Abstract: Objective To explore the value of combined detection of urinary kidney injury molecule-1, interlukin-18 (IL-18) and serum cystatin C in the early diagnosis of acute kidney injury in children with primary nephrotic syndrome. Methods We enrolled 153 children with primary nephrotic syndrome and detected urinary kidney injury molecule-1, IL-18 and serum cystatin C. We compared the levels of these indicators in children with different degree of renal injury, and analyzed the diagnostic value of combined detection. Results The levels of urine kidney injury molecule-1, IL-18 and serum cystatin C in the acute kidney injury group (49/157, 32.03%) were higher than those without acute kidney injury (108/157, 67.97%) (P<0.05). The levels of urinary renal injury molecule-1, IL-18 and serum cystatin C in children with different acute kidney injury severity levels showed statistically differences (P<0.05). ROC analysis results showed that the diagnostic cut-off values of urinary kidney injury molecule-1, IL-18, and serum cystatin C in children with primary nephrotic syndrome with acute kidney injury were 3.87 μg/mL, 271.04 pg/mL and 1.23 mg/L respectively, and the AUC of combined diagnosis was 0.884, which diagnostic efficiency was higher than that of single examination (P<0.05). Conclusions Urinary kidney injury molecules-1, IL-18 and serum cystatin C can be used as diagnostic indicators for acute kidney injury in children with primary nephrotic syndrome, and combined detection can improve the diagnostic efficiency.

Key words: Urinary kidney injury molecule-1, Interlukin-18 (IL-18), Serum cystatin C, Primary nephrotic syndrome, Acute kidney injury, Early diagnosis