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Protein intake has been directly associated with kidney growth and function in animal and human observational studies. Protein supply can vary widely during the first months of life, thus promoting different kidney growth patterns and possibly affecting kidney and cardiovascular health in the long term. To explore this further, we examined 601 healthy 6-month-old formula-fed infants who had been randomly assigned within the first 8 weeks of life to a 1-year program of formula with low-protein (LP) or high-protein (HP) contents and compared them with 204 breastfed (BF) infants. At 6 months, infants receiving the HP formula had significantly higher kidney volume (determined by ultrasonography) and ratios of kidney volume to body length and kidney volume to body surface area than did infants receiving the LP formula. BF infants did not differ from those receiving the LP formula in any of these parameters. Infants receiving the HP formula had significantly higher serum urea and urea to creatinine ratios than did LP formula and BF infants. Hence, in this European multicenter clinical trial, we found that a higher protein content of the infant formula increases kidney size at 6 months of life, whereas a lower protein supply achieves kidney size indistinguishable from that of healthy BF infants. The potential long-term effects of a higher early protein intake on long-term kidney function needs to be determined. [ABSTRACT FROM AUTHOR]

Optimal therapy of patients with steroid-resistant primary focal segmental glomerulosclerosis (FSGS) remains controversial. This report describes the initial study design, baseline characteristics, and quality of life of patients enrolled in the FSGS Clinical Trial, a large multicenter randomized study of this glomerulopathy comparing a 12-month regimen of cyclosporine to the combination of mycophenolate mofetil and oral dexamethasone. Patients with age ranging 2-40 years, with an estimated glomerular filtration rate >40 ml/min per 1.73 m2, a first morning urine protein-to-creatinine ratio over one, and resistant to corticosteroids were eligible. The primary outcome was complete or partial remission of proteinuria over 52 weeks after randomization. In all, 192 patients were screened, of whom 138 were randomized for treatment. Ethnic distributions were 53 black, 78 white, and 7 other. By self- or parent-proxy reporting, 26 of the 138 patients were identified as Hispanic. The baseline glomerular filtration rate was 112.4 (76.5, 180.0) ml/min per 1.73 m2, and urine protein was 4.0 (2.1, 5.3) g/g. Overall, the quality of life of the patients with FSGS was lower than healthy controls and similar to that of patients with end-stage renal disease. Thus, the impact of FSGS on quality of life is significant and this measurement should be included in all trials. [ABSTRACT FROM AUTHOR]

Until recently, intravenous cyclophosphamide pulses with oral corticosteroids were regarded standard therapy for proliferative lupus nephritis (LN). Azathioprine, a less toxic alternative, was never proven to be inferior. In the first Dutch lupus nephritis study (enrollment between 1995 and 2001), we randomized 87 proliferative LN patients to either cyclophosphamide pulses (750 mg/m2, 13 pulses in 2 years) combined with oral prednisone (CY) or to azathioprine (2 mg/kg/day in 2 years) combined with intravenous pulses of methylprednisolone (3 × 3 pulses of 1000 mg) and oral prednisone (AZA). After a median follow-up of 5.7 years (interquartile range 4.1–7.2 years), doubling of serum creatinine was more frequent in the AZA group, although not statistically significant (relative risk (RR): 4.1, with 95% confidence interval (95% CI): 0.8–20.4). Relapses occurred more often in the AZA group (RR: 8.8, 95% CI: 1.5–31.8). Creatinine and proteinuria at last visit did not differ between the two treatment arms. Moreover, 88.4% of the patients in the AZA arm were still free of cyclophosphamide treatment. During the first 2 years, the frequency of remission was not different, but infections, especially herpes zoster virus infections (HZV) were more frequent in the AZA group. Parameters for ovarian function did not differ between the two groups. In conclusion, in this open-label randomized controlled trial, cyclophosphamide was superior to azathioprine with regard to renal relapses and HZV. At last follow-up, there were no differences in serum creatinine or proteinuria between the two groups. However, since our study lacked sufficient power, longer follow-up is needed to reveal putative differences.Kidney International (2006) 70, 732–742. doi:10.1038/sj.ki.5001630; published online 5 July 2006 [ABSTRACT FROM AUTHOR]

Background. Compared with in-center hemodialysis, self-care dialysis (including home and self-care hemodialysis and peritoneal dialysis) is less resource intensive and associated with similar clinical outcomes. However, utilization of self-care dialysis has been very low. We performed a randomized controlled trial in predialysis patients with chronic kidney disease (CKD) (GFR <30 mL/min) to determine the impact of a patient-centered educational intervention on patients' intention to initiate dialysis with self-care dialysis. Methods. Seventy patients with CKD who were receiving care in a multidisciplinary predialysis clinic were randomized to receive either ( 1) a two-phase patient-centered educational intervention (phase 1 included educational booklets and a 15-minute video on self-care dialysis; phase 2 included a 90-minute small group interactive educational session on self-care dialysis) in addition to their regular multidisciplinary care, or ( 2) ongoing standard care and education in the multidisciplinary predialysis clinic. The primary outcome was patients' intention to initiate dialysis with self-care dialysis, assessed by questionnaire. Results. Thirty-five patients were randomized to standard care; 34 completed the study. Thirty-five patients were randomized to the educational intervention; 30 completed phase 1 and 28 completed phase 2. By study end, significantly more patients in the intervention group (82.1%) intended to start dialysis with self-care dialysis compared with the standard care group (50%, P= 0.015). This difference persisted after controlling for the small baseline differences among patients in the two study groups ( P= 0.004). Conclusion. A two-phase educational intervention can increase the proportion of patients who intend to initiate dialysis with self-care dialysis. [ABSTRACT FROM AUTHOR]

Background. Hemodialysis patients are at increased risk for progressive coronary artery calcification; however, the development and progression of this disease process in patients new to hemodialysis is unknown. Method. One hundred and twenty-nine patients new to hemodialysis were randomized to receive calcium containing phosphate binders or the noncalcium phosphate binder sevelamer hydrochloride. Subjects underwent electron beam computed tomography scanning (EBCT) at entry into the study and again at 6, 12, and 18 months. Results. One hundred and nine patients underwent baseline and at least one additional assessment of coronary calcification. At baseline, 37% of sevelamer treated and 31% of calcium treated patients had no evidence of coronary calcification. No subject with a zero coronary artery calcium score (CACS) at baseline progressed to a CACS >30 over 18 months. Subjects with a CACS > 30 at baseline showed progressive increases in CACS in both treatment arms ( P < 0.05 for each time point in both groups). Subjects treated with calcium containing phosphate binders showed more rapid and more severe increases in CACS when compared with those receiving sevelamer hydrochloride ( P= 0.056 at 12 months, P= 0.01 at 18 months). Conclusion. New hemodialysis patients with no evidence of coronary calcification showed little evidence of disease development over 18 months independent of phosphate binder therapy. However, subjects with evidence of at least mild coronary calcification had significant progression at 6, 12, and 18 months. Use of calcium containing phosphate binders resulted in more rapid progression of coronary calcification than did use of sevelamer hydrochloride. [ABSTRACT FROM AUTHOR]

Biomarkers of inflammation and progression of chronic kidney disease. Background. Chronic kidney disease is associated with higher levels of inflammatory biomarkers. Statins have anti-inflammatory properties and may attenuate loss of kidney function. Although inflammation may mediate progressive renal injury, the relation between statin use, markers of inflammation, and the rate of kidney function loss has not been elucidated. We examined the association between pravastatin use, levels of C-reactive protein (CRP), soluble tumor necrosis factor receptor II (sTNFrii), and the rate of kidney function loss. Methods. We performed a post hoc analysis of data from a randomized placebo controlled trial of pravastatin 40 mg daily in people with previous myocardial infarction. Glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease Study (MDRD) GFR equation. We studied 687 subjects with chronic kidney disease (GFR< 60 mL/min/1.73 m2) who did not experience a cardiovascular event during follow-up. Multivariate linear regression was used to study the relation between baseline CRP and sTNFrii and the rate of kidney function loss in mL/min/1.73 m2/year. Cross-product interaction terms were used to determine if these relations varied with pravastatin use. Results. Median baseline GFR was 54.5 mL/min/1.73 m2 (interquartile range 49.7, 57.8) and median duration of follow-up was 58 months. Higher baseline CRP level was independently associated with more rapid kidney function loss (highest tertile 0.6 mL/min/1.73 m2 per year faster than lowest tertile) ( P= 0.001). A similar independent relation was observed between tertile of sTNFrii and rate of kidney function loss (highest tertile 0.5 mL/min/1.73 m2 per year faster than lowest tertile) ( P= 0.006). Subjects with both CRP and sTNFrii in the highest tertile (“inflamed” status) appeared to derive more renal benefit from pravastatin than those without ( P for interaction 0.047). In these 108 subjects, renal function loss in pravastatin recipients was 0.8 mL/min/1.73 m2/year slower than placebo (95% CI 0 to 1.5 mL/min/1.73 m2/year slower) ( P= 0.039). Conclusion. Higher CRP and sTNFrii are independently associated with faster rates of kidney function loss in chronic kidney disease. Pravastatin appears to prevent loss of kidney function to a greater extent in individuals with greater evidence of inflammation, although this was of borderline significance. These data suggest that inflammation may mediate the loss of kidney function among subjects with chronic kidney disease and concomitant coronary disease. [ABSTRACT FROM AUTHOR]

Background: Torsemide has predictable absorption compared to furosemide. Thereby, torsemide results in more constant exposure to active drug. Our hypothesis was that this pharmacokinetic difference between these commonly used loop diuretics may translate into disparate antihypertensive responses in patients with chronic kidney disease (CKD).Methods: We conducted a randomized, double-blind, two-period, crossover trial to compare the pharmacodynamics of torsemide and furosemide, in 14 subjects with stage 2 or 3 CKD. We first performed an inpatient study, where after the subjects were brought into sodium balance on a 200 mEq per day diet, a single bioequivalent dose of oral loop diuretic was administered with an intervening washout period. Measurements of urinary electrolytes were made. Subjects then participated in an outpatient study, wherein they received daily therapy for 3 weeks with the loop diuretics in random order. Twenty four-hour ambulatory blood pressure monitoring was performed before and after each drug to assess the antihypertensive response.Results: In the inpatient phase, furosemide increased urinary sodium excretion from average (+/-SD) 199 +/- 49 mEq/day to 357 +/- 96 mEq/day and torsemide increased urinary sodium excretion from 213 +/- 79 mEq/day to 398 +/- 142 mEq/day. These differences between the diuretics were not significant, confirming bioequivalence. In the outpatient phase, furosemide reduced 24-hour ambulatory blood pressure from 147 +/- 17/78 +/- 11 mm Hg to 138 +/- 21/74 +/- 12 mm Hg (P = 0.021) and torsemide reduced it from 143 +/- 18/75 +/- 10 mm Hg to 133 +/- 19/71 +/- 10 mm Hg (P = 0.007). Although each diuretic was effective in reducing ambulatory blood pressure, the differences between diuretics were not statistically significant.Conclusion: Bioequivalent doses of torsemide and furosemide given in a randomized, double-blind design fail to demonstrate superiority of torsemide with respect to natriuresis or 24-hour ambulatory blood pressure control in subjects with stages 2 and 3 CKD. [ABSTRACT FROM AUTHOR]

High-dose parenteral iron sucrose depresses neutrophil intracellular killing capacity. Background. Iron is essential for the formation of hemoglobin. During long-term treatment with human recombinant erythropoietin (rhEPO), the majority of end-stage renal disease (ESRD) patients will not respond adequately to rhEPO unless substituted with intravenous iron. However, concern exists about possible detrimental effects of parenteral iron on cellular host defense and iron-mediated increments of oxidative stress. Methods. We analyzed phagocytic functions of polymorphonuclear leukocytes (PMN) isolated from 20 ESRD patients on peritoneal dialysis in response to 300 mg of iron sucrose or placebo administered intravenously over two hours in a randomized, double-blind manner. We evaluated FcγR-dependent phagocytosis and killing (primary outcome variable) of opsonized Escherichia coli , FcγR-dependent oxidative burst capacity, and complement receptor 3 (CR3, Mac1, CD11b/CD18)/tumor necrosis factor alpha (TNFα)-mediated release of bactericidal lactoferrin before, during, one hour, and two days after administration. Results. The absolute count and the percentage of E. coli killed by PMN of iron sucrose–treated peritoneal dialysis patients decreased significantly over time in comparison to placebo-treated patients (F = 3.48, df = 4, P = 0.008; F = 3.99, df = 4, P = 0.006, respectively). All secondary outcome variables were not different between both groups over time. Conclusions. Killing capacity of PMN isolated from ESRD patients decreases in response to high-dose parenteral iron sucrose, possibly in part explaining reported higher hospitalization rates and lower survival rates of dialysis patients receiving frequent and high-dose parenteral iron. [ABSTRACT FROM AUTHOR]

Transferrin saturation versus reticulocyte hemoglobin content for iron deficiency in Japanese hemodialysis patients. Background. Iron deficiency is a frequent cause of recombinant human erythropoietin (rhEPO)-resistant anemia in hemodialysis patients. Both reticulocyte hemoglobin content (CHr) and transferrin saturation (TSAT) have been proposed as markers of iron deficiency, but it is unclear which parameter is superior. Methods. To compare the efficacy of CHr and TSAT as an indicator for treatment of iron deficiency, we conducted a single-center, open-label, prospective, randomized, controlled trial at the Kidney Center in Shinraku-en Hospital of 197 Japanese patients on chronic hemodialysis. After 4 weeks of run-in period during which iron supplementation was suspended, 100 patients who were randomized to the CHr group received 240 mg iron colloid intravenously over 2 weeks when CHr less than 32.5 pg, and 97 patients who were randomized to the TSAT group received the same doses of iron colloid when TSAT less than 20%. We measured the rhEPO dose needed to maintain prestudy hematocrit levels, hematocrit, CHr, TSAT, serum ferritin, percentage of hypochromic red blood cells, and total iron administered. Results. Sixteen weeks later, 94 patients in the CHr group and 89 patients in the TSAT group finished the study. The doses of rhEPO required decreased by 35.8% (4081 to 2629 U/week, P < 0.005) in the TSAT group, but not significantly in the CHr group (4121 to 3606 U/week). Although CHr increased promptly after the iron administration in both groups, TSAT increased only in the TSAT group. Conclusions. Although CHr reflects the iron status more sensitively, TSAT is a better clinical marker for iron supplementation therapy. [ABSTRACT FROM AUTHOR]