A nomogram based on preoperative CT secondary signs and clinical factors to predict post-PCNL fever in patients with Escherichia coli infection.

To assess secondary signs on preoperative CT as predictive factors for fever after percutaneous nephrolithotomy (PCNL) in patients with Escherichia coli infection, and to develop a prediction model using clinical and radiological signs. We conducted a retrospective review of 171 patients with E. coli infection who underwent PCNL. Univariable and multivariable analyses were conducted to verify the predictive value of secondary signs on preoperative CT and other clinical variables for post-PCNL fever (> 38℃). In addition, a nomogram was created for clinical application. Thirty-three patients (19.3%) developed fever after PCNL. Multivariate analysis revealed that CT value (Hounsfield unit - HU) of hydronephrosis (OR 1.171, P < 0.001), perinephric fat stranding (OR 3.347, P = 0.015), Neutrophil-lymphocyte ratio (NLR) (OR 1.311, P = 0.003) and multiple calculi (OR 3.299, P = 0.030) were independent predictors of post-PCNL fever in patients with E. coli infection. The above independent predictors were used as variables to construct the nomogram. The nomogram model was internally validated and the area under the curve of this model was 0.830. Secondary signs including CT value of hydronephrosis and perinephric fat stranding on preoperative CT, NLR, and multiple calculi are independent predictive factors for post-PCNL fever in patients with E. coli infection. The nomogram might be beneficial for urologists to calculate quickly the probability of postoperative fever in these patients.