[Acute kidney injury after laparoscopic radical nephrectomy: role of the renin-angiotensin system and the predictive value of its activation status].

Objective: To investigate the role of the renin-angiotensin system (RAS) in the pathogenesis of acute kidney injury (AKI) after laparoscopic radical nephrectomy (LRN) and the predictive value of RAS activation status for AKI.

Methods: Eighty-two patients undergoing LRN at the Third Medical Center of General Hospital of PLA from December, 2023 to March, 2024 were enrolled, including 57 with postoperative AKI and 25 without AKI according to KDIGO criteria. Blood and urine samples were collected from the patients before and at 24 h after the operation for analyzing the correlation of urinary aldosterone, plasma ACE2, Ang1-7, Nrf-2, and IL-10 levels with postoperative AKI. Univariate and multivariate logistic regression analyses and ROC curve were employed to identify the risk factors for postoperative AKI and their predictive value for AKI.

Results: Compared with those without postoperative AKI, the patients with AKI had significantly higher postoperative urinary aldosterone levels and lower plasma ACE 2, Ang 1-7, Nrf-2, and IL-10 levels (P < 0.05). Postoperative urinary aldosterone level was positively correlated with AKI and negatively with estimated glomerular filtration rate (eGFR) (P < 0.05); plasma levels of ACE 2, Nrf-2, and IL-10 were all negatively correlated with AKI and positively with eGFR. Urinary aldosterone was a risk factor and plasma ACE 2, Ang 1-7, Nrf-2 and IL-10 were protective factors for AKI, and among them urinary aldosterone was an independent risk factor (AUC=0.651) and plasma Nrf-2 was an independent protective factor (AUC=0.679). The unconventional RAS pathway indices had an AUC of 0.758, and aldosterone combined with the unconventional pathway indices had an AUC of 0.788 for predicting postoperative AKI.

Conclusion: Activation of the conventional RAS pathway and suppression of the unconventional pathway contribute to AKI following LRA possibly by affecting eGFR. Aldosterone combined with the unconventional pathway indicators can predict the occurrence of AKI after LRN.