Dialysate cancer antigen 125 in long-term peritoneal dialysis patients

Structural and functional peritoneal membrane changes are associated with long-term peritoneal dialysis. These changes can lead to ultrafiltration failure and peritoneal fibrosis, reducing the efficacy of the peritoneal membrane to remove waste and balance fluid and electrolytes. The loss of mesothelial cells from the basement membrane is one of the major characteristics in peritoneal membrane structural change. Thus, if the reduction of peritoneal mesothelial cell mass in peritoneal dialysis patients is monitored, signs of ultrafiltration failure and peritoneal fibrosis can be detected early. One of biomarkers that can be used to indicate the change in peritoneal mesothelial cell mass is CA125, which is produced by mesothelial cells. In this article, we review the measurement and clinical use of CA125 in peritoneal dialysate effluent. Additionally, we address the data and studies on the association between dialysate CA125 levels and factors related to ultrafiltration failure and peritoneal fibrosis, including the parameters used to monitor the functional status of the peritoneal membrane. Our review shows that dialysate CA125 can be used to evaluate the peritoneal membrane in noninfected patients to predict peritoneal fibrosis, and it can also be used as a biomarker of biocompatible dialysis solutions.     

Dialysate leaks in peritoneal dialysis

Dialysate leakage represents a major noninfectious complication of peritoneal dialysis (PD). An exit-site leak refers to the appearance of any moisture around the PD catheter identified as dialysate; however, the spectrum of dialysate leaks also includes any dialysate loss from the peritoneal cavity other than via the lumen of the catheter. The incidence of dialysate leakage is somewhat more than 5% in continuous ambulatory peritoneal dialysis (CAPD) patients, but this percentage probably underestimates the number of early leaks. The incidence of hydrothorax or pleural leak as a complication of PD remains unclear. Factors identified as potentially related to dialysate leakage are those related to the technique of PD catheter insertion, the way PD is initiated, and weakness of the abdominal wall. The pediatric literature tends to favor Tenckhoff catheters over other catheters as being superior with respect to dialysate leakage, but no consensus on catheter choice exists for adults in this regard. An association has been found between early leaks (< or =30 days) and immediate CAPD initiation and perhaps median catheter insertion. Risk factors contributing to abdominal weakness appear to predispose mostly to late leaks; one or more of them can generally be identified in the majority of patients. Early leakage most often manifests as a pericatheter leak. Late leaks may present more subtly with subcutaneous swelling and edema, weight gain, peripheral or genital edema, and apparent ultrafiltration failure. Dyspnea is the first clinical clue to the diagnosis of a pleural leak. Late leaks tend to develop during the first year of CAPD. The most widely used approach to determine the exact site of the leakage is with computed tomography after infusion of 2 L of dialysis fluid containing radiocontrast material. Treatments for dialysate leaks include surgical repair, temporary transfer to hemodialysis, lower dialysate volumes, and PD with a cycler. Recent recommendation propose a standard approach to the treatment of early and late dialysate leaks: 1-2 weeks of rest from CAPD, and surgery if recurrence. Surgical repair has been strongly suggested for leakage causing genital swelling. Delaying CAPD for 14 days after catheter insertion may prevent early leakage. Initiating CAPD with low dialysate volume has also been recommended as a good practice measure. Although peritonitis and exit-site infections are the most frequent causes of technical failure in peritoneal dialysis (PD), dialysate leaks represent one of the major noninfectious complications of PD. In some instances, dialysate leakage may lead to discontinuation of the technique (1). Despite its importance, the incidence, risk factors, management, and outcome of dialysate leakage are poorly characterized in the literature. We will review the limited available information on this topic in the next few sections.     

Dialysate copeptin and peritoneal transport in incident peritoneal dialysis patients

International Urology and Nephrology - Systemic and intraperitoneal inflammation are characteristic features of patients with end-stage renal disease undergoing chronic peritoneal dialysis (PD)....     

腹膜透析患者透出液糖类抗原125浓度变化的观察

目的分析腹膜透析透出液糖类抗原125(carbohydrate antigen 125,CA125)浓度在长期腹膜透析过程中的变化,探讨CA125在腹膜透析中的临床意义。方法以2013年1月至2014年12月在陕西省人民医院腹膜透析中心随访的终末期肾脏疾病患者32例为研究对象,其中男15例,女17例;年龄29~64岁,平均年龄为(50.1±16.4)岁。随访期内有7例患者发生过1次腹膜透析相关性腹膜炎。观察持续不卧床腹膜透析患者2年中透出液CA125浓度及腹膜功能的变化;观察仅发生1次腹膜透析相关性腹膜炎患者(7例)透出液中CA125在腹膜炎前、腹膜炎时、腹膜炎治愈后(1个月)的浓度变化;采用微量酶免疫法测定CA125浓度,行腹膜平衡试验评估腹膜转运功能。结果腹膜透析透出液中CA125的浓度呈逐渐递减趋势;0个月时为(17.1±3.1)U/rnl,6个月时为(18.4±3.5)U/ml,12个月时为(16.5±2.4)U/ml,18个月时为(15.6±1.9)U/ml,24个月时为(10.3±2.9)U/ml;而代表腹膜功能的平衡试验中4 h腹透液与血清肌酐的比值(4-hour dialysate-to-plasma creatinine,4h D/Pcr)呈逐渐升高趋势:0个月时为0.57±0.02,6个月时为0.60±0.15,12个月时为0.61±0.16,18个月时为0.62±0.13,24个月时为0.65±0.11。在随访过程中,共发生腹膜炎7例;腹膜炎时CA125浓度明显升高[(34.9±5.8)U/ml],与腹膜炎前CA125浓度[(16.5±2.7)U/ml]及腹膜炎治愈后CA125浓度[(17.4±2.1)U/ml]相比,差异均有统计学意义(P均0.05)。结论随着腹膜透析时间的延长,透出液CA125的浓度有所减少,腹膜转运功能逐渐增加;腹膜炎时,透出液CA125呈短期骤升表现,CA125浓度变化与腹膜炎有相关性。     

Serum albumin at 1 year after peritoneal dialysis predicts long-term outcomes on continuous ambulatory peritoneal dialysis

BackgroundHypoalbuminemia at baseline is a powerful predictor of long-term outcomes in peritoneal dialysis patients. However, the levels of serum albumin are dynamically changed during PD. The present study investigated whether the improvement of hypoalbuminemia during PD can affect the patients’ outcomes.Methods436 consecutive incidents continuous ambulatory peritoneal dialysis patients were involved in this study. Demographic, hematologic, biochemical, and dialysis-related data at baseline as well as 1 year after PD were collected. All patients were followed for at least 1 year for mortality.ResultsAmong the 436 patients, the mean age was 48.44 ± 14.98 years, with 58.26% males and 18.12% prevalence of diabetes. The mean follow-up time was 48.25 ± 24.05 months. During the follow-up period, a total of 68 patients died. Serum albumin was 34.35 ± 5.65 g/L at baseline, which increased to 37.39 ± 5.05 g/L at 1 year after PD. Multivariate linear regression analysis showed that sex, age, BMI, diabetic nephropathy, as well as albumin at baseline were independently associated with albumin at 1 year. Every 1 year of age rise would result in a 3.9% increase in the risk of mortality (HR = 1.039, 95%CI 1.016–1.061, p = 0.001). Every 1 g/L increase in albumin at 1 year after PD confers an 8.7% decrease in the risk of mortality (HR = 0.913, 95%CI 0.856–0.973, p = 0.005).ConclusionThe level of serum albumin was increased in the first year of PD. Serum albumin after 1 year of PD predicted mortality in peritoneal dialysis.     

Serum and peritoneal dialysate thyroid hormone levels in patients on continuous ambulatory peritoneal dialysis

Thyroid function tests were performed on 16 clinically euthyroid patients with end-stage renal failure undergoing regular haemodialysis or continuous ambulatory peritoneal dialysis and compared with 8 healthy subjects. The patient groups were carefully matched, especially regarding relative duration of dialysis (mean of 24 months). Total serum thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine and reverse triiodothyronine were significantly lower in both patient groups than control. The thyrothrophin response to the standard thyrotrophin-releasing hormone test was delayed and blunted. Using a novel concentration technique we measured loss of T4 in peritoneal dialysate effluent and found it to be approximately 10% of daily thyroidal T4 release.     

Dialysate leakage into pericardium in an infant on long-term peritoneal dialysis

We report on a 2-year-old boy on automated peritoneal dialysis (PD) with a history of multiple hernias and dialysate leaks who developed pericardial effusion. Magnetic resonance imaging (MRI) demonstrated a peritoneo-pericardial fistula. Dialysis had to be discontinued, since head-down tilt reproducibly induced significant hypotension. In PD patients with pericardial effusion a peritoneo-pericardial leak should be considered.     

Infection-resistant continuous peritoneal dialysis catheters

The techniques of bonding of anionic antibiotics by treatment with cationic surfactants were applied to continuous ambulatory peritoneal dialysis (CAPD) catheters. The elution of 14C-penicillin from tridodecylmethylammonium chloride (TDMAC) treated silicone elastomer catheters in dialysis solution was biphasic, with 95% dissociated from the catheter by 48 h. Forty percent of the TDMAC left the catheter surface during the initial 2 days. The ability of the surfactant TDMAC to bind antibiotics after incubation in dialysis solution correlated directly with the amount of surfactant remaining. Rats with intraperitoneal dialysis catheters were inoculated with exit site and intraluminal bacterial challenges. Intraperitoneal catheter tips treated with TDMAC-penicillin were rendered more resistant to colonization after exit site and intraluminal bacterial challenges.     

Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients

High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.      

Evaluation of continuous ambulatory peritoneal dialysis

This study was undertaken to ascertain whether 19 patients maintained on continuous ambulatory peritoneal dialysis (CAPD) for at least 1 year experienced any deterioration in peritoneal membrane function. Selected serum chemistries and skinfold measurements were also evaluated to determine whether patients dialyzed by CAPD could maintain a normal nutritional status. This study demonstrates that patients maintained on CAPD had stable dialysate protein losses, glucose absorption from the dialysate, and constant urea, creatinine, and sodium removal. When these patients were subdivided by incidence of peritonitis, the group with a lower incidence of peritonitis (one episode every 349 +/- 155 SEM days) showed stable serum protein concentration and improvement in upper arm area whereas the group with a high incidence of peritonitis (one episode every 95 +/- 7 SEM days) showed a reduction in upper arm muscle area. Thus, our data suggest that over a 1-year period, there is no deterioration in peritoneal membrane characteristics and CAPD is effective in maintaining the nutritional status of the patient. However, both membrane function and nutritional status may be impaired by frequent episodes of infection.     

Dialysate bacterial endotoxin as a prognostic indicator of peritoneal dialysis related peritonitis

Peritonitis is the major complication of peritoneal dialysis (PD). The aim of our present study is to explore the prognostic value of endotoxin level in PD effluent for the prediction of treatment failure in PD‐related peritonitis. We studied 325 peritonitis episodes in 223 patients. PD effluent (PDE) was collected every 5 days for endotoxin level and leukocyte count. Patients were followed for relapsing or recurrent peritonitis. We found 20 episodes (6.2%) had primary treatment failure; 41 (12.6%) developed relapsing, 19 (5.8%) had recurrent, and 22 (6.8%) had repeat episodes. Endotoxin was detectable in the PDE of 19 episodes (24.4%) caused by Gram negative organisms, 4 episodes (6.8%) of mixed bacterial growth, and none of the culture negative episodes or those by Gram positive organisms. For episodes caused by Gram negative bacteria, a detectable endotoxin level in PDE on day 5 had a sensitivity and specificity of 66.7% and 83.3%, respectively, for predicting primary treatment failure. In contrast, PDE leukocyte count > 1000 per mm3 on day 5 had a sensitivity and specificity of 88.9% and 89.1%, respectively; the addition of PDE endotoxin assay did not improve the sensitivity or specificity. We conclude that detectable endotoxin in PDE 5 days after antibiotic therapy might predict primary treatment failure in peritonitis episodes caused by Gram negative organisms. However, the sensitivity and specificity of PDE endotoxin assay was inferior to PDE leukocyte count.     

Hypophosphatemia in infants on continuous ambulatory peritoneal dialysis

Three infants with irreversible renal failure and treated with continuous ambulatory peritoneal dialysis (CAPD) developed hypophosphatemia. In one of them rachitic lesions were observed on X-ray and bone biopsy showed osteomalacic osteodystrophy. Different mechanisms may have been at the origin of the hypophosphatemia: high doses of phosphate binders, low phosphorus intake, phosphate loss with the dialysate and possibly nutritional repletion. Dietary phosphorus restriction and use of phosphate binders should be applied with caution and serum phosphate should be monitored regularly in infants treated with CAPD.     

Effluent CA 125 concentration in chronic peritoneal dialysis patients: influence of PD duration,peritoneal transport and PD regimen

In terms of the integrity of the peritoneal membrane in peritoneal dialysis (PD), the peritoneal mesothelial cells play a pivotal role since its monolayer constitutes the first line of the peritoneal membrane. Cancer antigen 125 (CA 125) is released by peritoneal mesothelial cells and correlates with the mesothelial cell mass in PD. Since its effluent concentration is easy to determine in chronic PD patients, CA 125 serves as an in vivo marker of biocompatibility. We performed a cross-sectional study to investigate the relation between PD duration, peritoneal transport and the PD regimen (CAPD/CCPD) on effluent CA 125 concentration in 22 chronic PD patients. We compared long-term (>6 months) with short-term PD treatment, patients with high small solute transport properties (MTAC >11 ml/min, d/p ratio of creatinine >0.72) to patients with low small solute transport and CAPD with APD patients. A peritoneal equilibration test was performed with 1.36% glucose. Dialysate/plasma (D/P) ratio and mass transfer area coefficient (MTAC) of creatinine were calculated and the 4-hour effluent concentration of CA 125 was determined. CA 125 tended to be lower in the long-term PD patients and also in APD patients, but statistical significance was missing. Effluent CA 125 was significantly increased in patients with an MTAC of creatinine >11 ml/min (40.2 +/- 11.2 vs. 20.7 +/- 1.2 U/ml) and in patients with a d/p ratio of creatinine >0.72 (48.2 +/- 11.0 vs. 21.6 +/- 1.6 U/ml). CA 125 and the d/p ratio of creatinine were positively correlated (r = 0.68). The positive correlation of CA 125 with peritoneal small solute transport especially in the early phase of PD treatment indicates an initial correlation of the mesothelial cell mass with the peritoneal surface area. A direct relation between the CA 125 concentration and peritoneal transport is unlikely. In our study the CA 125 effluent concentration tended to be lower in long-term PD patients and also in APD patients, possibly indicating a cell depletory influence of the conventional PD fluid.