Urinary neutrophil gelatinase-associated lipocalin predicted to contrast-associated acute kidney injury after planned percutaneous coronary intervention in elderly patients.

AIM: To determine the proportion of contrast-associated acute kidney injury (CA-AKI) after percutaneous coronary intervention (PCI) and the predictive value of urine neutrophil gelatinase-associated lipocalin (uNGAL) for CA-AKI in elderly patients with chronic coronary artery disease. METHODS: A total of 509 patients who had planned percutaneous coronary intervention (mean age was 63.58 ± 11.63 years and 63.3% of males) were divided into two groups: group 1 (n = 153; elderly patients) with ≥70 years old and group 2 (n = 356) with <70 years old. Urine NGAL was measured by the ELISA method. Clinical and laboratory data were collected on the day before intervention. CA-AKI was defined based on Kidney Disease: Improving Global Outcomes criteria. RESULTS: The ratio of CA-AKI in group 1 was 23.5% which was higher than that of group 2 (8.7%) with a p-value < 0.001. Urine NGAL level in group 1 was significantly higher than that of group 2 [31.3 (19.16-55.13) ng/ml vs. 19.86 (13.21-29.04) ng/ml, p < 0.001]. At a cut-off value of 44.43 ng/ml, uNGAL had a predictive value for CA-AKI in all patients (AUC = 0.977, p < 0.001). Especially at a cut-off value of 44.14 ng/ml, uNGAL had a predictive value for CA-AKI in elderly patients (AUC = 0.979, p < 0.001). CONCLUSIONS: The rate of CA-AKI after PCI in elderly patients was 23.5%. Urine NGAL before PCI had a good predictive value for CA-AKI in elderly patients with chronic coronary artery disease.

Urine neutrophil gelatinase-associated lipocalin and urine output as predictors of the successful discontinuation of continuous renal replacement therapy in critically ill patients with acute kidney injury.

BACKGROUND: Continuous renal replacement therapy (CCRT) is a frequently used modality for the support of intensive care patients with acute kidney injury (AKI). Nevertheless, there are no objective criteria for the discontinuation of CRRT. The purpose of this study was to investigate whether urine neutrophil gelatinase-associated lipocalin (uNGAL) alone or in combination with urine output could be used as a diagnostic test for renal function recovery in ICU patients on CRRT. METHODS: This was a single-centre prospective observational study including patients with acute kidney failure needing CRRT. Sixty-nine patients were enrolled, and 54 completed the study. Of the 54 patients, 22 recovered renal function (REC), defined as dialysis independency at 72 h from discontinuation, while 32 patients did not (NREC). Urine NGAL was measured at 0, 6, 12, and 24 h after CRRT discontinuation. The cumulated urine output was measured for 24 h prior to discontinuation and at 6, 12, and 24 h after discontinuation. Missing uNGAL values were calculated by interpolation. The Youden's index was used to calculate cut-off values in order to define uNGAL and urine output single variable and 2-variable diagnostic tests with the optimum prediction of successful CRRT discontinuation. RESULTS: Baseline characteristics at CRRT initiation were similar between groups. Compared to the NREC group, the REC group had significantly higher urine output (p < 0.0001) and lower uNGAL (p < 0.001) at all time points, except for uNGAL at 24 h (p < 0.24). The best uNGAL predictor for successful CRRT discontinuation was uNGAL at 6 h after discontinuation (predictive value 80%). The best single predictor was cumulated urine output 24 h before discontinuation (predictive value 85%). The combinations of uNGAL at 6 h (cut-off 1650 µg/L) with cumulated urine output 24 h prior to discontinuation (cut-off 210 ml) proved to be the superior tests (using either "or" or "and"), with predictive values of 93% (successful CRRT discontinuation) and 92% (dialysis dependency). CONCLUSIONS: With a predictive value of 93%, the combination of uNGAL at 6 h after and the cumulated urine output 24 h prior to CRRT cessation proved to be the best diagnostic test for successful CRRT discontinuation in ICU patients. CLINICAL TRIAL REGISTRATION: N/A.

Early Diagnosis Of Acute Kidney Injury By Urinary Neutrophil Gelatinase Associated Lipocalin In Adult Critically Ill Patients.

BACKGROUND: Acute kidney injury (AKI) is a major cause of mortality and morbidity in the hospitalized patients. It is also a risk factor for chronic kidney disease and advance renal failure. Early diagnosis with new biomarkers for AKI can prevent and/or reverse the process before rise in serum creatinine and symptomatic renal failure. This study is aimed at the accuracy of Urine neutrophil gelatinase associated lipocalin (NGAL) for detection of AKI at an early stage. METHODS: It is a descriptive, cross sectional study conducted in the Medical Intensive Care Unit of Shifa International Hospital, Islamabad. Total 97 patients admitted in intensive care unit, age from 18-75 years, fulfilling the inclusion criteria were included by non-probability, consecutive sampling technique. Duration of study was six months, from 1st February 2014 till 31st July 2014. Urine samples of study population were tested for NGAL and simultaneously serum creatinine levels were checked, which were repeated at 48 hours for diagnosis of AKI. Patients with AKI and positive values of NGAL were considered true positive while patients without AKI and negative values of NGAL were considered true negative. Accuracy of NGAL was then calculated and effect modifiers like age and gender checked by chi square testing.. RESULTS: Mean age of the participants was 57.76 years with the range of 26-74 years. Out of the total population of 97 patients, 48.5% were males and remainder 51.5% were females. The study found that the accuracy of the urinary NGAL in diagnosis of AKI when compared with serum creatinine was 90.7%.. CONCLUSIONS: Urine NGAL is an accurate marker of AKI in critically ill patients. Therefore, it should be included in the diagnostic workup of AKI in early stages..

Association Between Delayed Graft Function (DGF) Biomarkers and Long-term Outcomes After Living Donor Kidney Transplantation.

BACKGROUND AND OBJECTIVES: The association between preoperative Urine Neutrophil Gelatinase-associated Lipocalin (uNGAL) and interleukin-18 (uIL-18) with poor 1-year allograft function has been shown in deceased-donor kidney transplant recipients previously, and also these markers could predict 3-month allograft function. However, it is unknown whether there is an association between these postoperative biomarkers with important recipient outcomes beyond this time in livedonor transplants. METHODS: NGAL and IL-18 four and 24 hours were measured in live-donor kidney transplant recipients after transplantation. The relationships between changes in these markers with clinical outcomes as well as kidney function were examined at 1 month and 2 years. Moreover, the association between delayed graft function with clinical outcome and Serum Creatinine (SrCr) was evaluated during this period. RESULTS: The Mean age for kidney recipients was 23.9 years. Significant interaction was observed between uNGAL 24 hr (pvalue=0.01) and uIL-18 four and 24 hr after transplantation (pvalue=0.04, 0.03; respectively) with patients' outcome after 1 month and changes in uNGAL with outcomes after 2 years (pvalue= 0.04). CONCLUSION: Changes in urine NGAL postoperative are associated with worst outcomes, 2 years after kidney transplantation, suggesting its potential role in identifying patients that are at high risk for diminished allograft function, outcome and survival.

The Effect of Furosemide on the Level of Neutrophil Gelatinase-associated Lipocalin in Critically Hospitalized Patients with Acute Kidney Injury.

BACKGROUND AND AIMS: Oliguric acute kidney injury (AKI), commonly attributed to a more severe degree of renal injury, is associated with poorer prognosis than nonoliguric form. The aim of this study was to determine the effect of furosemide therapy on kidney function and on the level of neutrophil gelatinase-associated lipocalin (NGAL) in critically hospitalized patients in the Intensive Care Unit (ICU). MATERIALS AND METHODS: In this randomized controlled trial, 106 ICU patients with AKI were assigned into furosemide and control groups. In furosemide group, 40-80 mg of intravenous furosemide was administrated, followed by 1-5 mg/h furosemide infusion. In control group, patients received standard treatment. Serum and urinary NGAL were measured on the 1st, 3rd, and 7th days of the study. RESULTS: The results of this study indicated that during the study, serum blood urea nitrogen levels of patients increased in both groups; this, however, was significant only in the control group (P = 0.009). Both plasma and urine NGAL decreased significantly (P < 0.05) in both groups. The findings of 28-day mortality follow-up revealed that 20% and 28% of patients died in the furosemide and the control groups, respectively. CONCLUSIONS: NGAL was not found to reflect any positive or negative effects of Furosemide in patients with AKI.

Medición del NGAL urinario en el donante para detectar función retardada del injerto renal en el receptor / NGAL as a marker to detect donor risk factors for delayed graft function

Resumen Introducciónen el trasplante renal de donante fallecido es importante tener marcadores tempranos que ayuden a predecir la funcionalidad adecuada del injerto renal. La medición de creatinina continóa siendo el marcador de elección para definir si los riñones de un posible donante son aptos para ser trasplantados. La lipocalina asociada a la gelatinasa del neutrófilo urinaria (NGALu) es un biomarcador que ha sido utilizado para el diagnóstico temprano de lesión renal aguda, pero su comportamiento es incierto en el donante fallecido. Este estudio tiene como objetivo determinar si los niveles de NGALu del donante pueden predecir la función retardada del injerto (FRI) en los receptores. Métodología: cohorte prospectiva en la que se evaluaron los niveles de NGALu del donante al momento de la extracción renal; se aplicó estadística descriptiva y pruebas no paramétricas. Se exploró el comportamiento de este biomarcador en el donante del injerto renal para determinar si es un factor predictivo de función retardada del injerto. Resultados: se evaluaron 27 donantes de criterios óptimos; el 74,1 % eran hombres, la edad tuvo una mediana de 27 años (rango: 18,8-43,3); la principal causa de muerte fue trauma encefalocraneano, seguido por el accidente cerebrovascular. La creatinina tuvo una mediana de 0,8 mg/dl y los valores de NGALu tuvieron una mediana de 11,1ng/ml (4,2-33,6). En total se realizaron 46 trasplantes, de los cuales el 15,2 % presentaron función retardada del injerto y dos pacientes necesitaron terapia de reemplazo renal en la primera semana luego del trasplante. Los valores de NGALu agrupados de acuerdo a presencia o no de función retardada del injerto fueron de 11,1 ng/ml (3-17,3) en los pacientes sin función retardada del injerto y 11,2 ng/ml en los pacientes con dicha función (7,7-39,4) (p=0,40). En el análisis multivariado no se encontró ningón factor asociado al desarrollo de función retardada del injerto. Conclusión: en este estudio la medición de uNGAL en donantes fallecidos de criterios óptimos no predijo función retardada del injerto.

Abstract Introduction: For deceased donor renal transplantation, it is important to have early markers that can predict the functional outcome of the transplant. Currently, creatinine is the marker of choice for determining whether a potential donor's kidneys are suitable for transplantation. Urine neutrophil gelatinase-associated lipocalin (uNGAL) is a biomarker that has been utilized to diagnose early-stage acute kidney injury, but its behavior in deceased donors is uncertain. The objective of this study was to determine whether donor uNGAL levels can predict delayed graft function in recipients. Methodology: A prospective cohort utilizing descriptive statistics and non-parametric median tests was carried out to evaluate donor uNGAL levels at the time of kidney removal. The behavior of this biomarker was analyzed in kidney transplant donors to evaluate its use as a predictive factor for DGF. Results: A total of 27 standard criteria transplants were evaluated, including 7 (25.9%) women and 20 (74.1%) men with a median age of 27 years (18.75-43.25). The principal cause of death was traumatic head injury, followed by stroke. The median creatinine level was 0.8 mg/dl (0.57-1), and the median uNGAL level was 11.1 ng/ml (4.2-33.6). In total, 46 transplants were performed, of which 15.22% (7 patients) presented with delayed graft function and 2 patients needed renal replacement therapy within the first week after transplantation. The patients were grouped according to the presence of DGF, with median uNGAL values of 11.1 ng/ml (3-17.3) in patients without DGF and median values of 11.2 ng/ml (7.7-39.4) (p=0.4) in those with delayed graft function. No factors were found to be associated with the development of delayed graft function in the multivariate analysis. Discussion: in this study, uNGAL measurements in deceased standard criteria donors did not predict delayed graft function.

Clinical utility of urine neutrophil gelatinase-associated lipocalin measured at admission to predict outcomes in heterogeneous population of critically ill patients.

Urine neutrophil gelatinase-associated lipocalin (uNGAL) is a reliable early biomarker of acute kidney injury (AKI) in a homogeneous patient population. However, its utility in a heterogeneous population of critically ill, in whom the time of onset of renal insult is often unclear, is not clearly established. We evaluated the ability of a single measurement of uNGAL in a heterogeneous adult population, on admission to intensive care unit (ICU), to predict the occurrence of AKI and hospital mortality. One hundred and two consecutive adult patients had uNGAL measured within 8 h of admission to ICU. The demographic and laboratory data were collected at admission. The diagnosis of AKI was based on AKI Network (AKIN) criteria. The primary outcome was the development of AKI, and the secondary outcome was hospital mortality. The mean age was 54 ± 16.4 years and 65% were males. Urine NGAL (ng/ml) was 69 ± 42 in patients with AKI (n = 42) and 30.4 ± 41.7 in those without AKI (P < 0.001). The area under the receiver operating characteristic (ROC) curve for prediction of AKI was 0.79 and for serum creatinine (SCr) was 0.88. The sensitivity and specificity for a cut-off value of uNGAL of 75 ng/ml to predict AKI were 0.5 and 0.85 respectively. uNGAL > 75 ng/ml was a strong (odd ratio = 5.17, 95% confidence interval: 1.39-19.3) and independent predictor of hospital mortality. A single measurement of uNGAL at admission to ICU exhibited good predictive ability for AKI though the sensitivity was low. The predictive ability of uNGAL was inferior to simultaneously measured SCr at admission, hence limited its clinical utility to predict AKI. However, admission uNGAL was a strong, independent predictor of hospital mortality.

High serum and urine neutrophil gelatinase-associated lipocalin levels are independent predictors of renal progression in patients with immunoglobulin A nephropathy.

BACKGROUND/AIMS: Tubulointerstitial injury plays an important role in the progression of immunoglobulin A nephropathy (IgAN), and neutrophil gelatinase-associated lipocalin (NGAL) is among the most sensitive tubular biomarkers. We investigated whether serum or urine NGAL predicts prognosis in patients with IgAN. METHODS: The present study enrolled patients with biopsy-proven IgAN from January 2005 to December 2010, whose serum and urine samples at the time of kidney biopsy were preserved by freezing. We retrospectively reviewed patient clinical data and followed patients until October 2012. Serum and urine NGAL levels were measured using an enzyme-linked immunosorbent assay kit. Renal progression was defined as an estimated glomerular filtration rate decline by > 50% or progression to end-stage renal disease. RESULTS: There were 121 patients enrolled in this study. During the median follow-up period of 41.49 months, renal progression was found in nine patients (7.4%). Serum or urine NGAL alone could not predict renal progression; however, when serum and urine NGAL levels were combined, belonging to the high NGAL group independently predicted renal progression (hazard ratio [HR], 5.56; 95% confidence interval [CI], 1.42 to 21.73; p = 0.014), along with tubular damage graded according to the Oxford classification as T2 (HR, 8.79; 95% CI, 2.01 to 38.51; p = 0.004). In addition, a Kaplan-Meier curve of renal survival showed significantly higher renal progression in patients in the high NGAL group (log rank, p = 0.004). CONCLUSIONS: In patients with IgAN, high serum and urine NGAL levels at the time of kidney biopsy predict renal progression.

A double-blind, randomized, controlled trial on N-acetylcysteine for the prevention of acute kidney injury in patients undergoing allogeneic hematopoietic stem cell transplantation.

Acute kidney injury (AKI) is one of the complications of hematopoietic stem cell transplantation and is associated with increased mortality. N-acetylcysteine (NAC) is a thiol compound with antioxidant and vasodilatory properties that has been investigated for the prevention of AKI in several clinical settings. In the present study, we evaluated the effects of intravenous NAC on the prevention of AKI in allogeneic hematopoietic stem cell transplantation patients. A double-blind randomized placebo-controlled trial was conducted, and 80 patients were recruited to receive 100 mg/kg/day NAC or placebo as intermittent intravenous infusion from day -6 to day +15. AKI was determined on the basis of the Risk-Injury-Failure-Loss-End-stage renal disease and AKI Network criteria as the primary outcome. We assessed urine neutrophil gelatinase-associated lipocalin (uNGAL) on days -6, -3, +3, +9 and +15 as the secondary outcome. Moreover, transplant-related outcomes and NAC adverse reactions were evaluated during the study period. Statistical analysis was performed using appropriate parametric and non-parametric methods including Kaplan-Meier for AKI and generalized estimating equation for uNGAL. At the end of the trial, data from 72 patients were analysed (NAC: 33 patients and placebo: 39 patients). Participants of each group were not different considering baseline characteristics. AKI was observed in 18% of NAC recipients and 15% of placebo group patients, and the occurrence pattern was not significantly different (p = 0.73). Moreover, no significant difference was observed between groups for uNGAL measures (p = 0.10). Transplant-related outcomes were similar for both groups, and all patients had successful engraftment. Three patients did not tolerate NAC because of abdominal pain, shortness of breath and rash with pruritus and were dropped from the intervention group before transplantation. However, the frequency of adverse reactions was not significantly different between groups. In conclusion, our findings could not show any clinical benefits from high-dose NAC particularly for AKI prevention in allogeneic hematopoietic stem cell transplantation patients.

High serum and urine neutrophil gelatinaseassociated lipocalin levels are independent predictors of renal progression in patients with immunoglobulin A nephropathy

BACKGROUND/AIMS: Tubulointerstitial injury plays an important role in the progression of immunoglobulin A nephropathy (IgAN), and neutrophil gelatinase-associated lipocalin (NGAL) is among the most sensitive tubular biomarkers. We investigated whether serum or urine NGAL predicts prognosis in patients with IgAN. METHODS: The present study enrolled patients with biopsy-proven IgAN from January 2005 to December 2010, whose serum and urine samples at the time of kidney biopsy were preserved by freezing. We retrospectively reviewed patient clinical data and followed patients until October 2012. Serum and urine NGAL levels were measured using an enzyme-linked immunosorbent assay kit. Renal progression was defined as an estimated glomerular filtration rate decline by > 50% or progression to end-stage renal disease. RESULTS: There were 121 patients enrolled in this study. During the median follow-up period of 41.49 months, renal progression was found in nine patients (7.4%). Serum or urine NGAL alone could not predict renal progression; however, when serum and urine NGAL levels were combined, belonging to the high NGAL group independently predicted renal progression (hazard ratio [HR], 5.56; 95% confidence interval [CI], 1.42 to 21.73; p = 0.014), along with tubular damage graded according to the Oxford classification as T2 (HR, 8.79; 95% CI, 2.01 to 38.51; p = 0.004). In addition, a Kaplan-Meier curve of renal survival showed significantly higher renal progression in patients in the high NGAL group (log rank, p = 0.004). CONCLUSIONS: In patients with IgAN, high serum and urine NGAL levels at the time of kidney biopsy predict renal progression.

The role of urinary neutrophil gelatinase-associated lipocalin in lupus nephritis.

BACKGROUND: Urine neutrophil gelatinase-associated lipocalin (uNGAL) has been proposed as a potential biomarker for lupus nephritis (LN) activity. We determined the association between uNGAL with LN activity in systemic lupus erythematosus (SLE) patients compared to the current standard markers of SLE. METHODS: A total of 100 SLE patients with biopsy-proven LN were recruited-47 with active and 53 inactive LN. uNGAL levels were measured. Renal function test, urinary parameters, lupus serology and calculated renal SLE Disease Activity Index-2K (renal SLEDAI-2K) were analyzed to determine their associations with uNGAL. RESULTS: Normalized uNGAL levels (ng/mg creatinine) were significantly higher in patients with active LN compared to those with inactive disease (p=0.01). uNGAL and renal SLEDAI-2K were associated (r=0.32, p=0.001). Multiple logistic regression showed that only serum creatinine and renal SLEDAI-2K were independent predictors of uNGAL levels (p=0.03 and 0.02 respectively). Analysis of the receiver operating characteristic (ROC) curve showed that uNGAL was a potential biomarker for LN. CONCLUSIONS: uNGAL was increased in active LN especially in LN flares. Serial measurements of uNGAL levels may be of value in monitoring response of LN to treatment and for predicting LN flares.

Changes of urine neutrophil gelatinase associated lipocalin in patients with diabetic nephropathy and the related clinical significance / 第二军医大学学报

Objective To investigate the changes of urine neutrophil gelatinase associated lipocalin (uNGAL) in patients with diabetic nephropathy (DN) and the related clinical significance. Methods Eighty-seven T2DM patients were divided into high albuminuria group (including both miroalbuminuria \[MA\] and clinical nephropathy \[CN\] patients, uAlb/uCr≥30 mg/mmol) and normal albuminuria (NA) group (uAlb/uCr<30 mg/mmol) according to the ratio of urinary albumin to urinary creatinine abundance. Forty normal subjects were recruited as control.The uNGAL level was measured by ELISA; plasma glucose, blood lipids(TC, TG, HDL-C, and LDL-C) abundance were also analyzed. Results The high albuminuria group had the highest uNGAL level, followed by normal albuminuria group and control group, and the former two groups had significantly higher uNGAL levels than the control group (P<0.01). Logistic regression analysis showed that uAlb/uCr, uNGAL, FBG and TG levels were positively correlated with the progress of DN (ruAlb/uCr= 0.16, ruNGAL=0.18, rFBG=0.41, and rTG=0.72, P<0.05); HDL-C was negatively correlated with the progress of DN (rHDL-C=-2.19, P<0. 01). Conclusionu NGAL level is significantly increased in DN patients and correlated with the degree of kidney damage. uNGAL may serve as an indicator for early diagnosis of DN. The elevated plasma glucose and blood lipids can accelerate the progress of DN.