Neutrophil Gelatinase–Associated Lipocalin and Contrast-Induced Acute Kidney Injury

Renal Biomarkers in the Early Detection of Acute Kidney Injury After Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

Cardiac surgery-associated (CSA) acute kidney injury (AKI) is a severe postoperative complication in patients undergoing off-pump coronary artery bypass grafting (OPCAB). Early detection of postoperative CSA-AKI may be key to improving patient outcomes. This study explored the use of renal biomarkers measured immediately after surgery for the early detection of CSA-AKI in patients undergoing OPCAB.Methods and Results: In all, 111 patients who underwent OPCAB at Kumamoto University Hospital between June 2020 and October 2022 were included in this study. Urinary neutrophil gelatinase-associated lipocalin, liver-type fatty acid-binding protein, and N-acetyl-β-D-glucosaminidase (NAG) were measured upon arrival in the intensive care unit (ICU) after surgery. AKI was diagnosed using KDIGO criteria. Of the 111 patients, 32 (28.8%) developed postoperative AKI. Regarding AKI staging, 19 (59.4%), 11 (34.4%), and 2 (6.3%) patients had Stage 1, 2, and 3 AKI, respectively. There were significant differences in chronic kidney disease, preoperative estimated glomerular filtration rate (eGFR), and NAG between the AKI and non-AKI groups. Multivariate analysis showed that preoperative eGFR (odds ratio [OR] for 5-mL/min/1.73 m2increase in eGFR 0.75; 95% confidence interval [CI] 0.63-0.89) and increasing urinary NAG concentrations at ICU admission (OR 2.44; 95% CI 1.30-4.60) were significant risk factors for CSA-AKI in OPCAB patients.

CONCLUSIONS

NAG and eGFR may be valuable biomarkers for the early detection of CSA-AKI in patients undergoing OPCAB.

Systemic reserve dysfunction and contrast-associated acute kidney injury following percutaneous coronary intervention

BACKGROUND

Developing contrast-associated acute kidney injury (CA-AKI) following percutaneous coronary intervention (PCI) is closely related to patient-related risk factors as well as contrast administration. The diagnostic and prognostic roles of neutrophil gelatinase-associated lipocalin (NGAL) in CA-AKI following PCI are not well established.

METHODS

Consecutive patients undergoing PCI were enrolled prospectively. CA-AKI was defined as an increase in the serum creatinine level ≥0.3 mg/dL within 48 hours or ≥1.5 times the baseline within 7 days after PCI. Serum NGAL concentrations were determined immediately before and 6 hours after PCI. The participants were classified into four NGAL groups according to the pre- and post-PCI NGAL values at 75th percentile.

RESULTS

CA-AKI occurred in 38 (6.4%) of 590 patients. With chronic kidney disease status (hazard ratio [HR] 1.63, 95% confidence interval [CI]: 1.06-2.52), NGAL groups defined by the combination of pre- and 6 h post-PCI values were independently associated with the occurrence of CA-AKI (HR 1.69, 95% CI: 1.16-2.45). All-cause mortality for 29-month follow-ups was different among NGAL groups (log-rank p<0.001). Pre-PCI NGAL levels significantly correlated with baseline cardiac, inflammatory, and renal markers. Although post-PCI NGAL levels increased in patients with larger contrast administration, contrast media made a relatively limited contribution to the development of CA-AKI.

CONCLUSION

In patients undergoing PCI, the combination of pre- and post-PCI NGAL values may be a useful adjunct to current risk-stratification of CA-AKI and long-term mortality. CA-AKI is likely caused by systemic reserve deficiency rather than contrast administration itself.

Definition, Staging, and Role of Biomarkers in Acute Kidney Injury in the Context of Cardiovascular Interventions

Acute kidney injury (AKI) is a frequently occurring complication of cardiovascular interventions, and associated with adverse outcomes. Therefore, a clear definition of AKI is of paramount importance to enable timely recognition and treatment. Historically, changes in the serum creatinine and urine output have been used to define AKI, and the criteria have evolved over time with better understanding of the impact of AKI on the outcomes. However, the reliance on serum creatinine for these AKI definitions carries numerous limitations including delayed rise, inability to differentiate between hemodynamics versus structural injury and assay variability to name a few.

Intravenous versus oral hydration to reduce the risk of postcontrast acute kidney injury after intravenous contrast-enhanced CT in patients with severe chronic kidney disease (ENRICH): a study protocol for a single-centre, parallel-group, open-labelled non-inferiority randomised controlled trial in Denmark

INTRODUCTION

Contrast-enhanced CT (CECT) is widely used for diagnostic purposes. The use of contrast medium carries a risk for postcontrast acute kidney injury (PC-AKI), especially in patients with AKI or chronic kidney disease (CKD). Current guidelines recommend prophylactic intravenous hydration to prevent PC-AKI in high-risk patients. Oral hydration is non-inferior to intravenous hydration in patients with moderate CKD, but it has not been evaluated in high-risk patients.

METHODS AND ANALYSIS

The ENRICH trial will enrol 254 patients with estimated glomerular filtration rate ≤30 mL/min/1.73 m2 undergoing intravenous CECT, who are block randomised (2-4-2) with stratification for CKD stage, diabetes status, and indication for referral to prophylactic treatment with oral or intravenous hydration. PC-AKI is defined as an absolute increase in SCr of >0.3 mg/dL or >1.5 from baseline at 2-5 days. Renal function will also be evaluated <90 days, <7 days and 1-3 days before intravenous CECT, and 25-40 days after intravenous CECT. Secondary outcomes include dialysis, renal adverse events, hospitalisation due to hydration-related or contrast-related sequelae, and all-cause mortality ≤30 days postcontrast. Pre- and postcontrast plasma and urinary biomarkers will be evaluated for diagnostic and prognostic accuracy of the primary and secondary outcomes.

ETHICS AND DISSEMINATION

Oral hydration is patient-friendly and less costly compared with intravenous hydration. If oral hydration is non-inferior to intravenous hydration in high-risk patients, it could be implemented as new hydration strategy, which will facilitate the clinical diagnosing of elective patients with severe CKD without unnecessary resource utilisation. The protocol is approved by the Regional Scientific Ethical Committee for Southern Denmark (S-20210126), and the Data Protection Agency (21/66779). The study is conducted in accordance with the Declaration of Helsinki. Positive as well as negative findings will be reported in international peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05283512.

Predictive and Prognostic Value of Serum Neutrophil Gelatinase-Associated Lipocalin for Contrast-Induced Acute Kidney Injury and Long-Term Clinical Outcomes after Percutaneous Coronary Intervention

Neutrophil gelatinase-associated lipocalin (NGAL) has been proposed as an early marker for estimating the risk of contrast-induced acute kidney injury (CI-AKI). However, the predictive value of baseline serum NGAL levels for CI-AKI remains unclear. Serum NGAL was measured before percutaneous coronary intervention in 633 patients with coronary artery disease. The primary clinical endpoints were a composite of major adverse cardiac and cerebrovascular events (MACCEs; cardiac death, myocardial infarction, stroke, and any revascularization). The mean follow-up duration was 29.4 months. Ninety-eight (15.5%) patients developed CI-AKI. Compared with patients without CI-AKI, baseline serum NGAL was higher in patients with CI-AKI (149.6 ± 88.8 ng/mL vs. 138.0 ± 98.6 ng/mL, p = 0.0279), although serum creatinine and estimated glomerular filtration rate were not different between groups. Patients in the highest tertile of baseline serum NGAL showed a significantly higher rate of MACCEs (10.5% vs. 3.8%, p = 0.02). Using the first tertile as a reference, the adjusted hazard ratios for MACCEs in patients in the second and third tertiles of NGAL were 2.151 (confidence interval (CI) 0.82 to 5.59, p = 0.116) and 2.725 (CI 1.05 to 7.05, p = 0.039), respectively. Baseline serum NGAL is a reliable marker for predicting CI-AKI, and high serum NGAL levels are associated with a higher incidence rate of long term MACCEs.

Decongestion, kidney injury and prognosis in patients with acute heart failure

BACKGROUND

In patients with acute heart failure (AHF), the development of worsening renal function with appropriate decongestion is thought to be a benign functional change and not associated with poor prognosis. We investigated whether the benefit of decongestion outweighs the risk of concurrent kidney tubular damage and leads to better outcomes.

METHODS

We retrospectively analyzed data from the AKINESIS study, which enrolled AHF patients requiring intravenous diuretic therapy. Urine neutrophil gelatinase-associated lipocalin (uNGAL) and B-type natriuretic peptide (BNP) were serially measured during the hospitalization. Decongestion was defined as ≥30% BNP decrease at discharge compared to admission. Univariable and multivariable Cox models were assessed for one-year mortality.

RESULTS

Among 736 patients, 53% had ≥30% BNP decrease at discharge. Levels of uNGAL and BNP at each collection time point had positive but weak correlations (r ≤ 0.133). Patients without decongestion and with higher discharge uNGAL values had worse one-year mortality, while those with decongestion had better outcomes regardless of uNGAL values (p for interaction 0.018). This interaction was also significant when the change in BNP was analyzed as a continuous variable (p < 0.001). Although higher peak and discharge uNGAL were associated with mortality in univariable analysis, only ≥30% BNP decrease was a significant predictor after multivariable adjustment.

CONCLUSIONS

Among AHF patients treated with diuretic therapy, decongestion was generally not associated with kidney tubular damage assessed by uNGAL. Kidney tubular damage with adequate decongestion does not impact outcomes; however, kidney injury without adequate decongestion is associated with a worse prognosis.

Value of point-of-care neutrophil gelatinase associated lipocalin in early diagnosis of acute kidney injury in patients with left ventricular systolic dysfunction after coronary angiography

BACKGROUND

Increased neutrophil gelatinase-associated lipocalin (NGAL) levels are associated with toxic or ischemic renal injury.

OBJECTIVE

This study aimed to assess the usefulness of serial NGAL measurements with a point-of-care assay in patients with left ventricular systolic dysfunction (LVSD) for earlier detection of contrast-induced nephropathy (CIN).

MATERIALS AND METHODS

A total of 84 patients with LVSD patients referred for coronary angiography were consecutively enrolled in the study. The study population was divided into two groups as the CIN and the non-CIN groups according to the CIN's determination. The serum creatinine levels were calculated 24 h before the procedure and at the 48th and 72nd h after the cardiac catheterization. The plasma NGAL concentration was measured before and at 4 and 24 h after the cardiac catheterization.

RESULTS

Baseline and serial NGAL levels were significantly higher in patients with CIN compared to the patients without CIN. NGAL 24th h levels after the index procedure were found to be an independent and significant predictor of CIN in multivariate analysis.

CONCLUSIONS

Serial point-of-care NGAL measurements might help earlier detection of CIN in patients with heart failure after coronary angiography.

Contrast-Induced Nephropathy in Patients Undergoing Staged Versus Concomitant Transcatheter Aortic Valve Implantation and Coronary Procedures

Background

The impact of staged versus concomitant coronary procedures on renal function in patients with aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) remains unclear.

Methods and Results

Three‐hundred thirty‐nine patients undergoing coronary procedures and TAVI as a staged strategy (160, 47.2%) or concomitant strategy (179, 52.8%) were retrospectively analyzed. Contrast‐induced acute kidney injury (CI‐AKI) occurred in 49 patients in the staged strategy group (30.6%) and in 18 patients (10.1%) in the concomitant strategy group (P<0.001). Among the staged strategy group, 25 (15.6%) patients developed CI‐AKI after coronary angiography or percutaneous coronary intervention, 17 (10.6%) after TAVI, and 7 (4.3%) after both the procedures. Staged strategy was associated with a higher risk of CI‐AKI (odds ratio, 3.948; P<0.001) after adjustment for multiple confounders and regardless of the baseline renal function (P for interaction=0.4) when compared with the concomitant strategy. At a median follow‐up of 24.0 months (3.0–35.3), CI‐AKI was not associated with sustained renal injury (P=0.794), irrespective of the adopted strategy. The concomitant strategy did not impact the overall early safety at 30 days follow‐up after TAVI compared to the staged strategy (P=0.609).

Conclusions

Performing coronary procedures with a staged strategy before TAVI was associated with a higher risk of CI‐AKI compared with a concomitant strategy. Moreover, a concomitant strategy did not increase the risk of procedure‐related complications.

Urinary Dickkopf-3 and Contrast-Associated Kidney Damage

BACKGROUND

Administration of iodinated contrast medium (CM) during invasive cardiovascular procedures may be associated with impairment of kidney function.

OBJECTIVES

Urinary dickkopf-3 (DKK3), a stress-induced renal tubular epithelium-derived glycoprotein, has been identified as a biomarker predicting both acute kidney injury (AKI) and persistent kidney dysfunction.

METHODS

Urinary DKK3/creatinine ratio (uDKK3/uCr), urine and serum neutrophil gelatinase-associated lipocalin (uNGAL, sNGAL) and serum cystatin C (sCyC) were assessed in 458 patients with chronic kidney disease scheduled for invasive cardiovascular procedures requiring CM administration with universal adoption of nephroprotective interventions. Contrast-associated AKI (CA-AKI) was defined as serum creatinine increase ≥0.3 mg/dl at 48 h after CM administration. Persistent kidney dysfunction was defined as persistent estimated glomerular filtration rate reduction ≥25% at 1 month compared with baseline.

RESULTS

CA-AKI occurred in 64 or the 458 patients (14%), and baseline uDKK3/uCr ≥491 pg/mg was the best threshold for its prediction. Net reclassification improvement (NRI) was significantly increased by adding baseline uDKK3/uCr to the Mehran, Gurm, and National Cardiovascular Data Registry (NCDR) scores (all p < 0.05), and the same applied to integrated discrimination improvement (IDI) when adding uDKK3/uCr to the Gurm and NCDR scores (p < 0.001). Persistent kidney dysfunction occurred in 57 of the 458 patients (12%) and baseline uDKK3/uCr ≥322 pg/mg appeared as the best threshold for its prediction. Adding baseline uDKK3/uCr to the Mehran, Gurm, and NCDR scores significantly increased IDI and NRI (all p < 0.001).

CONCLUSIONS

Baseline uDKK3/uCr seems to be a reliable marker for improving the identification of patients with chronic kidney disease undergoing invasive coronary and peripheral procedures at risk for AKI and persistent kidney dysfunction.

Potential Utility of Cardiorenal Biomarkers for Prediction and Prognostication of Worsening Renal Function in Acute Heart Failure

BACKGROUND

Multiple different pathophysiologic processes can contribute to worsening renal function (WRF) in acute heart failure.

METHODS AND RESULTS

We retrospectively analyzed 787 patients with acute heart failure for the relationship between changes in serum creatinine and biomarkers including brain natriuretic peptide, high sensitivity cardiac troponin I, galectin 3, serum neutrophil gelatinase-associated lipocalin, and urine neutrophil gelatinase-associated lipocalin. WRF was defined as an increase of greater than or equal to 0.3 mg/dL or 50% in creatinine within first 5 days of hospitalization. WRF was observed in 25% of patients. Changes in biomarkers and creatinine were poorly correlated (r ≤ 0.21) and no biomarker predicted WRF better than creatinine. In the multivariable Cox analysis, brain natriuretic peptide and high sensitivity cardiac troponin I, but not WRF, were significantly associated with the 1-year composite of death or heart failure hospitalization. WRF with an increasing urine neutrophil gelatinase-associated lipocalin predicted an increased risk of heart failure hospitalization.

CONCLUSIONS

Biomarkers were not able to predict WRF better than creatinine. The 1-year outcomes were associated with biomarkers of cardiac stress and injury but not with WRF, whereas a kidney injury biomarker may prognosticate WRF for heart failure hospitalization.

Biochemical Markers in the Prediction of Contrast-induced Acute Kidney Injury

For many years clinicians have been searching for "kidney troponin"- a simple diagnostic tool to assess the risk of acute kidney injury (AKI). Recently, the rise in the variety of contrast-related procedures (contrast computed tomography (CT), percutaneous coronary intervention (PCI) and angiography) has resulted in the increased number of contrast-induced acute kidney injuries (CI-AKI). CIAKI remains an important cause of overall mortality, prolonged hospitalisation and it increases the total costs of therapy. The consequences of kidney dysfunction affect the quality of life and they may lead to disability as well. Despite extensive worldwide research, there are no sensitive and reliable methods of CI-AKI prediction. Kidney Injury Molecule 1 (KIM-1) and Neutrophil Gelatinase Lipocalin (NGAL) have been considered as kidney-specific molecules. High concentrations of these substances before the implementation of contrast-related procedures have been suggested to enable the estimation of kidney vulnerability to CI-AKI and they seem to have the predictive potential for cardiovascular events and overall mortality. According to other authors, routine determination of known inflammation factors (e.g., CRP, WBC, and neutrophil count) may be helpful in the prediction of CIAKI. However, the results of clinical trials provide contrasting results. The pathomechanism of contrast- induced nephropathy remains unclear. Due to its prevalence, the evaluation of the risk of acute kidney injury remains a serious problem to be solved. This paper reviews pathophysiology and suggested optimal markers facilitating the prediction of contrast-induced acute kidney injury.

Renal impairment assessment on adults living nearby a landfill: Early kidney dysfunction biomarkers linked to the environmental exposure to heavy metals

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Health risk of the neighboring population of the Mbeubeuss landfill (Senegal).

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Assessment of the impact of Cd/Pb exposure through dysfunction renal biomarkers.

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Specific increases of a set of early dysfunction renal biomarkers in exposed subjects.

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Glomerular and tubular dysfunction in exposed subjects.

The aim of this study was to assess the integrity and kidney overall functional capacity of subjects exposed to landfill emissions. Urine and blood levels of Pb and Cd, and several of the newly biomarkers of nephrotoxicity (Kim Injury Molecule 1 (KIM-1), alpha-1 Microglobulin (α1 M), beta-2 Microglobulin (β2 M), Cystatin-C (Cyst C), Clusterin, alpha-glutathione S-transferase (GSTα), pi-glutathione S-transferase (GSTπ), Tissue Inhibitor of Metalloproteinase-1 (TIMP1), Calbindin, Neutrophil Gelatinase-Associated Lipocalin (NGAL), Osteopontin (OPN), (Retinol Binding Protein(RBP), Liver-type Fatty Acid-Binding Protein (FABP-1), Trefoil Factor 3 (TFF3), Collagen VI) were measured in order to assess glomerular and tubule damage in adults living near a landfill.

Our results indicate glomerular dysfunction in exposed subjects, and supported evidence of necrosis of proximal and distal tubule epithelial cells as specific biomarkers began to appear in the urine.

Positive correlation by Pearson test were obtained between : blood Pb and B-OPN, B-Cyst C, Calbindin, U-KIM-1, TIMP1, U-OPN, and U-Clusterin; and also, between urinary Cd and TIMP1, B-Clusterin, U-OPN, FABP-1, Albumin, and U-Clusterin. The relation between biomarkers of Cd/Pb exposure and early effect biomarkers in this study clearly predicts the future risk of severe kidney injury in subjects living close to the landfill.

Serum NGAL, KIM-1, IL-18, L-FABP: new biomarkers in the diagnostics of acute kidney injury (AKI) following invasive cardiology procedures

PURPOSE

The aim of this study was to assess the levels of selected markers in patients who underwent planned or emergency coronary angiography and to examine if they correlated with the occurrence of AKI.

METHODS

The study included 52 patients who underwent planned or emergency coronary angiography and received contrast agent. Serum levels of markers (NGAL, L-FABP, KIM-1, IL-18) were analyzed in all patients using ELISA tests, at baseline, after 24 and 72 h from angiography.

RESULTS

9.62% of patients developed CI-AKI. No significant differences were observed between markers levels in patients who developed CI-AKI and those who did not. After 24 h, serum levels of IL-18 were higher in patients with CI-AKI, however, this difference was on the verge of significance. Increase in serum NGAL, KIM-1 and IL-18 was observed after 24 h. Serum levels of biomarkers were insignificantly higher in group with CI-AKI. Significant changes in levels in time (baseline vs. 24 h vs. 72 h) were observed only for NGAL [157.9 (92.4-221.0) vs. 201.8 (156.5-299.9) vs. 118.5 (73.4-198.7); p < 0.0001]. No significant correlations were observed between the decrease in eGFR or the increase in creatinine and biomarkers level.

CONCLUSION

Obtained results do not allow for the indication of efficient AKI biomarkers. Their further validation in large studies of CI-AKI patients is required.

Hydration: Intravenous and Oral: Approaches, Principals, and Differing Regimens: Is It What Goes in or What Comes Out That Is Important?

The literature (in English) was accessed to review the evidence that administration of fluids is protective of contrast-associated acute kidney injury (CA-AKI). The evidence was evaluated with the intent of understanding mechanisms of protection. Prospective randomized trials comparing oral versus intravenous fluid, sodium chloride versus no intravenous fluid, sodium bicarbonate versus sodium chloride, and forced matched hydration versus intravenous sodium chloride provided the data. In general, the more fluid administered, the lower the incidence of CA-AKI. However, understanding the mechanism of this beneficial effect suggests that it is the urine output that most directly affects the incidence of CA-AKI.

Contrast-Induced Acute Kidney Injury-Definitions, Epidemiology, and Implications

Contrast-induced acute kidney injury (CI-AKI) is the acute onset of renal injury following exposure to iodinated contrast media. Several definitions have been used, which complicates the estimation of the epidemiological relevance of this condition and comparisons in outcome research. The incidence of CI-AKI increases as a function of patient and procedure complexity in coronary, endovascular, and structural interventions. CI-AKI is associated with a high burden of short- and long-term adverse events, and leads to increased healthcare costs. This review will provide an overview of the definitions, epidemiology, and implications of CI-AKI in patients undergoing coronary, endovascular, and structural catheter-based procedures.

Predictive value of cystatin C and neutrophil gelatinase-associated lipocalin in contrast-induced nephropathy: A meta-analysis

Background

There are still limited studies comprehensively examining the diagnostic performance of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C in contrast-induced nephropathy (CIN). The study aimed to investigate and compare the predictive value of NGAL and cystatin C in the early diagnosis of CIN.

Methods and materials

We searched the PubMed, EMBASE and Cochrane Library databases until November 10, 2019. The methodological quality of the included studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Bivariate modeling and hierarchical summary receiver operating characteristic (HSROC) modeling were performed to summarize and compare the diagnostic performance of blood/urine NGAL and serum cystatin C in CIN. Subgroup and meta-regression analyses were performed according to the study and patient characteristics.

Results

Thirty-seven studies from thirty-one original studies were included (blood NGAL, 1840 patients in 9 studies; urine NGAL, 1701 patients in 10 studies; serum cystatin C, 5509 patients in 18 studies). Overall, serum cystatin C performed better than serum/urine NGAL (pooled DOR: 43 (95%CI: 12–152); AUROC: 0.93; λ: 3.79); serum and urine NGAL had a similar diagnostic performance (pooled DOR: 25 (95%CI: 6–108)/22(95%CI: 8–64); AUROC: 0.90/0.89; λ: 3.20/3.08). Meta-regression analysis indicated that the sources of heterogeneity might be CIN definition, assays, and nationalities.

Conclusion

Both NGAL and cystatin C can serve as early diagnostic indicators of CIN, while cystatin C may perform better than NGAL.

Role of serum cystatin C in the prediction of contrast-induced nephropathy after intra-arterial interventions

Background

The diagnosis of contrast-induced nephropathy (CIN) is usually based on changes in serum creatinine (sCr). However, sCr has poor sensitivity as a biomarker of kidney injury. The aim of this study was to investigate the usefulness of serum cystatin C (sCysC) to predict CIN after intra-arterial interventions.

Methods

A total of 360 consecutive patients underwent intra-arterial procedures using digital subtraction angiography. SCr, sCysC, and estimated glomerular filtration rate were measured at 1 to 2 days before and at 48, 72 h, and 7 days after the procedure.

Results

Thirty-one patients (8.61%) developed CIN. Receiver operating characteristic (ROC) curve analysis showed that pre-operative sCysC levels had good discriminatory power (area under the curve [AUC] = 0.634; 95% confidence interval [CI] = 0.526–0.743) for evaluating the risk of CIN after an endovascular procedure, with a sensitivity of 53.33% and specificity of 73.70%. ROC analysis showed that sCysC at 48 h after contrast medium administration was predictive of CIN after an endovascular procedure (AUC = 0.735; 95% CI = 0.647–0.822) with satisfactory sensitivity of 74.20% and specificity of 63.90%. Diabetes mellitus was an independent risk factor for CIN (odds ratio = 2.778; 95% CI = 1.045–7.382; P = 0.040).

Conclusions

SCysC is an appropriate biomarker to predict the occurrence of CIN. Baseline sCysC before an intervention is useful to obtain a preliminary estimate of the risk of CIN. A 48-h cut-off value of sCysC of 0.99 mg/L after an endovascular procedure may help to rule out patients at lower risk of CIN.

Biomarkers for Diagnosis and Prediction of Outcomes in Contrast-Induced Nephropathy

Background

Serum creatinine is suboptimal as a biomarker in the early diagnosis of contrast-induced nephropathy (CIN). In this study, we investigated a panel of novel biomarkers in the early diagnosis of CIN and in assessing patient outcomes.

Methods

This single-centre, nested, prospective case-controlled study included 30 patients with CIN and 60 matched controls. Serum and urine samples were collected before contrast administration and at 24 hours, 48 hours, and ≥5 days after contrast administration. Concentrations of NGAL, cystatin C, β₂M, IL18, IL10, KIM1, and TNFα were determined using Luminex and ELISA assays. Outcomes were biomarker diagnostic discrimination performance for CIN and mortality after generation of area under receiver operating characteristic curves (AUROCs).

Results

Median serum levels for 24 h cystatin C (p < 0.01) and 48 h β₂M levels (p < 0.001) and baseline urine NGAL (p=0.02) were higher in CIN patients compared to controls with AUROCs of 0.75, 0.78, and 0.74, respectively, for the early diagnosis of CIN. Serum β₂M levels were higher in CIN patients at all time points. Elevated baseline serum concentrations of IL18 (p < 0.001), β₂M (p=0.04), TNFα (p < 0.001), and baseline urine KIM (p=0.01) and 24 h urine NGAL (p=0.02) were significantly associated with mortality. Baseline serum concentrations of IL18, β₂M, and TNFα showed the best discrimination performance for mortality with AUROCs, all >0.80. Baseline NGAL was superior for excluding patients at risk for CIN, with positive and negative predictive ranges of 0.50–0.55 and 0.81–0.88, respectively. Cystatin C (p=0.003) and β₂M (p=0.03) at 24 h independently predicted CIN risk. β₂M predicted increased mortality of 40% at baseline and 50% at 24 hours.

Conclusion

Serum cystatin C at 24 h was the best biomarker for CIN diagnosis, while baseline levels of serum IL18, β₂M, and TNFα were best for predicting prognosis.

Evaluation of neutrophil gelatinase-associated lipocalin and cystatin C as biomarkers of acute kidney injury after ST-segment elevation myocardial infarction treated by percutaneous coronary intervention

BACKGROUND

Two biomarkers of early acute kidney injury-plasmatic neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C-are not used in routine clinical practice in patients with ST-segment elevation myocardial infarction (STEMI) treated by percutaneous coronary intervention (PCI) because of a lack of supporting data.

AIMS

To evaluate the predictive value of NGAL and cystatin C regarding the incidence of contrast-induced acute kidney injury (CI-AKI) and clinical outcomes after STEMI in patients treated by primary PCI.

METHODS

Plasmatic NGAL and cystatin C were measured on admission, before any contrast exposure, in 701 unselected patients with STEMI. Associations between biomarker concentrations and incidence of CI-AKI (assessed at 48h), haemodialysis requirement at 1 year and all-cause mortality at 1 year were assessed by logistic regression analyses and receiver operating characteristic area under the curve analysis (c-statistic). Discrimination performance comparison was performed using the DeLong test.

RESULTS

NGAL and cystatin C had mild discrimination regarding CI-AKI, with c-statistics of 0.60 (P=0.001) and 0.60 (P=0.002), respectively. Combining NGAL and cystatin C did not improve their discrimination (c-statistic 0.61; P=0.001). There was no significant difference in discrimination between NGAL, cystatin C and baseline creatinine (P=0.57). Regression analyses showed no independent association between NGAL and CI-AKI, haemodialysis or 1-year mortality. Similarly, cystatin C was not associated with these clinical outcomes.

CONCLUSIONS

In this cohort of patients with STEMI treated by primary PCI, plasmatic NGAL and cystatin C did not provide additional value regarding CI-AKI prediction compared with known risk factors such as baseline creatinine.

Serum NGAL and FGF23 may have certain value in early diagnosis of CIN

Aims: This study aimed to assess whether neutrophil gelatinase-associated lipocalin (NGAL) and fibroblast growth factor 23 (FGF23) could be reliable biomarkers for early diagnosis of contrast-induced nephropathy (CIN).

Methods: 202 patients who underwent percutaneous coronary intervention (PCI) were included in the research. All subjects were divided into CIN group and non-CIN group. Serum NGAL and FGF23 were evaluated before and 0, 1, and 2 days after PCI. Serum levels of these two markers were compared intra-group and among groups. Receiver-operating characteristic (ROC) analysis and logistic regression models were conducted to assess the diagnostic performance of NGAL and FGF23 in detecting CIN.

Results: When compared with baseline values, serum levels of both NGAL and FGF23 in all subjects increased after PCI, and the values peaked 1 day after PCI, but the changing was greater in CIN group. There were obvious differences between two groups in serum NGAL after 1, 2 days, and similar differences present in serum FGF23 after 1 day. ROC analysis showed that the area under the curve (AUC) of relative values (percent change from the baseline) in NGAL after 1 day was 0.899 (95% CI: 0.834–0.964, p = .000), the optimum cutoff was 49% (sensitivity = 80%, specificity = 92.4%). And the AUC in FGF23 was 0.814 (95% CI: 0.733–0.894, p = .000), the optimum cutoff was 20% (sensitivity = 73.3%, specificity = 87.6%). Both serum NGAL and serum FGF23 could improve the clinical models in identifying CIN.

Conclusions: NGAL and FGF23 may have certain value in early diagnosis of CIN.

Early prediction of contrast-induced acute kidney injury by a "bedside" assessment of Neutrophil Gelatinase-Associated Lipocalin during elective percutaneous coronary interventions

Contrast-induced acute kidney injury (CI-AKI) is a serious complication during percutaneous coronary interventions (PCI). Currently, the diagnosis of CI-AKI relies on serum creatinine (SCr) that is however affected by several limitations potentially leading to delayed or missed diagnoses. In this study we examined the diagnostic accuracy of a “bedside” measurement of plasma Neutrophil Gelatinase-Associated Lipocalin (NGAL) in the early detection of CI-AKI in 97 patients undergoing elective PCI. The overall incidence of CI-AKI was 3%. A significant positive correlation was observed between 6-hours NGAL and post-PCI SCr (r = 0.339, p = 0.004) and a significant negative correlation between 6-hours NGAL and post-PCI CrCl (r = -0.303, p = 0.010). In patients with post-PCI SCr increase > 0.24 mg/dl (median SCr absolute increase), delta NGAL 0–6 hours and 6-hours NGAL values were higher compared with patients with SCr elevation below the defined threshold (p = 0.049 and p = 0.056). The ROC analysis showed that a 6 hours NGAL value > 96 ng/ml significantly predicted an absolute SCr increase > 0.24 mg/dl after contrast exposure with sensitivity of 53% and specificity of 74% (AUC 0.819, 95% CI: 0.656 to 0.983, p = 0.005). The use of bedside NGAL assessment may significantly hasten diagnosis and treatment of CI-AKI, with remarkable clinical prognostic consequences.

Prediction of contrast induced acute kidney injury using novel biomarkers following contrast coronary angiography

BACKGROUND/INTRODUCTION

Chronic kidney disease (CKD) is a risk factor for contrast induced acute kidney injury (CI-AKI). Contrast angiography in CKD patients is a common procedure. Creatinine is a delayed marker of CI-AKI and delays diagnosis which results in significant morbidity and mortality.

AIM

Early diagnosis of CI-AKI requires validated novel biomarkers.

DESIGN

A prospective observation study of 301 consecutive CKD patients undergoing coronary angiography was performed.

METHODS

Samples for plasma neutrophil gelatinase-associated lipocalin (NGAL), serum liver fatty acid-binding protein (L-FABP), serum kidney injury marker 1, serum interleukin 18 and serum creatinine were taken at 0, 1, 2, 4, 6 and 48 h post-contrast. Urinary NGAL and urinary cystatin C were collected at 0, 6 and 48 h. Incidence of major adverse clinical events (MACE) was recorded at 1 year. CI-AKI was defined as an absolute delta rise in creatinine of ≥26.5 µmol/l or a 50% relative rise from baseline at 48 h following contrast.

RESULTS

CI-AKI occurred in 28 (9.3%) patients. Plasma NGAL was most predictive of CI-AKI at 6 h. L-FABP performed best at 4 h. A combination of Mehran score > 10, 4 h L-FABP and 6 h NGAL improved specificity to 96.7%. MACE was statistically higher at 1 year in CI-AKI patients (25.0 vs. 6.2% in non-CI-AKI patients).

DISCUSSION/CONCLUSION

Mehran risk score, 4 h serum L-FAPB and 6 h plasma NGAL performed best at early CI-AKI prediction. CI-AKI patients were four times more likely to develop MACE and had a trebling of mortality risk at 1 year.

Contrast media-induced nephropathy: how has Italy contributed in the past 30 years? A systematic review

Background and objective

The use of contrast media in Italy has exponentially increased in the past 3 decades. However, it is unknown whether there has been an increase in clinical research evaluating the risks associated with contrast media usage, especially regarding contrast-induced nephropathy. To fill this gap in knowledge, we performed a systematic review.

Study eligibility criteria

Meta-analyses, observational studies, and clinical trials assessing contrast media-induced nephropathy as the safety outcome, in which at least one author was affiliated with an Italian university/health care structure, were eligble.

Data sources

Ovid MEDLINE, Ovid Embase, Cochrane Methodology Register, and Web of Science were screened.

Participants

Men and women exposed to contrast media.

Results

In total, 60 original articles were retrieved with an incremental trend between 1990 and 2017. Cohort studies were the most common study design represented. In total, 45 of 60 (75.0%) studies were monocenter studies and 41 of 60 (68.3%) received no funding. In all, 91.7% of studies disclosed no conflicts of interest and 81.7% had no external collaboration. Most of the studies provided a level of evidence of III-2 (32/60; 53.3%) and II (23/60; 38.3%). In total, 50 of 60 studies (83.3%) were published in a scientific journal ranked in the first quartile of their subject area.

Conclusion

There was an increased number of studies evaluating contrast-induced nephropathy in Italy during the last three decades. These studies covered procedures to prevent contrast-induced nephropathy or aimed to identify risk factors, biomarkers, and scores, and their related prognosis.

Neutrophil Gelatinase-Associated Lipocalin for Acute Kidney Injury During Acute Heart Failure Hospitalizations: The AKINESIS Study

BACKGROUND

Worsening renal function (WRF) often occurs during acute heart failure (AHF) and can portend adverse outcomes; therefore, early identification may help mitigate risk. Neutrophil gelatinase-associated lipocalin (NGAL) is a novel renal biomarker that may predict WRF in certain disorders, but its value in AHF is unknown.

OBJECTIVES

This study sought to determine whether NGAL is superior to creatinine for prediction and/or prognosis of WRF in hospitalized patients with AHF treated with intravenous diuretic agents.

METHODS

This was a multicenter, prospective cohort study enrolling patients presenting with AHF requiring intravenous diuretic agents. The primary outcome was whether plasma NGAL could predict the development of WRF, defined as a sustained increase in plasma creatinine of 0.5 mg/dl or ≥50% above first value or initiation of acute renal-replacement therapy, within the first 5 days of hospitalization. The main secondary outcome was in-hospital adverse events.

RESULTS

We enrolled 927 subjects (mean age, 68.5 years; 62% men). The primary outcome occurred in 72 subjects (7.8%). Peak NGAL was more predictive than the first NGAL, but neither added significant diagnostic utility over the first creatinine (areas under the curve: 0.656, 0.647, and 0.652, respectively). There were 235 adverse events in 144 subjects. The first NGAL was a better predictor than peak NGAL, but similar to the first creatinine (areas under the curve: 0.691, 0.653, and 0.686, respectively). In a post hoc analysis of subjects with an estimated glomerular filtration rate <60 ml/min/1.73 m(2), a first NGAL <150 ng/ml indicated a low likelihood of adverse events.

CONCLUSIONS

Plasma NGAL was not superior to creatinine for the prediction of WRF or adverse in-hospital outcomes. The use of plasma NGAL to diagnose acute kidney injury in AHF cannot be recommended at this time. (Acute Kidney Injury Neutrophil Gelatinase-Associated Lipocalin [N-GAL] Evaluation of Symptomatic Heart Failure Study [AKINESIS]; NCT01291836).

Serum neutrophil gelatinase-associated lipocalin has an advantage over serum cystatin C and glomerular filtration rate in prediction of adverse cardiovascular outcome in patients with ST-segment elevation myocardial infarction

Background

The aim of this study was to assess significance of serum neutrophil gelatinase-associated lipocalin (sNGAL) and cystatin C (sCC) in prediction of adverse cardiovascular outcome after ST-segment elevation myocardial infarction (STEMI).

Methods

We recruited 357 consecutive patients who were admitted to the hospital within 24 h after onset of STEMI. On the 1st and 12th-14th day after hospital admission, we measured levels of sNGAL and sCC. We also determined presence of renal dysfunction (RD), defined as glomerular filtration rate < 60 mL/min/1.73 m². After 3 years of follow-up, we performed a logistic regression and assessed the value of RD, sNGAL, and sCC in prediction of combined endpoint, defined as cardiovascular death or any cardiovascular complication.

Results

RD, sCC level ≥ 1.9 mg/L, and sNGAL level ≥ 1.25 ng/mL on the 12th-14th day of hospitalization were associated with a 1.6-fold, 1.9-fold, and 2.9-fold higher risk of adverse cardiovascular outcome, respectively. Area under the ROC curve was the highest for the model based on sNGAL level compared to the models based on sCC level or RD presence.

Conclusions

Measurement of sNGAL level in patients with STEMI on the 12th-14th day after hospital admission may improve prediction of adverse cardiovascular outcome.

Neutrophil gelatinase-associated lipocalin (NGAL) fails as an early predictor of contrast induced nephropathy in chronic kidney disease (ANTI-CI-AKI study)

The aim of the study was to evaluate the diagnostic accuracy of urinary neutrophil gelatinase- associated lipocalin (uNGAL) in patients with chronic kidney disease (CKD) as an early biomarker for contrast induced acute kidney injury (CI-AKI) and to investigate whether patients with an uNGAL increase might benefit from an additional intravenous volume expansion with regard to CI-AKI-incidence. We performed a prospective randomized controlled trial in 617 CKD-patients undergoing intra-arterial angiography. Urinary NGAL was measured the day before and 4-6hrs after angiography. In the event of a significant rise of uNGAL patients were randomized either into Group A, who received intravenous saline post procedure or Group B, who did not receive post-procedural i.v. fluids. Ten patients (1.62%) exhibited a significant rise of uNGAL after angiography and were randomized of whom one developed a CI-AKI. In the entire cohort the incidence of CI-AKI was 9.4% (58 patients) resulting in a specificity of 98.4% (95% CI: 97.0-99.3%) and a sensitivity of 1.72% (95% CI: 0.044-9.2%) of uNGAL for the diagnosis of CI-AKI. In this study uNGAL failed to predict CI-AKI and was an inadequate triage tool to guide an early intervention strategy to prevent CI-AKI.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01292317.

Comparison of Effects of Different Statins on Contrast-Induced Acute Kidney Injury in Rats: Histopathological and Biochemical Findings

Statins are a promising new strategy to prevent contrast-induced acute kidney injury (CI-AKI). In this study we compared the ameliorative effect of different statins in a rat model of CI-AKI. Sprague-Dawley rats were divided into five groups: control group; CI-AKI group; CI-AKI + rosuvastatin group (10 mg/kg/day); CI-AKI + simvastatin group (80 mg/kg/day); and CI-AKI + atorvastatin group (20 mg/kg/day). CI-AKI was induced by dehydration for 72 hours, followed by furosemide intramuscular injection 20 minutes before low-osmolar contrast media (CM) intravenous injection. Statins were administered by oral gavage once daily for 3 consecutive days before CM injection and once 4 hours after CM injection. Rats were sacrificed 24 hours after CM injection, and renal function, kidney histopathology, nitric oxide (NO) metabolites, and markers of oxidative stress, inflammation, and apoptosis were evaluated. The results showed that atorvastatin and rosuvastatin but not simvastatin ameliorated CM-induced serum creatinine elevation and histopathological alterations. Atorvastatin and rosuvastatin showed similar effectiveness against CM-induced oxidative stress, but simvastatin was less effective. Atorvastatin was most effective against NO system dysfunction and cell apoptosis, whereas rosuvastatin was most effective against inflammation. Our findings indicate that statins exhibit differential effects in preventing CI-AKI when given at equivalent lipid-lowering doses.