Ureteral Stent Colonization and Urinary Tract Infection in Children Undergoing Minimally Invasive Pyeloplasty.

INTRODUCTION: Minimally invasive pyeloplasty (MIP), namely, laparoscopic and robot-assisted interventions, has gained popularity in recent years. Double-J ureteral stents are frequently inserted during surgery. Foreign bodies in the urinary tract are considered as risk factor for developing urinary tract infection (UTI). This study aimed to specify the bacteria cultured from urine and stents responsible for UTI in children with indwelling ureteral stents undergoing MIP. PATIENTS AND METHODS: We retrospectively reviewed medical records of 30 children (22 boys and 8 girls) who had undergone MIP between 2014 and 2017. Median age at surgery was 2.7 years (interquartile range [IQR]: 0.5-7.9). Urine cultures were obtained before surgery, before stent removal, 1 month after stent removal, and if UTI was suspected. Stents were removed 4 to 8 weeks after surgery and cultured. Patients' demographics, types of stents, and surgical details were recorded. RESULTS: Median stent indwelling time was 5.09 weeks (IQR: 4-6). Postoperative febrile UTI developed in 4/30 (13%) patients. Afebrile UTI occurred in another 4/30 (13%) patients. Stent cultures were positive in 19/30 (63%) patients. Stent and urinary cultures were identical in only one patient. Three of four patients with preoperative asymptomatic bacteriuria developed postoperative UTI. There was no association between UTI, gender, stent diameter, and duration of indwelling catheter. CONCLUSION: After MIP, febrile UTI and afebrile UTI occurred in about one quarter of patients. Pathogens isolated postsurgically from urinary cultures were unrelated to those colonizing the stents. Therefore, routine stent culturing is of low clinical significance. Moreover, small-caliber stents and longer indwelling periods were not risk factors for UTI. Optimizing antibiotic treatment for children with preoperative UTI may potentially prevent morbidity after surgery.

Multidetector Computed Tomographic Urography (MDCTU): Its Practical Role in Diagnosis of Upper Tract Urothelial Cancer in Patients 50 years and Older with Different Types of Hematuria.

MDCTU is a preferred method for the investigation of malignant lesions in the upper urinary tract. However, to decrease unnecessary radiation exposure the indications for the exam in different groups of patients should be assessed. In this study, we evaluated the role of MDCTU in patients older than 50 years who presented with different types of hematuria. In a retrospective manner, we assessed the radiologic reports of 173 patients ≥50 years who underwent MDCTU as a part of the evaluation for hematuria. To estimate the accuracy of MDCTU in the detection of upper urinary tract urothelial carcinoma (UUTUC) we compared MDCTU findings with the results of ureteroscopy. We also evaluated which factors can predict ureteroscopic confirmation of MDCTU-based diagnosis. In this list we also included diabetes mellitus and anticoagulant medications. As a result, 140 (103 males and 37 females) patients met the inclusion criteria. Mean patients' age was 69.7±16.98. Smokers and passive smokers comprised 38.6% and 26.4% of our patients, while 37.8% of our patients suffered from DM and 45% took anticoagulant medications. MDCTU suspected urothelial carcinoma in 17% (n=24) of our patients: UUTUC in eight and bladder urothelial carcinoma (BUC) in 16patients. Ureteroscopy had diagnosed UUTUC (with/without concurrent urothelial carcinoma of the bladder) in 9 patients: 6 with suspicious lesions in MDCTU and 3 additional patients with CIS/small low grade TCC. MDCTU had a sensitivity of 66.7%, specificity - 98.5%, positive predictive value - 75% and negative predictive value - 97.7%. The logistic regression model revealed five strong predictors for UUTUC: positive/atypical cytology, recurrent hematuria, MDCTU signs, age and Warfarin treatment. Finally a source of hematuria was diagnosed in 57% of patients, while MDCTU individual accuracy reached 42%. We found that MDCTU can effectively identify patients in whom further endoscopy is unnecessary. Otherwise, elder patients with positive/atypical cytology and recurrent microscopic hematuria, who have MDCTU signs and take Warfarin, should undergo endoscopic evaluation.