P<0.001), were more anaemic (P<0.005), and had higher calcium-phosphorus product (P<0.01), higher C-reactive protein (P<0.001), lower serum albumin (P<0.05), greater prevalence of malnutrition according to subjective global assessment (P<0.05) and more severe cardiac hypertrophy (P<0.001) at baseline. Using multivariable Cox regression analysis, serum albumin, left ventricular mass index and residual GFR were significant factors associated with mortality in patients with GFR > or =1 ml/min per 1.73 m2, while increasing age, atherosclerotic vascular disease and higher C-reactive protein were associated with greater mortality in anuric PD patients. CONCLUSIONS: Our study demonstrates more adverse cardiovascular, inflammatory, nutritional and metabolic profiles as well as higher mortality in anuric PD patients. Furthermore, factors associated with mortality are also not equivalent for PD patients with and without RRF, suggesting that patients with and without RRF are qualitatively different.     

Incremental peritoneal dialysis: effects on the choice of dialysis modality, residual renal function and adequacy

There is still disagreement on whether peritoneal dialysis (PD) should begin with a full dose (Full_Dial) or with incremental doses (Incr_Dial) to compensate for the amount of Kt/V no longer supplied by the residual renal function (RRF). The aim of this study is to assess the effects of an Incr_Dial protocol on the choice of dialysis modality, RRF, and adequacy. The Incr_Dial protocol in our center is as follows: for patients with a glomerular filtration rate (GFR)>5 ml min(-1), PD is initiated with two exchanges per day (continuous ambulatory PD (CAPD)) or four sessions per week (ambulatory PD (APD)); and hemodialysis (HD) is initiated with two sessions per week. The PD dose is then increased in proportion to the reduction in the GFR as follows: GFR< or =5 and >3 ml min(-1)=3 CAPD exchanges or five APD sessions; GFR <3 ml min(-1)=full dialysis dose (Full_Dial). The effects of the Incr_Dial protocol on the choice of dialysis modality were assessed on 87 patients (pts) (age: 69.3+/-13.1 years) who initiated dialysis between 1 January 2004 and 31 May 2007. The effects of Incr_Dial on RRF and dialytic adequacy were assessed in 11 pts treated with two CAPD exchanges per day for a total of 106 months (mean+/-s.d. 9.7+/-6.5), and then treated with three CAPD exchanges per day for an additional 105 months (9.4+/-8.3). The use of Incr_Dial determined the choice of PD in 27 of 44 pts (61.4%) without indications or contraindications to HD or PD. CAPD was chosen by 20 of these pts (74.1%), whereas APD was preferred by 6 of the 8 pts switched from Incr_Dial to Full_Dial. During Incr_Dial, a significant reduction in the loss of GFR of 2.4+/-3.1 ml min(-1) year(-1) was observed when compared to the pre-dialysis period. Incr_Dial allowed for adequate clearance, as confirmed by the Kt/V (2.07+/-0.2), protein nitrogen appearance (1.17+/-0.13), and biochemical parameters. Ultrafiltration (UF) with icodextrin (772+/-166 ml per exchange) provided a daily UF of 517+/-296 ml day(-1) and remained unchanged when the duration of the dwell time increased significantly from 12.3+/-1.4 to 17.5+/-2.6 h.     

高血脂对腹膜透析患者的残余肾功能影响

目的：观察高血脂对连续性不卧床腹膜透析（CAPD）患者的残余肾功能（RRF）的作用。方法：定期监测共72例CAPD患者血脂成分及残余肾功能,根据血脂的变化将患者分为胆固醇（TC）增高组、三酰甘油（TG）增高组及二者均增高组与TC、TG正常组,比较各组残余肾功能变化。结果：CAPD治疗初期残余肾功能无明显变化（P〉0.05）。第12月时,TC增高组RRF较同组透析初月时下降（P〈0.05）。TG增高组及TC、TG均增高组的RRF分别与透析初月时同组RRF比较显著下降（P〈0.001）。第18月时3个血脂增高组RRF与TC、TG组比较均有下降（P〈0.05）。RRF下降数值与TC（r=0.234,P〈0.05）、TG（r=0.528,P〈0.05）均呈正相关。结论：CAPD患者的RRF随着透析时间的延长而降低。高血脂与RRF改变值有正相关性。     

Residual Daily Urine Volume Association with Inflammation and Nutrition Status in Maintenance Hemodialysis Patients

Background. This study determines the clinical significance of residual renal function (RRF), defined as residual daily urine volume (RDUV), in maintenance hemodialysis (MHD) patients. Methods. This multi-center study enrolled 704 MHD patients. Geographic, hematological, biochemical, and dialysis-related data were obtained. Values for nutritional and inflammatory markers were analyzed together with RDUV. Results. In total, 670 of 704 patients (95.2%) with HD duration greater than 1 year had abnormal RDUV (<500 ml). Patients with higher RRF were younger, had shorter HD duration, higher prevalence of hypertension and levels of serum albumin, high density lipoprotein (HDL), and lower mid-week inter-dialysis body weight increase (MIBWI), cardio-thoracic ratio, levels of intact parathyroid hormone, high sensitivity C-reactive protein (Hs CRP), and KT/V (Daugirdes) values than those with low RRF. Stepwise multiple regression analysis demonstrated that RRF was positively correlated with serum albumin, HDL levels, and presence of hypertension, and negatively correlated with age, HD duration, and MIBWI in MHD patients. Moreover, after adjusting factors that were significantly related to serum albumin or Hs CRP, RRF was still positively correlated with serum albumin (0.000137 ± 0.000585, p?=?0.0197) and negatively correlated with log Hs CRP (?0.000184 ± 0.000952, p = 0.0533). A one-liter increase in RDUV was associated with a 1.4 g/L increase in serum albumin level in MHD patients. Conclusion. This clinical study first demonstrated that RRF affects nutritional and inflammatory status in MHD patients. Because malnutrition and inflammation can cause high mortality in MHD patients, preserving RRF is important for these patients.     

Validation of cystatin C-based equations for evaluation of residual renal function among patients undergoing continuous ambulatory peritoneal dialysis

Objective To validate cystatin (Cys C)-based equations for evaluation of residual renal function （RRF） in patients on continuous ambulatory peritoneal dialysis (CAPD). Methods Fifty patients on CAPD from our department were enrolled in the study. Eight patients with residual urine volume ≤100 ml/d and 42 patients with residual urine volume ＞100 ml/d were enrolled into anuria group and non-anuric group respectively. The clinical and laboratory status of each group were compared and equations (Hoek’s, Yang’s and abbreviated MDRD equations) were validated in the non-anuric group by comparing with the arithmetic average of residual renal creatinine clearance rate and residual renal urea clearance rate which was considered as the golden standard for RRF. Results (1) Anuric group had significantly higher serum Cys C than the non-anuric group [(7.73±1.13) mg/L vs (6.46±1.15) mg/L, t＝2.39, P＝0.02)]. (2) RRF estimated by each equation was correlated well with measured RRF (r＝0.56, 0.56 and 0.39, all P＜0.05). (3) Yang’s equation [0.10 ml•min-1•(1.73 m2)-1] was least biased, followed by Hoek’s equation [-0.73 ml•min-1•(1.73 m2)-1] and abbreviated MDRD equation [3.15 ml•min-1•(1.73 m2)-1]. (4) The precision of Yang’s equation was equivalent to that of Hoek’s equation and both of them were better than abbreviated MDRD equation [6.2 and 6.1 vs 8.4 ml•min-1•(1.73 m2)-1]. (5) 50% accuracy according to Yang’s equation and Hoek’s equation revealed an elevated results in comparison to that according to abbreviated MDRD equation (59.5% and 54.8% vs 23.8%, respectively, all P＜0.01). Conclusions Serum Cys C-based prediction equations are better than the abbreviated MDRD equation in bias, precision and 50% accuracy. For patients undergoing CAPD, the use of Cys C-based equation to estimate RRF may be a clinically acceptable alternative.     

Does loss of residual renal function lead to malnutrition in peritoneal dialysis patients?

OBJECTIVES: It is usually believed that loss of residual renal function is associated with anorexia and the development of malnutrition. We conducted a retrospective study in our center to evaluate the effect of declining residual renal function on patients' nutritional status. METHODS: All incident uremic patients (n = 46) who began peritoneal dialysis from January 1, 2003 June 1, 2003 in our center were closely followed for 1 year with focus on maintaining strict volume control with time on dialysis. Patient's residual renal function (RRF) was assessed by the average renal urea and creatinine clearances. Those patients who had more than 50% decrease in GFR were selected for the present analysis. Serum albumin (ALB), dietary protein intake (DPI) and subjective global assessment (SGA) were closely followed. RESULTS: There were 16 patients (9 males and 7 females) included in the present analysis, among whom 31.3% were diabetics. Patients' GFR declined significantly (RRF were 4.32 +/- 2.69, 2.99 +/- 2.21 and 1.24 +/- 0.99 ml/min for Months 1, 6 and 12, respectively, p < 0.05), along with a significant decline in urine volume (985.62 +/- 543.29, 698.13 +/- 463.59 and 425.63 +/- 320.52 ml/d for Months 1, 6 and 12, respectively, p < 0.01). Although weekly peritoneal Kt/V did not increase significantly, peritoneal ultrafiltration increased significantly during this period (428.75 +/- 408.96, 534.38 +/- 296.39, 844.38 +/- 440.35 ml for Months 1, 6 and 12, respectively, p < 0.05). Serum ALB increased significantly (32.34 +/- 5.07, 34.74 +/- 4.89 and 36.21 +/- 3.98 g/l for Months 1, 6 and 12, respectively, p < 0.01). DPI also increased significantly. The prevalence of malnutrition (by SGA) decreased from 62.5% at the start of dialysis to 18.8% at the end of this study (p < 0.05). CONCLUSIONS: Our study suggests that rapid decline of residual renal function in PD patients does not necessarily lead to decreased dietary protein intake and deteriorated nutritional status. Focus on incremental peritoneal fluid removal along with the decline in residual renal function and, thus, maintaining volume control may be one of the critical reasons for the success.     

Peritoneal solute transport predicts survival on CAPD independently of residual renal function

Background: Loss of residual renal function has a profound effect on the survival of peritoneal dialysis patients. Less is known of the impact of peritoneal function. The purpose of this study was to investigate the influence of solute transport on clinical outcome in CAPD patients. Methods: Two hundred and ten consecutive patients commencing CAPD since 1990 were enrolled into a single centre prospective longitudinal observational study of urea, protein, and peritoneal kinetics. On entry, and at 6-monthly intervals, estimations were made of weight, body mass index (BMI), plasma albumin, Kt/V, residual renal function (RRF), NPCR, low-molecular-weight solute transport (D/Pcreat), and peritoneal protein losses. All patients were censored in 1996, regardless of treatment modality. Results: During the 6-year follow up period (median 22 months) there were 51 deaths, and the actuarial survival was 58% at 5 years. Urea, protein and peritoneal kinetics varied with time on dialysis: as anticipated there was a reduction in Kt/V, attributable to loss of RRF, whereas plasma albumin was stable for the first 2 years of treatment, but subsequently started to decline, a trend that became significant at 42 months. Peritoneal kinetics stabilized within the first 6 months of treatment and then showed a trend of increased solute transfer with time on treatment, which became significant by the end of the study. Comparing survivors with non-survivors Kt/V and RRF were similar at the start of treatment, but loss of RRF occurred significantly earlier in non-survivors than survivors (0.37vs 0.68, P=0.02 at 6 months, 0.19 vs 0.54, P=0.01 at 12 months). D/Pcreat was also identical at commencement of treatment, but subsequently whilst survivors had stable solute transfer non-survivors had consistently higher solute transfer beyond 6 months that reached increasing significance after 18 months, (0.70 vs 0.67, P=0.05 at 18 months, 0.72 vs 0.66, P=0.03 at 24 months). A Cox proportional hazard model constructed for the variables age, sex, BMI, albumin, Kt/V and D/Pcreat at 6 months of treatment indicated that low Kt/V (P=0.0004), high D/Pcreat (P=0.013) and age (P=0.028) were independent predictors of death. Conclusion: There is good reason to believe that high peritoneal solute transport is an independent marker of poor outcome in CAPD patients.     

The bacterial colonization in tunneled cuffed dialysis catheter and its effects on residual renal function in incident hemodialysis patients

Background

The bacterial colonization of hemodialysis catheter occurs frequently and reaches to the catheter-related bloodstream infections (CRBSIs). We hypothesized bacterial colonization promotes inflammation and that might be associated with renal outcome. The aim of this study was to investigate the colonization status for tunneled cuffed dialysis catheter (TCC) and the factors for contributing to the catheter colonization and explore whether bacterial colonization would be related with declining of residual renal function (RRF).

Methods

115 patients who received TCC removal operation and underwent catheter tip culture from January 2005 to June 2014 were enrolled. The follow-up data such as urine output (UO), time to anuria and patients’ survival were collected from the patients or their family members by telephone in June, 2014.

Results

There were nineteen patients (16.5 %, 19/115) with positive tip culture (colonization group). In the analysis of demographic and biochemical parameters, there were no significant differences between both groups. Fifty of all the subjects responded to the telephone survey and ten patients (20.0 %, 10/50) belonged to colonization group. The monthly decreasing rate of UO was significantly more rapid in colonization group (p = 0.001). The survival analysis showed that colonization group had worse estimated anuria-free survival than non-colonization group (p < 0.001). In multivariate cox regression, bacterial colonization of TCC was an independent factor influencing the loss of RRF (HR 4.29, 95 % CI: 1.905–9.683, p ≤ 0.001).

Conclusions

Bacterial colonization of TCC was associated with rapid loss of RRF.