Risk factors for recurrent febrile urinary tract infection in patients with duplex collecting system

Abstract Purpose Our goal was to establish the risk factors for recurrent febrile urinary tract infection (F-UTI) in children with duplex collecting system (DCS). Methods Patients seen for DCS from 2010 to 2020 were retrospectively followed. Those with using continuous low dose antibiotic prophylaxis (CAP) and incompletely duplicated systems were removed from the study. The primary endpoint of this study was recurrent F-UTI. We conducted univariate analysis of 5 risk factors, namely, gender, affected side (unilateral vs bilateral), hydronephrosis grade of the affected renal unit, ureteral dilatation (UD) grade, type of anatomy. Results We analyzed medical reports of 305 patients, of which 74.8% were female. Among the 305 patients, F-UTI developed in in81/119 (68.1%) patients with ureterocele, in 7/9 (77.8%) patients with VUR, in27/36 (75%) patients with both ureterocele and VUR, in8/12 (66.7%) patients with ectopic and VUR, and in 49/105 (46.7%) patients with ectopic. Univariate analysis found discernible difference in type of DCS, ureteral dilatation and grade of hydronephrosis between recurrent F-UTI and non F-UTI patients. Moreover, Cox proportional regression analysis revealed that type of DCS, grade of hydronephrosis were stand-alone risk factors for recurrent F-UTI. Conclusion High hydronephrosis grade and the presence of ureterocele, VUR were stand-alone risk factors for recurrent F-UTI in children with DCS.