The evaluation of acute kidney injury due to ischemia by urinary neutrophil gelatinase-induced lipocalin (uNGAL) measurement in patients who underwent partial nephrectomy

Purpose To investigate the role of urinary neutrophil gelatinase-induced lipocalin (uNGAL) measurement in the early diagnosis of acute kidney injury that may occur after intraoperative ischemia in patients undergoing partial nephrectomy (PN). Methods This prospective study included 86 patients who underwent open laparoscopic or robotic partial nephrectomy between May 2017 and May 2019. During the surgery, whether the patients had ischemia or not, type of vascular clamping and the ischemia time were noted. The definition of acute kidney injury (AKI) was classified according to Acute Kidney Injury Network (AKIN) criteria. Urine samples were collected preoperatively and 3 h after renal pedicle clamp removal and uNGAL was measured. Results AKI was recorded in 34 (39.5%) of 86 patients after PN. Of the 34 patients, 26 (76.4%) had level 1 and 8 (23.6%) had level 2 AKI. uNGAL levels increased significantly as an early reflection of AKI in patients who underwent intraoperative total or renal artery clamping (p = 0.024). There was no significant postoperative increase in uNGAL in the non-ischemic group (p = 0.163). uNGAL expression was detected well before serum creatinine increase. Patients with AKI after PN had higher uNGAL expression (p = 0.008) However, there was no correlation between the level of AKI and uNGAL expression (r = 0.201,p = 0.066). Conclusion Ischemic acute kidney injury after nephron-sparing surgery can be detected early by uNGAL measurement. In future studies comparing outcomes of different surgical techniques on renal functions after PN, uNGAL levels may be used.

Automated summary

Urinary neutrophil gelatinase-induced lipocalin (uNGAL) measurement plays an important role in the early diagnosis of ischemic acute kidney injury after partial nephrectomy. In patients with intraoperative ischemia, uNGAL levels significantly increased, serving as an early indicator of acute kidney injury. Additionally, the expression of uNGAL was detected before a rise in serum creatinine levels.