Comparison of serum creatinine and spot urine interleukin-18 levels following radiocontrast administration

Radiocontrast administration is an important cause of acute renal failure. In this study, compared the plasma creatinine levels with spot urine IL-18 levels following radiocontrast administration. Twenty patients (11 males, 9 females) underwent radiocontrast diagnostic and therapeutic-enhanced examinations. The RIN Mehran risk score was low (≤5). The radiocontrast agents used were 623 mg/mL Iopromid (1.5 mL/kg), and 100 mL of 650 mg/mL meglumine diatrizoate as three-way oral and rectal contrast material for abdominal computed tomography (CT) scans. Serum blood urea nitrogen, creatinine, Na, K, Cl, Ca, P, creatinine clearance, and spot urine IL-18 levels were analyzed before and repeated at 24, 48, and 72 h after radiocontrast administration. Six and 24-h urinary IL-18 levels were measured with a human IL-18 ELISA kit following radiocontrast administration. An increase in plasma creatinine 24 and 48 h following radiocontrast administration was observed compared with precontrast values, but it was not statistically significant (P=0.052 and P=0.285, respectively). A statistically significant increase in IL-18 levels was observed at 6 and 24 h, compared with precontrast values (P=0.048 and P=0.028, respectively). A tendency for postcontrast 24-h urinary IL-18 levels to increase was observed compared with 6 h, but the increase was not statistically significant (P=0.808). Our results show that plasma creatinine starts to increase at 24(th) hour; however, spot urine IL-18 levels go up at 6(th) hour following radiocontrast administration implying urine IL-18 to be an earlier parameter for kidney injury.