Objectives This study aimed to determine the diagnostic and prognostic value of urinary biomarkers of intrinsic acute kidney injury (AKI) when patients were triaged in the emergency department. Background Intrinsic AKI is associated with nephron injury and results in poor clinical outcomes. Several urinary biomarkers have been proposed to detect and measure intrinsic AKI. Methods In a multicenter prospective cohort study, 5 urinary biomarkers (urinary neutrophil gelatinase–associated lipocalin, kidney injury molecule-1, urinary liver-type fatty acid binding protein, urinary interleukin-18, and cystatin C) were measured in 1,635 unselected emergency department patients at the time of hospital admission. We determined whether the biomarkers diagnosed intrinsic AKI and predicted adverse outcomes during hospitalization. Results All biomarkers were elevated in intrinsic AKI, but urinary neutrophil gelatinase-associated lipocalin was most useful (81% specificity, 68% sensitivity at a 104-ng/ml cutoff) and predictive of the severity and duration of AKI. Intrinsic AKI was strongly associated with adverse in-hospital outcomes. Urinary neutrophil gelatinase-associated lipocalin and urinary kidney injury molecule 1 predicted a composite outcome of dialysis initiation or death during hospitalization, and both improved the net risk classification compared with conventional assessments. These biomarkers also identified a substantial subpopulation with low serum creatinine at hospital admission, but who were at risk of adverse events. Conclusion Urinary biomarkers of nephron damage enable prospective diagnostic and prognostic stratification in the emergency department.

Patients with ESRD have high rates of depression, which is associated with diminished quality of life and survival. We determined whether individual cognitive behavioral therapy (CBT) reduces depression in hemodialysis patients with elevated depressive affect in a randomized crossover trial. Of 65 participants enrolled from two dialysis centers in New York, 59 completed the study and were assigned to the treatment-first group (n=33) or the wait-list control group (n=26). In the intervention phase, CBT was administered chairside during dialysis treatments for 3 months; participants were assessed 3 and 6 months after randomization. Compared with the wait-list group, the treatment-first group achieved significantly larger reductions in Beck Depression Inventory II (self-reported, P=0.03) and Hamilton Depression Rating Scale (clinician-reported, P,0.001) scores after intervention. Mean scores for the treatment-first group did not change significantly at the 3-month follow-up. Among participants with depression diagnosed at baseline, 89% in the treatment-first group were not depressed at the end of treatment compared with 38% in the wait-list group (Fisher's exact test, P=0.01). Furthermore, the treatment-first group experienced greater improvements in quality of life, assessed with the Kidney Disease Quality of Life Short Form (P=0.04), and interdialytic weight gain (P=0.002) than the wait-list group, although no effect on compliance was evident at follow-up. In summary, CBT led to significant improvements in depression, quality of life, and prescription compliance in this trial, and studies should be undertaken to assess the long-term effects of CBT on morbidity and mortality in patients with ESRD.

Background. Primary goal of this randomized, double-blind, placebo-controlled crossover study of Renadyl in end-stage renal disease patients was to assess the safety and efficacy of Renadyl measured through improvement in quality of life or reduction in levels of known uremic toxins. Secondary goal was to investigate the effects on several biomarkers of inflammation and oxidative stress. Methods. Two 2-month treatment periods separated by 2-month washout and crossover, with physical examinations, venous blood testing, and quality of life questionnaires completed at each visit. Data were analyzed with SAS V9.2. Results. 22 subjects (79%) completed the study. Observed trends were as follows (none reaching statistical significance): decline in WBC count (−0.51 × 109/L, P = 0.057) and reductions in levels of C-reactive protein (−8.61 mg/L, P = 0.071) and total indoxyl glucuronide (−0.11 mg%, P = 0.058). No statistically significant changes were observed in other uremic toxin levels or measures of QOL. Conclusions. Renadyl appeared to be safe to administer to ESRD patients on hemodialysis. Stability in QOL assessment is an encouraging result for a patient cohort in such advanced stage of kidney disease. Efficacy could not be confirmed definitively, primarily due to small sample size and low statistical power—further studies are warranted.

Two metrics, a rise in serum creatinine concentration and a decrease in urine output, are considered tantamount to the injury of the kidney tubule and the epithelial cells thereof (AKI). Yet neither criterion emphasizes the etiology or the pathogenetic heterogeneity of acute decreases in kidney excretory function. In fact, whether decreased excretory function due to contraction of the extracellular fluid volume (vAKI) or due to intrinsic kidney injury (iAKI) actually share pathogenesis and should be aggregated in the same diagnostic group remains an open question. To examine this possibility, we created mouse models of iAKI and vAKI that induced a similar increase in serum creatinine concentration. Using laser microdissection to isolate specific domains of the kidney, followed by RNA sequencing, we found that thousands of genes responded specifically to iAKI or to vAKI, but very few responded to both stimuli. In fact, the activated gene sets comprised different, functionally unrelated signal transduction pathways and were expressed in different regions of the kidney. Moreover, we identified distinctive gene expression patterns in human urine as potential biomarkers of either iAKI or vAKI, but not both. Hence, iAKI and vAKI are biologically unrelated, suggesting that molecular analysis should clarify our current definitions of acute changes in kidney excretory function.

Reimbursement for chronic dialysis consumes a substantial portion of healthcare costs for a relatively small proportion of the total population. Each country has a unique reimbursement system that attempts to control rising costs. Thus, comparing the reimbursement systems between countries might be helpful to find solutions to minimize costs to society without jeopardizing quality of treatment and outcomes. We conducted a survey of seven countries to compare crude reimbursement for various dialysis modalities and evaluated additional factors, such as inclusion of drugs or physician payments in the reimbursement package, adjustment in rates for specific patient subgroups, and pay for performance therapeutic thresholds. The comparison examines the United States, the province of Ontario in Canada, and five European countries (Belgium, France, Germany, The Netherlands, and the United Kingdom). Important differences between countries exist, resulting in as much as a 3.3-fold difference between highest and lowest reimbursement rates for chronic hemodialysis. Differences persist even when our data were adjusted for per capita gross domestic product. Reimbursement for peritoneal dialysis is lower in most countries except Germany and the United States. The United Kingdom is the only country that has implemented an incentive if patients use an arteriovenous fistula. Although home hemodialysis (prolonged or daily dialysis) allows greater flexibility and better patient outcomes, reimbursement is only incentivized in The Netherlands. Unfortunately, it is not yet clear that such differences save money or improve quality of care. Future research should focus on directly testing both outcomes.

Both mitogenic and inflammatory phenomena accompany the renal response to ischemic injury. Previous studies have shown that several nuclear-binding members of the immediate early genes are prominently expressed after renal ischemia and may underlie the mitogenic response to such injury. We now report on the expression of JE and KC, other growth-factor-responsive genes that code for small secreted glycoproteins with cytokine-like properties, which may play a role in inflammation. The expression of the immediate early genes JE and KC was determined in rat kidney tissue at varying time points after release of a 50-min period of bilateral renal hilar clamping. Relative levels of mRNA for JE and KC were analyzed by Northern blot analysis of cortical and outer stripe mRNA. KC mRNA rose rapidly to peak values at 1 h and returned toward low baseline levels by 24 h after release of the hilar clamp. By contrast, JE mRNA reached peak levels later and remained elevated for at least 96 h after ischemia. JE antigen was localized immunocytochemically to the apical regions of the cortical and medullary thick ascending limbs as well as in the lumen of the distal nephron in ischemic kidneys. Cells of the glomerulus and proximal tubules were negative for JE antigen. In contrast to the increase in JE and KC mRNA, steady-state levels of uromodulin (Tamm Horsfall) mRNA, a cytokine binding protein also made by the thick ascending limb, declined to virtually undetectable levels by 24 h after ischemia. Thus the increases in JE and KC are not generalized phenomena.(ABSTRACT TRUNCATED AT 250 WORDS)

Temporary renal ischemia is followed by increased DNA synthesis and cell division as the kidney restores the continuity of the renal epithelium. We sought to characterize some of the changes in proto-oncogene and growth factor expression during this proliferative response. Northern analysis of polyadenylated RNAs of kidney cortical and outer stripe of outer medullary tissue from male Sprague-Dawley rats was performed following release of renal hilar clamping of 50 minutes duration. Ischemia produced an increase in c-fos mRNA that reached a peak at one hour and declined rapidly to control levels by four hours after release of the clamp. A similar rapid increase and decrease in early growth response 1 (Egr 1) mRNA was noted. The response of these immediate early genes was typical of their response to mitogens, suggesting that they served a similar role in renal cell regeneration. Levels of c-Ki-ras and glyceraldehyde phosphate dehydrogenase mRNA were unchanged. Renal preproEGF mRNA decreased at two hours, was virtually absent by 24 hours and remained low for at least four days after ischemia. Urinary excretion of EGF fell immediately after release of ischemia and before the decline in preproEGF mRNA or SNGFR, suggesting post-transcriptional affects of ischemia on renal EGF production. EGF excretion returned to only 50% of control by day 21. Specific 125I-EGF binding increased in membrane fractions of cortex, outer medulla and inner medulla as early as 24 hours after release of the clamp. Cortical 125I-EGF binding increased in the proximal tubule but not in the glomerulus.(ABSTRACT TRUNCATED AT 250 WORDS)

| Every year, more than 110,000 Americans are newly diagnosed with end-stage renal disease and in the overwhelming majority, maintenance dialysis therapy is initiated. However, most patients, having received no predialysis nephrology care or dietary counseling, are inadequately prepared for starting treatment; furthermore, the majority of patients do not have a functioning permanent dialysis access. Annualized mortality in the USA in the first 3 months after starting dialysis treatment is approximately 45%; this high rate is possibly in part due to inadequate preparation for renal replacement therapy. Data from the Dialysis Outcomes and Practice Patterns study suggest that similar challenges exist in many parts of the world. Implementation of strategies that mitigate the risk of adverse consequences when starting dialysis are urgently needed. In this Review we present a step-by-step approach to tackling inadequate patient preparation, which includes identifying individuals with chronic kidney disease (CKD) who are most likely to need dialysis in the future, referring patients for education, timely placement of dialysis access and timely initiation of dialysis therapy. Treatment with dialysis might not be appropriate for some patients with progressive CKD; these individuals can be optimally managed with nondialytic, maximum conservative management.