**10. Biofilm management**

As mentioned above, a general feature of the microorganisms that form the bio-membranes is their resistance to various antimicrobial substances, as opposed to free-flowing cells. The main objective should prevent biofilm formation by the prophylactic administration of antibiotics and strict adherence to antisepsis rules when attaching any prosthetic material and in this case a catheter. It is also proposed to incorporate antimicrobial agents into the material to be implanted and to modify the physical or chemical properties of the material so as not to favor biofilm formation.

To achieve satisfactory penetration of antimicrobial drugs into the bio-membrane, experimentally liposomal forms of drugs have been tested with encouraging results. Reid et al. claimed that the daily use of cranberry helmet juice drastically reduced the formation of biofilm and reduced the adhesion of Gram-negative and -positive microorganisms to bladder cells [84]. Respectively, in more recent studies and post-analysis, the clinical benefit of using cranberry juice to reduce urinary tract infections appears to be limited to recurrent urothelial infections in women without neurogenic urinary disorders of young and middle age [85, 86].

The use of antimicrobial drugs for the prevention of UTIs in people who have intermittent catheterization or carry an indwelling bladder catheter has some positive results. In some studies, prophylactic antibiotics are reported to be effective. The use of methenamine orally and intake of acidic substances contributes to the reduction of urinary tract infection in the case of intermittent catheterization [87]. A low dose of ciprofloxacin appears to be more effective than placebo in preventing urinary tract infection [88]. In a study, administration of the 500 mg twice daily dose for 10 days reduced the incidence of Gram-negative organisms in the perineum and urethra but ciprofloxacin-susceptible microorganisms were replaced by resistant microorganisms such as staphylococci, including methicillin-resistant *S. aureus*, Enterococci and Acinetobacter spp. [89]. In contrast to the above, comparative studies of prophylactic administration of ascorbic acid, TMP-SMX, nalidixic acid, methenamine hippurate, or nitrofurantoin microcrystals to prevent urinary tract infection in patients with SCI did not provide statistically significant results. In a daily use of TMP-SMX study compared to placebo as a prophylaxis for urinary tract infections in SCI patients, the use of TMP-SMX did not reduce the incidence of symptomatic bacteremia while there was an increase in TMP-SMX resistance in asymptomatic patients [90].
