Predictive value of serum neutrophil gelatinase-associated lipocalin and cystatin C as markers for contrast nephropathy in patients undergoing coronary angiography

ABSTRACT

Contrast induced-nephropathy is a more frequent and potentially serious complication after coronary angiography. Very few biomarkers exist for monitoring contrast induced-nephropathy. Recently, serum neutrophil gelatinase-associated lipocalin [NGAL] represents a novel biomarker for early identification of acute kidney injury. The present work aimed to test the hypothesis that NGAL could represent an early biomarker for kidney injury and to assess the relation ship between NGAL and serum creatinine and cystatin C, in patients with normal serum creatinine undergoing percutaneous coronary angiography. The study was performed on thirty non-diabetic patients with normal serum creatinine, undergoing coronary angiography due to corollary artery disease. All patients were mateched for age and body mass index. following full clinical examination, fasting blood sample were withdrawn for estimation of blood glucose. glycosylated hemoglobin, lipid profile. creatinine as well as NGAL and cystatin C before coronary angiography. Another blood samples were taken 4 and 24 hours after coronary angiography for all patients for evaluation of serum creatinine, NUGL and cystatin C. There was a significant increase in serum NGAL level 4 hours and 24 hours after coronary interventions when compared to the baseline value before coronary- angiography Before coronary angiography, serum NGAL was positively correlated with serum creatinine, and cystatin C. in multiple regression analysis, serum creatinine was the only predictor of serum NGAL. Serum NGAL, 4 hour after coronary angiography, correlated with serum ereatinine only in simple and multiple regression analysis. On the other hand, serum cystatin C level increased significantly only 24 hour after coronary angiography compared to the baseline value before coronary angiography. In a simple regression analysis serum cystain C correlated positively to systolic and diastolic blood pressure, Serum creatinine and serum NGAL, before Coronary angiography. In multiple regression analysis, serum creatinine and systolic blood pressure were the predictors of serum cystatin C. Serum NGAL and cystatin C could be valuable in the detection of acute renal impairment after coronary angiography. However current diagnostic methods such as. Serum creatinine or cystatin C measurements only respond after renal function has deteriorated. Therefore, the presence of new early markers for renal injury such as NGAL, can initiate proper management of acute renal failure within hours rather than days of the insult