Predictive Value of Combined Serum Nuclear Factor Erythroid 2-Related Factor 2 and Prognostic Nutritional Index for Sepsis after Percutaneous Nephrolithotomy

<b><i>Objective:</i></b> This prospective observational study aimed to explore the predictive value of serum nuclear factor erythroid 2-related factor 2 (Nrf2) levels and its combination with the prognostic nutritional index (PNI) for postoperative sepsis in patients undergoing percutaneous nephrolithotomy (PCNL) for renal stones. <b><i>Methods:</i></b> This prospective observational study included 112 patients with renal stones who underwent PCNL surgery in our hospital from January 2023 to December 2023. The diagnosis of sepsis was based on the third international consensus definitions for sepsis and septic shock (Sepsis-3). Clinical data on all patients were collected, and the PNI index was calculated. The serum levels of Nrf2, interleukin-6 (IL-6), interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and C-reactive protein (CRP) in all patients were measured using enzyme-linked immunosorbent assay. Data analysis was performed using Statistical Package for the Social Sciences (SPSS) 25.0 statistical software. <b><i>Results:</i></b> Compared with the nonsepsis patients, the sepsis patients had a higher proportion of positive preoperative urine cultures, longer activated partial thromboplastin time, and lower PNI scores. At 6, 12, and 24 hours after surgery, the sepsis patients had significantly lower serum Nrf2 levels and higher levels of IL-6, IL-1β, TNF-α, and CRP. Pearson's analysis showed a negative correlation between serum Nrf2 levels and IL-6 and CRP levels. The combination of PNI and serum Nrf2 levels at 24 hours after surgery had a higher predictive level, with an Area Under the Curve (AUC) of 0.844, a sensitivity of 75.3%, and a specificity of 77.8%. Finally, logistic regression analysis showed that decreased serum Nrf2 level at 24 hours after surgery was a risk factor for postoperative sepsis in renal stone patients. <b><i>Conclusion:</i></b> In conclusion, our study results indicate significantly lower serum Nrf2 levels in postoperative sepsis patients undergoing PCNL. Serum Nrf2 levels in combination with PNI can be used to predict the occurrence of postoperative sepsis in renal stone patients undergoing PCNL.