(113) Hydrophilic Inflatable Penile Prothesis (HC-IPP) Discs Inoculated With Aerobic and Anaerobic Bacteria and Fungal Species Dipped in 0.05% Chlorhexidine Gluconate (CHG) Irrigation Solution and Irrigated With the Device to Evaluate Real World Situations
Authors: Karpman E , Griggs R , Twomey C , Henry G 
Published: May 2023

Abstract

Introduction
Hydrophilic-coated implants have significantly decreased penile prosthesis infection (PPI) since their release in 2001. However, the microbial spectrum of PPI has significantly changed. Based on recent Next Generation Sequencing literature, gram negative and fungal species are now included in the three most common organisms isolated. The Titan (Coloplast, Minneapolis, MN, USA) implant enables surgeons to choose a dipping solution according to their local biogram and preference. Irrisept (Irrimax, Lawrenceville, GA, USA) is 0.05% chlorhexidine gluconate (CHG) solution and has an extensive profile for microbial kill, including many aerobic, anaerobic, and fungal species known to cause PPI.

Objective
Evaluate microbial reduction on HC-IPP material dipped and irrigated with 0.05% CHG irrigation device using a validated microbiological study design: microbial contamination with microbial reduction counts following treatment.

Methods
An In-Vitro evaluation of the ability of an irrigation device to reduce transient bacterial contamination from a Test Substrate - pre-cut discs prepared from a HC-IPP material. Seven common PPI microorganisms - Bacteroides fragilis (A TCC #25285), Candida albicans (A TCC #10231), Enterococcus faeca/is (A TCC #29212), Escherichia coli (A TCC #25922), Pseudomonas aeruginosa (ATCC #27853), Staphylococcus aureus (ATCC #29213) and Staphylococcus epidermidis (ATCC #12228) were used for this evaluation. For each challenge species, three discs of the implant material (i.e., carriers) were pre-conditioned by immersion in 0.9% Sodium Chloride Irrigation, USP (Baseline Controls), and six discs were pre-conditioned by immersion in the test irrigation solution, (Irrisept®; Test Carriers). The pre-conditioned carriers were allowed to dry for approximately 10 minutes prior to contamination with a suspension of each test strain. Following a 2-to-3-minute drying period at room temperature, the three contaminated Baseline Carriers were evaluated for viable microbial recoveries. Three of the contaminated and dried Test Carriers were evaluated for viable microbial recoveries with no additional treatment (Pre- Rinse Test Carriers). The three remaining Test Carriers were evaluated following a rinsing procedure using 200cc of Wound Irrigation Device/Solution (Post-Rinse Test Carriers) at three time points, mimicking an in-vivo practice.

Results
Table 1 presents the Initial population (CFU/mL), Mean Baseline Control Recovery (normal saline log10) and the mean Post-Exposure Recovery (0.05% CHG log10), and Mean Post-Exposure Reduction (0.05% CHG log10) following three separate 150cc irrigations (one full bottle/disk with 0.05% CHG irrigation device. (lrrisept 450mL [Lot #21HDB982]).

Conclusions
Dipped and irrigated HC-IPP material discs with the irrigation device containing 0.05% CHG results in clinically significant log10 reductions in tested microbial strains. All previous studies on this subject matter have used zone of inhibition (ZOI) testing only. This microbiological methodology is superior as it is quantitative not qualitative, and can evaluate bactericidal, viricidal and fungicidal activity.

Disclosure
Yes, this is sponsored by industry/sponsor: Irrimax Corporation, Coloplast Corporation

Clarification
Industry funding only - investigator initiated and executed study
Any of the authors act as a consultant, employee or shareholder of an industry for: Coloplast, Irrimax.