Long-term effects of magnesium carbonate on coronary artery calcification and bone mineral density in hemodialysis patients: A pilot study

Observational data suggest that elevated magnesium levels in dialysis patients may prevent vascular calcification and in vitro magnesium can prevent hydroxyapatite crystal growth. However, the effects of magnesium on vascular calcification and bone mineral density have not been studied prospectively. Seven chronic hemodialysis patients participated in this open label, prospective pilot study to evaluate the effects of a magnesium-based phosphate binder on coronary artery calcification (CAC) scores and vertebral bone mineral density (V-BMD) in patients with baseline CAC scores >30. Magnesium carbonate/calcium carbonate (elemental Mg: 86 mg/elemental Ca 100 mg) was administered as the principal phosphate binder for a period of 18 months and changes in CAC and V-BMD were measured at baseline, 6, 12, and 18 months. Serum magnesium levels averaged 2.2±0.4 mEq/L (range: 1.3–3.9 mEq/L). Phosphorus levels (4.5±0.6 mg/dL) were well controlled throughout the 18 months study. Electron beam computed tomography results demonstrated a small not statically significant increase in absolute CAC scores, no significant change in median percent change, and a small none significant change in V-BMD. Magnesium may have a favorable effect on CAC. The long-term effect on bone mineral density remains unclear. Larger studies are needed to confirm these findings.     

Both pelvic radiography and lateral abdominal radiography correlate well with coronary artery calcification measured by computed tomography in hemodialysis patients: A cross‐sectional study

Introduction Lateral abdominal radiograph is suggested as an alternative to coronary artery computed tomography (CT) in evaluating vascular calcification. Simple scoring systems including pelvic radiograph scoring and abdominal scoring system were utilized to study their correlation with coronary artery calcification. Methods In 106 MHD patients, coronary artery CT, lateral abdominal, and pelvic radiograph were taken. The Agatston scoring system was applied to evaluate the degree of coronary artery calcification which was categorized according to Agatston coronary artery calcification score (CACS) ≥ 30, ≥100, ≥400, and ≥1000. Abdominal aortic calcification was scored by 4‐scored and 24‐scored systems. Pelvic artery calcification was scored by a 4‐scored system. Sensitivities and specificities of abdominal aortic calcification scores and pelvic artery calcification scores to predict different categories of coronary artery calcification were analyzed. We studied the diagnostic capability of abdominal aorta calcification and pelvic artery calcification to predict different CACS categories by calculating likelihood ratios. Receiver operator characteristic curves were used to determine the area under the curve for each of these testing procedures. Findings The prevalence was 48(45.3%), 15 (14.2%), 11 (10.4%), 11 (10.4%), and 11 (10.4%) for CACs > 0, ≥30, ≥100, ≥400, and ≥1000, respectively. The degree of CACs was positively correlated with patient age, prevalence of diabetes, abdominal aorta scores, and pelvic calcification scores. The areas under the curves for different CACS by all X‐ray scoring systems were above 0.70 except pelvic 4‐scored system for diagnosing CACS ≥30, without significant difference (P > 0.05). Discussion Both lateral abdominal and pelvic plain radiographs were demonstrated as acceptable alternatives to CT in evaluating vascular calcification.     

Impact of coronary artery calcification in hemodialysis patients: Risk factors and associations with prognosis

The risk factors of coronary artery calcification (CAC) and the impact of CAC on cardiovascular events, cardiovascular deaths, and all‐cause deaths in hemodialysis (HD) patients have not been fully elucidated. We examined the CAC score (CACS) in 74 HD patients using electron‐beam computed tomography. Fifty‐six patients underwent a second electron‐beam computed tomography after a 15‐month interval to evaluate CAC progression. We evaluated (1) the risk factors for CAC and its progression and (2) the impact of CAC on the prognosis. In the cross‐sectional study, HD vintage and high‐sensitive C‐reactive protein (hsCRP) were the independent risk factors for CAC. In the prospective cohort study, delta CACS (progression of CAC) was significantly correlated with hsCRP, fibrinogen, and serum calcium level in the univariate analysis. Stepwise multiple regression analysis revealed that only hsCRP was the independent risk factor for CAC progression in HD patients. Kaplan‐Meier survival analysis revealed that cardiovascular events (P<0.0001), cardiovascular deaths (P=0.039), and all‐cause deaths (P=0.026) were significantly associated with CACS. In conclusion, CAC had significantly progressed in HD patients during the 15‐month observation period. Microinflammation was the only independent risk factor for CAC progression in HD patients. The advanced CAC was a significant prognostic factor in HD patients, i.e., which was strongly associated with future cardiovascular events, cardiovascular deaths, and all‐cause deaths.     

Intracranial arterial calcification is highly prevalent in hemodialysis patients but does not associate with acute ischemic stroke

Intracranial arterial calcification (IAC) is associated with ischemic stroke in the general population but this relationship has not been examined in hemodialysis patients. We examined the factors associated with IAC and its relationship with acute ischemic stroke in this population. We retrospectively studied 490 head computed tomographic scans from 2225 hemodialysis patients presenting with neurological symptoms at our center (October 2005-May 2009). Intracranial arterial calcification was graded using a validated scoring system. Multivariate regression was used to examine the factors associated with the presence of IAC, its severity, and its ability to predict acute ischemic stroke. Weibull's survival models analyzed the relationship between IAC severity and survival. Ninety-five percent of patients with ischemic stroke had IAC vs. 83% in the nonstroke group (P=0.02). Intracranial arterial calcification severity increased with age (P<0.001), hemodialysis vintage (P<0.001), serum phosphate (P<0.05), and major comorbidities. In patients with multiple computed tomographic scans during the study period, increased IAC severity at baseline was predictive of acute ischemic stroke (P=0.05) on logistic regression analysis. High-grade and not low-grade IAC was associated with worse survival (P=0.008). Intracranial arterial calcification is highly prevalent in hemodialysis patients, especially in those with acute ischemic stroke. Its severity is prognostically significant and associated with risk factors for vascular calcification and may confer a greater risk of acute ischemic stroke. The mechanisms underlying the high incidence of ischemic stroke in this patient group require further comprehensive study.     

Risk of major depression in patients with chronic renal failure on different treatment modalities: A matched‐cohort and population‐based study in Taiwan

The influence of different treatment modalities on the risk of developing major depression in patients with chronic renal failure (CRF) is not well understood. We aimed to explore the incidence of major depression among patients with CRF who were on different dialysis modalities, who had received renal transplantation (RT), and those who had not yet received any of the aforementioned renal replacement therapies. We conducted a population‐based retrospective cohort study using a national health insurance research database. This study investigated 89,336 study controls, 17,889 patients with chronic kidney disease on conservative treatment, 3823 patients on hemodialysis (HD), 351 patients on peritoneal dialysis (PD), and 322 patients who had RT. We followed all individuals until the occurrence of major depression or the date of loss to follow‐up. The PD group had the highest risk (hazard ratio [HR] 2.43; 95% confidence interval [CI] 1.26–4.69), whereas the RT group had the lowest risk (HR 0.18; 95% CI 0.03–1.29) of developing major depression compared with the control group. Patients initiated on PD had a higher risk of developing major depression than patients initiated on HD (pairwise comparison: HR 2.20; 95% CI 1.09–4.46). Different treatment modalities are associated with different risks of developing major depression in patients with CRF. Among renal replacement therapies, patients who have had RT have the lowest risk of developing major depression. Patients who initiate renal therapy on PD may have a higher risk of major depression compared with patients who initiate renal therapy on HD.     

Pulmonary hypertension in patients on chronic hemodialysis and with heart failure

Pulmonary hypertension (PH) is linked to chronic kidney disease. However, few studies have examined the prevalence, risk factors, or outcomes of PH in patients with chronic hemodialysis and concomitant heart failure. This retrospective cohort study enrolled 160 patients with a history of acute decompensated heart failure after maintenance hemodialysis therapy. All patients were prospectively observed until December 2013 or death. PH was defined as pulmonary artery systolic pressure >35 mmHg, as determined through echocardiography. Fifty‐one (32%) patients had PH, more of whom were female (70% vs. 52%, P = 0.04). The patients with PH had a lower body mass index (21.8 vs. 23.0, P = 0.03), higher cardiothoracic ratio (55% vs. 52%, P = 0.006), larger left atrium (38.5 vs. 35.7 mm, P = 0.01), and an increased proportion of mitral regurgitation (MR) (73% vs. 38%, P < 0.001) compared with the patients who did not have PH. In the multivariate regression analysis, MR was associated most strongly with PH (odds ratio 3.75, 95% confidence interval [CI]: 1.67–8.43, P = 0.001). In the multivariate Cox proportional hazard models, PH was related independently to all‐cause mortality (hazard ratio [HR], 3.11; 95% CI, 1.53–6.31; P = 0.002) and combined cardiovascular events (HR, 2.71; 95% CI, 1.66–4.44; P < 0.001) after the model was adjusted for conventional cardiovascular risk factors. PH is related to MR and independently associated with increased all‐cause mortality and cardiovascular events in patients with chronic hemodialysis and heart failure.     

Effect of hemodiafiltration with endogenous reinfusion on overt idiopathic chronic inflammation in maintenance hemodialysis patients: A multicenter longitudinal study

Chronic inflammation is widely diffuse in maintenance hemodialysis (MHD) patients and is associated with poor survival. Hemodiafiltration with endogenous reinfusion (HFR) is a dialysis technique, highly biocompatible, able to adsorb proinflammatory cytokines and to decrease amino acids and antioxidants loss. These features could be helpful in MHD patients affected by idiopathic chronic inflammation, but this issue remains to be elucidated. We performed a multicenter longitudinal study to assess the effect of the switching from bicarbonate HD to HFR in patients with serum C‐reactive Protein (CRP) > 5 mg/L coupled with albumin <4.0 g/dL in the last 6 months. We enrolled 24/176 (14%) patients, of which 20 patients were assessed at 4 months and 18 completed the study. We excluded 11 patients with evident causes of inflammation. At baseline, serum levels of CRP (18.7[7.0–39.4] mg/L) and albumin (3.5[3.3–3.7] g/dL) were significantly correlated (r = ?0.49; P = 0.028). The effect on CRP and albumin was almost evident in the first 4 months and remained stable until to eighth month. A strict correlation (R = ?0.49; 0.040) between percentage change of CRP (?35%) and albumin (+14%) after 8 months of HFR. These effects were associated with the reduction of IL‐6, IL‐1β, and TNF‐α and the increment of pre‐albumin and leptin, whereas the serum levels of Branched Chain Amino Acid (BCAA) remained unchanged. In MHD patients affected by idiopathic chronic inflammation the switching from BHD to HFR is associated with improvement of inflammation. Whether these favorable effects may modify the outcomes of these high‐risk patients needs to be confirmed by studies ad hoc.     

Effect of sevelamer on aortic pulse wave velocity in patients on hemodialysis: a prospective observational study

Aortic stiffening and aortic calcification are risk factors for cardiovascular events in hemodialysis (HD) patients, and these 2 risk factors are interrelated. Sevelamer decreases aortic calcification but its effect on aortic stiffness has not been investigated previously. Thirteen HD patients commencing sevelamer treatment and 13 matched controls were followed for 11 months. Aortic pulse wave velocity (PWV), augmentation index (AIx), and levels of inhibitors of vascular calcification (fetuin-A, matrix-GLA-protein, osteoprotegerin/RANKL) were measured at baseline and at the end of follow-up, and the differences between the groups were compared. Determinants of the changes in PWV during follow-up were assessed by multivariate linear regression. At baseline, PWV was 9.93 (2.10) m/s in sevelamer-treated patients and 9.20 (2.84) m/s in control patients (p=0.464). By the end of follow-up, PWV decreased by 0.83 (2.3) m/s in sevelamer-treated patients while it increased by 0.93 (1.88) m/s in controls (p=0.042). The direction of changes in AIx were similar, but not statistically significant. There were no significant differences in the levels of inhibitors of calcification either at baseline or during follow-up. In multivariate linear regression sevelamer treatment, diabetes, heart rate, and C-reactive protein were related to the change in PWV. These data suggest that sevelamer treatment is associated with an improvement in aortic stiffness in HD patients, but it does not seem to affect serum levels of inhibitors of vascular calcification.     

The relationship between neutrophil‐to‐lymphocyte ratio and vascular calcification in end‐stage renal disease patients

Chronic inflammation was found to be correlated with coronary (CAC) and thoracic peri‐aortic calcification (TAC) in end‐stage renal disease (ESRD) patients. Neutrophil‐to‐lymphocyte ratio (NLR) was introduced as a potential marker to determine inflammation in cardiac and noncardiac disorders. Data regarding NLR and its association with TAC and CAC are lacking. We aimed to determine the relationship between NLR and vascular calcification in ESRD patients. This was a cross‐sectional study involving 56 ESRD patients (22 females, 34 males; mean age, 49.9 ± 14.2 years) receiving peritoneal dialysis or hemodialysis for ≥6 months in the Dialysis Unit of Necmettin Erbakan University. TAC and CAC scores were measured by using an electrocardiogram‐gated 64‐multidetector computed tomography. NLR was calculated as the ratio of the neutrophils and lymphocytes. There was a statistically significant correlation between NLR, TACS and CACS in ESRD patients (r = 0.43, P = 0.001 and r = 0.30, P = 0.02, respectively). The stepwise linear regression analysis revealed that age, as well as NLR were independent predictors of TACS. However, increased age was the only independent predictor of CACS according to linear regression analysis. Simple calculation of NLR can predict vascular calcification in ESRD patients.     

The level of C‐reactive protein in chronic hemodialysis patients: A comparative study between patients with noninfected catheters and arteriovenous fistula in two large Gulf hemodialysis centers

Hemodialysis (HD) patients have greater morbidity and mortality when they have a central venous catheter (CVC) rather than an arteriovenous fistula (AVF) access. Inflammation associated with dialysis catheter use and resultant higher C‐reactive protein (CRP) levels could have an independent adverse effect on patient outcomes. In this prospective study, we investigated whether HD catheters induce inflammation independent of infection. We compared the mean levels of the inflammatory marker (CRP) in 67 patients on maintenance HD using noninfected catheters with 86 HD patients using AVFs at Prince Salman Center for Kidney Diseases, Saudi Arabia (KSA), and Jahra Hospital, Kuwait, who met our inclusion criteria. C‐reactive protein levels were measured every 2 months over a period of 6 months using immunoturbidimetric assay. One hundred fifty‐three patients on maintenance HD for more than 6 months were included in the study, with mean age of 52.19 ± 16.06 years; 66% were males and 34% were females. Serial levels of mean CRP were statistically and significantly higher in group with noninfected catheters (1.33, 1.24, and 1.10 mg/dL) compared to those with AVFs (0.65, 0.59, and 0.68 mg/dL) with P value of 0.000. In our study, we found no relation between CRP level and age, sex, hemoglobin, albumin, calcium, phosphorus, and iPTH level in both groups. Hemodialysis patients with a catheter have a heightened state of inflammation independent of infection, and thus our study supports the avoidance of catheters and a timely conversion to AVFs with catheter removal.     

Outcomes of patients with end‐stage renal disease (ESRD) under chronic hemodialysis requiring continuous renal replacement therapy (CRRT) and patients without ESRD in acute kidney injury requiring CRRT: A single‐center study

In most continuous renal replacement therapy (CRRT) studies, end‐stage renal disease (ESRD) patients were excluded and the outcomes of patients with ESRD treated with chronic hemodialysis (HD) were unknown. The purposes of this study were to (1) evaluate short‐term patient survival and (2) compare the survival of conventional HD patients needing CRRT with the survival of non‐ ESRD patients in acute kidney injury (AKI) requiring CRRT. We evaluated adults (>18 years) requiring CRRT who were treated in the intensive care unit (ICU) at Kosin University Gospel Hospital from January 1, 2009 to December 31, 2010. A total of 100 (24 ESRD, 76 non‐ESRD) patients underwent CRRT during the study period. Patients were divided into two major groups: patients with ESRD requiring chronic dialysis and patients without ESRD (non‐ESRD) with AKI. We compared the survival of conventional HD patients requiring CRRT with the survival of non‐ ESRD patients in AKI requiring CRRT. For non‐ESRD patients, the 90‐day survival rate was 41.6%. For ESRD patients, the 90‐day survival rate was 55.3%. Multivariate Cox proportional hazards analyses demonstrated that conventional HD was not a significant predictor of mortality (hazard ratio [HR]: 0.334, 95% confidence interval [CI]: 0.063–1.763, P = 0.196), after adjustment for age, gender, presence of sepsis, APACHE score, use of vasoactive drugs, number of organ failures, ultrafiltration rate, and arterial pH. The survival rates of non‐ESRD and ESRD patients requiring CRRT did not differ; ESRD with conventional HD patients may be not a significant predictor of mortality.     

Outcome among patients with acute renal failure needing continuous renal replacement therapy: A single center study

Outcome of acute renal failure (ARF) and use of continuous renal replacement therapy (CRRT) have shown a consistently high mortality. (1) Evaluate the short-term patient survival. (2) Evaluate dialysis-free survival. (3) Evaluate risk factors associated with overall survival and the continued need for intermittent dialysis. We identified adults (≥18 years) needing CRRT, treated in the critical care units of Froedtert Medical and Lutheran Hospital from January 1, 2003 till December 31, 2005. Patients were divided into two major groups needing CRRT, end stage renal disease (ESRD) (chronic dialysis) and non-ESRD with ARF. Continuous renal replacement therapy was performed with an average of 2 L replacement fluid exchanges/h. Sigma stat software was used for analysis. Comparison was done for noncontinuous variables by chi-square and t test for categorical and continuous variables, respectively. A total of 110 (ESRD 24/non-ESRD 86) patients received CRRT during study period. Over all in-hospital mortality among non-ESRD patients was 63% vs. 46% for ESRD. Among non-ESRD patients who survived, 47% needed intermittent hemodialysis on intensive care unit discharge and 28% continued to need hemodialysis at last follow-up. Among non-ESRD patients alive at discharge, those who were dialysis dependent on last follow-up were older (64.5) than those who did not require dialysis on last follow-up (58.4) P=0.347. Non-ESRD patients who died were in the hospital for an average of 17.5 days compared with 29 days for those who were discharged from the hospital. Patients with ARF needing CRRT have high in-hospital mortality. A significant percentage of patients remained dialysis dependant on last follow-up.     

Ledipasvir and Sofosbuvir for untreated HCV genotype 1 infection in end stage renal disease patients: A prospective observational study

Introduction: Hepatitis C virus (HCV) infection in end stage renal disease (ESRD) is associated with increased mortality. Recently, numerous directly acting antiviral agents have been approved for the management of HCV. Ledipasvir along with Sofosbuvir has been approved for management of genotype 1 infection in patients with eGFR ≥30 mL/min. However, there is paucity of data regarding its role in the management of patients on dialysis. Material and Methods: This is a single center prospective open label observational study to assess the safety and efficacy of Ledipasvir and Sofosbuvir in hemodialysis (HD) patients who were diagnosed with HCV genotype 1 infection. Eligibility criteria were treatment naive HD patients with normal liver histology. We administered Ledipasvir and Sofosbuvir combination tablet on alternate days for a period of 12 weeks. Primary efficacy end point was the assessment of sustained virological response (SVR12), and the safety end point was the discontinuation of therapy secondary to adverse drug effects. Results: A total of 21 patients were treated with this regimen. Two patients expired during the study period and are not related to the therapy. SVR12 was achieved in all the 19 patients. None of the patients in our study discontinued the therapy or had severe adverse drug effects. One patient had head ache and another patient had giddiness which were managed symptomatically. Conclusion: Ledipasvir and Sofosbuvir combination therapy on alternate days, is effective even in ESRD patients, with excellent SVR12 rates, and it is as safe as in other population groups, without any major adverse reactions.     

Genetic polymorphisms and the risk of progressive renal failure in elderly Hungarian patients

The relationship between renal disease progression and genetic polymorphism of enzymes influencing endothelial function remains incompletely understood. We genotyped three cohorts of elderly Hungarian patients: 245 patients with end‐stage renal disease (ESRD) on chronic hemodialysis (HD), 88 patients with mild chronic kidney disease (CKD), and 200 healthy controls. The underlying diagnoses of renal diseases were primary glomerulonephritis, interstitial nephritis, hypertension, diabetic nephropathy, and hereditary diseases. We examined genetic polymorphisms of eight candidate genes associated with endothelial function: endothelial constitutive nitric oxide synthase (ecNOS) T‐786C, endothelin‐1 G5727T, methylenetetrahydrofolate reductase (MTHFR) C677T, paraoxonase‐1 Q192R and M55L, angiotensinogen M235T, angiotensin‐converting enzyme (ACE) I/D and angiotensin II type 1 receptor A1166C gene. Six gene polymorphisms were detected by real‐time polymerase chain reaction with melting‐point analysis, and two via allele‐specific amplification and gel electrophoresis. Control group patients were in Hardy‐Weinberg equilibrium for all tested genotypes. In ESRD patients attributed to hypertension, the endothelin gene G5727T GG genotype occurred significantly less but GT genotype more frequently (P < 0.01 for both). In ESRD patients attributed to primary glomerulonephritis, more ACE DD and less ID genotypes were found (P < 0.02 for both) than in the controls. The underlying diagnosis may modify the association of genetic polymorphism and dialysis‐dependent ESRD.     

Paraoxonase‐1 (PON1) activity as a risk factor for atherosclerosis in chronic renal failure patients

Paraoxonase is a high‐density lipoprotein‐associated enzyme and has been shown to reduce the susceptibility to low‐density lipoprotein peroxidation. This study aimed to investigate the activity of serum paraoxonase in uremic patients on hemodialysis (HD) and in the predialysis period, and to evaluate the correlations of vascular disease with paraoxonase activity. Thirty patients with chronic renal failure (CRF) undergoing HD (group 1), 30 patients with CRF under conservative treatment (group 2), and 30 healthy controls (group 3) were included. Basal, salt‐stimulated, and arylesterase activity were tested by UV spectrophotometry. Serum lipid parameters were determined. B‐Mode Doppler ultrasound was used to assess common carotid intima‐media thickness (IMT). Basal paraoxonase, salt‐stimulated, and arylesterase activity showed no significant difference between group 1 and group 2. However, it was significantly lower in group 1 and in group 2 than controls. Carotid IMT was significantly higher in group 1 than group 2 and both were significantly higher than controls. Basal paraoxonase‐1 (PON1), salt‐stimulated PON1, and arylesterase activity correlate with BUN, but only basal PON1 and salt‐stimulated PON1 correlate with serum albumin. Linear regression showed that the most significant determinant of carotid IMT was PON1 arylesterase activity in group 1 and arylesterase activity and basal PON1 activity in group 2. Patients with CRF, whether under HD or conservative treatment, have reduced basal and stimulated paraoxonase activities, and this could be an important factor causing increased vascular disease in those patients. Modifying this factor can be of great value to protect against this common complication.     

The possibility of renal function recovery in chronic hemodialysis patients should not be overlooked: Single center experience

Chronic hemodialysis is implemented when irreversible loss of kidney function occurs. Sometimes renal recovery is overlooked. From January 2005 to December 2014, we identified 28 patients hemodialyzed for more than 3 months who had renal replacement therapy discontinued. The group consisted of 17 (57.7%) males and 11 (42.3%) females. Patients were 18–87 years old. Time of hemodialysis ranged from 3 to 97 months. Of note, 14 (50%) patients were referred from local dialysis units for solution of vascular access problems. In 13 (46.2%) patients dialysis was abandoned within the first 6 months, in 5 (17.8%) patients between 6 and 12 months, and in 10 (35.7%) patients beyond 12 months. Estimated dialysis‐free survival was 94.4% (SE 0.054) and 82% (SE 0.095) at 12 and 24 months, respectively. All physicians must be aware of possible kidney function improvement. In patients with preserved diuresis fall in periodical urea or creatinine measurements might be a sign of renal recovery.     

Nervous system autoantibodies and vitamin D receptor gene polymorphisms in hemodialysis patients

Cognitive deficits are prevalent in hemodialysis (HD) patients. Vitamin D deficiency and vitamin D receptor (VDR) gene single nucleotide polymorphism (SNPs) have been linked to both neurodegeneration (ND) and neuroprotection, respectively. Autoantibodies (Ab) to myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and neurofilament (NF) triplet proteins arise secondary to nervous system (NS) damage providing a means to assess neurological injury. Characterization of Ab biomarkers of NS damage in HD patients, their association with VDR SNPs, and nutritional vitamin D (NVD) therapy was performed. VDR genotypes, cytokines, and Ab biomarkers to NS proteins in HD subjects receiving ergocalciferol (n = 40) were compared with nonusers (n = 71). Interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and immunoglobulin G (IgG) titers against NFs, GFAP, and MBP were measured by immunoassay. Subjects were genotyped for VDR SNPs BsmI (rs1544410) and FokI (rs2228570). Subjects (age 63.3 ± 16.1 years, 66% male) who were C allele carriers of BsmI had higher values of NF‐68 antibody titers (p = 0.027). Ergocalciferol users (n = 40) compared with nonusers (n = 71) had lower Ab titers to NS proteins; however, only anti–NF‐160 and anti‐MBP titers were significantly (p < 0.05) higher. IgG against NS proteins in HD patients suggests neuronal and glial insult and a relationship with VDR alleles. NVD may provide some neuroprotection, indicated by anti–NF‐160 and anti‐MBP, which was markedly lowered in ergocalciferol patients. This preliminary study suggests that Ab detection may be useful in monitoring ND and the potential of NVD for neuroprotection in HD patients.     

N‐acetylcysteine may improve residual renal function in hemodialysis patients: A pilot study

Clinical outcomes in chronic dialysis patients are highly dependent on preservation of residual renal function (RRF). N‐acetylcysteine (NAC) may have a positive effect on renal function in the setting of nephrotoxic contrast media administration. In our recent study, we showed that NAC may improve RRF in peritoneal dialysis patients. The aim of the present study was to investigate the effect of NAC on RRF in patients treated with chronic hemodialysis. Prevalent chronic hemodialysis patients with a residual urine output of at least 100 mL/24 hours were included. The patients were administered oral NAC 1200 mg twice daily for 2 weeks. Residual renal function was assessed at baseline and at the end of treatment using a midweek interdialytic urine collection for measurement of urine output and calculation of residual renal Kt/V and glomerular filtration rate (GFR). Residual GFR was measured as the mean of urea and creatinine residual renal clearance. Each patient served as his own control. Twenty patients were prospectively enrolled in the study. Administration of NAC 1200 mg twice daily for 2 weeks resulted in significant improvement in RRF: urine volume increased from 320 ± 199 to 430 ± 232 mL/24 hours (P < 0.01), residual renal Kt/V increased from 0.19 ± 0.12 to 0.29 ± 0.14 (P < 0.01), and residual GFR increased from 1.6 ± 1.6 to 2.4 ± 2.3 mL/minute/1.73 m² (P < 0.01). N‐acetylcysteine may improve RRF in patients treated with chronic hemodialysis.