Bacterial Colonization and Biofilm-Associated Phenotypes in Selected Urinary Devices from Hospitalized Patients in Egypt

Abstract

Background: Retrieved urinary devices may harbor bacterial and fungal communities attached to their surfaces. Colonization of a device is distinct from symptomatic catheter-associated urinary tract infection. This study describes the organisms cultured from urinary devices selected because adherent material was visible and illustrates the laboratory approaches used to characterize associated biofilms. Methods: A hospital-based descriptive series included 130 retrieved urinary devices bearing macroscopically or microscopically visible adherent material. The collection comprised two-way silicone Foley catheters (n = 40), two-way rubber Foley catheters (n = 50), three-way silicone Foley catheters (n = 15), suprapubic catheters (n = 6), and ureteric/Double-J stents (n = 19). cultures, phenotypic identification with VITEK 2, crystal-violet microtiter and qualitative adherence assays, scanning electron microscopy and ica-targeted PCR were described. Antimicrobial susceptibility testing was also performed on subsets of isolates. Results: Growth was reported from all 130 devices included after selection for visible adherent material. Described species included Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Staphylococcus epidermidis. The images document representative surface deposits, assay appearances, scanning electron micrographs and PCR fingerprint patterns. AST isolate totals were reported for E. coli (n = 43), P. mirabilis (n = 3), P. aeruginosa (n = 13) and S. epidermidis (n = 37). Isolate-by-device counts, individual crystal-violet measurements, gene-specific PCR assignments and agent-level susceptibility counts were not available for quantitative analysis. Conclusions: This selected series demonstrates culture recovery of bacteria from urinary devices bearing visible adherent material and documents complementary laboratory images of biofilm-associated phenotypes. The selected sample cannot estimate device-colonisation prevalence or catheter-associated urinary tract infection incidence; the available susceptibility information does not establish organism-specific resistance rates.