Iron absorption in erythropoietin-treated haemodialysis patients; effects of iron availability, inflammation and aluminium

Background: The response to recombinant human erythropoietin (rHuEpo) is determined primarily by the availability of iron. In contrast to i.v. iron, oral iron supplementation is often insufficient for an optimal response. Method: We studied iron absorption and the effects of iron status, aluminium status and inflammation in 19 chronic haemodialysis patients on maintenance rHuEpo therapy. Iron mucosal uptake after 24 h, iron retention after 2 weeks and mucosal transfer of iron were determined with a whole-body counter using an oral dose ⁵⁹Fe. Iron absorption was measured once without, and once after the ingestion of 2 g aluminium hydroxide. Results: On the basis of transferring saturation, two groups of dialysis patients were distinguished: a group with a functional iron deficiency (n=9), and an iron-deficient dialysis patients group, mucosal uptake, mucosal transfer, and iron retention were 49.9%±29.4, 0.73±0.29, and 41.6%±32.2, being significantly lower than in a non-uraemic iron deficient population (P <0.01, P <0.05, P <0.01 respectively). In the iron-replete dialysis patients group, mucosal uptake, mucosal transfer, and iron retention were 20.0±12.3, 0.59±0.18, and 11.1±6.7, mucosal uptake and iron retention being lower than in a normal iron-replete population (P <0.0005 and P <0.003 respectively). Dialysis patients with high C-reactive protein (CRP) values showed lower iron absorption. Iron absorption data correlated significantly with transferrin saturation and CRP in the iron-deficient group, and with serum ferritin in the iron-replete group. Iron absorption decreased after an aluminium hydroxide challenge in the iron-deficient patients to the lower levels of the iron-replete subjects. Body aluminium stores, estimated by the desferrioxamine test, did not correlate with parameters of iron absorption. Conclusion: The absorption of iron in dialysis patients is decreased in haemodialysis patients, which may, at least in part, be due to inflammation. Aluminium ingestion further reduces absorption in functional iron-deficient patients. Key words: anaemia; erythropoietin; iron absorption; haemodialysis      

Serum VCAM-1, ICAM-1, and L-selectin levels in children and young adults with chronic renal failure

Children and young adults with chronic renal failure (CRF) present with an impaired immune response. Our aim was to analyze whether leukocyte migration, determined by adhesion molecules, is disturbed in the course of CRF, hemodialysis (HD), and peritoneal dialysis (PD). Soluble (s) VCAM-1, ICAM-1, and L-selectin serum levels were evaluated by ELISA in 15 patients with CRF, 22 patients on cuprophane membrane HD, 24 patients on PD, and in 15 controls. The sVCAM-1 levels in all groups were significantly elevated compared with controls. The levels in HD patients were higher than in CRF patients (P <0.05), while levels in PD patients were higher than in CRF and HD (P <0.001 and P <0.01, respectively). The sICAM-1 concentrations in CRF and PD patients were significantly elevated compared with controls (P <0.001 and P <0.0001, respectively); in PD patients sICAM-1 levels were higher than in HD patients (P <0.001), but there were no differences between other groups. sL-selectin levels were decreased in all groups compared with controls. The levels in HD patients were the lowest and the differences, compared with CRF and PD patients, were significant (P <0.05 and P <0.01, respectively). Children and young adults with CRF and on maintenance dialysis have altered concentrations of soluble adhesion molecules, resulting from either inadequate clearance or disturbed synthesis and release. The differences in sVCAM-1 levels between CRF and both groups of patients on dialysis, as well as the differences in sL-selectin concentrations between HD and CRF patients, indicate that these disturbances are aggravated by maintenance dialysis, particularly HD.     

Posttransplant outcomes of peritoneal dialysis versus hemodialysis patients

The impact of dialysis modality on posttransplant outcomes remains controversial. The authors have compared primary failure, delayed graft function (DGF), acute rejection episodes as well as patient and allograft survivals among patients undergoing renal transplantation between 2004 and 2009, according to the modality of hemodialysis (HD) versus peritoneal dialysis (PD). We studied 306 patients (268 HD and 38 PD) with a mean follow-up of 29 ± 16 months. The PD cohort included a predominance of females (68.4% vs 36.2%; P = .001), lower age at transplantation (38 ± 14 vs 46 ± 12 years; P = .004), shorter time on dialysis (33 ± 49 vs 59 ± 157 months; P = .043), and higher rate of living donor grafts (PD 31.6% vs HD 13.1%; P = .003). Donor age (PD 43 ± 13 vs HD 45 ± 14 years; P = .30), human leukocyte antigen mismatch (P = .17), panel reactive antibody values (HD 11 ± 22 vs PD 13 ± 26; P = .55), and hyperimunized patients (HD 3.73%; PD 7.89%; P = .23) were not different. Primary graft failure (3.4% vs 0%; P = .025) and DGF (37.1% vs 13.1%; P = .037) were more frequent among HD patients, but incidences of acute rejection episodes were similar (HD 10.5% vs PD 5.3%; P = 0.19). Neither recipient survival at 1 (97% in PD and HD) or 3 years (HD 90% vs PD 94%; P = .657) nor allograft survival at 1 year (HD 94% vs PD 95%; P = .80) or 3 years: (HD 70%, vs PD 81%; P = .73) were different. Graft function was similar at 1 (HD 64.2 ± 25 vs PD 56.4 ± 24 mL/min; P = .17) and 3 years (HD 62.3 ± 21 vs PD 46 ± 23 mL/min; P = .16). In our study, HD patients showed an higher incidence of DGF and primary allograft failure, but there was no difference in acute rejection episodes, long-term survivals, or renal function.     

Lipid Abnormalities and Oxidized LDL in Chronic Kidney Disease Patients on Hemodialysis and Peritoneal Dialysis

Dyslipoproteinemia and oxidative modification of low-density lipoprotein (oxLDL) contribute to the development of oxidative stress and atherosclerosis in chronic kidney disease (CKD). On the contrary, high-density lipoprotein cholesterol (HDL-C), especially HDL3-C subtype, has protective effect against oxidative damage. There is limited evidence referring HDL-C subclass levels in patients on dialysis. This study was designed to compare lipid abnormalities and oxLDL levels in hemodialysis (HD) and peritoneal dialysis (PD) patients. Serum lipids, HDL subclasses, and oxLDL were measured in 55 patients with CKD-stage 5 (31 patients on HD and 24 patients on PD) and in 21 normal controls (NC). The results showed that in dialysis patients, triglycerides were higher than in controls (p < 0.0001) and HDL-C was significantly lower (p < 0.0001). The HDL2-C subclass concentration did not differ significantly between patients and controls, while HDL3-C was lower in patients (11 ± 0.5 mg/dL) than in NC (23 ± 1, p < 0.0001). oxLDL levels were markedly increased in patients (1.92 ± 0.29 mg/L) compared to NC (0.22 ± 0.05, p < 0.0001). Patients on PD had higher levels of cholesterol (p < 0.001) and apolipoprotein B (p < 0.05) than patients on HD. However, HDL-C, HDL-C subclasses, and oxLDL concentrations did not differ significantly between PD and HD patients. It is concluded that patients with CKD have a nearly 10-fold elevation of oxLDL compared with NC. Patients on PD have differences in the lipid profile compared with patients on HD; however, both modalities seem to possess similar potential to atherosclerosis development.     

Percentage hypochromic red cells and the response to intravenous iron therapy in anaemic haemodialysis

Introduction: Iron deficiency is commonly encountered in haemodialysis (HD) patients and may be overcome by i.v. therapy. We have examined the percentage hypochromic red cells (%HRC) for predicting response to i.v. iron in subjects with a low serum ferritin. Methods: Prospective study of i.v. iron saccharate (trivalent iron 200 mg/week for 8 weeks) in anaemic (Hb <10 g/dl) HD patients with serum ferritin <100 &mgr;g/l despite oral iron therapy. Response to i.v. iron was assessed by comparing Hb at 0 and 8 weeks according to %HRC at baseline (0-3%, 4-9%, ⩾10%). Results are mean±1 SD. Results: For all subjects (n=82), Hb and ferritin increased between 0 and 8 weeks (8.9±1.0 to 10.1±1.4, P<0.0001; 55±24 to 288±126, P<0.0001). Patients were stratified into three groups according to %HRC at baseline (0-3%, 4-9%, ⩾10%). Hb increased significantly in all three groups. The mean increase in Hb was greater (0-3%, 0.6±1.2; 4-9%, 1.2±1.0; ⩾10%, 1.6±1.4; P=0.02) and the proportion of patients showing a ⩾1 g/dl increase in Hb was greater (0-3%, 27%; 4-9%, 47%; ⩾10%, 67%; P=0.02) in those with the largest %HRC pre-treatment. Conclusion: Intravenous iron therapy is effective in improving Hb in anaemic HD patients with a low ferritin. However, the magnitude of this response and the proportion of patients responding is related to the percentage hypochromic red cells prior to treatment.     

Does long-term treatment of renal anaemia with recombinant erythropoietin influence oxidative stress in haemodialysed patients?

Background. Patients with end-stage renal failure undergoing haemodialysis (HD) are exposed to oxidative stress. Increased levels of malondialdehyde (MDA) were demonstrated in plasma of uraemic patients, indicating accelerated lipid peroxidation (LPO) as a consequence of multiple pathogenetic factors. The aim of our investigation was to examine the role of renal anaemia in oxidative stress in HD patients. Methods. MDA and 4-hydroxynonenal (HNE) were measured in three groups of patients undergoing HD: group I comprised eight patients with a blood haemoglobin (Hb) <10 g/dl (mean Hb=8.1±1.3 g/dl), and group II were eight patients with a Hb <10 g/dl (mean Hb=12.4±1.9 g/dl); none of these 16 patients had been treated with human recombinant erythropoietin (rHuEpo). Group III comprised 27 patients with a mean Hb of 10.5±1.6 g/dl after long-term rHuEpo treatment. Results. Mean plasma concentrations of both MDA and HNE were significantly higher (P<0.0001) in all 43 HD patients than in 20 healthy controls (MDA 2.85±0.25 vs 0.37± &mgr;M, HNE 0.32± vs 0.10±0.01 &mgr;M). Comprising the three groups, it was shown that HD patients with a Hb <10 g/dl had significantly higher plasma levels of LPO products (MDA 3.81±0.86 &mgr;M, HNE 0.45±0.07 &mgr;M) than HD patients with a Hb > 10 g/dl (MDA 2.77±0.58 &mgr;M, HNE 0.25±0.05 &mgr;M), and than HD patients treated with rHuEpo (MDA 2.50±0.12 &mgr;M, HNE 0.29±0.03 &mgr;M). Furthermore, an inverse correlation between plasma concentration of LPO products and haemoglobin levels was seen (r=0.62, P<0.0001). Conclusion. Radical generation in HD patients might be caused in part by renal anemia itself. Treatment with rHuEpo may decrease radical generation effectively in HD patients due to the increase in the number of red blood cells and blood haemoglobin concentration. Keywords: erythropoietin; haemodialysis; HNE; lipid peroxidation; MDA; renal anaemia      

Clinical morbidity in pediatric dialysis patients: data from the Network 1 Clinical Indicators Project

The Health Care Financing Administration (HCFA) has gathered clinical data on end stage renal disease (ESRD) patients since 1994, but details are only available on patients ≥18 years. In this report, we present morbidity data collected prospectively over 12 months from all children (1–18 years) maintained on either hemodialysis (HD) or peritoneal dialysis (PD) within the six-state New England area. During this year, 17 observations were recorded on 14 HD patients (age 13.4± 11.3 years) and 36 observations were made on 25 PD patients (age 11.5±4.8 years; mean ± SD). These patients were generally highly functional, attending school at least part time in nearly all cases. Dialysis adequacy index (DAI), defined as the delivered KT/V divided by DOQI guideline values, indicated that patients were well dialyzed (HD 1.41±0.1 and PD 1.10±0.1; mean ± SE). When all dialysis patients were grouped and analyzed, the DAI did not correlate with number of hospitalizations, degree of anemia, serum albumin, or type of dialysis. The number of hospitalizations were greater the younger the patient (P<0.01). The need for antihypertensive medications was higher in the children maintained on HD (94%) compared to children on PD (58%) (P<0.01). Lastly, while serum ferritin did not correlate with serum iron, hematocrit or Epo dosage, it was inversely related to serum albumin (P<0.03). We conclude that, in children, (1) exceeding suggested dialysis adequacy may not improve patient morbidity, (2) the need for antihypertensive medications appears greater in children maintained on HD, and (3) inflammation may play a role in determining serum albumin independent of nutrition. Received: 3 April 2001 / Revised: 26 June 2001 / Accepted: 10 July 2001     

Asymmetric Dimethylarginine in Hemodialysis,Hemodiafiltration, and Peritoneal Dialysis

Asymmetric dimethylarginine (ADMA) is a mediator of endothelial dysfunction. Production and elimination of ADMA may be affected by the type of renal replacement therapy used and oxidative stress. Plasma ADMA, advanced glycation end products (AGE), and homocysteine were assessed in 59 subjects: 20 hemodialysis (HD) patients, 19 patients undergoing peritoneal dialysis (PD), and 20 controls. Results were compared between the groups. The effect of 8 weeks of HD and high‐volume predilution hemodiafiltration (HDF) was compared in a randomized study. HD patients showed higher ADMA (1.20 [0.90–1.39 µmol/L]) compared to controls (0.89 [0.77–0.98], P < 0.01), while ADMA in PD did not differ from controls (0.96 [0.88–1.28]). AGE and homocysteine were highest in HD, lower in PD (P < 0.01 vs. HD), and lowest in controls (P < 0.001 vs. HD and PD). PD patients had higher residual renal function than HD (P < 0.01). The decrease in ADMA at the end of HD (from 1.25 [0.97–1.33] to 0.66 [0.57–0.73], P < 0.001) was comparable to that of HDF. Switching from HD to HDF led to a decrease in predialysis homocysteine level in 8 weeks (P < 0.05), while ADMA and AGE did not change. Increased ADMA levels in patients undergoing HD, as compared to PD, may be caused by higher oxidative stress and lower residual renal function in HD. Other factors, such as diabetes and statin therapy, may also be at play. The decrease in ADMA at the end of HD and HDF is comparable. Switching from HD to HDF decreases in 8 weeks the predialysis levels of homocysteine without affecting ADMA.     

Reduction of left ventricular hypertrophy in children undergoing hemodialysis

Left ventricular hypertrophy (LVH) is related to a 1,000-fold increased risk of cardiovascular morbidity and mortality in young adults with end-stage renal disease (ESRD) treated with hemodialysis (HD) or peritoneal dialysis. We report a series of 17 children (5 girls, 12 boys), with a median (range) age of 11 (2–18) years, all treated by HD, who presented with an increased left ventricular mass (LVM) index of 54.8±4.5 g/m^2.7 at onset of HD and reached 36.2±2.6 g/m^2.7 (mean±SEM, P<0.0001) at last follow up. Over the observation period, systolic (P<0.0001) and diastolic (P<0.0001) blood pressure (indexed for height, gender, and age) decreased and hemoglobin (+2.8 g/dL; P<0.0001) increased compared to initial values. Only BP as well as plasma protein level at onset of HD session correlated with LVM in multiple correlation analysis. In conclusion, increased LVM is a common feature in pediatric patients with ESRD. Normalization of BP and reduction of the extracellular volume (represented by plasma protein at onset of HD session) are key points in reducing LVH during HD in children.     

Transfusion and recombinant human erythropoietin requirements differ between dialysis modalities

Background: Before the routine use of recombinant human erythropoietin (rHuEpo), patients dialysed by peritoneal dialysis (PD) received fewer blood transfusions than patients on haemodialysis (HD). We compared transfusion practices in these groups now that the use of rHuEpo has become standard, while controlling for variables known to influence anaemia of end-stage renal disease (ESRD). Maintenance rHuEpo doses were also compared. Methods: Data were examined for 157 HD and 126 PD patients during a 2-year period. Potential confounders included age, gender, albumin, iron deficiency, parathyroid hormone (PTH), underlying renal disease, cormorbid illness, renal transplant, dialysis adequacy and duration. An intent-to-treat analysis was used, with sensitivity analyses to account for change in treatment and transplant. Results: Mean haemoglobin (Hb) was not different (10.47 g/dl for HD, 10.71 G/DL for PD; P=0.45). Mean monthly transfusion rate was higher for HD (0.47 units per month vs 0.19; P<0.01). More HD patients received at least one transfusion (52.9 vs 40.9%; P<0.01). The maintenance rHuEpo dose was higher for HD (7370 U/week vs 5790 U/week; P=0.01). The only factors associated with risk of being transfused were dialysis duration and mode of dialysis (less risk for PD, odds-ratio 0.57; 95% confidence interval 0.35-0.92). Conclusions: Despite the routine use of rHuEpo, HD patients received more blood and rHuEpo than PD patients to achieve the same Hb. No patient factors were identified to account for this difference. The use of fewer transfusions and less rHuEpo in PD represents an advantage over HD in terms of both cost and safety.     

Brain Natriuretic Peptide and Its Relationship to Left Ventricular Hypertrophy in Patients on Peritoneal Dialysis or Hemodialysis Less Than 3 Years

An increase of brain natriuretic peptide (BNP) levels is commonly observed in patients on dialysis. Increased circulating levels of BNP are related to future cardiac events and associated with shorter survival in patients on chronic hemodialysis (HD). During the first 1 or 2 years on dialysis, patients on peritoneal dialysis (PD) have been shown to have an improvement in left ventricular hypertrophy, blood pressure, and volume status. This study compares BNP levels and cardiac status of PD and HD patients without cardiovascular disease and on dialysis for less than 36 months. The correlation between plasma BNP concentration and findings of echocardiography before HD scans were examined and compared with findings of PD. Twenty-two HD patients (15 men, 7 women; mean age, 52.5 ± 13.9 years) and 19 PD patients (10 men, 9 women; mean age, 47.6 ± 11.3 years) were studied. There were no significant differences between HD and PD patients with regard to age, gender, duration of dialysis, left ventricular mass, left ventricular mass index (p > 0.05). Plasma BNP levels were markedly greater in HD patients (467.8 ± 466.5 pg/mL) than those of PD patients (143.1 ± 165.2 pg/mL). Urine output was significantly higher in PD patients compared with HD patients (p < 0.05). A positive correlation between systolic blood pressure, diastolic blood pressure, and plasma BNP in HD patients (r: 0.653, p: 0.001; r: 0.493, p: 0.023, respectively) was detected. Additional studies are needed to investigate whether lower BNP level in PD patients is an advantage.     

Abnormal left ventricular mass and aortic distensibility in pediatric dialysis patients

There is ample evidence that the same pathophysiological processes that affect cardiovascular function in adults with end-stage renal disease (ESRD) also operate in children with ESRD. In adults undergoing hemodialysis (HD), a good correlation has been established between left ventricular mass (LVM) and aortic distensibility (AD) as markers of cardiovascular disease progression; however, this correlation has not been established in children. Therefore, in this retrospective study we investigated some aspects of cardiovascular damage (i.e., LVM, LVMI, and AD) in children with ESRD undergoing HD ( n =9) or peritoneal dialysis (PD, n =9), and analyzed the relationship between AD, LVM, LVMI, pre-dialysis, post-dialysis blood pressure (BP), and demographic factors in children and adolescents with ESRD. Both LVM and AD were significantly greater in the dialysis population than in a control population derived from our institutional files ( P =0.015, P =0.001). LVM and LVMI in children undergoing HD (92.9±83.7 g, 80.1±31.1 g/cm) were not statistically different from the values in children on PD (130.0±89.2 g, 89.6±35.9 g/cm), ( P =0.3, P =0.5). AD in children on HD (2.2±0.55 cm² * dynes^–1*10–6) was significantly lower than in children on PD (2.7±0.54 cm² * dynes^–1*10–6), ( P =0.01). The findings in this study confirm earlier studies that demonstrated that LVMI is greater in children on dialysis. This study also demonstrates that abnormal vascular stiffness, as defined by AD, is present in these children. The degree of vascular stiffness in children receiving HD is greater than in children receiving PD. However, further study is needed to address how control of BP, uremia, and other factors may affect these abnormalities in children with ESRD.     

Correction of metabolic acidosis increases serum albumin concentrations and decreases kinetically evaluated protein intake in haemodialysis patients: a prospective study

Background: Metabolic acidosis in haemodialysis (HD) patients increases whole body protein degradation while the correction of acidosis reduces it. However, the effects of the correction of acidosis on nutrition have not been clearly demonstrated. Study design: In this study we have evaluated the effects of 3 months of correction of metabolic acidosis by oral sodium bicarbonate supplementation on protein catabolic rate (PCRn) and serum albumin concentrations in 12 uraemic patients on maintenance HD for at least 6 months (median 49 months; range 6-243 months). Pre-dialysis serum bicarbonate, arterial pH, serum albumin, total serum proteins, serum creatinine, plasma sodium, haemoglobin, PCRn, Kt/V, and TACurea, were evaluated before and after correction. Results: Serum bicarbonate levels and arterial pH increased respectively from 19.3±0.6 mmol/l to 24.4±1.2 mmol/l (P<0.0001) and 7.34±0.03 to 7.40±0.02 (P<0.0001). Serum albumin increased from 34.9±2.1 g/l to 37.9±2.9 g/l (P<0.01) while PCRn decreased from 1.11±0.17 g/kg/day to 1.03±0.17 g/kg/day (P<0.001). No changes in Kt/V, total serum proteins, serum creatinine, plasma sodium, haemoglobin, body weight, pre dialysis systolic and diastolic blood pressure, and intradialytic weight loss were observed. Conclusions: Our data demonstrate that correction of metabolic acidosis improves serum albumin concentration in HD patients. The correction of acidosis induced a decrease in PCRn values, as evaluated by kinetic criteria, suggesting that in the presence of moderate to severe acidosis this parameter does not reflect the real dietary protein intake of the patients probably as a result of increased catabolism of endogenous proteins. The correction of metabolic acidosis should be considered of paramount importance in HD patients.     

Apolipoprotein A, fibrinogen, age, and history of stroke are predictors of death in dialysed diabetic patients: a prospective study in 412 subjects

Background: diabetic patients with end-stage renal failure (ESRD) have a high cardiovascular morbidity and mortality. The underlying mechanisms are not completely elucidated. The aim of our study was to define predictors of death in diabetic patients with end-stage renal disease. Patients and methods: We preformed a prospective study in 35 dialysis centres in Germany between 1985 and 1994. To evaluate predictors and risk factors in this population we examined 412 diabetic patients at the time of admission to dialysis treatment (peritoneal dialysis (PD) or haemodialysis (HD)). Classification of the type of diabetes was done according the criteria of the National Diabetes Data Group [1,2]. Items assessed at the time of admission were coronary artery disease (CAD), peripheral occlusive disease (POD), and stroke. CAD was defined as a history of myocardial infarction with the corresponding changes in the ECG or luminal narrowing by more than 50% in at least one coronary artery upon coronarangiography; POD was defined as claudication and/or brachial-tibial ratio (BTR) less than 0.9 or a history of amputation. Assessment of the nutritional state comprised body mass index, skinfold thickness of the upper arm and lateral thorax area, and urea concentration. Cholesterol, HDL, LDL, apolipoprotein A (ApoA-I) and B (ApoB), triglycerides, lipoprotein (a) (Lp(a)), and fibrinogen were measured. As an index of disturbed cardiac innervation beat-to-beat variation was measured. Outcome measurements were causes of death (i.e. cardiac and non-cardiac) and time of survival. Results: One hundred and eighty of 412 (44%) patients died during the observation period Patients who died were older (61±12 versus 53±15 years P lt;0.0001), had lower skin fold thickness (13.1±6.0 versus 15.1±7.2 mm P <0.04), lower ApoA-I (100±35 versus 111±32 mg/dl P <0.005) and higher fibrinogen (515±156 versus 451±155 mg/dl P <0.02). Type II diabetic patients had a lower mean survival time than type I (34 versus 66 months P <0.0006). The mode of renal replacement therapy (PD or HD) had no adverse effect on survival time. Survivors less frequently had a history of CAD, POD and stroke than non-survivors. In multivariate analysis ApoA-I, fibrinogen ,age and stroke were independent predictors of cardiac and non-cardiac death in diabetic patients with end-stage renal failure. Lipid values and nutritional state did not independently predict the overall and cardiovascular mortality. Conclusion: This study in dialysed diabetic patients identified several predictors of death, some of which are susceptible to intervention.     

High dose enalapril impairs the response to erythropoietin treatment in haemodialysis patients

Background: The resistence to recombinant human erythropoietin (rHuEpo) therapy in haemodialysis (HD) patients has multifactorial aetiologies; erythropoietin insufficiency, dialysis insufficiency, iron deficiency, and secondary hyperparathyroidism. Angiotensin-converting enzyme (ACE) inhibitors induce anaemia in patients with essential hypertension, congestive heart failure, chronic renal insufficiency, and renal transplants. Data exist suggesting that ACE inhibitors impair erythropoiesis in HD patients. Therefore the aim of this study was to investigate the impact of enalapril on rHuEpo requirement. Methods: In the present prospective non-randomized study of 12 months, we compared the effects of enalapril and nifedipine on rHuEpo requirement in 40 hypertensive patients receiving rHuEpo for more than 6 months on maintenance haemodialysis. Twenty normotensive rHuEpo-dependent patients served as a control group. All patients with severe hyperparathyroidism or iron deficiency were excluded. The mean (±SD) haemoglobin concentration was >10 g/dl in all groups. The mean weekly rHuEpo dose increased in the enalapril group (P<0.0001 vs before) and remained constant in the nifedipine and control groups (P=NS vs before). Statistically, there was no differences with regard to iPTH levels, dialysis parameters, iron status, and underlying renal diseases among all groups. Conclusion: High-dose enalapril increases rHuEpo requirement and should be reserved for dialysis patients with hypertension uncontrollable with other antihypertensive medications or dialysis patients with cardiac failure.     

Growth of children following the initiation of dialysis: a comparison of three dialysis modalities

Maintenance dialysis usually serves as an interim treatment for children with end-stage renal disease (ESRD) until transplantation can take place. Some children, however, may require dialytic support for an extended period of time. Although dialysis improves some of the problems associated with growth failure in ESRD (acidosis, uremia, calcium, and phosphorus imbalance), many children continue to grow poorly. Therefore, three different dialysis modalities, continuous ambulatory peritoneal dialysis (CAPD), cycler/intermittent peritoneal dialysis (CPD), and hemodialysis (HD), were evaluated with regard to their effects on the growth of children initiating dialysis and remaining on that modality for 6–12 months. Growth was best for children undergoing CAPD when compared with the other two modalities with regard to the following growth parameters: incremental height standard deviation score for chronological age [–0.55±2.06 vs. –1.69±1.22 for CPD (P<0.05) and –1.80±1.13 for HD (P<0.05)]; incremental height standard deviation score for bone age [–1.68±1.71 vs. –2.45±1.43 for CPD (P=NS) and –2.03±1.28 for HD (P=NS)]; change in height standard deviation score during the dialysis period [0.00±0.67 vs. –0.15±.29 for CPD (P=NS) and –0.23±.23 for HD (P=NS)]. The reasons why growth appears to be best in children receiving CAPD may be related to its metabolic benefits: lower levels of uremia, as reflected by the blood urea nitrogen [50±12 vs. 69±16 mg/dl for CPD (P<0.5) and 89±17 for HD (P<0.05)], improved metabolic acidosis, as indicated by a higher serum bicarbonate concentration [24±2 mEq/l vs. 22±2 for CPD (P<0.05) and 21±2 for HD (P<0.05)]. In addition, children undergoing CAPD receive significant supplemental calories from the glucose absorbed during dialysis. CAPD, and possibly, other types of prolonged-dwell daily peritoneal dialysis appear to be most beneficial for growth, which may be of particular importance for the smaller child undergoing dialysis while awaiting transplantation.     

Dialysis as a bridge therapy to renal transplantation: comparison of graft outcomes according to mode of dialysis treatment

Background

Renal transplantation is the ideal renal replacement therapy in patients with end-stage renal disease. It was unclear whether a difference in dialysis modality influences outcomes after kidney transplantation. Therefore, we evaluated the influence of dialysis modality.

Methods

We compared various clinical and laboratory parameters of 70 peritoneal dialysis (PD) and 180 hemodialysis (HD) patients (n = 250), including 91 females and an overall age 36.7 ± 9.7 years who underwent transplantation between 2000 and 2008 to evaluate factors affecting delayed graft function (DGF) and of transplant graft failure.

Results

Overall graft survival was 82% at 3 and 75% at 5 years. Among HD patients, 16% displayed DGF, versus 12% of PD patients. Multivariate analysis showed that factors affecting DGF were: mode of dialysis (relative risk [RR] = 1.39, 95% confidence interval (CI): 1.35-1.43; P < .01); parathyroid hormone (RR = 0.32, 95% CI: 0.30-0.34, P < .05), C-reative protein (RR = 1.03, 95% CI: 0.97-1.09; P < .05), hemoglobin levels (RR = .75, 95% CI: 0.72-0.79; P < .05). At 3 and 5 years follow-up, PD patients' showed fewer graft failures than HD patients (14% vs 20%; P < .05 and 17% vs 28%; P < .05).

Conclusion

Early graft function rates were better for PD than for HD patients. Inflammation and anemia should be carefully investigated and corrected to achieve better graft function.     

The Prevalence of Left Ventricular Hypertrophy in Chinese Hemodialysis Patients Is Higher Than That in Peritoneal Dialysis Patients

Background. Left ventricular hypertrophy (LVH) is common in dialysis patients, and an independent predictor of mortality. While recent studies have shown no differences in mortality between the two most common dialysis modalities, hemodialysis (HD) and peritoneal dialysis (PD), their impact on LVH is controversial. We thus performed cardiac ultrasound studies in prevalent dialysis patients receiving either HD or PD and compared LVH. Methods. We included 48 HD and 62 PD patients receiving treatment for at least three months in our dialysis center. All patients underwent echocardiographic examination and blood pressure measurements immediately following therapy. Volume status was assessed by bioelectrical impedance analysis. Results. There was no baseline difference in demographics or comorbidities between HD and PD patients. As expected, extracellular water (ECW) in post-HD patients was significantly lower than that in pre-HD and PD patients, while cardiac output (CO) and systolic blood pressure (SBP) were higher in pre-HD than that in post-HD or PD patients. There was no significant difference in CO or SBP between post-HD and PD patients. Left ventricular mass index (LVMI) was markedly higher in HD patients as compared to PD patients. Thus, the prevalence of LVH according to the Framingham criteria was 68.8% in HD patients and 45.2% in PD patients. Subgroup analysis showed similar results in the patients who had been on single-modality dialysis for at least two years and in the anuric patients. Finally, in a linear regression model (r² = 0.364, p < 0.001), SBP, treatment modality (to be in HD), and ECW were all independent predictors of LVMI. Conclusions. In a cross-sectional analysis of prevalent Chinese patients, we found a higher LVMI and a higher prevalence of LVH in HD than in PD patients. As LVMI was associated with high blood pressure and volume overload, we suggest that in these patients, PD may preserve more physiological hemodynamics even during long-term therapy.     

Low-density lipoprotein subfraction profiles in chronic renal failure

Background: Small low-density lipoprotein (LDL) particle size, a newly recognized risk factor for cardiovascular disease in the general population, is frequently associated with hypertriglyceridaemia, the predominant plasma lipid abnormality present in uraemia. Methods: Plasma lipids and LDL subfraction profiles were examined in 33 non-dialysed patients with chronic renal failure (predial), 40 patients on continuous ambulatory peritoneal dialysis (CAPD), 42 haemodialysis patients (HD), 47 renal transplant recipients (RTR), and 44 controls. LDL subfractions separated by gel electrophoresis were scored by densitometric analysis (higher scores indicate profiles comprising smaller particles). Results: All groups with renal failure had significantly elevated (mean±SD) LDL scores (predial 1.36±0.6, CAPD 1.71±0.9, HD 1.68±0.9, RTR 1.92±0.8 vs control 0.87±0.4, all P<0.001), this being the only lipid abnormality detected in the predialysis patients. In CAPD and HD patients, LDL scores were associated with serum triglyceride (r=0.81, P<0.0001 and r=0.70, P<0.01 respectively), cholesterol (r=0.55, P<0.001 and r=0.49, P<0.01) and HDL-cholesterol (r=-0.43, P<0.01 and r=-0.51, P<0.01), whilst no such relationship was seen in the predialysis and RTR groups, suggesting that other factors were important. Conclusions: The presence of small LDL particles appears to be an early and unexplained feature of the uraemic dyslipidaemia. This abnormality persists after renal transplantation and may represent an important atherogenic risk factor. Key words: LD subfractions; renal failure; transplants      

Dialysis modality and sexual dysfunction in male patients

Sexual dysfunction is an under-recognised problem in due to very limited number of studies in the literature. This study aims to evaluate the sexual dysfunction related effects of dialysis modality among male patients with chronic renal failure. All patients were asked to complete 2 questionnaires: Hospital Anxiety Depression Scale [HADS] and International Index of Erectile Function [IIEF-5]. A total of 51 patients who completed the questionnaires were included in the study. 31 of them were under haemodialysis (HD) treatment, and 20 were under peritoneal dialysis (PD) treatment. After adjustment for age and HADS score, there was no statistically significant difference between HD and PD groups in terms of the mean IIEF scores (55 vs. 40, p = .058), and the frequency of sexual dysfunction (12.9% vs. 30%, p = .163). Age (r = −0.553), blood pressure (r = −0.299/ −0.374), use of iron (r = −0.333), lipid levels (r = −0.281/ −0.276) and HADS-D score (r = −0.276) inversely associated with IIEF score (p < .05). To conclude, sexual dysfunction is more common in patients who receive PD therapy than those who receive HD therapy. Older age, higher blood pressure, iron treatment, higher lipid levels and the presence of depression were associated with higher prevalance of sexual dysfunction.