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Roxadustat (FG‐4592), an oral hypoxia‐inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis, was evaluated in a phase 1b study in patients with end‐stage renal disease with anemia on hemodialysis. Seventeen patients, on epoetin‐alfa maintenance therapy with stable hemoglobin levels ≥10 g/dL, had epoetin‐alfa discontinued on day 3 and were enrolled in this double‐blind placebo‐controlled study. Two cohorts were randomized 3:1 (roxadustat: placebo). Patients received single doses of roxadustat (1 or 2 mg/kg) or placebo 1 hour after hemodialysis on day 1 and 2 hours before dialysis on day 8. Maximum plasma concentration and area under the plasma concentration–time curve for patients receiving roxadustat were slightly more than dose proportional and elimination half‐life ranged from 14.7 to 19.4 hours. Roxadustat was highly protein bound (99%) in plasma, and dialysis contributed a small fraction of the total clearance: only 4.56% and 3.04% of roxadustat recovered from the 1 and 2 mg/kg dose groups, respectively. Roxadustat induced transient elevations of endogenous erythropoietin that peaked between 7 and 14 hours after dosing and returned to baseline by 48 hours after dosing. Peak median endogenous erythropoietin levels were 96 mIU/mL and 268 mIU/mL for the 1‐ and 2‐mg/kg doses, respectively, within physiologic range of endogenous erythropoietin responses to hypoxia at high altitude or after blood loss. No serious adverse events were reported, and there were no treatment‐ or dose‐related trends in adverse event incidence.

Background Hemodialysis patients have high rates of sudden death, but relationships between serum electrolytes, the dialysis prescription, and intra-dialytic shifts in fluid and electrolyte with arrhythmia are uncertain. Methods We analyzed sixty-six hemodialysis patients who underwent loop recorder implantation with continuous electrocardiographic monitoring, weekly to bi-weekly testing of pre- and post-dialysis electrolytes, and detailed capture of dialysis prescription and flow sheet data for 6 months. The incidence rate ratio (IRR) of reviewer confirmed arrhythmias (RCA) during dialysis through 8 h after dialysis and associations with serum chemistries and dialytic parameters were assessed using adjusted, negative-binomial regression. Results Among 66 individuals with a mean age of 56 years, 12,480 events were detected in 64 (97%) patients. RCA nadired 12–24 h after dialysis and increased during the final 12 h of the inter-dialytic interval through the first 8 h after dialysis. Higher pre-dialysis serum magnesium concentration was associated with lower incidence rate ratio for arrythmia (IRR per 1 mg/dL increase 0.49, 95% CI; 0.25, 0.94), as was dialysate calcium concentration > 2.5 mEq/L vs. 2.5 mEq/L (IRR 0.52, 95% CI: 0.39, 0.70). Neither intradialytic serum potassium nor weight change were significantly associated with RCA rate. However, there was effect modification such that arrhythmia rate was maximal with concurrently high intradialytic volume and potassium removal (Pinteraction = 0.01). Conclusions Intra and post-dialytic arrhythmias are common in hemodialysis. Additional studies designed to further elucidate whether modification of the serum magnesium concentration, dialysate calcium concentration, and the extent of intradialytic potassium and fluid removal reduces the risk of per-dialytic arrhythmia are warranted. Trial registration Clinicaltrials.gov NCT01779856. Prospectively registered on January 22, 2013. Electronic supplementary material The online version of this article (10.1186/s12882-019-1212-6) contains supplementary material, which is available to authorized users.

Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, a class of compounds that stimulate endogenous erythropoietin production.We conducted two randomized, open-label, noninferiority phase 3 trials to evaluate the safety and efficacy of vadadustat, as compared with darbepoetin alfa, in patients with anemia and incident or prevalent dialysis-dependent chronic kidney disease (DD-CKD). The primary safety end point, assessed in a time-to-event analysis, was the first occurrence of a major adverse cardiovascular event (MACE, a composite of death from any cause, a nonfatal myocardial infarction, or a nonfatal stroke), pooled across the trials (noninferiority margin, 1.25). A key secondary safety end point was the first occurrence of a MACE plus hospitalization for either heart failure or a thromboembolic event. The primary and key secondary efficacy end points were the mean change in hemoglobin from baseline to weeks 24 to 36 and from baseline to weeks 40 to 52, respectively, in each trial (noninferiority margin, -0.75 g per deciliter).A total of 3923 patients were randomly assigned in a 1:1 ratio to receive vadadustat or darbepoetin alfa: 369 in the incident DD-CKD trial and 3554 in the prevalent DD-CKD trial. In the pooled analysis, a first MACE occurred in 355 patients (18.2%) in the vadadustat group and in 377 patients (19.3%) in the darbepoetin alfa group (hazard ratio, 0.96; 95% confidence interval [CI], 0.83 to 1.11). The mean differences between the groups in the change in hemoglobin concentration were -0.31 g per deciliter (95% CI, -0.53 to -0.10) at weeks 24 to 36 and -0.07 g per deciliter (95% CI, -0.34 to 0.19) at weeks 40 to 52 in the incident DD-CKD trial and -0.17 g per deciliter (95% CI, -0.23 to -0.10) and -0.18 g per deciliter (95% CI, -0.25 to -0.12), respectively, in the prevalent DD-CKD trial. The incidence of serious adverse events in the vadadustat group was 49.7% in the incident DD-CKD trial and 55.0% in the prevalent DD-CKD trial, and the incidences in the darbepoetin alfa group were 56.5% and 58.3%, respectively.Among patients with anemia and CKD who were undergoing dialysis, vadadustat was noninferior to darbepoetin alfa with respect to cardiovascular safety and correction and maintenance of hemoglobin concentrations. (Funded by Akebia Therapeutics and Otsuka Pharmaceutical; INNO

Sudden death is one of the more frequent causes of death for hemodialysis patients, but the underlying mechanisms, contribution of arrhythmia, and associations with serum chemistries or the dialysis procedure are incompletely understood. To study this, implantable loop recorders were utilized for continuous cardiac rhythm monitoring to detect clinically significant arrhythmias including sustained ventricular tachycardia, bradycardia, asystole, or symptomatic arrhythmias in hemodialysis patients over six months. Serum chemistries were tested pre- and post-dialysis at least weekly. Dialysis procedure data were collected at every session. Associations with clinically significant arrhythmias were assessed using negative binomial regression modeling. Sixty-six patients were implanted and 1678 events were recorded in 44 patients. The majority were bradycardias (1461), with 14 episodes of asystole and only one of sustained ventricular tachycardia. Atrial fibrillation, although not defined as clinically significant arrhythmias, was detected in 41% of patients. With thrice-weekly dialysis, the rate was highest during the first dialysis session of the week and was increased during the last 12 hours of each inter-dialytic interval, particularly the long interval. Among serum and dialytic parameters, only higher pre-dialysis serum sodium and dialysate calcium over 2.5 mEq/L were independently associated with clinically significant arrhythmias. Thus, clinically significant arrhythmias are common in hemodialysis patients, and bradycardia and asystole rather than ventricular tachycardia may be key causes of sudden death in hemodialysis patients. Associations with the temporal pattern of dialysis suggest that modification of current dialysis practices could reduce the incidence of sudden death.

Background Inflammation signaled by Janus kinases (JAKs) promotes progression of diabetic kidney disease (DKD). Baricitinib is an oral, reversible, selective inhibitor of JAK1 and JAK2. This study tested the efficacy of baricitinib versus placebo on albuminuria in adults with Type 2 diabetes at high risk for progressive DKD. Methods In this Phase 2, double-blind, dose-ranging study, participants were randomized 1:1:1:1:1 to receive placebo or baricitinib (0.75 mg daily; 0.75 mg twice daily; 1.5 mg daily; or 4 mg daily), for 24 weeks followed by 4–8 weeks of washout. Results Participants (N = 129) were 63±9.1 (mean±standard deviation) years of age, 27.1% (35/129) women and 11.6% (15/129) African-American race. Baseline hemoglobin A1c (HbA1c) was 7.3±1% and estimated glomerular filtration rate was 45.0±12.1 mL/min/1.73 m2 with first morning urine albumin–creatinine ratio (UACR) of 820 (407–1632) (median; interquartile range) mg/g. Baricitinib, 4 mg daily, decreased morning UACR by 41% at Week 24 compared with placebo (ratio to baseline 0.59, 95% confidence interval 0.38–0.93, P = 0.022). UACR was decreased at Weeks 12 and 24 and after 4–8 weeks of washout. Baricitinib 4 mg decreased inflammatory biomarkers over 24 weeks (urine C–X–C motif chemokine 10 and urine C–C motif ligand 2, plasma soluble tumor necrosis factor receptors 1 and 2, intercellular adhesion molecule 1 and serum amyloid A). The only adverse event rate that differed between groups was anemia at 32.0% (8/25) for baricitinib 4 mg daily versus 3.7% (1/27) for placebo. Conclusions Baricitinib decreased albuminuria in participants with Type 2 diabetes and DKD. Further research is required to determine if baricitinib reduces DKD progression.

IgA nephropathy frequently leads to progressive CKD. Although interest surrounds use of immunosuppressive agents added to standard therapy, several recent studies have questioned efficacy of these agents. Depleting antibody–producing B cells potentially offers a new therapy. In this open label, multicenter study conducted over 1-year follow-up, we randomized 34 adult patients with biopsy–proven IgA nephropathy and proteinuria >1 g/d, maintained on angiotensin–converting enzyme inhibitors or angiotensin receptor blockers with well controlled BP and eGFR

Background Dialysis patients have high rates of cardiovascular morbidity and mortality, but data on arrhythmia burden, arrhythmia type, arrhythmia triggers, and the identity of terminal arrhythmias have historically been limited by an inability to monitor heart rhythm for prolonged periods. Objectives To investigate arrhythmia and its association with sudden death in dialysis-dependent ESRD, describe the potential for implantable devices to advance study of dialysis physiology, review the ethical implications of using implantable devices in clinical studies, and report on the protocol and baseline results of the Monitoring in Dialysis Study (MiD). Design, setting, participants, & measurements In this multicenter, interventional-observational, prospective cohort study, we placed implantable loop recorders in patients undergoing long-term hemodialysis. The proportion of patients experiencing clinically significant arrhythmias was the primary endpoint. For 6 months, we captured detailed data on the primary endpoint, symptomatic arrhythmias, other electrocardiographic variables, dialysis prescription, electrolytes, dialysis-related variables, and vital signs. We collected additional electrocardiographic data for up to 1 year. Results Overall, 66 patients underwent implantation in sites in the United States and India. Diabetes was present in 63.6% of patients, 12.1% were age ≥70 years, 69.7% were men, and 53.0% were black. Primary and secondary endpoint data are expected in 2016. Conclusions Cardiac arrhythmia is an important contributor to cardiovascular morbidity and mortality in dialysis patients, but available technology has previously limited the ability to estimate its true burden and triggers and to define terminal rhythms in sudden death. Use of implantable technology in observational studies raises complex issues but may greatly expand understanding of dialysis physiology. The use of implantable loop recorders in MiD is among the first examples of such a trial, and the results are expected to provide novel insights into the nature of arrhythmia in hemodialysis patients.

Calcineurin inhibitors added to standard-of-care induction therapy for lupus nephritis (LN) may increase complete renal remission (CRR) rates. The AURA-LV study tested the novel calcineurin inhibitor voclosporin for efficacy and safety in active LN. AURA-LV was a Phase 2, multicenter, randomized, double-blind, placebo-controlled trial of two doses of voclosporin (23.7 mg or 39.5 mg, each twice daily) versus placebo in combination with mycophenolate mofetil (2 g/d) and rapidly tapered low-dose oral corticosteroids for induction of remission in LN. The primary endpoint was CRR at 24 weeks; the secondary endpoint was CRR at 48 weeks. Two hundred sixty-five subjects from 79 centers in 20 countries were recruited and randomized to treatment for 48 weeks. CRR at week 24 was achieved by 29 (32.6%) subjects in the low-dose voclosporin group, 24 (27.3%) subjects in the high-dose voclosporin group, and 17 (19.3%) subjects in the placebo group (OR=2.03 for low-dose voclosporin versus placebo). The significantly greater CRR rate in the low-dose voclosporin group persisted at 48 weeks, and CRRs were also significantly more common in the high-dose voclosporin group compared to placebo at 48 weeks. There were more serious adverse events in both voclosporin groups, and more deaths in the low-dose group compared to placebo and high-dose voclosporin groups (11.2%, 1.1%, and 2.3%, respectively). These results suggest that the addition of low-dose voclosporin to mycophenolate mofetil and corticosteroids for induction therapy of active LN results in a superior renal response compared to mycophenolate mofetil and corticosteroids alone, but higher rates of adverse events including death were observed.

BACKGROUND Vasodilatory shock that does not respond to high-dose vasopressors is associated with high mortality. We investigated the effectiveness of angiotensin II for the treatment of patients with this condition. METHODS We randomly assigned patients with vasodilatory shock who were receiving more than 0.2 mu g of norepinephrine per kilogram of body weight per minute or the equivalent dose of another vasopressor to receive infusions of either angiotensin II or placebo. The primary end point was a response with respect to mean arterial pressure at hour 3 after the start of infusion, with response defined as an increase from baseline of at least 10 mm Hg or an increase to at least 75 mm Hg, without an increase in the dose of background vasopressors. RESULTS A total of 344 patients were assigned to one of the two regimens; 321 received a study intervention (163 received angiotensin II, and 158 received placebo) and were included in the analysis. The primary end point was reached by more patients in the angiotensin II group (114 of 163 patients, 69.9%) than in the placebo group (37 of 158 patients, 23.4%) (odds ratio, 7.95; 95% confidence interval [CI], 4.76 to 13.3; P

Summary Background Prognostic biomarkers that predict the severity of AKI at an early time point are needed. Urinary angiotensinogen was recently identified as a prognostic AKI biomarker. The study hypothesis is that urinary renin could also predict AKI severity and that in combination angiotensinogen and renin would be a strong predictor of prognosis at the time of AKI diagnosis. Design, setting, participants, & measurements In this multicenter, retrospective cohort study, urine was obtained from 204 patients who developed AKI after cardiac surgery from August 2008 to June 1, 2012. All patients were classified as having Acute Kidney Injury Network (AKIN) stage 1 disease by serum creatinine criteria at the time of sample collection. Urine output was not used for staging. Urinary angiotensinogen and renin were measured, and the area under the receiver-operating characteristic curve (AUC) was used to test for prediction of progression to AKIN stage 3 or in-hospital 30-day mortality. These biomarkers were added stepwise to a clinical model, and improvement in prognostic predictive performance was evaluated by category free net reclassification improvement (cfNRI) and chi-squared automatic interaction detection (CHAID). Results Both the urinary angiotensinogen-to-creatinine ratio (uAnCR; AUC, 0.75; 95% confidence interval [CI], 0.65 to 0.85) and the urinary renin-to-creatinine ratio (uRenCR; AUC, 0.70; 95% CI, 0.57 to 0.83) predicted AKIN stage 3 or death. Addition of uAnCR to a clinical model substantially improved prediction of the outcome (AUC, 0.85; cfNRI, 0.673), augmenting sensitivity and specificity. Further addition of uRenCR increased the sensitivity of the model (cfNRIevents, 0.44). CHAID produced a highly accurate model (AUC, 0.91) and identified the combination of uAnCR >337.89 ng/mg and uRenCR >893.41 pg/mg as the strongest predictors (positive predictive value, 80.4%; negative predictive value, 90.7%; accuracy, 90.2%). Conclusion The combination of urinary angiotensinogen and renin predicts progression to very severe disease in patients with early AKI after cardiac surgery.

Summary Background and objectives A dose-finding study was undertaken to investigate the efficacy of PA21, a novel polynuclear iron(III)-oxyhydroxide phosphate binder. Design, setting, participants, & measurements In a randomized, active-controlled, multicenter, open-label study at 50 clinical sites in Europe and the United States, hemodialysis patients were randomized to PA21 at dosages of 1.25, 5.0, 7.5, 10.0, or 12.5 g/d or sevelamer-HCl 4.8 g/d for 6 weeks. The primary efficacy endpoint was the change in serum phosphorus concentration from baseline. Results There were 154 participants who were randomized and received the study drug. All groups except PA21 1.25 g/d showed a significant decrease in serum phosphorus. Mean decreases in serum phosphorus in PA21 10 g/d and 12.5 g/d were −2.00±1.71 mg/dl and −1.69±1.81 mg/dl, respectively. A similar decrease to sevelamer-HCl (−1.06±1.35 mg/dl) was seen with PA21 5.0 g/d (−1.08±2.12 mg/dl) and 7.5 g/d (−1.25±1.21 mg/d). Overall, 60.9% of participants randomized to PA21 and 57.7% randomized to sevelamer-HCl reported ≥1 adverse event. The most frequent adverse events were hypophosphatemia (18.0%) and discolored feces (11.7%) for the pooled PA21 dose groups, and diarrhea, hypophosphatemia, and hypotension (each 11.5%) for sevelamer-HCl. Discontinuation due to adverse events occurred at a similar rate in PA21-treated (21.1%) and sevelamer-HCl–treated (23.1%) participants. Conclusions PA21 5–12.5 g/d significantly reduces serum phosphorus in hemodialysis patients. The 5 g/d and 7.5 g/d dosages showed similar efficacy to 4.8 g/d of sevelamer-HCl. The adverse events rate was similar for PA21 and sevelamer-HCl.

Summary Background Biomarkers of AKI that can predict which patients will develop severe renal disease at the time of diagnosis will facilitate timely intervention in populations at risk of adverse outcomes. Design, setting, participants, & measurements Liquid chromatography/tandem mass spectrometry was used to identify 30 potential prognostic urinary biomarkers of severe AKI in a group of patients that developed AKI after cardiac surgery. Angiotensinogen had the best discriminative characteristics. Urinary angiotensinogen was subsequently measured by ELISA and its prognostic predictive power was verified in 97 patients who underwent cardiac surgery between August 1, 2008 and October 6, 2011. Results The urine angiotensinogen/creatinine ratio (uAnCR) predicted worsening of AKI, Acute Kidney Injury Network (AKIN) stage 3, need for renal replacement therapy, discharge >7 days from sample collection, and composite outcomes of AKIN stage 2 or 3, AKIN stage 3 or death, and renal replacement therapy or death. The prognostic predictive power of uAnCR was improved when only patients classified as AKIN stage 1 at the time of urine sample collection (n=79) were used in the analysis, among whom it predicted development of stage 3 AKI or death with an area under the curve of 0.81. Finally, category free net reclassification improvement showed that the addition of uAnCR to a clinical model to predict worsening of AKI improved the predictive power. Conclusions Elevated uAnCR is associated with adverse outcomes in patients with AKI. These data are the first to demonstrate the utility of angiotensinogen as a prognostic biomarker of AKI after cardiac surgery.

Since 2012, a number of case reports have described the occurrence of thrombotic microangiopathy (TMA) following IV abuse of extended-release oxymorphone hydrochloride (Opana ER), an oral opioid for long-term treatment of chronic pain. Here, we present unique clinical features of 3 patients and investigate IV exposure to the tablet’s inert ingredients as a possible causal mechanism. Guinea pigs were used as an animal model to understand the hematopathologic and nephrotoxic potential of the inert ingredient mixture (termed here as PEO+) which primarily contains high-molecular-weight polyethylene oxide (HMW PEO). Microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury were found in a group of 3 patients following recent injection of adulterated extended-release oxymorphone tablets. Varying degrees of cardiac involvement and retinal ischemia occurred, with TMA evident on kidney biopsy. A TMA-like state also developed in guinea pigs IV administered PEO+. Acute tubular and glomerular renal injury was accompanied by nonheme iron deposition and hypoxia-inducible factor-1α upregulation in the renal cortex. Similar outcomes were observed following dosing with HMW PEO alone. IV exposure to the inert ingredients in reformulated extended-release oxymorphone can elicit TMA. Although prescription opioid abuse shows geographic variation, all physicians should be highly inquisitive of IV drug abuse when presented with cases of TMA.

The addition of calcineurin inhibitors, including cyclosporine A (CsA) and FK-506 (tacrolimus), to transplant protocols has markedly reduced acute allograft rejection and prolonged patient survival. Although monitoring of serum drug levels has been shown to be a poor indicator of efficacy, there is little data on calcineurin enzymatic activity in humans. Therefore, we measured calcineurin in isolated CD3(+)/4(+) T cells from 81 non-transplant controls and 39 renal allograft patients by using a (32)PO(4)-labeled calcineurin-specific substrate. A gender difference was observed in the control cohort, with activity in males significantly higher than that in females (1073 +/- 134 versus 758 +/- 75 fmol/microg/min, respectively). Activity of both groups was comparably inhibited by 5 ng/ml tacrolimus (27 +/- 4 versus 30 +/- 4%). Calcineurin is a downstream target of the T-cell receptor (TCR). Therefore, activity was measured in isolated T cells after incubation with anti-CD3/CD28 antibodies to stimulate the TCR. Calcineurin activity increased significantly from 1214 +/- 111 to 1652 +/- 138 fmol/microg/min; addition of either tacrolimus or CsA (500 ng/ml) blocked CD3/CD28 stimulation. Despite therapeutic levels of tacrolimus and CsA (mean 11.4 and 172 ng/ml), basal calcineurin activity was significantly higher among renal transplant recipients than controls (1776 +/- 175 versus 914 +/- 78 fmol/microg/min). In contrast, anti-CD3/CD28 antibodies failed to stimulate calcineurin activity in transplant subjects. Finally, we found that basal and stimulated calcineurin activities are inversely related. Consistent with this finding, basal activity in resting T cells rose over time after transplant but stimulation fell (r(2) = 0.785, p0.05). These data suggest that examination of TCR-stimulated calcineurin activity after renal transplantation may be useful for monitoring immunosuppression of individual patients.

Objective To investigate whether treatment with abetimus delays renal flare in patients with lupus nephritis. Secondary objectives included evaluation of the effect of abetimus on C3 levels, anti–double-stranded DNA (anti-dsDNA) antibody levels, use of high-dose corticosteroids and/or cyclophosphamide, and major systemic lupus erythematosus (SLE) flare. Methods We conducted a randomized, placebo-controlled study of treatment with abetimus at 100 mg/week for up to 22 months in SLE patients. Three hundred seventeen patients with a history of renal flare and anti-dsDNA levels >15 IU/ml were randomized to a treatment group (158 abetimus, 159 placebo); 298 (94%) were enrolled in the intent-to-treat (ITT) population (145 abetimus, 153 placebo), based on the presence of high-affinity antibodies for the oligonucleotide epitope of abetimus at baseline screening. Results Abetimus did not significantly prolong time to renal flare, time to initiation of high-dose corticosteroid and/or cyclophosphamide treatment, or time to major SLE flare. However, there were 25% fewer renal flares in the abetimus group compared with the placebo group (17 of 145 abetimus-treated patients [12%] versus 24 of 153 placebo-treated patients [16%]). Abetimus treatment decreased anti-dsDNA antibody levels (P < 0.0001), and reductions in anti-dsDNA levels were associated with increases in C3 levels (P < 0.0001). More patients in the abetimus group experienced ≥50% reductions in proteinuria at 1 year, compared with the placebo group (nominal P = 0.047). Trends toward reduced rates of renal flare and major SLE flare were noted in patients treated with abetimus who had impaired renal function at baseline. Treatment with abetimus for up to 22 months was well tolerated. Conclusion Abetimus at 100 mg/week significantly reduced anti-dsDNA antibody levels but did not significantly prolong time to renal flare when compared with placebo. Multiple positive trends in renal end points were observed in the abetimus treatment group.

Calcineurin inhibitors are effective therapy for steroid-resistant focal segmental glomerulosclerosis (FSGS) but are associated with significant morbidity and nephrotoxicity. Sirolimus is a novel immunosuppressive agent that is structurally related to tacrolimus but demonstrates no long-term nephrotoxicity. For determination of the efficacy of sirolimus in reducing proteinuria, a prospective, open-label trial was conducted of 21 patients with idiopathic, steroid-resistant FSGS. A complete response was defined as300 mg protein/24 h after 6 mo, whereas a partial response was defined as a 50% reduction in baseline proteinuria. After 6 mo of therapy, sirolimus induced complete remission in four (19%) of 21 patients and partial remissions in eight (38%). Among sirolimus-responsive patients, 6 mo of therapy decreased proteinuria from a mean of 8.8 +/- 1.7 to 2.1 +/- 0.5 g/24 h (P = 0.0003). In responsive patients, GFR was maintained (45 +/- 6 versus 47 +/- 7 ml/min per 1.73 m2 at 6 mo) throughout the study, whereas nonresponders tended to decrease (31 +/- 4 versus 28 +/- 5 ml/min per 1.73 m2). Using dextran sieving analysis, complete or partial response was associated with an increase in the glomerular ultrafiltration coefficient (K(f), 7 +/- 1. versus 8 +/- 0.9 units at 6 mo; P0.05). Glomerular permselectivity and K(f) tended to decrease in nonresponders (8.2 +/- 1.9 versus 6.2 +/- 1.3 units at 6 mo; P = 0.07). Patients with complete remission had a higher GFR (45 +/- 6 versus 31 +/- 4 ml/min per 1.73 m2) at the end of 6 mo compared with nonresponders. In patients with steroid-resistant FSGS, sirolimus reduced proteinuria and glomerular pore size and increased K(f) in patients with steroid-resistant FSGS.

Background: Acute tubular necrosis (ATN) occurs commonly in critically ill patients and is associated with increased morbidity and mortality. Fenoldopam is a dopamine receptor α1-specific agonist that increases renal blood flow in patients with kidney failure. We hypothesized that administration of low-dose fenoldopam during early ATN would decrease the need for dialysis therapy and/or incidence of death at 21 days. Methods: We conducted a prospective, randomized, double-blind, placebo-controlled, clinical trial in 155 patients with early ATN. Patients were considered eligible for enrollment if serum creatinine level increased to 50% greater than admission levels within 24 hours and mean arterial pressure was greater than 70 mm Hg. Patients were randomly assigned to the administration of placebo or fenoldopam for 72 hours. Results: Overall, 22 of 80 patients (27.5%) in the fenoldopam group reached the primary end point compared with 29 of 75 patients (38.7%) in the placebo group (P = 0.235). This 11% absolute reduction in the primary end point was not statistically significant (P = 0.23). Similarly, there was no difference in the incidence of dialysis therapy between patients randomly assigned to fenoldopam (13 of 80 patients; 16.25%) versus the placebo group (19 of 75 patients; 25.3%; P = 0.163). Moreover, there was no statistically significant difference in 21-day mortality rates between the 2 groups (fenoldopam, 13.8% versus placebo, 25.3%; P = 0.068). In secondary analyses, fenoldopam tended to reduce the primary end point in patients without diabetes and postoperative cardiothoracic surgery patients with early ATN (fenoldopam patients without diabetes, 14 of 54 patients [25.9%] versus placebo patients without diabetes, 23 of 52 patients [44.2%]; P = 0.048) and postoperative cardiothoracic patients (6 of 34 patients [17.6%] versus 14 of 36 patients [38.8%]; P = 0.049). Conversely, fenoldopam did not improve the primary end point in patients with diabetes or those with acute renal failure from other causes. A larger multicenter trial using separate randomizations for patients with and without diabetes will be needed to determine the efficacy of fenoldopam mesylate in specific subpopulations with ATN. Conclusion: Fenoldopam does not reduce the incidence of death or dialysis therapy in intensive care unit patients with early ATN.

Background. IgA nephropathy is an immune-complex glomerulopathy that can result in capillary or extracapillary proliferation. Previous attempts to correlate specific histological findings including cellular crescents or endocapillary proliferation, with clinical outcomes, have produced conflicting results. Methods. We conducted a prospective open-labelled trial of 12 patients with crescentic, proliferative IgA nephropathy and clinically progressive disease and treated them with pulse steroids and intravenous cyclophosphamide. Therapy included pulse solumedrol at 15 mg/kg/day for 3 days, followed by monthly intravenous cyclophosphamide at 0.5 g/m 2 body surface area for 6 months. Clinically significant proteinuria (> 1.0 g/24 h) was present in all patients, while nephrotic-range proteinuria (>3.0 g/24 h) was observed in eight of 12 patients. All patients were hypertensive (BP > 140 90 mmHg). Results. After 6 months of treatment, the mean serum creatinine was reduced from a maximum of 2.65 ±0.39 to 1.51±0.10 mg/dl (P

Background Radiocontrast nephropathy (RCN) is a common source of acute renal failure in hospitalized patients and is associated with increased morbidity and mortality rates. Fenoldopam mesylate is a dopamine A1 receptor agonist that augments renal plasma flow (RPF) in patients with normotensive and hypertensive conditions. To determine whether fenoldopam mesylate attenuates reductions in RPF after contrast infusion, we conducted a double-blind, randomized, placebo-controlled pilot trial of fenoldopam mesylate in patients who underwent contrast angiography. Methods Fifty-one patients with chronic renal insufficiency (creatinine level, 2.0-5.0 mg/dL) who were undergoing contrast angiography were screened, and 45 patients were randomized to receive normal saline solution (1/2 NS) or 1/2 NS plus fenoldopam mesylate at 0.1 μg/kg/min at lease 1 hour before infusion with contrast dye. Serum creatinine level was measured at baseline and at 24, 48, and 72 hours after angiography. The primary endpoint was change in RPF 1 hour after contrast infusion. The secondary endpoint was incidence of RCN, defined as a 0.5 mg/dL or a 25% rise in serum creatinine level at 48 hours. Results RPF at 1 hour after angiography was 15.8% above baseline in the fenoldopam mesylate group compared with 33.2% below baseline in the 1/2 NS group (P

Background and Objective.Adrenocorticotropic hormone (ACTH) is able to reduce proteinuria in nondiabetic glomerulopathies through activation of melanocortin receptors (MCR) expressed in the podocyte. To determine the efficacy of ACTH, we conducted a randomized, open-label pilot trial of ACTH gel in patients with advanced diabetic nephropathy.Study Design.Twenty-three (23) patients with diabetic nephropathy were randomized to daily subcutaneous (SQ) injections of 16 or 32 units of ACTH gel for six months.Outcome.The primary endpoint was the percentage of patients achieving a complete remission (Results.After 6 months of ACTH gel therapy, 8 of 14 (57%) patients achieved a complete (n=1) or partial (n=7) remission. In the low-dose ACTH gel group (16 units), urinary protein fell from6709+953to2224+489 mg/24 hrs (P<0.001). In contrast, 2 of 6 patients in the 32-unit group achieved partial remission, but aggregate proteinuria (5324+751to5154+853 mg/24 hours) did not change. Urinary VEGF increased from 388 to 1346 pg/mg urinary creatinine (P<0.02) in the low-dose group but remained unchanged in the high-dose group.Conclusion.ACTH gel stabilizes renal function and reduces urinary protein for up to 6 months after treatment. The ClinTrials.gov identifier isNCT01028287.

Biomarkers for acute kidney injury (AKI) have been used to predict the progression of AKI, but a systematic comparison of the prognostic ability of each biomarker alone or in combination has not been performed. In order to assess this, we measured the concentration of 32 candidate biomarkers in the urine of 95 patients with AKIN stage 1 after cardiac surgery. Urine markers were divided into eight groups based on the putative pathophysiological mechanism they reflect. We then compared the ability of the markers alone or in combination to predict the primary outcome of worsening AKI or death (23 patients) and the secondary outcome of AKIN stage 3 or death (13 patients). IL-18 was the best predictor of both outcomes (AUC of 0.74 and 0.89). L-FABP (AUC of 0.67 and 0.85), NGAL (AUC of 0.72 and 0.83), and KIM-1 (AUC of 0.73 and 0.81) were also good predictors. Correlation between most of the markers was generally related to their predictive ability, but KIM-1 had a relatively weak correlation with other markers. The combination of IL-18 and KIM-1 had a very good predictive value with an AUC of 0.93 to predict AKIN 3 or death. Thus, a combination of IL-18 and KIM-1 would result in improved identification of high-risk patients for enrollment in clinical trials.

Acute kidney injury (AKI) is characterized by deterioration in kidney function resulting in multisystem abnormalities. Much of the morbidity and mortality associated with AKI result from a systemic inflammatory response syndrome (SIRS). This study described herein is a prospective, single-arm, multicenter US study designed to evaluate the safety and efficacy of the Selective Cytopheretic Device (SCD) treatment on AKI requiring continuous renal replacement therapy (CRRT) in the ICU. The study enrolled 35 subjects. The mean age was 56.3±15. With regard to race, 71.4% of the subjects were Caucasian, 22.9% were Black, and 5.7% were Hispanic. Average SOFA score was 11.3±3.6. Death from any cause at Day 60 was 31.4%. Renal recovery, defined as dialysis independence, was observed in all of the surviving subjects at Day 60. The results of this pilot study indicate the potential for a substantial improvement in patient outcomes over standard of care therapy, which is associated with a greater than 50% 60-day mortality in the literature. The SCD warrants further study in scientifically sound, pivotal trial to demonstrate reasonable assurance of safety and effectiveness.

We reported that feeding rats 8% protein for 3 wk induces net urea transport and morphologic changes in initial inner medullary collecting ducts (IMCDs) which are not present in rats fed 18% protein. In this study, we measured net urea transport in microperfused initial IMCDs from rats fed 8% protein for > or = 3 wk and tested the effect of inhibiting Na+/K(+)-ATPase activity and found that adding 1 mM ouabain to the bath reversibly inhibited net urea transport from 14 +/- 3 to 6 +/- 2 pmol/mm per min (P < 0.01), and that replacing potassium (with sodium) in the bath reversibly inhibited net urea transport from 18 +/- 3 to 5 +/- 0 pmol/mm per min (P < 0.01). Replacing perfusate sodium with N-methyl-D-glucamine reversibly inhibited net urea transport from 12 +/- 2 to 0 +/- 1 pmol/mm per min (P < 0.01), whereas replacing bath sodium had no significant effect on net urea transport. Adding 10 nM vasopressin to the bath exerted no significant effect on net urea transport. Finally, we measured Na+/K(+)-ATPase activity in initial and terminal IMCDs from rats fed 18% or 8% protein and found no significant difference in either subsegment. Thus, net urea transport in initial IMCDs from rats fed 8% protein for > or = 3 wk requires sodium in the lumen, is reduced by inhibiting Na+/K(+)-ATPase, and is unchanged by vasopressin or phloretin. These results suggest that net urea transport may occur via a novel, secondary active, sodium-urea cotransporter.

Despite increasing attention to the long-term risks of radiation exposure and contrast-induced nephropathy (CIN), institutional guidelines and patient consent procedures for contrast-enhanced computed tomography (CECT) imaging in the emergency department (ED) setting have focused primarily on more immediate complications, directly attributable to the administration of intravenous (IV) iodinated contrast administration. Thus, this study sought to define the risk of these immediate complications with the overall aim of improving institutional guidelines and patient consent procedures.This was a prospective, consecutive cohort study of patients undergoing CECT of any body region in the ED, for complications occurring within 1 week of contrast administration, using predefined implicit definitions. Severe complications were defined as any of the following requiring medical or surgical intervention: bronchospasm with acute respiratory failure, airway obstruction, anaphylactoid shock, or acute pulmonary edema. The development of compartment syndrome, lactic acidosis, or pulmonary edema within 1 week of contrast administration was also considered a severe complication.Of 633 patients, only five (0.8%, 95% confidence interval [CI] = 0.3% to 1.8%) reported any immediate complications, all of which were classified as minor. No patient developed a reaction meeting the study definition of a severe complication.The frequency of severe, immediate complications from CECT imaging that includes IV contrast is less than 1%, and the frequency of mild complications is less than 2%. The authors conclude that CECT is associated with a very low rate of severe immediate complications.

Purpose: A synthetic adrenocorticotropin (ACTH) analog has shown efficacy in Europe as primary and secondary therapy for nephrotic syndrome, but there is no published experience using the natural, highly purified ACTH gel formulation, available in the United States, for nephrotic syndrome. We therefore investigated the use of ACTH gel for nephrotic syndrome in the United States. Patients and methods: Twenty-one patients with nephrotic syndrome treated with ACTH gel outside of research settings in the United States, with initiation of therapy by December 31, 2009, allowing a minimum 6 months follow-up. We defined complete remission as stable renal function with proteinuria falling to 50% reduction in proteinuria from 500 to 3500 mg/day. Results: Twenty-one patients with nephrotic syndrome were treated: 11 with idiopathic membranous nephropathy (iMN), 4 with membranoproliferative glomerulonephritis (MPGN), 1 with focal segmental glomerulosclerosis (FSGS), 1 with minimal change disease (MCD), 1 with immunoglobulin A (IgA) nephropathy, 1 with class V systemic lupus erythematosus (SLE) glomerulonephritis, 1 with monoclonal diffuse proliferative glomerulonephritis, and 1 with unbiopsied nephrotic syndrome. ACTH was used as primary therapy for 3 patients; the remaining patients had previously failed a mean 2.3 immunosuppressive regimens. Eleven patients achieved a complete or partial remission, with 4 (19%) in complete remission. Of the 11 patients who achieved remission, 9 had iMN, 1 had FSGS, and 1 had IgA nephropathy. Of the 11 patients with iMN, 3 (27%) achieved complete remission and 6 (55%) achieved partial remission despite having previously failed a mean 2.4 therapies. Five patients reported steroid-like adverse effects, but there were no severe infections. The limitations were retrospective data analysis with short-term follow-up. Conclusion: ACTH gel may be a viable treatment option for resistant nephrotic syndrome due to membranous nephropathy. Short-term data suggest that remission rates may approach 80%.

Nephron segment-specific inhibition of Na+/K+-ATPase activity by cyclosporin A. Decreased kaliuresis and hyperkalemia are common complications of cyclosporin A (CsA) therapy. If CsA significantly inhibits renal tubular Na+/K+-ATPase activity, the alteration in transepithelial K+ secretion and K+ homeostasis could result in hyperkalemia. To investigate this possibility, we tested the effects of CsA on Na+/K+-ATPase activity in microdissected rat tubules. CsA, at a “toxic” concentration of 600 ng/ml, significantly inhibited Na+/K+-ATPase in cortical collecting ducts (CCD), medullary thick ascending limbs (mTAL), and outer medullary collecting ducts from the outer stripe (OMCDos) by 35%, 53%, and 39%, respectively. Cremophore, the commercial vehicle for CsA, did not change Na+/K+-ATPase activity in any nephron segment tested. To determine whether CsA inhibits Na+/K+-ATPase activity in a dose-dependent manner, microdissected CCD's were incubated with 300, 600, and 2500 ng/ml of CsA for 30 minutes. Na+/K+-ATPase activity was inhibited at 600 and 2500 ng/ml, but not at 300 ng/ml. No further inhibition of enzyme activity was noted at 2500 ng/ml. CsA did not change Na+/K+-ATPase activity in proximal tubule S1, S2, and S3 subsegments; cortical thick ascending limbs (cTAL), connecting tubules (CNT), or outer medullary collecting ducts from the inner stripe (OMCDis). Prolonging the incubation of CsA with S2 subsegments to 60 minutes did not result in inhibition of Na+/K+-ATPase activity. Ouabain-insensitive ATPase activity was unaffected by CsA or its vehicle in any nephron segment tested. In summary, CsA specifically inhibits Na+/K+-ATPase activity in the CCD, mTAL, and OMCDos. In the CCD, inhibition of Na+/K+-ATPase activity was dose-dependent and occurred at concentrations commonly associated with clinical CsA toxicity (600 to 2500 ng/ml). CsA-induced inhibition of Na+/K+-ATPase activity in the CCD and OMCDos could decrease K+ secretion and contribute to clinical hyperkalemia.

Background and objectives: Although uremic pruritus (UP) is a highly prevalent complication of chronic kidney disease, it remains poorly characterized. There have been no longitudinal studies of natural history, and no health-related quality of life (HR-QOL) instruments have been developed for UP. The objectives of this study were to describe the natural history of UP, to compare rating scales of itching intensity, and to assess usefulness and validity of HR-QOL instruments for UP. Design, setting, participants, & measurements: The intensity, severity, and effects of pathologic itching on HR-QOL were assessed prospectively in 103 patients with UP on chronic hemodialysis. Outcome measures were obtained at scheduled intervals over 3.5 months. Results: Itching daily or nearly daily was reported by 84% of patients and had been ongoing for >1 year in 59%. In 83%, pruritus involved large, nondermatomal areas with striking bilateral symmetry. Two thirds of the patients were using medications such as antihistamines, steroids, and various emollients without satisfactory relief of itching. Statistically significant associations were found among itching intensity, severity, and HR-QOL measures in domains such as mood, social relations, and sleep. Among patients with moderate-to-severe UP, changes in itching intensity of 20% or greater were associated with significant reductions in HR-QOL measures. Conclusions: This first longitudinal study of UP describes key features of UP and its effect on HR-QOL. The assessment instruments we have developed are easily used, are responsive to changes in UP intensity, and should facilitate clinical evaluation and research to meet the needs of afflicted patients.

Despite widespread use of tunneled hemodialysis (HD) catheters, their utility is limited by the development of thrombotic complications. To address this problem, this study investigated whether the thrombolytic agent tenecteplase can restore blood flow rates (BFRs) in dysfunctional HD catheters.In this randomized, double-blind study, patients with dysfunctional tunneled HD catheters, defined as a BFR300 ml/min at -250 mmHg pressure in the arterial line, received 1-hour intracatheter dwell with tenecteplase (2 mg) or placebo. The primary endpoint was the percentage of patients with BFRor =300 ml/min and an increase ofor =25 ml/min above baseline 30 minutes before and at the end of HD. Safety endpoints included the incidence of hemorrhagic, thrombotic, and infectious complications.Eligible patients (n = 149) were treated with tenecteplase (n = 74) or placebo (n = 75). Mean baseline BFR was similar for the tenecteplase and placebo groups at 151 and 137 ml/min, respectively. After a 1-hour dwell, 22% of patients in the tenecteplase group had functional catheters compared with 5% among placebo controls (P = 0.004). At the end of dialysis, mean change in BFR was 47 ml/min in the tenecteplase group versus 12 ml/min in the placebo group (P = 0.008). Four catheter-related bloodstream infections (one tenecteplase, three placebo) and one thrombosis (tenecteplase) were observed. There were no reports of intracranial hemorrhage, major bleeding, embolic events, or catheter-related complications.Tenecteplase improved HD catheter function and had a favorable safety profile compared with placebo.

Background and objectives: No prospective study has reported the incidence of contrast-induced nephropathy (CIN) or the associated morbidity and mortality after contrast-enhanced computed tomography (CECT) in the outpatient setting. Design, setting, participants, & measurements: We enrolled and followed a prospective, consecutive cohort (June 2007 through January 2009) of patients who received intravenous contrast for CECT in the emergency department of a large, academic, tertiary care center. Outcomes measured were as follows (1) CIN: An increase in serum creatinine ≥0.5 mg/dl or ≥25% 2 to 7 d after contrast administration; (2) severe renal failure: An increase in serum creatinine to ≥3.0 mg/dl or the need for dialysis at 45 d; and (3) renal failure as a contributing cause of death (consensus of three independent physicians) at 45 d. Results: The incidence of CIN was 11% (70 of 633) among the 633 patients enrolled. Fifteen (2%) patients died within 45 d, including six deaths after study-defined CIN. Seven (1%) patients developed severe renal failure, six of whom had study-defined CIN. Of the six patients with CIN and severe renal failure, four died, and adjudicators determined that renal failure significantly contributed to all four deaths. Thus, CIN was associated with an increased risk for severe renal failure and death from renal failure. Conclusions: CIN occurs in >10% of patients who undergo CECT in the outpatient setting and is associated with a significant risk for severe renal failure and death.

The mortality rate for patients with acute renal failure (ARF) remains unacceptably high. Although dialysis removes waste products and corrects fluid imbalance, it does not perform the absorptive, metabolic, endocrine, and immunologic functions of normal renal tubule cells. The renal tubule assist device (RAD) is composed of a conventional hemofilter lined by monolayers of renal cells. For testing whether short-term (up to 72 h) treatment with the RAD would improve survival in patients with ARF compared with conventional continuous renal replacement therapy (CRRT), a Phase II, multicenter, randomized, controlled, open-label trial involving 58 patients who had ARF and required CRRT was performed. Forty patients received continuous venovenous hemofiltration + RAD, and 18 received CRRT alone. The primary efficacy end point was all-cause mortality at 28 d; additional end points included all-cause mortality at 90 and 180 d, time to recovery of renal function, time to intensive care unit and hospital discharge, and safety. At day 28, the mortality rate was 33% in the RAD group and 61% in the CRRT group. Kaplan-Meier analysis revealed that survival through day 180 was significantly improved in the RAD group, and Cox proportional hazards models suggested that the risk for death was approximately 50% of that observed in the CRRT-alone group. RAD therapy was also associated with more rapid recovery of kidney function, was well tolerated, and had the expected adverse event profile for critically ill patients with ARF.

Study objective Recent studies have demonstrated that a single episode of acute kidney injury from a number of causes can increase the risk of severe long-term outcomes, including major cardiovascular events and death. We tested the hypothesis that patients who develop acute kidney injury consistent with contrast-induced nephropathy after contrast-enhanced computed tomography (CT) imaging are at increased risk of major adverse events at 1 year. Methods We followed a prospective, heterogeneous cohort of consecutive emergency department patients undergoing contrast-enhanced CT for the outcomes of acute kidney injury consistent with contrast-induced nephropathy and major adverse events, defined as the combined outcome of death (all cause), renal failure, myocardial infarction, and stroke or other arterial vascular events, in any anatomic territory, requiring invention within 1 year. The primary outcome, major adverse events, was determined by the consensus of 2 of 3 blinded adjudicators. Results We followed 633 patients undergoing contrast-enhanced CT, of whom 11% developed acute kidney injury consistent with contrast-induced nephropathy and 15% (95/633; 95% confidence interval [CI] 12% to 18%) experienced at least 1 major adverse event within 1 year, including 7% (46/633; 95% CI 5% to 9%) who died. The development of acute kidney injury after contrast-enhanced CT was associated with an increased risk of 1-year major adverse event: the incident risk ratio was 4.01 (95% CI 2.61 to 6.05) and was 2.36 (95% CI 1.49 to 3.75) after adjusting for age, existing coronary artery disease, active malignancy, and 1 or more additional exposures to intravascular iodinated contrast media. Conclusion The development of acute kidney injury after contrast-enhanced CT was associated with a 2-fold increase in 1-year major adverse events. Further research is needed to validate this observation.

Objective Acute kidney injury (AKI) is a highly morbid condition in critically ill patients that is associated with high mortality. Previous clinical studies have demonstrated the safety and efficacy of the Selective Cytopheretic Device (SCD) in the treatment of AKI requiring continuous renal replacement therapy in the intensive care unit (ICU). Design, Setting, Patients A randomized, controlled trial of 134 ICU patients with AKI, 69 received continuous renal replacement therapy (CRRT) alone and 65 received SCD therapy. Results No significant difference in 60-day mortality was observed between the treated (27/69; 39%) and control patients (21/59; 36%, with six patients lost to follow up) in the intention to treat (ITT) analysis. Of the 19 SCD subjects (CRRT+SCD) and 31 control subjects (CRRT alone) who maintained a post-filter ionized calcium (iCa) level in the protocol’s recommended range (≤ 0.4mmol/L) for greater or equal to 90% of the therapy time, 60-day mortality was 16% (3/19) in the SCD group compared to 41% (11/27) in the CRRT alone group (p = 0.11). Dialysis dependency showed a borderline statistically significant difference between the SCD treated versus control CRRT alone patients maintained for ≥ 90% of the treatment in the protocol’s recommended (r) iCa target range of ≤ 0.4 mmol/L with values of, 0% (0/16) and 25% (4/16), respectively (P = 0.10). When the riCa treated and control subgroups were compared for a composite index of 60 day mortality and dialysis dependency, the percentage of SCD treated subjects was 16% versus 58% in the control subjects (p

Objective To examine the relationship between changes in anti–double-stranded DNA (anti-dsDNA) antibody levels and the risk of renal flare in patients with systemic lupus erythematosus (SLE), using data from 2 randomized, controlled trials. Methods Analyses were based on 487 patients with SLE and a history of lupus nephritis who had an anti-dsDNA antibody titer ≥15 IU/ml at baseline, as measured by Farr assay. Results are presented for the combined population of patients, the placebo arms, and the drug treatment arms in which a dsDNA-based bioconjugate (abetimus sodium; LJP 394) was used. Results Changes in anti-dsDNA antibody levels were inversely correlated with changes in the C3 level (P < 0.0001 in both trials). Cox proportional hazards regression models showed that changes in anti-dsDNA antibody levels correlated with the risk of renal flare. The models predicted that a point estimate of a 50% reduction in anti-dsDNA antibody levels is associated with a 52% reduction (95% confidence interval [95% CI] 26–68%, nominal P = 0.0007) and a 53% reduction (95% CI 33–69%, nominal P < 0.0001) in the risk of renal flare in the 2 trials, respectively. In the 2 trials, the incidence of renal flare was lower in patients with sustained reductions in anti-dsDNA antibodies (3.0% and 4.1%, respectively) than in patients with stable or increasing antibody levels (21.3% and 20.3%, respectively). Conclusion Changes in anti-dsDNA antibody levels were directly correlated with the risk of renal flare and inversely correlated with changes in the C3 level. Reducing anti-dsDNA antibody levels may represent a therapeutic objective in SLE patients with lupus nephritis, because it is associated with a reduced risk of renal flare.

IgA nephropathy is one of the most common causes of glomerulonephritis in the world and is characterized histologically by the deposition of polymeric forms of IgA within the mesangium and in some cases along the glomerular capillary wall.(1) Proliferative and crescenteric forms of IgA are associated with nephrotic range proteinuria, accelerated hypertension, and a more rapid decline toward end-stage renal disease. Previous attempts to categorize the incidence and clinical significance of proliferative IgA nephropathy have given conflicting results. This is in part the result of the lack of a uniform nomenclature and the failure of clinical therapies to prolong renal survival in specific subgroups. In the present study, we performed a prospective open-label trial of pulse solumedrol and intravenous cyclophosphamide in 20 patients with IgA nephropathy and at least 10% cellular crescents or endocapillary proliferation on renal biopsy. Seventeen patients underwent repeat kidney biopsies after 6 months of therapy, and the morphologic response to treatment was assessed using a modified systemic lupus erythematosis (SLE) histologic activity and chronicity index score. To determine the long-term efficacy of intravenous cyclophosphamide on renal survival, the results of the treated patients were compared with 12 untreated historical controls. Pulse solumedrol and intravenous cyclophosphamide effectively reduced peak serum creatinine, degree of proteinuria, the rate of decline in renal function, and the incidence of end-stage renal disease at 36 months.

ContextThe development of contrast-induced nephropathy in patients undergoing invasive cardiac procedures is associated with a marked increase in cardiovascular morbidity and mortality. Fenoldopam mesylate, a specific agonist of the dopamine-1 receptor, preserves renal blood flow after iodinated contrast administration and has shown promise in ameliorating contrast nephropathy in previous observational and small randomized trials.ObjectiveTo examine the efficacy of fenoldopam mesylate in preventing contrast nephropathy after invasive cardiovascular procedures.DesignProspective, placebo-controlled, double-blind, multicenter randomized trial with serial serum creatinine levels measured at a central biochemistry laboratory (at baseline and 1, 24, 48, and 72 to 96 hours after study drug administration) and 30-day clinical follow-up.Patients and SettingBetween March 2001 and July 2002, 315 patients with creatinine clearance less than 60 mL/min (1.00 mL/s) at 28 centers in the United States were randomized to receive fenoldopam mesylate (n = 157) or placebo (n = 158).InterventionsPatients were hydrated and randomized to receive intravenous fenoldopam (0.05 µg/kg/min titrated to 0.10 µg/kg/min) vs matching placebo, starting 1 hour prior to angiography and continuing for 12 hours.Main Outcome MeasureContrast-induced nephropathy, defined as an increase of 25% or more in serum creatinine level within 96 hours postprocedure.ResultsMean (SD) patient age was 70 (11) years, and 49% had diabetes mellitus. Mean (SD) baseline creatinine clearance was 29.0 (10.0) mL/min (0.48 [0.16] mL/s) (range, 7.5-56.8 mL/min [0.12-0.94 mL/s]), and 157 (108) mL of contrast was administered during the procedures. The primary end point of contrast-induced nephropathy occurred in 33.6% of patients assigned to receive fenoldopam vs 30.1% assigned to receive placebo (relative risk, 1.11; 95% confidence interval, 0.79-1.57; P = .61). There were no significant differences in the 30-day rates of death (2.0% vs 3.8%, P = .50), dialysis (2.6% vs 1.9%, P = .72), or rehospitalization (17.6% vs 19.9%, P = .66) in fenoldopam vs placebo randomized patients, respectively.ConclusionThe selective dopamine-1 agonist fenoldopam mesylate does not prevent further renal function deterioration after contrast administration in patients with chronic renal insufficiency.

To determine whether LJP 394 delays or prevents renal flare in patients with systemic lupus erythematosus (SLE) and a history of renal disease.In a 76-week, double-blind, placebo-controlled study, 230 SLE patients were randomized to receive 16 weekly doses of 100 mg of LJP 394 or placebo, followed by alternating 8-week drug holidays and 12 weekly doses of 50 mg of LJP 394 or placebo. An assay measuring the affinity of the serum IgG fraction for the DNA epitope of LJP 394 identified a high-affinity population of patients (189 of 213 patients; 89% taking LJP 394 and 90% taking placebo). Analyses were performed on both the intent-to-treat population and the high-affinity population.Anti-double-stranded DNA antibodies decreased and C3 levels tended to increase during treatment with LJP 394. In the intent-to-treat population, the time to renal flare was not significantly different between treatment groups, but patients taking LJP 394 had a longer time to institution of high-dose corticosteroids and/or cyclophosphamide (HDCC) and required 41% fewer treatments with HDCC. In the high-affinity population, the LJP 394 group experienced a longer time to renal flare, 67% fewer renal flares, longer time to institution of HDCC, and 62% fewer HDCC treatments compared with the placebo group. In patients with serum creatinine levels/=1.5 mg/dl at study entry, those taking LJP 394 had 50% fewer renal flares; no renal flares were observed in the high-affinity group taking LJP 394. Serious adverse events were observed in 25 of the 114 LJP 394-treated patients (21.9%) and 34 of the 116 placebo-treated patients (29.3%).Treatment with LJP 394 in patients with high-affinity antibodies to its DNA epitope prolonged the time to renal flare, decreased the number of renal flares, and required fewer HDCC treatments compared with placebo. The study drug appeared to be well tolerated.

Heat shock proteins (HSP) are components of the steroid receptor complex and are released into the cell cytosol after hormone binding. We tested whether HSPs released from steroid receptors mediate an increase in calcineurin phosphatase activity by steroid hormones. Aldosterone increased calcineurin activity in microdissected rat cortical collecting ducts (CCD) and connecting tubules, but not in proximal tubules, medullary thick ascending limb, or outer medullary collecting ducts. In contrast, 5 microM dexamethasone increased calcineurin activity in both CCD and proximal tubules. Aldosterone increased CCD calcineurin activity after 30 min and this response was blocked by spironolactone, but not by actinomycin D. An antibody recognizing HSP-56 did not change basal calcineurin activity, but completely blocked the stimulation of calcineurin by aldosterone. Rapamycin, an immunosuppressive drug that stabilizes the HSP-steroid receptor complex, also blocked the aldosterone response, whereas HSP-90 or HSP-70 increased calcineurin activity in permeabilized CCD. In summary, (a) aldosterone increases calcineurin activity in CCD through a transcription-independent process; (b) maneuvers inactivating HSP-56 or slowing HSP disassociation from the receptor complex blocks stimulation of calcineurin by steroid hormones; (c) HSP-90 and HSP-70 increase CCD calcineurin activity in the absence of steroid hormone. We conclude that HSPs released from transformed steroid receptors can stimulate calcineurin activity through a transcription-independent pathway.

Evidence that the inhibition of Na + /K + -ATPase activity by FK506 involves calcineurin. We reported that cyclosporin A (CsA) inhibits Na + /K + -ATPase activity in specific segments of the rat nephron. In this study, we tested the hypothesis that cyclosporin A reduces Na + /K + -ATPase activity through inhibition of calcineurin. In T cells, cyclosporin A and FK506 bind to immunophilins and inhibit the phosphatase activity of calcineurin; Rapamycin and SDZ 220-384 also bind to immunophilins but do not change calcineurin activity. Na + /K + -ATPase activity was measured in microdissected rat proximal tubule (S2 subsegment), medullary thick ascending limb (mTAL), and cortical collecting duct (CCD). First we found that two inhibitors of calcineurin, pentafluorophenol (PFP, 100 mM) and peptide 412 (1 mM), significantly reduced Na + /K + -ATPase activity in the CCD by 78% and 70%, respectively. In CCDs, FK506 inhibited Na+/K+-ATPase activity by 61 to 85% at concentrations of 1.5 to 6 ng/ml, but not at 0.5 ng/ml. FK506 (6 ng/ml) inhibited Na+/K+-ATPase activity in mTALs by 56% but did not inhibit it in S2s or glomeruli. In contrast, Rapamycin (12.5 ng/ml) did not change Na+/K+-ATPase activity in CCDs or mTALs, but at a concentration of 12.5 µg/ml did block the inhibitory effect of FK506 (6 ng/ml) in both segments. SDZ 220-384 (600 ng/ml) did not change Na + /K + -ATPase activity in CCDs. Thus, in CCDs and mTALs: (1) FK506, like cyclosporin A, inhibits Na + /K + -ATPase activity; (2) Rapamycin and SDZ 220-384 do not inhibit Na + /K + -ATPase activity; and (3) Rapamycin prevents FK506-induced inhibition of Na + /K + -ATPase activity. These responses may be explained by a direct inhibition of calcineurin activity yielding lower Na + /K + -ATPase activity in CCDs and mTALs.