Updates in penile prosthesis infections

Management of Infections Associated with Penile Prostheses and Artificial Urinary Sphincters

Prosthetic urology can substantially enhance the quality of life for patients. However, it is not without challenges. Infections of penile prostheses and artificial urinary sphincters are often difficult to diagnose, manage, and treat. Over time, device improvements, refined surgical methods, better understanding of microbiology, and biofilms in combination with higher sterility standards and protocols, have significantly reduced the rates of infection. Here, the authors offer a comprehensive overview of prosthetic urologic infections and their management in the current era.

Outcomes related to penile prosthesis reservoir removal: a 7-year multi-institutional experience

BACKGROUND

The 3-piece inflatable penile prosthesis (IPP) is the most widely used device for erectile dysfunction refractory to medications, containing a reservoir inserted into the retropubic space (RPS) or an alternative/ectopic space (AES). Indications for removal of the reservoir include malfunction, malposition, or infection. In revision cases without infection, reservoir removal is sometimes optional.

AIM

We reviewed outcomes and complications related to reservoir removal from a large multi-institutional series.

METHODS

We retrospectively reviewed databases at 6 institutions over 7 years. Patients with artificial urethral sphincter, urethral sling, or mini-jupette were excluded.

OUTCOMES

Outcomes and complications related to IPP reservoir removal were analyzed. Data were collected, but only reservoir-related complications at surgery were included. Data were compared between the RPS and AES cohorts to evaluate differences with a χ2 test, with significance at P < .05.

RESULTS

Of 215 cases, there were 172 RPS and 43 AES reservoirs. The mean patient age was 65.3 years. An overall 131 procedures were due to malfunction and 49 to malposition of an IPP component; 35 were secondary to infection. Among those retained (n = 44), reasons included reuse, avoiding surrounding structure damage, and difficult dissection. Among those removed (n = 171), 15 required a counterincision. To determine the statistical difference between those removed from the RPS and an AES, the χ2 test result was P = .00059, indicating a significant difference in the need for a counterincision between the groups. Complications included bladder perforation (n = 1) in the RPS group and an avulsion of the epigastric vessels requiring abdominal exploration (n = 1) in the AES group. To determine the statistical difference between RPS and AES complications, the χ2 test result was P = .365, indicating no significant difference between the groups.

STRENGTHS AND LIMITATIONS

Strengths include being a multi-institutional study with high-volume skilled implanters. Limitations include being a retrospective review, with implanters exclusively performing penoscrotal incisions and not utilizing an infrapubic approach. Last, there was a lack of long-term follow-up with these patients.

CONCLUSIONS

Removal of an IPP reservoir remains safe, with few intraoperative complications. Surgeons should be aware of the inferior epigastric vessels during removal in an AES or be willing to perform a counterincision to avoid injury to surrounding structures. Surgeons should also obtain preoperative imaging to identify the specific location of the reservoir and adjacent anatomy. This is the first multi-institutional study reviewing outcomes related to reservoir removal during IPP revision or removal surgery.

Does time of intraoperative exposure to the aerobiome increase microbial growth on inflatable penile prostheses?

Inflatable penile prosthesis (IPP) implantation is a surgical approach for the management of erectile dysfunction (ED). A feared complication is IPP infection, and increased operative time is a risk factor for infection. Exposure of an IPP implant to ambient air in the operating room (OR aerobiome) is thought to contribute to risk of infection from increased operative time, but this is not well-supported. The objective of this study was to evaluate if exposure to the OR aerobiome increased microbial colonization of IPPs. This was an ex vivo study using an uncoated IPP, observing standard surgical sterility and OR conditions. A sterile swab was collected every 30 min for 3 h from each IPP component. Positive controls consisted of swabs exposed to unprepped scrotal skin during in-office vasectomies. All swabs underwent quantitative polymerase chain reaction (qPCR) and next generation sequencing (NGS). Bioinformatic processing was carried out and taxonomic assignment was performed. No microbial growth was detected on any component of the IPPs at any time point, while positive control swabs all detected various skin flora, including bacterial and fungal growth. These findings suggest that exposure to the OR aerobiome does not increase the risk of IPP microbial colonization, at least within a 3-hour period. Further in vivo studies are needed.

Emerging strategies for the prevention of bacterial biofilm in prosthetic surgery

Penile prosthesis implantation is an effective treatment for erectile dysfunction (ED) with high patient satisfaction and effectiveness. Unfortunately, infections remain a dreaded complication, often necessitating device removal and imposing a substantial healthcare cost. Biofilms are communities of microorganisms encased in a self-produced polymeric matrix that can attach to penile prostheses. Biofilms have been demonstrated on the majority of explanted prostheses for both infectious and non-infectious revisions and are prevalent even in asymptomatic patients. Biofilms play a role in microbial persistence and exhibit unique antibiotic resistance strategies that can lead to increased infection rates in revision surgery. Biofilms demonstrate physical barriers through the development of an extracellular polymeric substance (EPS) that hinders antibiotic penetrance and the bacteria within biofilms demonstrate reduced metabolic activity that weakens the efficacy of traditional antibiotics. Despite these challenges, new methods are being developed and investigated to prevent and treat biofilms. These treatments include surface modifications, biosurfactants, tissue plasminogen activator (tPA), and nitric oxide (NO) to prevent bacterial adhesion and biofilm formation. Additionally, novel antibiotic treatments are currently under investigation and include antimicrobial peptides (AMPs), bacteriophages, and refillable antibiotic coatings. This article reviews biofilm formation, the challenges that biofilms present to conventional antibiotics, current treatments, and experimental approaches for biofilm prevention and treatment.

A multicenter investigation examining timing of penile prosthesis infection management and responsible organisms

The purpose of this investigation was to examine the timing of penile prosthesis infection management by different responsible organisms. A retrospective cohort study was performed of patients who underwent penile prosthesis salvage or explant procedures due to a suspected infection between 2001 and 2018. The cohort consisted of 216 patients from 33 different facilities and six countries. The most common primary organisms responsible for device infections included, Gram-positives (31.5%), no growth cultures (30.6%), Gram-negatives (22.2%), fungal (11.6%), and anaerobic organisms (4.2%). Overall, median time to infection was 1.8 (interquartile range [IQR]: 1.0-3.0) months for all patients. Median time to infection management was similar between responsible organisms: 1.0 (IQR: 1.0-2.3) months for Gram-negatives and 2 months for Gram-positives (IQR: 1.0-1.4), fungal (IQR: 1.0-5.0), anaerobes (IQR: 1.0-2.5), and no growth cultures (IQR: 1.0-3.0, p = 0.56). Median time to infection management was significantly shorter among patients who received aminoglycoside/vancomycin prophylaxis (1.5 months, IQR: 1.0-2.5, p < 0.01) compared to other antibiotic groups. Median time to infection management was significantly longer for patients managed with a three-piece inflatable implant salvage procedure (2.8 months, IQR: 1.0-5.0, p = 0.02) compared to other salvage procedures. Conventional wisdom surrounding early versus late penile prosthesis infections should largely be abandoned. More than half of penile prosthesis infections are surgically managed within 2 months of initial device placement.

Gender-affirming care in urology: emergency care of the gender-affirming surgical patient-what the primary urologist needs to know

OBJECTIVE

To present a narrative review of fundamental information needed to manage postoperative complications in patients who have undergone genital gender-affirming surgery (GAS).

METHODS

A narrative review was performed using the following keywords: 'gender-affirming surgery', 'complications', 'emergency', 'postoperative'. Articles were included after being reviewed by two primary authors for relevance. Four clinicians with significant experience providing both primary and ongoing urological care to patients after GAS were involved in article selection and analysis.

RESULTS

The most common feminising genital GAS performed is a vaginoplasty. The main post-surgical complications seen by urologists include wound healing complications, voiding dysfunction, postoperative bleeding, vaginal stenosis, acute vaginal prolapse and graft loss, rectovaginal fistula, and urethrovaginal fistula. The most common masculinising genital GAS options include metoidioplasty and phalloplasty. Complications for these surgeries include urethral strictures, urethral fistulae, and urethral diverticula. Penile implants may also accompany phalloplasties and their complications include infection, erosion, migration, and mechanical failure.

CONCLUSION

Genital GAS is increasing, yet there are still many barriers that individuals face not only in accessing the surgeries, but in receiving follow-up care critical for optimal outcomes. Improved education and training programmes would be helpful to identify and manage postoperative complications. Broader cultural level changes are also important to ensure a safe, gender-inclusive environment for all patients.

Recent technological development of penile prosthesis: a literature review

Background and Objective

In contemporary Urology, the gold standard for treatment of erectile dysfunction refractory to medical therapy has been implantation with a penile prosthesis. The past 40 years has witnessed evolutions in technology and surgical techniques, which have led to increased patient satisfaction rates and decreased complication and infection rates. This review is an update to a prior review article that evaluates these advancements in the context of patient satisfaction and different rates of complications following surgeries. In addition, the review compares malleable and inflatable prostheses with regard to infection rate, mechanical failure rate, and erosion rate.

Methods

A literature search was conducted using Medline and Google Scholar to examine papers from 1973 to the present day. Keywords, such as, "penile prosthesis surgery", "malleable penile prosthesis", "inflatable penile prosthesis", "two-piece Inflatable Penile Prosthesis (IPP)", and "three-piece IPP" were utilized during the search. A total of 76 papers were included, and all were in English.

Key Content and Findings

Studies on the latest models of each of the three prostheses (malleable, two-piece IPP, three-piece IPP) revealed patient satisfaction ratings at or above 75%. Both types of IPPs were associated with greater satisfaction and lower erosion rates while malleable prostheses were associated with lower mechanical failure rates. Although no significant differences in infection rates were noted between the prosthesis types, a history of diabetes, obesity, and smoking were predictive of infection events.

Conclusions

The three-piece IPP, if indicated for a suitable patient, is generally accepted as the best type of prosthesis given its biological mimicry to an erect human penis.

Patient selection, counseling and preparation for penile prosthesis

The penile prosthesis has revolutionized the management of erectile dysfunction and is a mainstay in the treatment of this clinical entity. The goal of proper patient selection and counseling is to achieve a satisfactory outcome for the patient. Most patients receiving a penile prosthesis are satisfied with their outcome, and while the penile prosthesis generally allows for high satisfaction rates, avenues for dissatisfaction can arise. Our aim is to aid the prosthetic urologist in identifying such avenues by discussing what factors can lead to a dissatisfied patient. Even a technically successful surgical outcome in the improperly counseled patient can have negative consequences for the patient and the patient-physician relationship. Satisfaction in the penile prosthesis arena can be variably defined and viewed from different perspectives. As such, establishing a personalized framework of expectation management, even in the patient who poses challenging factors, is paramount in preparation for penile prosthesis implantation.

Evaluation of Bacteria in a Novel In Vitro Biofilm Model of Penile Prosthesis

BACKGROUND

Delayed infection, thought to be due to gradual biofilm formation, remains a feared complication after inflatable penile prosthesis (IPP) insertion. Understanding and preventing biofilm formation is necessary to prevent infections.

AIM

To develop an in vitro model and compare growth of biofilm by different bacteria on IPPs and evaluate the anti-infective efficacy of the Coloplast Titan and AMS 700 InhibiZone.

METHODS

Sterile IPPs (Coloplast) were cut into rings and incubated with S. epidermidis, S. aureus, P. aeruginosa, A. baumannii, or K. pneumoniae cultures in tryptic soy broth (TSB) (4 hour) to ensure adequate bacteria attachment, and then in only TSB (120 hours) to allow for biofilm formation. Rings were fixed with ethanol and biofilm measured by spectrophotometer (OD570) after crystal violet staining. This methodology was repeated for S. epidermidis and P. aeruginosa with Coloplast rings dipped in 10 ml of a 10 mg/ml Rifampin, 1 mg/ml Gentamicin, and deionized water solution and undipped AMS InhibiZone rings. Crystal violet assay (OD570) was repeated after incubation within bacteria (2 hour), and then only TSB (120 hours).

OUTCOMES

The primary outcome of the study was OD570 readings, indirectly measuring biofilm mass on implant rings.

RESULTS

S. epidermidis, S. aureus, A. baumannii, P. aeruginosa, and K. pneumoniae all formed significant biofilm. P. aeruginosa showed the strongest predilection to grow biofilm on IPPs. P. aeruginosa also formed significant biofilm on antibiotic-treated Coloplast and AMS rings, while S. epidermidis was inhibited. No significant difference was found in biofilm inhibition between the implants.

CLINICAL TRANSLATION

Our findings suggest gram-negative bacteria may form biofilm more proficiently and quickly on IPPs than gram-positive organisms. Commonly used antibiotic treatments on IPPs may be effective against S. epidermidis but not against P. aeruginosa biofilm formation.

STRENGTHS & LIMITATIONS

This is the first study comparing biofilm formation by different bacteria organisms on IPPs and the inhibitive ability of Coloplast and AMS implants against biofilm formation. Clinical data on organisms responsible for infected IPPs is needed to determine the clinical relevance of our findings.

CONCLUSION

Our novel in vitro model of biofilm formation of IPPs evaluated the effect of a gentamicin/rifampin antibiotic dip on Coloplast Titan implants and the anti-infective capacity of the minocycline/rifampin precoated AMS 700 InhibiZone against S. epidermidis and P. aeruginosa. P. aeruginosa was able to grow on both antibiotic-treated implants, with no significant difference, and should continue to be a specific target of investigation to reduce delayed post-operative IPP infections. Narasimman M, Ory J, Bartra SS, et al. Evaluation of Bacteria in a Novel In Vitro Biofilm Model of Penile Prosthesis. J Sex Med 2022;19:1024-1031.

Intraoperative use of vancomycin paste during penile prosthesis placement: initial outcomes

Penile prosthesis implantation is a safe and effective treatment option in the management of erectile dysfunction, associated with high satisfaction and low complication rates. Infection is a rare complication (0.5-3%), but devastating for the patient and surgeon when it occurs. Adapting from other surgical disciplines, we have utilized vancomycin paste to provide prolonged focal antibiotic exposure around the penile prosthesis pump, a site prone to infection. The aim of this study is to determine the safety and efficacy of intraoperative vancomycin paste with regards to infection prevention during penile prosthesis placement. This is a multi-institutional nonrandomized retrospective IRB-approved study comparing patients who underwent placement of a primary inflatable penile prosthesis with intraoperative vancomycin paste to those without. Primary outcomes included pump fibrosis, infection, erosion, hematoma, and complete device malfunction. From April 2019 to October 2019, two surgeons utilized vancomycin paste intraoperatively during virginal penile prosthesis surgery on 90 patients, whose mean age was 60 years. These patients were compared to an historical control group that included 166 patients, also with a mean age of 60 years, who underwent the same penile prosthesis surgery between 2014 and 2017 without the paste. Among the intervention group, the overall complication rate was 1.1%, due to a scrotal hematoma. Ultimately, there was no statistically significant difference in infection rate (0% in both groups) or overall complication rate (1.1% in the intervention group compared to 1.2% in the control group). The use of vancomycin paste appears to be safe, however future prospective studies are needed to determine its efficacy in infection prevention.

Penile implant surgery-managing complications

Penile prosthesis surgery represents the end-stage treatment for erectile dysfunction. It is conventionally used only in cases of erectile dysfunction refractory to pharmacological treatments or vacuum constriction devices. Contemporary literature suggests that penile prothesis surgery is associated with a high satisfaction rate and a low complication profile. However, it must be appreciated that the complications of surgery can have devastating consequences on a patient’s quality of life and satisfaction and include infection, prosthesis malfunction, penile corporal perforation and penile length loss. Several factors – such as appropriate patient selection, methodical preoperative assessment and patient optimization, specific intraoperative protocols and postoperative recommendations – can reduce the risk of surgical complications. This narrative review discusses the diagnosis and management of both intraoperative and postoperative complications of penile prosthesis surgery.

Narrative review of penile prosthetic implant technology and surgical results, including transgender patients

Over the past 40 years, the technological and surgical advancements in penile prostheses have led to increased patient satisfaction rates and decreased complication and infection rates. In cis males with erectile dysfunction (ED), these technological improvements tremendously improve quality of life. In female to male transgender patients, prostheses provide the ability to engage in penetrative intercourse and to urinate standing. This review evaluates technological and surgical advancements in penile prosthetics in the context of documented patient satisfaction and complication rates from prosthesis surgeries. Retrospective studies of penile implant usage in female to male gender-affirming surgeries report that infection and complication rates are higher than those seen in cis males. There are newer prostheses developed specifically for female to male reassignment surgeries, but outcome data is limited. Continued research and development are needed to develop more efficacious penile implantation options for gender affirmation surgery.

Red man syndrome caused by intracavernous irrigation with vancomycin at the time of placing penile implants

To the Editor, Erectile dysfunction is a condition that affects more than half of men between 40 and 70 years of age. Penile prosthesis (PP) implant is recognized, at present, as the most effective option to obtain an artificial erection satisfactory for sexual intercourse in those patients in which the pharmacological approach is contraindicated or ineffective. [...].

Multicenter surgical outcomes of penile prosthesis placement in patients with corporal fibrosis and review of the literature

Penile prosthesis (PP) insertion in the setting of corporal fibrosis can be challenging and a variety of techniques have been described to accomplish this, however the necessity of these maneuvers is debatable. Our objective was to investigate techniques and outcomes of PP placement in patients with corporal fibrosis at tertiary referral centers. Multicenter outcomes of 42 patients (mean age 53.4 ± 1.9 years) with corporal fibrosis who underwent placement of PP over a 10-year period were reviewed. The most common etiology of corporal fibrosis was prior PP explant due to either infection (40.5%) and/or erosion (16.7%). Fourteen patients (33.3%) had a history of priapism, 5 (11.9%) of which had one or more distal surgical penile shunts. Techniques used for PP placement included: sequential dilation (8-12 mm) with standard dilators in 15 (35.7%), dilation with cavernotomes in 25 (59.5%) and limited sharp corporal excision and dilation with cavernotomes in 1 (2.4%). Narrow cylinders were employed in ten patients (23.8%). Major complications occurred in one patient (2.4%) who underwent explant for infection and distal erosion. Most patients with corporal fibrosis can undergo successful placement of a PP using standard dilators or cavernotomes. Sharp corporal excision and other measures are rarely required.