RAPISARDA Viviana Andrea
congresos y reuniones científicas
PHENOTYPIC CHARACTERIZATION OF UROPATHOGENIC ISOLATES FROM CONTAMINATED URINARY CATHETERS
CASTAGNARO, E; VILLEGAS, J M; RAPISARDA, VA; FARIZANO, JV; GRILLO PUERTAS, M
Congreso; SAIB-SAMIGE Joint meeting 2021; 2021
The ability of pathogens to adhere and form biofilms in medical devices is a relevant issue. Urology is one of the main fieldsin which biofilm can become a serious problem, specifically in catheter-associated urinary tract infections (CAUTI). Often themain strategy against CAUTI is catheter removal and replacement. However, this could lead to additional complications suchas the detachment of the biofilm from the device that would cause the spread of uropathogens (UP) to non-colonized sites. Thebiofilm formation ability varies in every single UP isolates. Therefore, it is important to extend the study of UP of medicaldevices in order to understand their behavior and design new detection protocols, appropriate antibiotic treatments andconsequently avoid the severity, persistence and spread of infections. The aim of this study was to perform the phenotypiccharacterization of UP isolates obtained from catheters removed of patients without primary symptoms of urinary tractinfection. A total of 26 UP isolates were collected from 9 catheters. Following their isolation and identification; biofilmformation patterns (BFP), colony morphology, motility, hemolytic capacity, and antibiotic susceptibility was analyzed in allthe isolates. 20 out of 26 UP isolates (76.9%) were able to form biofilm either in M63 or McConkey medium; among them, 2isolates showed a robust BFP, 7 isolates a strong BFP, 4 isolates a moderate BFP, and 7 isolates a weak BFP. Kinetic of biofilmformation showed that most of biofilm forming isolates increased their BFP from 24 to 96 h in both media. The expression ofcurli fimbriae and cellulose was observed in approximately 70% of the isolates, denoted by the rdar, pdar, ras, bdar and basmorphotypes. Among antibiotics tested, Imipenem and Amikacin were the most effective ones, being 90% and 72% of theisolates sensitive, respectively. The less effective antibiotics were ciprofloxacin and nalidixic acid. Approximately 30% of theisolates showed multi-resistance. Interestingly, a correlation between a high biofilm formation capacity and antibioticresistance was observed. In addition, 61% of the isolates presented hemolysis capacity. This preliminary description of theisolates is relevant as an insight in the CAUTI field that would constitute progress in the knowledge of clinical isolates, theirphysiology and interaction in clinical settings. Data would contribute to the understanding of biofilm formation in medicaldevices.