38 Abstract. – OBJECTIVE: Postoperative urine retention (POUR) is a well-known complication after total joint arthroplasty (TJA). POUR is most commonly managed with an indwelling catheter. However, indwelling catheters have been asso- ciated with a substantial risk of urinary tract in- fection (UTI). The purpose of this study was to (1) evaluate the incidence of UTI and POUR in patient with indwelling urinary catheter after TJA, (2) identify the microorganisms responsi- ble for catheter colonization, and (3) assess pre- operative risk factors (gender, body mass index, hypertension, diabetes mellitus, smoking) asso- ciated with catheter colonization. PATIENTS AND METHODS: Patients undergo- ing primary TJA with no preoperative bacteriuria were enrolled. Prior to the draping of the surgical site, each patient received an indwelling catheter that was inserted under sterile conditions and re- mained in place for 24 hours. Urine and tip catheter cultures were performed after catheter removal. RESULTS: 55 patients (38 females and 17 males) were recruited (26 total knee and 29 total hip arthroplasties). POUR was not reported in any patient, and only 1 patient (1.8%) had UTI. Cultures of catheter tips were positive in 16 patients (29.1%). Only 1 of these patients had a positive urine culture. Enterococcus faecalis was the most common pathogen isolated. None of the preoperative variables was associated with the risk of catheter colonization. CONCLUSIONS: Data from this study support early catheter removal after TJA. Predominant catheter-isolated bacteria are enteric species. The culture of a catheter tip specimen should be discouraged for the diagnosis of UTI within the frsts 24 hours after surgery. Key Words Urinary tract infection, Urinary retention, Urinary catheterization, Total joint arthroplasty Introduction Voiding problems after total joint replacement and other surgical procedures may increase mor- bidity and medical expenses 1 . Postoperative urine retention (POUR) is a well-known complication in hip (THA) and knee arthroplasty (TKA), with a variable incidence of 8% to 55% 2 . POUR does not carry a high risk of morbidity when man- aged properly 3 . However, failure to identify this condition may lead to serious clinical sequelae, such as prolonged bladder distention, urinary tract infection (UTI) and detrusor dysfunction 3 . POUR is most commonly managed using an indwelling Foley catheter or by intermittent catheterization. Previous studies compared an indwelling cathe- ter and intermittent catheterization in THA and TKA and favored an indwelling catheter because of lower bacteriuria and urinary retention rate 4 . However, indwelling Foley catheters are associat- ed with a substantial risk of UTI. UTI is directly related to the time of catheterization, and the risk was estimated at 5% to 10% per catheter-day after the frst 48 hours of catheterization 5 . The risk of mortality increases by a factor of 3 in patients with a UTI, and there is an increased risk of metastat- ic infection around joint replacements. However, the statistical signifcance of these risks remains controversial 6 . Bacteria gain access to the bladder during catheter insertion, and the pathogenesis of catheter-related urinary tract infection (CAUTI) is related to the susceptibility of the inert catheter material to microbial colonization and bioflm formation 7,8 . A bioflm on an indwelling urinary catheter consists of adherent microorganisms, their extracellular products, and host components deposited on the catheter. The bioflm lifestyle conveys a survival advantage to microorganisms because it improves the ability of microorganisms to withstand drying, shear forces, and antimicrobi- al agents. An indwelling urinary catheter generally cannot usually be cleared of a pathogenic bioflm without catheter removal 7 . Bioflm-associated or - ganisms continue to seed the urine with bacteria as long as the colonized catheter remains in place, which may cause UTI 9 . However, the risk of catheter colonization is much higher than urinary infection and positive culture of a catheter tip spec- imen is not indicative of UTI 10-12 . The commonly detected CAUTI microorganisms are members of European Review for Medical and Pharmacological Sciences A. CORIGLIANO, O. GALASSO, A. VARANO, D.A. RICCELLI, G. GASPARINI Department of Medical and Surgical Sciences, “Magna Graecia” University and “Mater Domini” University Hospital, Catanzaro, Italy Corresponding Author: Corigliano Antonio, MD; e-mail: antoniocorigliano85@gmail.com Urinary tract infections after early removal of urinary catheter in total joint arthroplasty 2019; 23(2 Suppl.): 38-42