The role of neutrophil-gelatinase-associated lipocalin in early diagnosis of contrast nephropathy

Biomarker-Guided Assessment of Acute Kidney Injury Phenotypes E among ST-Segment Elevation Myocardial Infarction Patients

Recent practice guidelines recommended the use of new stress, functional, and damage biomarkers in clinical practice to prevent and manage acute kidney injury (AKI). Biomarkers are one of the tools used to define various AKI phenotypes and provide prognostic information regardless of an acute decline in renal function. We investigated the incidence and possible implications of AKI phenotypes among ST elevation myocardial infarction patient treated with primary coronary intervention. We included 281 patients with STEMI treated with PCI. Neutrophil gelatinase associated lipocalin (NGAL) was utilized to determine structural renal damage and functional AKI was determined using the KDIGO criteria. Patients were stratified into four AKI phenotypes: no AKI, subclinical AKI, hemodynamic AKI, and severe AKI. Patients were assessed for in-hospital adverse events (MACE). A total of 46 patients (44%) had subclinical AKI, 17 (16%) had hemodynamic AKI, and 42 (40%) had severe AKI. We observed a gradual and significant increase in the occurrence of MACE between the groups being highest among patients with severe AKI (10% vs. 19% vs. 29% vs. 43%; p < 0.001). In a multivariable regression model, any AKI phenotype was independently associated with MACE with an odds ratio of 4.15 (95% CI 2.1−8.3, p < 0.001,) for subclinical AKI, 4.51 (95% CI 1.61−12.69; p = 0.004) for hemodynamic AKI, and 12.9 (95% CI 5.59−30.1, p < 0.001) for severe AKI. In conclusion, among STEMI patients, AKI is a heterogeneous condition consisting of distinct phenotypes, addition of novel biomarkers may overcome the limitations of sCr-based AKI definitions to improve AKI phenotyping and direct potential therapies.

Biomarkers for the early prediction of contrast-induced nephropathy after percutaneous coronary intervention in adults: A systematic review and meta-analysis

Contrast-induced nephropathy (CIN) is a complication of patients undergoing percutaneous coronary intervention (PCI). Promising biomarkers for the early prediction of CIN can significantly improve outcomes of these patients. We searched PubMed, EMBASE, Web of Science, and Cochrane Library for studies. Trials reporting an area under the curve (AUC) for the utility of novel biomarkers in the early prediction of CIN in adults after PCI were included. In total, 42 studies comprising 11,984 adult patients undergoing PCI met the criteria. Four urinary biomarkers and four blood biomarkers were included. For urine biomarkers, the pooled AUCs for neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18), liver-type fatty acid-binding protein (L-FABP), and kidney injury molecule-1 (KIM-1) were 0.91 (95% CI 0.89-0.94), 0.79 (0.75-0.82), 0.78 (0.74-0.82), and 0.79 (0.76-0.83), respectively. The blood biomarkers NGAL, cystatin C, brain natriuretic peptide (BNP), and C-reactive protein (CRP) had pooled AUCs of 0.93 (0.91-0.95), 0.92 (0.89-0.94), 0.78 (0.74-0.81), and 0.75 (0.71-0.79), respectively. Subgroup analysis showed that blood NGAL in early CIN predictive time (<6 h) was more effective in predicting CIN. The efficiency of cystatin C in predicting CIN was reduced, whereas that of L-FABP was increased among chronic kidney disease (CKD) patients.

Detection of Renal Injury Following Primary Coronary Intervention among ST-Segment Elevation Myocardial Infarction Patients: Doubling the Incidence Using Neutrophil Gelatinase-Associated Lipocalin as a Renal Biomarker

Background: A subgroup of patients with acute kidney injury (AKI) do not fulfil the functional criteria for AKI diagnosis but show elevated levels of new biomarkers reflecting tubular injury, suggesting that these patients suffer “subclinical AKI”. We investigated the incidence and possible implications of “subclinical AKI”, compared to no and clinical AKI among ST elevation myocardial infarction patients (STEMI) treated with primary coronary intervention (PCI). Methods: We included 223 patients with STEMI treated with PCI. Neutrophil gelatinase-associated lipocalin (NGAL) was used as a marker of renal tubular damage in the absence of functional AKI, with NGAL levels ≥100 ng/mL suggesting subclinical AKI. Patients were assessed for the occurrence of in-hospital adverse outcomes. Results: Of the study patients, 45 (25%) had subclinical AKI. These patients were more likely to have left ventricular ejection fraction ≤45% (33% vs. 23%. p = 0.01), in-hospital adverse outcomes (73% vs. 48%; p = 0.005), and a combination of the two. The multivariate regression model demonstrated that subclinical AKI was independently associated with in-hospital adverse outcomes (OR 3.71, 95% CI 1.30–10.62, p = 0.02). Conclusions: Subclinical AKI is common among STEMI patients and is independently associated with adverse outcomes, even in the absence of functional AKI.

Neutrophil Gelatinase-Associated Lipocalin for the Assessment of Reversible versus Persistent Renal Tubular Damage in ST-Segment Myocardial Infarction Patients

BACKGROUND

Most studies investigated the value of neutrophil gelatinase-associated lipocalin (NGAL) as a marker of renal tubular injury only at a single time point. We investigated the possible utilization of NGAL level dynamics for the identification of different renal injury patterns in ST-elevation myocardial infarction (STEMI) patients.

METHODS

Blood samples for plasma NGAL in 132 STEMI patients were drawn immediately before and 24 h following primary coronary intervention. Abnormal elevation of NGAL levels was defined using the cardiac surgery-associated NGAL score with NGAL levels ≥100 ng/mL suggesting renal tubular damage. According to NGAL levels at 0 and 24 h, patients were stratified into 3 groups: no tubular damage (NGAL <100 ng/mL in both exams), reversible tubular damage (NGAL >100 ng/mL at 0 h but <100 ng/mL at 24 h), and persistent tubular damage (NGAL >100 ng/mL at both 0 and 24 h).

RESULTS

Mean age was 62 ± 13 years, and 78% were men. Of these patients, 29/132 (22%) demonstrated reversible tubular damage, and 36/132 (27%) persistent tubular damage. Only 13/132 patients (10%) progressed to clinical acute kidney injury during hospitalization, all of whom had persistent tubular injury. In multivariate regression model, symptom duration was independently associated with persistent tubular damage, both as continues variable (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.01-1.04; p = 0.04) and for symptom duration >360 min (OR 2.66, 95% CI 1.07-6.63; p = 0.03).

CONCLUSIONS

Renal tubular damage is common among STEMI patients. Dynamic NGAL measurement may differentiate between reversible and persistent tubular damage. Further trials are needed in order to assess the complex cardiorenal interactions.

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.

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.

Elevated neutrophil gelatinase-associated lipocalin levels before contrast media administration among ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention

BACKGROUND

Neutrophil gelatinase-associated lipocalin (NGAL) is a glycoprotein released by renal tubular cells upon nephrotoxic or ischemic events and is considered an early marker of tubular damage. We aimed to demonstrate the presence of early renal injury detected by elevated NGAL levels taken before contrast administration in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

We prospectively included 88 patients with STEMI treated with PCI. Blood samples for plasma NGAL were drawn immediately before PCI (baseline NGAL; NGAL1) and 24 h after PCI (NGAL2). Abnormal elevations in NGAL levels were defined using the cardiac surgery associated NGAL score (NGAL score) with NGAL levels at least 100 ng/ml, suggesting renal tubular damage. Patients were also assessed for the dynamics between NGAL2 and NGAL1 levels.

RESULTS

The mean age of the patients was 62 ± 13 years and 78% were men. A total of 50/88 (56%) patients had baseline NGAL level of at least 100, suggesting possible tubular damage before PCI. Only 10 patients progressed to clinical acute kidney injury during hospitalization, all of whom had baseline NGAL level of at least 100 (P < 0.001). Among patients with baseline NGAL at least 100, 28/50 (56%) showed a decrease in the NGAL level within 24 h, whereas only 9/50 (18%) showed an elevation in the NGAL level. In contrast, only 7/38 (19%) patients with baseline NGAL level less than 100 showed an elevation in NGAL levels within 24 h.

CONCLUSION

Elevated NGAL levels before primary PCI suggesting renal tubular damage are common among STEMI patients. Further trials are needed to assess the complex cardio-renal interactions.

Serum Neutrophil Gelatinase-Associated Lipocalin and Urinary Kidney Injury Molecule-1 as Potential Biomarkers of Subclinical Nephrotoxicity After Gadolinium-Based and Iodinated-Based Contrast Media Exposure in Pediatric Patients with Normal Kidney Function

Background

New renal biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) show promise in early diagnosis of contrast media induced acute kidney injury (CI-AKI). The purpose of our study was to compare the subclinical nephrotoxicity (a condition without changes in standard renal biomarkers) of gadolinium-based contrast media (Gd-DTPA, gadopentetate dimeglumine) and iodinated-based contrast media (iopromide) in pediatric patients with normal kidney function.

Material/Methods

The first group (n=58) of patients included in the study were undergoing angiography with iopromide, and the second group (n=65) were undergoing magnetic resonance (MR) angiography/urography with Gd-DTPA administration. The concentrations of NGAL and KIM-1 were measured four times in the urine (pre-contrast, then at four hours, 24 hours, and 48 hours after contrast administration), and serum NGAL was measured at 0 (baseline), 24 hours, and 48 hours after contrast exposure.

Results

After 24 hours, serum NGAL increase of ≥25% was noticed in 32.6% of the patients in the iopromide group and in 25.45% of the patients in the gadolinium group, with significantly higher average percent of this increase in first group (62.23% vs. 36.44%, p=0.002). In the Gd-DTPA group, we observed a statistically significant increase in urinary KIM-1 24 hours after the procedure. Normalized urinary KIM-1, 24 hours after contrast exposure, was a better predictive factor for CI-AKI than other biomarkers (AUC 0.757, cut off 214 pg/mg, sensitivity 83.3%, specificity 54.2%, p=0.035).

Conclusions

In children with normal renal function, exposure to iodinated-based and gadolinium-based media might lead to subclinical nephrotoxicity, which could be detected using serum NGAL and urinary KIM-1.

Value of plasma neutrophil gelatinase-associated lipocalin (NGAL) in distinguishing between acute kidney injury (AKI) and chronic kidney disease (CKD)

OBJECTIVE

In this study, we aimed to determine whether plasma NGAL levels could be used as a biomarker for distinguishing between AKI and CKD in emergency medicine.

MATERIALS AND METHODS

This prospective study was conducted at the ED of a training and research hospital over a six-month period in 2015. Three groups were defined: an AKI group - defined as a new onset of at least a 1.5-fold or ≥0.3 mg increment increase of SCr values from the normal baseline, a stable CKD group - only included presence of stages 2 through 4 of CKD according to the National Kidney Foundation's KDIGO 2012, and a control group. After the initial evaluation of patients, venous blood samples were taken for routine biochemical, counter blood cell, and plasma NGAL measurement at admission.

RESULTS

A total of 25 patients with AKI, 22 patients with stable CKD, and 22 control subjects were enrolled. Level of plasma NGAL in AKI group was higher than those of the stable CKD group (median: 794 ng/ml IQR: 317-1300 & 390 ng/ml IQR: 219-664, p < 0.001). AUC was measured as 0.68 (p = 0.02, 95% CIs: 0.54-0.84) to assess the utility of plasma NGAL levels at varying cut-off values for distinguishing between AKI and CKD. For plasma NGAL, the best cut-off level was found to be 457 ng/ml (sensitivity: 72.0%, specificity: 64%).

CONCLUSION

This study has clearly demonstrated that plasma NGAL levels were higher in AKI patients than in CKD patients. However, in clinical practice, the use of plasma NGAL levels to distinguish between AKI and CKD is limited.