Development of a Novel Clinical and Radiologic Risk Score to Predict Septic Complications After Urinary Decompression...

Well-defined clinical predictors of sepsis after upper tract drainage for obstructive uropathy are lacking. The study aim is to develop a data-driven score to predict risk of sepsis after decompression of the upper urinary tract. Complete clinical and radiologic data from 271 patients entering the emergency department for obstructive uropathy and submitted to stent/nephrostomy tube decompression were evaluated. The Charlson Comorbidity Index (CCI) was used to score comorbidities. The definition of sepsis was an increase in ≥2 Sequential Organ Failure Assessment points (or a postoperative persistently elevated score +1 additional increase) and documented blood or urine cultures. Descriptive statistics and stepwise multivariable logistic regression modeling with receiver operating characteristic analysis were performed to obtain a composite risk score to predict the risk of sepsis after surgery. This study was approved by our local Ethics Commitee (Prot. 25508). Fifty-five (20.3%) patients developed sepsis. At multivariable analysis, CCI ≥2 (odds ratio [OR] 3.10; 95% confidence interval [CI] 1.36-7.04), maximum body temperature ≥38°C (OR 4.35; 95% CI 1.89-9.44), grade III-IV hydronephrosis (OR 2.37; 95% CI 1.10-4.98), HU of the dilated collecting system ≥7.0 (OR 4.47; 95% CI 2.03-9.81), white blood cells ≥15 × 10³/mmc (OR 2.77; 95% CI 1.24-6.19), and C-reactive protein ≥10 (OR 3.27; 95% CI 1.41-7.56) were independently associated with sepsis. The positive predictive value of a true sepsis increased incrementally as a function of number of positive variables, ranging from 1.6% to 100.0% among patients with 1 and 6 positive variables, respectively. Our risk score identifies accurately patients with an increased risk of sepsis after urinary decompression for obstructive uropathy, hence improving clinical management.