The standard metrics used to monitor the progression of acute kidney injury (AKI) include markers such as serum creatinine, blood urea nitrogen, and estimated glomerular filtration rate (eGFR). Moreover, neutrophil gelatinase-associated lipocalin (NGAL) expression has been reported to modulate oxidative stress.

We aimed to evaluate the usefulness of serum NGAL levels for monitoring renal function after radical nephrectomy (RN). We prospectively collected data from 30 patients who underwent RN. We analyzed serum NGAL and creatinine at 6 time points: preoperative day 1, right after surgery, 6 hours after surgery, postoperative day (POD) 1, POD 3, and POD 5. We compared these measurements according to the eGFR values (classified as chronic kidney disease stage III; CKD III or not) using data obtained 3 months after surgery.

The mean age was 65.5 years (range, 45–77 years), and the male-to-female ratio was 2:1. At the last follow-up examination, there were 12 patients (40%) with CKD III. Using receiver operating characteristic analysis, we found that serum creatinine on POD 5 (area under the curve [AUC], 0.887; P = 0.000) and NGAL at 6 hours after LRN (AUC, 0.743, P = 0.026) were significant predictors of CKD III. The development of CKD III after LRN was associated with the serum creatinine level on POD 5 and the NGAL at 6 hours after surgery.

Compared to serum creatinine, serum NGAL enabled earlier prediction of postoperative CKD III. Therefore, serum NGAL measured 6 hours after surgery could be a useful marker for managing patients after RN.

The neutrophil gelatinase-associated lipocalin (NGAL) level following non cardiac surgery is useful for predicting acute kidney damage. However, there is insufficient conclusive evidence as to whether NGAL can be used to predict subclinical AKI following non-cardiac surgery.

We measured serum NGAL and creatinine levels in 41 patients following non-cardiac surgery, and the increase of these variables was used to predict acute decreases in kidney function.

The study included a total of 41 patients. The mean age was 64.65 ± 17.09 years. The serum creatinine concentration was increased 12 hours after surgery. The mean SD serum NGAL decreased after 4hours after surgery and continued to decrease after 12 hours after surgery. The incidence of subclinical AKI determined by the 4 hour serum NGAL level was 10(24.4%), and the incidence of serum creatinine elevation was 0(0.0%). The incidence of subclinical AKI determined by the 12 hour serum NGAL level was 4(9.8%), and the incidence of subclinical AKI determined by serum creatinine was 4(9.8%). The elevation of NGAL was more rapid than the serum creatinine 4 hours after surgery

We verified the usefulness of the serum NGAL level as a predictive factor for subclinical AKI after non-cardiac surgery.