Benefits of peritoneal ultrafiltration in HFpEF and HFrEF patients.

BACKGROUND: Peritoneal ultrafiltration (pUF) in refractory heart failure (HF) reduces the incidence of decompensation episodes, which is of particular significance as each episode incrementally adds to mortality. Nevertheless, there are insufficient data about which patient cohort benefits the most. The objective of this study was to compare pUF in HFrEF and HFpEF, focusing on functional status, hospitalizations, surrogate endpoints and mortality. METHODS: This study involves 143 patients, who could be classified as either HFpEF (n = 37, 25.9%) or HFrEF (n = 106, 74.1%) and who received pUF due to refractory HF. RESULTS: Baseline eGFR was similar in HFrEF (23.1 ± 10.6 mg/dl) and HFpEF (27.8 ± 13.2 mg/dl). Significant improvements in NYHA class were found in HFpEF (3.19 ± 0.61 to 2.72 ± 0.58, P <  0.001) and HFrEF (3.45 ± 0.52 to 2.71 ± 0.72, P <  0.001). CRP decreased in HFrEF (19.4 ± 17.6 mg/l to 13.7 ± 21.4 mg/l, P = 0.018) and HFpEF (33.7 ± 52.6 mg/l to 17.1 ± 26.3 mg/l, P = 0.004). Body weight was significantly reduced in HFrEF (81.1 ± 14.6 kg to 77.2 ± 15.6 kg, P = 0.003) and HFpEF (86.9 ± 15.8 kg to 83.1 ± 15.9 kg, P = 0.005). LVEF improved only in HFrEF (25.9 ± 6.82% to 30.4 ± 12.2%, P = 0.046). BCR decreased significantly in HFrEF and HFpEF (55.7 ± 21.9 to 34.3 ± 17.9 P > 0.001 and 50.5 ± 68.9 to 37.6 ± 21.9, P = 0.006). Number of hospitalization episodes as well as number of hospitalization days decreased significantly only in HFpEF (total number 2.88 ± 1.62 to 1.25 ± 1.45, P <  0.001, days 40.4 ± 31.7 to 18.3 ± 22.5 days, P = 0.005). CONCLUSIONS: pUF offers various benefits in HFpEF and HFrEF, but there are also substantial differences. In particular, hospitalization rates were found to be significantly reduced in HFpEF patients, indicating a greater medical and economical advantage. However, LVEF was only found to be improved in HFrEF patients. While pUF can now be regarded as an option to supplement classical HF therapy, further studies are desirable to obtain specifications about pUF in HFpEF, HFmEF and HFrEF patients.

Recirculating peritoneal dialysis system using urease-fixed silk fibroin membrane filter with spherical carbonaceous adsorbent.

The chronic kidney disease (CKD) patients are undergoing continuous ambulatory peritoneal dialysis (CAPD). However, there are some constraints, the frequent exchange of the dialysate and limitation of outside activity, associated with CAPD remain to be solved. In this study, we designed the wearable artificial kidney (WAK) system for peritoneal dialysis (PD) using urease-immobilized silk fibroin (SF) membrane and polymer-based spherical carbonaceous adsorbent (PSCA). We evaluated this kit's removal abilities of uremic toxins such as urea, creatinine, uric acid, phosphorus, and ß2-microglobulin from the dialysate of end-stage renal disease (ESRD) patients in vitro. The uremic toxins including urea, creatinine, uric acid, and phosphorus were removed about 99% by immobilized SF membrane and PSCA filter after 24 h treatment. However, only 50% of ß2-microglobulin was removed by this filtering system after 24 h treatment. In vivo study result shows that our filtering system has more uremic toxins removal efficiency than exchanged dialysate at every 6 h. We suggest that recirculating PD system using urease-immobilized SF membrane with PSCA could be more efficient than traditional dialysate exchange system for a WAK for PD.

Monitored anesthesia care based on ultrasound-guided subcostal transversus abdominis plane block for continuous ambulatory peritoneal dialysis catheter surgery: case series.

Planning safe perioperative management for patients undergoing continuous ambulatory peritoneal dialysis (CAPD) catheter surgery (insertion and extraction of the catheter) is often difficult because many of these patients not only have renal insufficiency but also have co-existing disorders, such as heart diseases. As increased indications for perioperative anticoagulation therapy have limited the choice of anesthesia, selecting an appropriate anesthetic method, particularly for patients with poor systemic conditions, is becoming more challenging. We report seven cases of CAPD catheter surgery successfully managed by monitored anesthesia care using subcostal transversus abdominis plane (TAP) block with additional local anesthetic infiltration and analgesics. Despite co-existing cardiac disease and/or coagulation disorders, all patients were safely managed without any other major anesthetic methods. Subcostal TAP block is a useful anesthetic option for CAPD catheter surgery, particularly for patients with poor systemic conditions and/or in whom neuraxial blocks are contraindicated.

Randomized, double-blind, placebo-controlled trial of spironolactone for hypokalemia in continuous ambulatory peritoneal dialysis patients.

The incidence of hypokalemia in continuous ambulatory peritoneal dialysis (CAPD) patients is about 15-60%, leading to significant complications. There is no standard treatment other than potassium supplement in this setting. The aim of this study was to evaluate effect of spironolactone 25 mg/day in CAPD patients who have a history of hypokalemia. This is a randomized, double-blind, placebo-controlled, cross-over study in CAPD patients who had a history of hypokalemia. Study intervention is 4 weeks of oral spironolactone 25 mg/day or placebo, cross-over after a 2-week wash-out period. The primary outcome was the difference of serum potassium before and after 4 weeks of spironolactone treatment. Serum potassium was measured every 2 weeks, serum magnesium, urine and peritoneal fluid potassium measured before and after each treatment period. We enrolled 24 patients, and 20 completed the cross-over study. Ten patients were anuric. The total doses of potassium supplement were the same during the study period. Serum potassium levels before and after study intervention were not significantly different in both groups (4.23 ± 0.64 vs. 3.90 ± 0.59 mEq/L for spironolactone P = 0.077 and 3.84 ± 0.62 vs. 3.91 ± 0.52 for placebo P = 0.551). Total 24-h potassium, magnesium, sodium excretion, urine volume and ultrafiltration volume were not affected by spironolactone or placebo. There was one episode of hyperkalemia (5.6 mEq/L) during the spironolactone treatment period. Spironolactone 25 mg/day does not have a significant effect on serum potassium or urine and peritoneal excretion rate in CAPD patients who have a history of hypokalemia.

The role of an integrated care model for kidney disease in the development of peritoneal dialysis: a single-center experience in China.

Peritoneal dialysis plays a crucial role in the integrated care of patients with end-stage renal disease (ESRD). In this paper, we retrospectively analyzed the quality indicators of peritoneal dialysis (PD) in 712 patients from our center who underwent PD between 2004 and 2011. In 43% of patients, follow-up was undertaken every 3 months at our outpatient department, and 54% patients were followed up by both our hospital and other local hospitals. The patient survival rate at 1, 3 and 5 years was 96.3%, 85.4% and 76.2%, respectively. The technique survival (excludes death/transplantation) at 1, 3 and 5 years was 95.1%, 87.7% and 79.6%, respectively. Fluid overload occurred in 29.2% of patients and was one of the major reasons for discontinuing PD. The peritonitis rate in our center decreased to 0.16 episodes/year in 2011. In addition, since our center is one of the largest integrated-treatment centers for ESRD in China, we have developed a multilevel care program in Zhejiang Province, which resulted in rapid growth of PD in our province in recent years.

Organic nitrates favor regression of left ventricular hypertrophy in hypertensive patients on chronic peritoneal dialysis.

The aim of the study was to evaluate the effect of nitrates on left ventricular hypertrophy (LVH) in hypertensive patients on chronic peritoneal dialysis (PD). Sixty-four PD patients with hypertension were enrolled in this study. All patients accepted antihypertensive drugs at baseline. Thirty-two patients (nitrate group) took isosorbide mononitrate for 24 weeks. The remaining 32 patients (non-nitrate group) took other antihypertensive drugs. Blood pressure (BP), left ventricular mass index (LVMI) and plasma asymmetric dimethylarginine (ADMA) were monitored. Subjects with normal renal function were included as the control group (n = 30). At baseline, plasma ADMA levels in PD patients were significantly higher than the control group, but there was no significant difference in plasma ADMA levels between the two groups. At the end of the 24-week period, BP, LVMI, LVH prevalence and plasma ADMA levels in the nitrate group were significantly lower than those in the non-nitrate group. BP did not show a significant difference between 12 and 24 weeks in the nitrate group with a reduced need for other medication. Logistic regression analysis showed that nitrate supplementation and SBP reduction were independent risk factors of LVMI change in PD patients after adjusting for age, gender, diabetes history and CCB supplementation. It was concluded that organic nitrates favor regression of LVH in hypertensive patients on chronic peritoneal dialysis, and nitrates may be considered for use before employing the five other antihypertensive agents other than nitrates.

Oxidative stress in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and the significant role of vitamin C and E supplementation.

PURPOSE: Chronic renal failure patients undergoing peritoneal dialysis (PD) are characterized by increased oxidative stress (OS), which is associated with enhanced cardiovascular risk. Moreover, oxidative stress also contributes to peritoneal membrane changes and ultrafiltration failure. The aim of this study was to evaluate OS in PD patients and the effect of treatment with ascorbic acid and α-tocopherol. METHODS: Plasma, erythrocyte, urine, and peritoneal effluent samples from 20 patients on PD were evaluated for glutathione peroxidase and superoxide dismutase activity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels, as well as protein carbonyl formation, before and after administration of vitamin C, alone or in combination with vitamin E, in comparison with 10 apparently healthy control individuals. RESULTS: All studied markers showed enhanced OS in the PD group, compared to controls. The supplementation of vitamin C and E resulted in improvements of all the OS markers, as indicated by increased erythrocyte antioxidant enzymes activity and TAC levels, as well as decreased MDA concentration and carbonyl compound formation. CONCLUSIONS: The oral supplementation of antioxidant vitamins C and E, in combination, can lead to decreased OS, thus providing a useful and cost-effective therapeutic option in PD patients.

Quantification of peritoneal transport.

Kinetic models have been used in both hemodialysis (HD) and peritoneal dialysis (PD) therapies. Because many different theoretical models are available, users should choose a model that suits the purpose of their studies. In general, simple models are useful for clinical investigations and research; rigorous models may be available with the use of computers. Several commercial software packages with rigorous models specifically designed for PD are also useful for analyzing patient data and for constructing prescriptions. Although the overall mass transfer area coefficient (MTAC) is a parameter for diffusion transport, it may become a useful tool for predicting peritoneal ultrafiltration by defining a new "index for peritoneal diffusive selectivity" (IPDS), the ratio of the MTACs for urea and creatinine. Kinetic models are especially useful in treatments with relatively complex prescriptions such as combined PD and HD ("complementary") therapy, sample calculations of which are discussed.

Dialysis outcomes in Colombia (DOC) study: a comparison of patient survival on peritoneal dialysis vs hemodialysis in Colombia.

The goal of the Dialysis Outcomes in Colombia (DOC) study was to compare the survival of patients on hemodialysis (HD) vs peritoneal dialysis (PD) in a network of renal units in Colombia. The DOC study examined a historical cohort of incident patients starting dialysis therapy between 1 January 2001 and 1 December 2003 and followed until 1 December 2005, measuring demographic, socioeconomic, and clinical variables. Only patients older than 18 years were included. As-treated and intention-to-treat statistical analyses were performed using the Kaplan-Meier method and Cox proportional hazard model. There were 1094 eligible patients in total and 923 were actually enrolled: 47.3% started HD therapy and 52.7% started PD therapy. Of the patients studied, 751 (81.3%) remained in their initial therapy until the end of the follow-up period, death, or censorship. Age, sex, weight, height, body mass index, creatinine, calcium, and Subjective Global Assessment (SGA) variables did not show statistically significant differences between the two treatment groups. Diabetes, socioeconomic level, educational level, phosphorus, Charlson Co-morbidity Index, and cardiovascular history did show a difference, and were less favorable for patients on PD. Residual renal function was greater for PD patients. Also, there were differences in the median survival time between groups: 27.2 months for PD vs 23.1 months for HD (P=0.001) by the intention-to-treat approach; and 24.5 months for PD vs 16.7 months for HD (P<0.001) by the as-treated approach. When performing univariate Cox analyses using the intention-to-treat approach, associations were with age > or =65 years (hazard ratio (HR)=2.21; confidence interval (CI) 95% (1.77-2.755); P<0.001); history of cardiovascular disease (HR=1.96; CI 95% (1.58-2.90); P<0.001); diabetes (HR=2.34; CI 95% (1.88-2.90); P<0.001); and SGA (mild or moderate-severe malnutrition) (HR=1.47; CI 95% (1.17-1.79); P=0.001); but no association was found with gender (HR=1.03, CI 95% 0.83-1.27; P=0.786). Similar results were found with the as-treated approach, with additional associations found with Charlson Index (0-2) (HR=0.29; Cl 95% (0.22-0.38); P<0.001); Charlson Index (3-4) (HR=0.61; Cl 95% (0.48-0.79); P<0.001); and SGA (mild-severe malnutrition) (HR=1.43; Cl 95% (1.15-1.77); P<0.001). Similarly, the multivariate Cox model was run with the variables that had shown association in previous analyses, and it was found that the variables explaining the survival of patients with end-stage renal disease in our study were age, SGA, Charlson Comorbidity Index 5 and above, diabetes, healthcare regimes I and II, and socioeconomic level 2. The results of Cox proportional risk model in both the as-treated and intention-to-treat analyses showed that there were no statistically significant differences in survival of PD and HD patients: intention-to-treat HD/PD (HR 1.127; CI 95%: 0.855-1.484) and as-treated HD/PD (HR 1.231; CI 95%: 0.976-1.553). In this historical cohort of incident patients, there was a trend, although not statistically significant, for a higher (12.7%) adjusted mortality risk associated with HD when compared to PD, even though the PD patients were poorer, were more likely to be diabetic, and had higher co-morbidity scores than the HD patients. The variables that most influenced survival were age, diabetes, comorbidity, healthcare regime, socioeconomic level, nutrition, and education.

Automated vs continuous ambulatory peritoneal dialysis: a systematic review of randomized controlled trials.

BACKGROUND: A systematic review of randomized controlled trials (RCTs) comparing continuous ambulatory peritoneal dialysis (CAPD) with all forms of automated peritoneal dialysis (APD) was performed to assess their comparative clinical effectiveness. METHODS: The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and CINAHL, were searched for relevant RCTs. Analysis was by a random effects model and results expressed as relative risk (RR) and weighted mean difference (WMD) with 95% confidence intervals (CI). RESULTS: Three trials (139 patients) were identified. APD when compared to CAPD was found to have significantly lower peritonitis rates (two trials, 107 patients, rate ratio 0.54, 95% CI 0.35-0.83) and hospitalization rates (one trial, 82 patients, rate ratio 0.60, 95% CI 0.39-0.93) but not exit-site infection rates (two trials, 107 patients, rate ratio 1.00, 95% CI 0.56-1.76). However no differences were detected between APD and CAPD in respect to risk of mortality (RR 1.49, 95% CI 0.51-4.37), peritonitis (RR 0.75, 95% CI 0.50-1.11), switching from the original peritoneal dialysis (PD) modality to a different dialysis modality including an alternative form of PD (RR 0.50, 95% CI 0.25-1.02), PD catheter removal (RR 0.64, 95% CI 0.27-1.48) and hospital admissions (RR 0.96, 95% CI 0.43-2.17). Patients on APD were found to have significantly more time for work, family and social activities. CONCLUSIONS: APD appears to be more beneficial than CAPD, in terms of reducing peritonitis rates and with respect to certain social issues that impact on patients' quality of life. Further, adequately powered trials are required to confirm the benefits for APD found in this review and detect differences with respect to other clinically important outcomes that may have been missed by the trials included in this review due to their small size and short follow-up periods.

DNA oxidative damage in patients with dialysis treatment.

BACKGROUND/AIMS: Chronic renal patients on hemodialysis (HD) and peritoneal dialysis (PD) treatment are exposed to oxidative stress and DNA damage. The objective of this study was to assess the oxidative damage to DNA in end-stage chronic renal failure, before and after vitamin E supplementation. METHODS: Patients on HD (n=29) and PD (n=22) received oral supplementation with 300 mg vitamin E three times a week for 4 weeks. A blood sample was collected at the beginning and at the end of the supplementation cycle for the determination of vitamin E levels (high-performance liquid chromatography), carbonyl groups, and DNA damage (8-hydroxy 2'-deoxyguanosine [8-OHdG] and comet assay). RESULTS: After supplementation, vitamin E concentration was increased by about 50%. Protein oxidation was initially observed in both groups, with a reduction after supplementation. DNA damage detected by the comet assay and by 8-OHdG analysis was significantly reduced (p<0.05) after supplementation in both groups. CONCLUSIONS: Vitamin E supplementation reduced oxidative DNA damage in both HD and PD patients. Treatments such as HD and PD induce oxidative stress and consequent DNA damage, and increased plasma vitamin E levels significantly contribute to the normalization of these events.

The relation between hypoalbuminemia and compliance and intima-media thickness of carotid artery in continuous ambulatory peritoneal dialysis patients.

The aim of this study was to identify the main factor affecting compliance and intima-media thickness of the elastic common carotid artery in continuous ambulatory peritoneal dialysis patients. Increased intima-media thickness and decreased arterial compliance are associated with elevated risk of cardiovascular disease. This study included 20 patients and 20 age- and sex- matched healthy control subjects. The compliance and intima-media thickness of the right common carotid artery within 1 cm to the bifurcation were measured three times using high-resolution B-mode echocardiography. Blood samples were obtained to measure levels of hemoglobin, phosphorus, total calcium, total CO2, serum albumin, C-reactive protein, serum total cholesterol, LDL- and HDL-cholesterol and triglycerides. We found that the compliance of common carotid artery was lower in the patient group than in the control group. In the patient group, the compliance of common carotid artery was positively correlated with serum albumin concentration, and intima-media thickness of common carotid artery was negatively correlated with serum albumin levels. Stepwise regression analysis showed that serum albumin concentration was independently related to the compliance of common carotid artery, suggesting hypoalbuminemia can independently give deleterious effects on the arterial wall in continuous ambulatory peritoneal dialysis patients.

The impact of various cycling regimens on phosphorus removal in chronic peritoneal dialysis patients.

BACKGROUND: The National Kidney Foundation Dialysis Outcome Quality Initiative clinical practice guidelines have suggested that serum phosphate levels be maintained at < or =5.5 mg/dL in patients maintained on dialysis. Over 45% of anuric patients maintained on CAPD have serum phosphate levels >5.5 mg/dL. The present study was designed to address the question whether phosphate removal could be enhanced by increasing the dialysate volume during cycler peritoneal dialysis therapy. METHODS: Medically stable patients maintained on chronic peritoneal dialysis therapy, who were high or high-average transporters and had serum phosphate levels > or =5.5 mg/dL, were invited to participate in the study. The protocol involved measuring phosphate and creatinine clearances at weekly intervals on three different cycler prescriptions consisting of 7 and 12 full cycles or 24 cycles with 50% tidal PD (TPD) over 9 hours. Ten patients agreed to participate. Those patients (n=7) with a BMI > 22 had 2 liter (L) fill volumes and 14 L of total dialysate (7 cycles of 2 L) or 24 L total dialysate (12 cycles of 2 L or 50% TPD with 24 cycles).The patients (n=3) with a BMI < 20 had 1.2 L fill volumes and 8.4 L total dialysate (7 cycles) or 14.4 L total dialysate (12 cycles of 1.2 L or 50% TPD with 24 cycles). RESULTS: The mean age (+/- SD) of the study patients was 50.8 (+/- 9.3) years. There were 6 females, 6 Caucasians and 4 African-Americans. The mean weight of the patients was 71.5 (+/- 24.2) kg and mean height 1.65 (+ 7.6) meters. The mean BMI was 18.3 (+/- 1.27) in the < 20 BMI group and 30.3 (+/- 6.6) in the > 22 BMI group. The mean phosphate clearance (L/night/1.73m 2 ) increased from 3.96 (+/- 1.16) with 7 cycles to 4.71 (+ 1.81) with 12 cycles and 4.51 (+/- 1.61) with 50% TPD. Creatinine clearance (L/night/1.73m 2 ) was 4.74 (+/- 1.74) with 7 cycles, 6.06 (+/- 2.04) with 12 cycles and 5.61 (+/- 2.01) with TPD. CONCLUSION: The present study indicates that there is a significant, 19% (P < 0.005) rise in phosphate clearance by increasing dialysate volume 71% from 7 cycles to 14 cycles compared to a 27% increase in creatinine clearance. With tidal PD, phosphate clearance increased by 12% (p=NS) and creatinine clearance increased 18 % (p, 0.02). This increase in phosphate clearance translates into <50 mg net phosphate removal in 9 hours, assuming a serum phosphate of 6 mg/%. Thus, increasing dialysis cycles and volume results in only a minimal increase in net phosphate removal.

The Relation Between Hypoalbuminemia and Compliance and Intima-media Thickness of Carotid Artery in Continuous Ambulatory Peritoneal Dialysis Patients

The aim of this study was to identify the main factor affecting compliance and intima-media thickness of the elastic common carotid artery in continuous ambulatory peritoneal dialysis patients. Increased intima-media thickness and decreased arterial compliance are associated with elevated risk of cardiovascular disease. This study included 20 patients and 20 age- and sex- matched healthy control subjects. The compliance and intima-media thickness of the right common carotid artery within 1 cm to the bifurcation were measured three times using high-resolution B-mode echocardiography. Blood samples were obtained to measure levels of hemoglobin, phosphorus, total calcium, total CO2, serum albumin, C-reactive protein, serum total cholesterol, LDL- and HDL-cholesterol and triglycerides. We found that the compliance of common carotid artery was lower in the patient group than in the control group. In the patient group, the compliance of common carotid artery was positively correlated with serum albumin concentration, and intima-media thickness of common carotid artery was negatively correlated with serum albumin levels. Stepwise regression analysis showed that serum albumin concentration was independently related to the compliance of common carotid artery, suggesting hypoalbuminemia can independently give deleterious effects on the arterial wall in continuous ambulatory peritoneal dialysis patients.

Intravenous treatment of hyperhomocysteinemia in patients on chronic hemodialysis--a pilot study.

BACKGROUND: Treatment of hyperhomocysteinemia in patients with end-stage renal disease (ESRD) can be performed with the oral application of vitamins. However, this therapy rarely normalizes total homocysteine (tHcy) levels. Frequently, a rebound is observed after the end of treatment. Currently, no data are available about intravenous combination therapy with folic acid, pyridoxine (B6), and cyanocobalamin (B12). METHODS: We conducted a prospective pilot study comprising 13 patients on chronic hemodialysis treatment (63.7+/-4.9 years; 6 female, 7 male) for 27 weeks. The patients received 10 mg folic acid and 100 mg pyridoxine intravenously (IV) after each dialysis plus 1000 microg vitamin B12 IV once a week for 9 weeks. Between weeks 10 and 18 the patients received 10 mg folic acid, 100 mg vitamin B6 once a week, and 1000 microg vitamin B12 bimonthly IV. RESULTS: The therapy regimen decreased tHcy concentration (baseline: 30.5+/-2.2 micromol/L) significantly to 17.4+/-1.2 micromol/L, 15.6+/-1.0 micromol/L, and 16.4+/-0.1 micromol/L after 3, 6, and 9 weeks, respectively (p<0.01 vs. baseline concentration). The maximum reduction (-47.5+/-3.3%) of tHcy concentration was measured after 6 weeks of therapy. During the following maintenance therapy, tHcy-levels did not increase and no rebound of tHcy was detected during follow-up (week 27:16.5+/-1.97 micromol/L). CONCLUSION: The concept of a short, high-dose induction therapy with intravenous folic acid, pyridoxine, cyanocobalamin, and a subsequent low-dose maintenance regimen is effective in the treatment of hyperhomocysteinemia in patients with ESRD.

[Changes in selected parameters of bone turnover resulting from use of different calcium concentrations in dialysate of patients treated with CAPD]. / Zmiennosc wybranych parametrów przemiany kostnej przy zastosowaniu dwóch róznych stezen wapnia w plynie dializacyjnym u pacjentów dializowanych otrzewnowo.

Renal osteodystrophy is a common complication occurring in patients with end stage disease. Using dialysis solutions with different concentrations of calcium undoubtedly has an influence on calcium-phosphorus homeostasis and bone turnover. The aim of the study was to examine the influence of dialysate with calcium concentrations of Ca 1.75 mmol/l and Ca 1.25 mmol/l on selected parameters of bone turnover. The study was performed on 12 clinically stable patients treated with CAPD. After 24 weeks of the treatment with Ca 1.75 mmol/l solution the initial investigation was performed. The next step was to switch to dialysate with the Ca level of 1.25 mmol/V. After 2, 12, and 24 weeks of the treatment with solutions of low calcium level the concentrations of PTH, osteocalcin, total calcium, and ionized calcium, phosphorus were calculated. We have observed that the level of PTH and osteocalcin was increased significantly at the time of treatment with Ca 1.25 mmol/l solution. We have also observed a decrease in concentration of total and ionized calcium. We did not observe any change of phosphorus concentrations in the serum of treated patients.

Calcium balance during pulse alfacalcidol therapy for secondary hyperparathyroidism in CAPD patients treated with 1.0 and 1.25 mmol/L dialysate calcium.

Hypercalcemia frequently occurs in continuous ambulatory peritoneal dialysis (CAPD) patients treated with calcium carbonate and vitamin D metabolites. To reduce the incidence of this complication, it has been proposed to use dialysate solutions with a low calcium concentration. However, there is concern that these solutions may lead to a negative calcium balance. We measured calcium balance in 13 CAPD patients with secondary hyperparathyroidism who were treated with calcium carbonate and alfacalcidol, 2 microg twice weekly, while using 1.0- (1.0 group) and 1.25-mmol/L (1.25 group) dialysate calcium solutions. Calcium absorption was measured after the administration of Ca47. Results for the 1.0 (n = 6) and 1.25 (n = 7) groups included fractional calcium absorptions of 0.14 (range, 0.09 to 0.27) and 0.08 (range, 0.03 to 0.40; P = not significant [NS]) and calcium absorptions of 380 +/- 92 and 331 +/- 83 mg/d (P = NS). Dialysate calcium losses were 93 +/- 20 and 91 +/- 26 mg/d, and total calcium losses (dialysate and urine) were 106 +/- 16 and 108 +/- 40 mg/d (P = NS). Calcium balance was positive in all patients (274 +/- 92 and 223 +/- 65 mg/d; P = NS). These data suggest that the use of 1.0- and 1.25-mmol/L calcium solutions in conjunction with calcium carbonate and pulse alfacalcidol therapy is associated with a positive calcium balance in CAPD patients.