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Onco-nephrology has been a growing field within the adult nephrology scope of practice. Even though pediatric nephrologists have been increasingly involved in the care of children with different forms of malignancy, there has not been an emphasis on developing special expertise in this area. The fast pace of discovery in this field, including the development of new therapy protocols with their own kidney side effects and the introduction of the CD19-targeted chimeric antigen receptor T cell (CAR-T) therapy, has introduced new challenges for general pediatric nephrologists because of the unique effects of these treatments on the kidney. Moreover, with the improved outcomes in children receiving cancer therapy come an increased number of survivors at risk for chronic kidney disease related to both their cancer diagnosis and therapy. Therefore, it is time for pediatric onco-nephrology to take its spot on the expanding subspecialties map in pediatric nephrology. [ABSTRACT FROM AUTHOR]

Background and objectives: Contrast-induced nephropathy (CIN) is a relatively common complication following primary coronary angiography (CAG) or percutaneous coronary intervention (PCI), especially in at-risk patients. The goal of this study is to evaluate the role of pre-procedural serum osmolarity as a risk factor for CIN in patients undergoing elective CAG for stable coronary artery disease (CAD). Materials and methods: A total of 356 stable CAD patients scheduled to undergo CAG or PCI were included in this two-center study. Serum osmolarity was calculated on admission. CIN was defined according to the KDIGO criteria. Results: There were 45 (12.6%) patients who developed CIN 48–72 h after CAG or PCI. CIN patients had a higher prevalence of diabetes (51.1% in those with CIN vs 24.4% in those without CIN, p < 0.001), higher serum glucose (129 mg/dL in those with CIN vs 108 mg/dL in those without CIN, p < 0.001), blood urea nitrogen (22.4 mg/dL in those with CIN vs 19.0 mg/dL in those without CIN, p = 0.01) and serum osmolarity (294.2 mOsm in those with CIN vs 290.1 mOsm in those without CIN, p < 0.001) levels, had received a higher dose of contrast (250 mL in those with CIN vs 200 mL in those without CIN, p = 0.03) but had lower hemoglobin (12.9 g/dL in those with CIN vs 13.6 g/dL in those without CIN, p = 0.04) level. In multivariate analysis, serum osmolarity [odds ratio (OR) 1.11; 95% confidence interval (CI) 1.04–1.18 for each mOsm/L increase; p = 0.001], diabetes (OR 2.43, 95% CI 1.26–4.71; p = 0.01), C-reactive protein (OR 1.04, 95% CI 1.01–1.08 for each mg/dL increase; p = 0.02) and contrast volume (OR 34.66, 95% CI 1.25–962.22 for each L increase; p = 0.04) remained as independent predictors of CIN. Serum sodium, glucose and blood urea nitrogen contributed to the excess serum osmolarity of CIN patients. Conclusion: Serum osmolarity is a cheap and widely available marker that can reliably predict CIN after CAG or PCI. Future research should focus on determining a clinically optimal cutoff for serum osmolarity that would warrant preventive interventions. Furthermore, later research may investigate the role of serum osmolarity not only as a risk factor but also as a pathogenetic mechanism underlying CIN. [ABSTRACT FROM AUTHOR]

Purpose: Contrast-induced acute kidney injury is a prominent complication following cardiac catheterization, though the risk has progressively decreased in recent times with appropriate risk stratification and use of safer contrast agents. Despite data supporting further lowering of risk with the iso-osmolar agent, iodixanol, uptake has lagged, perhaps due to increased upfront cost of this agent. We undertook an economic analysis to estimate the cost-effectiveness of a strategy utilizing iodixanol compared to using a low-osmolar contrast agent.Methods: We created a Markov model to evaluate the two strategies, and included a differential relative risk of contrast-induced acute kidney injury, based on a systematic review of the literature. Downstream clinical events, including need for dialysis and mortality, were modeled using data from existing published literature. A third-party payer perspective was utilized for the analysis and presentation of the primary economic analysis.Results: The strategy of using iodixanol dominated in both the low-risk and high-risk base case analyses. However, the difference was quite small in the low-risk scenario (lifetime cost: C$678,034 vs. C$678,059 and life expectancy: 19.80 vs. 19.72 years). The difference was more marked (life expectancy 15.65 vs. 14.15 years and cost C$680,989 vs. C$682,023) in the high-risk case analysis. This was robust across most of the variables tested in sensitivity analyses.Conclusion: The use of iodixanol, compared with low-osmolar contrast agents, for cardiac catheterization, results in a small benefit clinical outcomes, and in a savings in direct healthcare costs. Overall, our analysis supports the use of iodixanol for cardiac catheterization, especially in patients at high risk of acute kidney injury. [ABSTRACT FROM AUTHOR]

Background: It has been shown that beta-glucan (BG), which has antioxidant and immunomodulatory effects, attenuats renal ischemia-reperfusion injury. We aimed to investigate whether BG might have a preventive role against the development of contrast-induced nephropathy and to compare its effect with nebivolol (Nb) and N-acetylcysteine (NAC). Methods: Thirty-six Wistar albino female rats were randomly divided into six groups ( n = 6 each): control, contrast media (CM), BG, BG + CM, Nb + CM, and NAC + CM. With the exception of control and CM groups, the others were given drugs orally once a day for 5 days. Kidney function parameters, inflammatory parameters, and serum and renal tissue oxidative stress markers were measured. Results: Increases of serum creatinine and blood urea nitrogen levels were significantly higher ( p < 0.05) in the CM group only. Absolute changes of serum creatinine levels in BG, BG + CM and Nb + CM groups were significantly lower than those in the CM group ( p < 0.05). Serum levels of advanced oxidation protein products and malondialdehyde were significantly less ( p < 0.05) in the BG group compared to the CM group. Histopathological lesions in the CM group were more advanced ( p < 0.05). No significant differences between the BG + CM, Nb + CM and NAC + CM groups were found with regard to histopathological findings. Conclusion: This study suggests that BG protects or ameliorates against contrast-induced nephropathy. Its beneficial effects may be similar to or greater than those of Nb or NAC. [ABSTRACT FROM AUTHOR]

Background and Aim: Previous studies have demonstrated that endogenous bone morphogenic protein-7 (BMP-7) level is reduced in acute kidney injury and administration of exogenous BMP-7 has a beneficial effect on kidney function. In spite of preventive management, contrast-induced nephropathy (CIN) is still the third cause of acute deterioration of kidney function in hospitalized patients. With this background in mind, we studied changes in serum BMP-7 in a group of patients with chronic kidney disease and contrast-induced nephropathy. Materials and Methods: We enrolled 45 consecutive adult patients with a baseline serum creatinine ≥1.4 mg/dl admitted for coronary angiography. We measured serum BMP-7 levels before and 48 h after coronary angiography. The primary end point was the development of CIN, defined as an increase in serum creatinine concentration by 0.25 mg/dl or 25% over the baseline value within 72 h from contrast exposure. Results: Overall, CIN occurred in 8 (17%) patients. The concentrations of serum BMP-7 were significantly decreased in the CIN group compared to baseline (488.6 ± 56.8 vs. 356.4 ± 24.8, P = 0.01); in contrast, the concentration of BMP-7 level did not change in patients without CIN (444.6 ± 54.6 vs. 440.0 ± 53.9, P = 0.09). Conclusion: BMP-7 level significantly decreases in patients who develop CIN after coronary angiography. Therefore, BMP-7 might be a diagnostic biomarker for CIN and a possibly promising agent for the treatment of CIN. [ABSTRACT FROM AUTHOR]

The correct strategy to prevent radiocontrast-induced nephropathy (CIN) in high-risk patients going for cardiac angiography is widely debated in the literature. It is well known that chronic kidney disease (CKD) patients with lower estimated glomerular filtration rates (eGFRs) at baseline are at the greatest risk for a significant loss in kidney function, or even dialysis after a contrast load. For this reason potentially life-saving procedures such as angiography are sometimes withheld or delayed. We describe a case series of 31 well-characterized patients with CKD who underwent cardiac or peripheral vessel angiography, and patients with renal artery stenosis (RAS) who underwent angioplasty and stenting. All were treated with a standardized outpatient protocol of withholding their diuretics and angiotensin-converting enzyme (ACE) inhibitors (ACEs)/angiotensin receptor blockers (ARBs) the day prior to and 2 days after the procedure, restarting the diuretic the day after the procedure and the ACE inhibitor/ARB after 2 days. Calcium channel blockers were prescribed for the 2 days prior to and 2 days after the procedure. Patients had bloodwork on days 2–3 and days 7–10 post-procedure. The patients had a mean baseline creatinine of 214 µmol/l (SD = 123), ranging from 87 to 535 µmol/l. This corresponded to a mean baseline eGFR of 34 ml/min (SD = 15.8), ranging from a minimum of 12–59 ml/min. The mean age was 64 ± 13.8 years; 48% were male and 11 (35.5%) were diabetic. All patients enrolled had a baseline eGFR of less than 60 ml/min as calculated by the Modification of Diet in Renal Disease (MDRD) formula. Based on pre-procedure CKD stage, 21 (68%) were stage 3 (eGFR 30–60 ml/min), 5 (16%) were stage 4 (eGFR 15–30 ml/min), and 6 (19%) were stage 5 (eGFR < 15 ml/min). No patient required urgent hemodialysis following their angiography. All patients have had a longitudinal follow up of 26 months, and none developed any change in the rate of progression from prior to procedure. This case series provides data in support of a conservative, outpatient-based approach for high-risk CKD patients going for cardiac angiography. This protocol warrants further study in randomized control trials. [ABSTRACT FROM AUTHOR]

Objective: The prevention of contrast-mediated nephropathy (CMN), which accounts for considerable morbidity and mortality, remains a vexing problem. Contrast induced renal vasoconstriction is believed to play a pivotal role in the CMN mechanism. The aim of this pilot study was to examine the safety and efficacy of two doses of the prostacyclin analogue iloprost in preventing CMN in high-risk patients undergoing a coronary procedure. Methods: Forty-five patients undergoing coronary angiography and/or intervention who had a serum creatinine concentration ≥1.4 mg/dL were randomized to receive iloprost at 1 or 2 ng/kg/min or placebo, beginning 30–90 minutes before and terminating 4 hours after the procedure. CMN was defined by an absolute increase of serum creatinine ≥0.5 mg/dL or a relative increase of ≥25% measured 2 to 5 days after the procedure. Study drug infusion was discontinued in 2 patients in the low-dose iloprost group due to flush/nausea and in 5 patients in the high-dose group due to severe hypotension. Results: The mean creatinine concentration change in the placebo group (0.02 mg/dL) was unfavorable compared to that in the low-dose iloprost group (-0.11 mg/dL; p=0.08) and high-dose iloprost group (-0.23 mg/dL; p=0.048). The difference between the absolute changes in creatinine clearance was favorable compared to placebo for both the low (mean difference 6.1 mL/min, 95%CI -0.5 to 12.8 mL/min, p=0.07) and the high-dose iloprost group (11.8 mL/min, 95%CI 4.7 to 18.8 mL/min, p=0.002). Three cases of CMN were recorded; all in the placebo group (p=0.032). Conclusions: The results of this pilot study suggest that prophylactic administration of iloprost may effectively prevent CMN, but higher dosages are connected with substantial tolerability issues. [ABSTRACT FROM AUTHOR]

Reactive oxygen species play a major role in the pathogenesis of contrast-induced nephropathy (CN). Hydration with sodium bicarbonate (HCO) can reduce the incidence of CN in high-risk patients, suggesting a direct causal relationship between low pH of tubular fluid and enhanced activity of generated reactive oxygen species to damage renal tubular cells. Whether acetazolamide (AZ), a carbonic anhydrase inhibitor, is more effective than HCO unknown. Ninety-six children with stable chronic renal insufficiency were randomly assigned to receive either a 154 mEq/L infusion of sodium bicarbonate (HCO) ( n = 46) or 0.9% sodium chloride plus oral AZ ( n = 50) at a rate of 3 ml/kg/hr for 1 hour before and 1 ml/kg/hr for 6 hours after the radiographic procedure. Serum creatinine concentration (Scr) was measured before and 48 hours after the procedure. The primary endpoint was an increase in the Scr concentration of ≥25% 48 hours after the contrast administration. The baseline clinical and biochemical characteristics of the two groups were similar. The mean Scr concentration after contrast administration was significantly lower in the AZ group ( p = 0.02) than in the HCO group ( p = 0.27). The mean absolute decrease in Scr concentration at 48 hours was significantly greater in the AZ group ( p < 0.01). Four of the 46 patients (8.7%) in the HCO group had an increase in the Scr concentration of ≥25% compared with none of the 50 patients (0%) in the AZ group ( p = 0.049). Thus, compared to HCO, AZ plus saline hydration was more effective for the prevention CN after radiographic procedure. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine if the image quality of gadolinium digital subtraction angiography (DSA) can be improved by the addition of small quantities of iodinated contrast to gadolinium. The optical density (OD) of a mixture of four parts gadolinium-based contrast to one part iodinated contrast was measured through a phantom study and compared to that of full-strength gadolinium, full strength iodinated contrast, and a 20% solution of iodinated contrast. We also compared the clinical image quality of the mixture of gadolinium-based contrast and iodinated contrast relative to full-strength gadolinium and full strength iodinated contrast during DSA. The DSA image quality of the gadolinium-iodinated contrast mixture was significantly improved relative to images obtained with full-strength gadolinium and compared favorably to that obtained with full-strength iodinated contrast. The phantom data showed that the OD of the gadolinium-iodinated contrast mixture was much greater than that of full strength gadolinium and the 20% iodinated contrast solution. The increase in OD was greater than that expected from a simple additive effect of the OD of the contrast agents. Adding a small amount of iodinated contrast to gadolinium results in a significant improvement in the radiographic density and DSA image quality of gadolinium. This simple technique appears to overcome one of the major limitations of gadolinium-based angiography-poor radiographic density-while continuing to minimize the volume of administered iodinated contrast. [ABSTRACT FROM AUTHOR]

Contrast nephropathy (CN), a well-known complication of intravascular contrast medium, is associated with dense cortical nephrograms. These may be detected on unenhanced computed tomography (CT). We report the initial findings of a series of patients at risk for CN who received contrast for coronary arteriography or aortic arch angiography. Unenhanced CT scans were performed 22-26 h after contrast, and the mean cortical attenuation measured. These results were correlated with serial blood urea nitrogen (BUN) and serum creatinine measurements. The patients in this study, all of whom had either elevated baseline creatinine values, were over 73 years or both, had a high incidence of cortical contrast retention and contrast nephropathy. [ABSTRACT FROM AUTHOR]

This Practice Point commentary discusses the findings of a prospective observational study by Weisbord et al. that attempted to quantify the incidence and outcomes of contrast-induced acute kidney injury in patients with stage 3 chronic kidney disease (CKD). These data are set in the context of recent observations linking acute kidney injury with the progression of CKD to end-stage renal disease. The commentary also asks whether standard short-term clinical outcome measures--i.e, changes in serum creatinine--are adequate to assess the risk of disease progression in patients with mild-to-moderate CKD. [ABSTRACT FROM AUTHOR]

BACKGROUND There is controversy surrounding the efficacy of sodium bicarbonate and N-acetylcysteine for the prevention of contrast nephropathy. OBJECTIVE To evaluate the effects of sodium bicarbonate and N-acetylcysteine, used together and alone, on the risk of contrast nephropathy. DESIGN AND INTERVENTION Individuals aged ≥17 years who received an intravenous contrast agent during the period 1 April 2004 to 30 May 2005 at the Mayo Clinic, Rochester, MN were included in this retrospective analysis if they had at least 1 serum creatinine value recorded within the 7 days before contrast administration and 1 value recorded within the 7 days after contrast administration. Administration of intravenous sodium bicarbonate or oral N-acetylcysteine within 48 h of contrast exposure was noted. A pre-exposure serum creatinine level >707 µmol/l (>8mg/dl), a history of dialysis, and use of sodium bicarbonate for continuous renal replacement therapy were exclusion criteria. OUTCOME MEASURE The primary end point, contrast nephropathy, was defined as an increase in serum creatinine level of ≥25% or >44 pmol/l (>0.5 mg/dl) within 7 days of contrast exposure. RESULTS Serum creatinine data were available for >90% of cases in which a prophylactic agent was used. After exclusion of 27,945 ineligible patients, 7,977 patients (11,516 contrast exposures) remained for analysis. Contrast nephropathy occurred in 1,343 cases of contrast exposure (11.7%). The rate of contrast nephropathy was 11% in the 'no treatment' group (i.e. patients who did not receive sodium bicarbonate or N-acetylcysteine; 10,411 exposures), 15% in the group that received both sodium bicarbonate and N-acetylcysteine (221 exposures), 15% in the group that received N-acetylcysteine only (616 exposures) and 31% in the sodium-bicarbonate-only group (268 exposures). Patients who received sodium bicarbonate or N-acetylcysteine (or both) were older and more likely to have comorbidities than patients who did not receive these agents; those who received sodium bicarbonate alone were younger and less likely to have comorbidities than those who received N-acetylcysteine alone. After adjustment for predictors of contrast nephropathy (including age, previous contrast exposure and diabetes mellitus), sodium bicarbonate alone was associated with a significantly increased risk of contrast nephropathy compared with no treatment (odds ratio [OR] 3.10, 95% CI 2.28-4.18; P<0.001). This association persisted in a propensity scoring analysis, and when the cases were divided into subgroups on the basis of the particular sodium bicarbonate administration protocol used. N-acetylcysteine was not associated with any significant difference in the risk of contrast nephropathy, relative to no treatment, when used alone (OR 1.16, 95% CI 0.87-1.53; P=0.31) or with sodium bicarbonate (OR 1.07, 95% CI 0.68-1.65; P=0.75). Sodium bicarbonate alone was associated with a significantly higher adjusted risk of contrast nephropathy than N-acetylcysteine alone (OR 2.73, 95% CI 1.86-3.97; P<0.001). CONCLUSION The use of sodium bicarbonate for the prevention of contrast nephropathy should be reassessed. [ABSTRACT FROM AUTHOR]