IS IT POSSIBLE TO PREDICT THE RISK OF INFECTIOUS COMPLICATIONS FROM THE CONSULTATION WHEN PROPOSING A PERCUTANEOUS NEPHROLITHOTOMY?

INTRODUCTION AND OBJECTIVE: Infectious complications (IC) after percutaneous nephrolithotomy (PNL) are serious complications that can put patients' lives at risk. Our objective was to analyze the predictors of IC before making a PNL. METHODS: A prospective study was designed, from January 2013 to June 2018, which included 386 patients undergone a PNL for lithiasic reasons. We defined postoperative IC as a SIRS or sepsis (classic criteria). The analyzed variables were: age, sex, diabetes mellitus, body mass index (BMI), lithiasis side, size, Hounsfield Units (HU), preoperative culture, surgical time and sheath´s caliber. A bivariate analysis (Chi2 and t-Student) and a multivariate analysis (binary logistic regression) were performed. RESULTS: Out of 386 PNL 189 procedures were performed in men (49%) and 197 in women (51%), with a mean age of 52.75 years (± 14.74) and an average BMI of 27.29 (± 6.09). Only 15% of the patients were diabetic, of which 4.5% were insulin dependent. 206 procedures were performed in the right kidney (53.37%), 177 on the left side (45.85%), 2 bilateral (0,52%) and 1 in a transplanted kidney (0,26%). The greater diameter average of the lithiasis was 25.88 mm (± 14.05) with an average of 1000.8 UH (± 322.54). We used a 30 Fr sheath in 265 procedures (68.7%). The mean surgical time was 118.23 minutes (± 41.66). The preoperative culture was available in 346 procedures (89.6%), with a positive result in 124 cases (35.84%) IC were produced in 57 patients (14.77%); 28 patients (49.1%) developed SIRS and 29 sepsis (50.9%). IC were more frequent in women; 44 of 197 (22.3%) with p <0.001. IC are more frequent in stones with a diameter greater than 30 mm (IC95% 26.65-35.33) and in synchronous procedures (p 0.049). From the 57 IC-patients, 34 patients presented a previous positive urine culture (59.7%), 18 negative (31.6%) and 5 contaminated (8.7%) (p <0.001). In the binary logistic regression, we obtained as preoperative predictors factors: female gender OR 3.4 (95% CI 1.6-7.3), insulin-dependent diabetes OR 1.5 (95% CI 0.28-8), non-insulin-dependent diabetes OR 1.6 (95% CI 0.4-3.33), lithiasic size OR 1.02 (95% CI 1-1.04) and positive preoperative urine culture OR 4 (95% CI 2.17-7.33) with p <0.001. CONCLUSIONS: Diabetic women with large lithiasic size and positive preoperative culture have a higher risk of IC, that we should consider prior to surgery. In this group of patients, our advice is to keep a close monitoring in the early postoperative period. Moreover, we do not recommend performing bilateral procedures in a synchronized way. Source of Funding: NO