Abstract Introduction Inflatable penile prostheses (IPPs) are a definitive treatment for refractory erectile dysfunction, but infection remains a significant complication. Infection-retardant (rifampicin-minocycline) and hydrophilic polyvinylpyrrolidone coatings, have been developed to mitigate this risk. Antimicrobial solutions like vancomycin-gentamicin (VG) and 0.05% chlorhexidine gluconate (CHG, recently in the form of Irrisept) are commonly used for device dipping and irrigation, yet conflicting in-vitro studies have created uncertainty about their comparative efficacy. Objective This review aims to analyse the microbiological principles and methodological challenges in the currently available pre-clinical studies of antimicrobial solutions for IPPs. Methods A literature review was conducted on PubMed and Embase (January 5, 2025) and Boolean-operators were used to refine the search, with inclusion criteria limited to English-language, full-text in-vitro studies focusing on infection-related properties of prosthetics. Clinical studies and those addressing non-infection-related characteristics were excluded. The review team, including a microbiologist, critically analysed methodologies from studies, including microbial selection, biofilm assessment, and antimicrobial efficacy testing (zone of inhibition assays, colony-forming unit quantification). Special attention was given to the experimental designs of Karpman et al. and Simhalet al., which employed divergent approaches to evaluate CHG and VG solutions. Results A total of 54 studies were reviewed. The review highlighted the polymicrobial nature of IPP infections, with gram-positive bacteria predominating alongside gram-negative pathogens and fungi. Karpman et al. tested Irrisept against seven microorganisms, reporting significant reductions in bacterial load after dipping and irrigation. In contrast, Simhal et al. focused on Methicillin sensitive S.aureus and found VG solutions superior to Irrisept, particularly when implants were pre-treated. Significant methodological differences were found between studies, specifically microbial inoculum quantity, treatment sequence, and assessment techniques thus rendering comparison between studies challenging. Conclusions The contrasting conclusions of the Karpman and Simhal studies underscore the complexity of evaluating antimicrobial solutions for IPPs, but this review highlights the need for a consensus approach as to how such studies are conducted. Disclosure No
Katz-Summercorn et al. (Mon,) studied this question.