Biofilm and Infectious Agents Present at the Time of Penile Prosthesis Revision Surgery: Times Are a Changing

Unveiling the Hidden Perils: A Comprehensive Review of Fungal Infections in Inflatable Penile Prosthesis Surgery

Inflatable penile prosthesis (IPP) surgery is an effective treatment for erectile dysfunction (ED), but infections pose a significant threat to its success. Current guidelines lack antifungal recommendations, despite rising fungal infection rates post-IPP surgery. This review examines epidemiology, risk factors (including diabetes mellitus, immunosuppression, and obesity), and pathogenesis, highlighting the role of biofilm formation in device contamination. Clinical manifestations vary from acute to delayed, with fungal biofilms presenting challenges in diagnosis. Prophylactic strategies, including broad-spectrum antibiotics and antifungals, are crucial, with evidence suggesting a 92% reduction in infections. With fungal infections showing lower salvage rates, management involves culture-guided treatment, irrigation, and oral antibiotics. Future research aims to understand biofilm mechanisms and develop biomaterials to reduce infection rates. Implementing antifungal therapy, along with standard practices like the no-touch technique and antibiotic dips, is crucial in preventing IPP infections.

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.

Partial Component Exchange of a Non-Infected Inflatable Penile Prosthesis is Associated With a Higher Complication Rate

OBJECTIVE

To describe the infectious and non-infectious complications in men undergoing Inflatable penile prosthesis (IPP) revision with partial and complete component exchange for mechanical malfunction.

METHODS

We performed a multicenter retrospective cohort study of patients who underwent IPP revision. Men undergoing procedures for implant infection were excluded. Patients were divided into those who had complete exchange of the entire device or partial exchange of only one or 2 components. Infectious and non-infectious complications were compared between groups.

RESULTS

Three hundred sixty-eight men had complete exchange of the entire device and 85 had partial component exchange. Men undergoing partial exchange had a significantly higher infection rate (7.1% vs 2.2%, P = .031). The partial exchange group also was more likely to receive antifungals (51.8 vs 16.6%, P < .001), have a modified salvage washout (77.4 vs 60.2%, P = .004), and less likely to receive vancomycin and gentamicin (63.5 vs 83.7%, P < .001). Time to revision was significantly shorter in the partial exchange group (44.9 vs 168.2 months, P < .001). Mean follow-up was slightly longer in the complete exchange group (18.3 vs 13.0 months). In multivariable analysis, partial exchange surgery, vancomycin and gentamicin prophylaxis, modified salvage washout, and antifungal prophylaxis were no longer associated with postoperative infections. The partial exchange group had greater rates of non-infectious complications (21.2% vs 9.5%, P = .005) such as pump malfunction and tubing breakage.

CONCLUSION

Patients undergoing partial component revision had more infectious and non-infectious complications. These findings suggest that partial component exchange increases complications in men undergoing IPP revision.

Timing and causative organisms associated with modern inflatable penile prosthesis infection: an institutional retrospective

BACKGROUND

The advent of antibiotic-coated devices has reduced the rate of inflatable penile prosthesis (IPP) infections; however, this may have altered microbial profiles when infections do occur.

AIM

To describe the timing and causative organisms behind infection of infection retardant-coated IPPs in the context of our institution's perioperative antimicrobial protocols.

METHODS

We retrospectively reviewed all patients undergoing IPP placement at our institution from January 2014 to January 2022. In all patients, perioperative antibiotic administration was congruent with American Urological Association guidelines. Boston Scientific devices are impregnated with InhibiZone (rifampin and minocycline), and all Coloplast devices were soaked in rifampin and gentamicin. Intraoperative irrigation was performed with betadine 5% irrigation prior to November 2016 and with vancomycin-gentamicin solution afterward. Cases involving prosthesis infection were identified, and variables were extracted from the medical record. Descriptive and comparative statistics were tabulated to identify clinical characteristics, including patient comorbidities, prophylaxis regimen, symptom onset, and intraoperative culture result. We previously reported an increased infection risk with Betadine irrigation and stratified results accordingly.

OUTCOMES

The primary outcome was time to infectious symptoms, while the secondary outcome was description of device cultures at the time of explantation.

RESULTS

A total of 1071 patients underwent IPP placement over 8 years with an overall infection rate of 2.6% (28/1071). After discontinuation of Betadine, the overall infection rate was significantly lower at 0.9% (8/919) with a relative risk of 16.9 with Betadine (P < .0001). Primary procedures represented 46.4% (13/28). Of 28 patients with infection, only 1 had no identified risk factors; the remainder included Betadine at 71% (20/28), revision/salvage procedure at 53.6% (15/28), and diabetes at 50% (14/28). Median time to symptoms was 36 days (IQR, 26-52); almost 30% of patients had systemic symptoms. Organisms with high virulence, or ability to cause disease, were found in 90.5% (19/21) of positive cultures.

CLINICAL IMPLICATIONS

Our study revealed a median time to symptoms of just over 1 month. Risk factors for infection were Betadine 5% irrigation, diabetes, and revision/salvage cases. Over 90% causative organisms were virulent, demonstrating a microbial profile trend since antibiotic coating development.

STRENGTHS AND LIMITATIONS

The large prospectively maintained database is a strength along with the ability to follow specific changes in perioperative protocols. The retrospective nature of the study is a limitation as well as the low infection rate, which limits certain subanalyses from being performed.

CONCLUSION

IPP infections present in a delayed manner despite the rising virulence of infecting organisms. These findings highlight areas for improvement in perioperative protocols in the contemporary prosthetics era.

A PEDOT nano-composite for hyperthermia and elimination of urological bacteria

Novel modalities for overcoming recurrent urinary tract infections associated with indwelling urinary catheters are needed, and rapidly induced hyperthermia is one potential solution. PEDOT nanotubes are a class of photothermal particles that can easily be incorporated into silicone to produce thin, uniform coating on medical grade silicone catheters; subsequent laser stimulation therein imparts temperature elevations that can eliminate bacteria and biofilms. PEDOT silicone coatings are stable following thermal sterilization and repeated heating and cooling cycles. Laser stimulation can induce temperature increases of up to 55 °C in 300 s, but only 45 s was needed for ablation of UTI inducing E. coli biofilms in vitro. This work also demonstrates that mild hyperthermia of 50 °C, applied for only 31 s in the presence of antibiotics could eliminate E. coli biofilm as effectively as high temperatures. This work culminates in the evaluation of the PEDOT NTs for photothermal elimination of E. coli in an in vivo model to demonstrate the safety and effectiveness of a photothermal nanocomposite (16 s treatment time) for rapid clearance of E. coli.

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.

Review of Ischemic and Non-ischemic Priapism

PURPOSE OF REVIEW

Priapism is a rare condition that has different presentations, etiologies, pathophysiology, and treatment algorithms. It can be associated with significant patient distress and sexual dysfunction. We aim to examine the most up-to-date literature and guidelines in the management of this condition.

RECENT FINDINGS

Priapism is a challenging condition to manage for urologists, since the etiology is often multi-factorial and the suggested treatment algorithms are based on small studies and expert anecdotal experience, perhaps due to the rarity of the disorder. Ischemic priapism of less than 24 h can be managed non-surgically in most cases with excellent results. Ischemic priapism of more than 36 h is frequently associated with permanent erectile dysfunction. Management of prolonged priapism with penile shunting still may result in poor erectile function, so penile prosthesis can be discussed in these scenarios.

Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices

The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.

Prevention of Penile Prosthesis Infection

INTRODUCTION

Management protocols for treatment of severe erectile dysfunction have changed little in the last 20 years. Most algorithms consider penile prostheses as the last option of treatment in patients who have failed medical management. Despite multiple advances in current devices, prosthetic infection remains the most feared complication by implanting surgeons and patients. This report tries to make a compilation of the factors that can be impacted to prevent penile implant infections, and to make penile implantation a safer and more reliable way to solve an erection deficit.

PURPOSE OF REVIEW

List events related to the surgical act (pre-operative, intra-operative, and post-operative) that are related to the risk of infection to contextualize possible actions/measures used to avoid prosthetic infection.

RECENT FINDINGS

The impact of coated implants on reduction of infection rates. The recommendation to use chlorhexidine-based solutions over iodine solution for preoperative skin preps. Appears to be no difference in infection rates according to the approach chosen by the surgeon (infrapubic vs penoscrotal). The change in the microbial colonies that are colonizing implants in recent years are dramatic. Lack of evidence of which solutions to use for salvage or revision washout surgery: Chemical eradication or mechanical lavage cleansing?. Despite the importance of metabolic control in the literature, there is a disparity in exact glycemic values ​prior to the intervention in our literature. Factors such as preparation of the operative site, presence of comorbidities or previous surgeries, surgical time, or additional maneuvers during surgery can negatively impact the final result of penile prosthetic surgery.

Is There a Role for Antifungal Prophylaxis in Patients Undergoing Penile Prosthesis Surgery? A Systematic Review

OBJECTIVE

The aim of this study is to review the literature on the use of antifungal prophylaxis in penile prosthesis (PP) surgery and provide a summary on its efficacy as an adjunct to current prophylactic regimes in patients undergoing PP surgery.

MATERIALS AND METHODS

PubMed, Medline, and EMBASE databases were systematically searched up to May 2020. All included studies were analysed and the information extracted included author, title of study, year of publication, type of study, journal of publication, and main findings regarding post PP implantation fungal infections.

RESULTS

Nine relevant studies were included in this review, comprising retrospective single-centre studies and retrospective multicentre studies ranging from 2017 to 2020. Fungal infections were found responsible for 11.1% of all PP infections, with a greater risk in patients with diabetes, obesity, and from warmer climates. Current American Urological Association (AUA) and European Association of Urology (EAU) prophylaxis guidelines do not incorporate the use of antifungals. Trials of antifungal prophylaxis regimes combined with antibiotic prophylaxis have demonstrated a reduction in PP fungal infections.

CONCLUSIONS

Fungal infections represent a significant proportion of implant infections and therefore antifungal prophylaxis is warranted. Future studies comparing the efficacy of traditional antibiotic prophylaxis as set out by AUA/EAU with novel prophylaxis regimes including the addition of an antifungal may provide more definitive guidance on this issue. Until then antifungal prophylaxis in all patients undergoing PP procedures may provide a significant cost-effect benefit.

Penile implant infection resulting in Staphylococcus aureus bacteraemia and infective endocarditis

Introduction

Penile implant infections are a possible surgical complication that has historically been most commonly associated with Gram-positive bacteria. Staphylococcus aureus is a Gram-positive bacteria and is the most common cause of endocarditis.

Case Presentation

A male patient in his 50s with a past medical history of hypertension, diabetes, end-stage renal disease (ESRD) on peritoneal dialysis (PD) and erectile dysfunction with a penile implant placed 6 years prior to the admission date presented with complaints of scrotal pain. The pump for his implant had eroded through his scrotum and was draining pus. Blood cultures returned positive for Gram-positive cocci in clusters in 4/4 bottles, which was eventually identified as methicillin-sensitive Staphylococcus aureus (MSSA). A transthoracic echocardiogram (TTE) was performed due to concern for infective endocarditis (IE) but did not show any valvular abnormalities. Due to high clinical suspicion, a transesophageal echocardiogram (TEE) was performed and revealed a vegetation on the native mitral valve. His penile implant was removed by urology and intraoperative cultures grew MSSA. Surgical valve replacement was not recommended, and the patient was sent home with IV antibiotics for 6 weeks.

Discussion

Post-operative site infections are a quite uncommon point of entry for infective endocarditis, with penile implant infections being an even rarer cause. While a TTE is often used initially to attempt to diagnose infective endocarditis, it has lower sensitivity than a TEE. If clinical suspicion for infective endocarditis remains high after negative imaging with TTE, then TEE should be performed for better visualization of the heart valves.

Penile prosthesis salvage: a historical look at the Mulcahy technique and a review of the latest literature

Historically, management of inflatable penile prosthesis infection was explantation of the device with delayed reimplantation at a later date. In 1991, this paradigm was challenged when early attempts at washout and immediate salvage proved successful. The clinical experiences and data generated over the past 30 years have allowed implanters to refine their salvage procedures to improve patient outcomes. In this article, we review the original Mulcahy technique for salvage and discuss updates to this protocol based on recent data.

Adjustable Transobturator Male System (ATOMS) Infection: Causative Organisms and Clinical Profile

OBJECTIVE

To evaluate the clinical profile and the organisms producing adjustable transobturator male system (ATOMS) infection in a contemporary series.

METHODS

Multicenter retrospective study evaluating patients undergoing ATOMS explant for clinical signs of infection from a series of 902 patients treated in 9 academic institutions. Clinical and microbiological data were evaluated.

RESULTS

Infection presented in 24 patients (2.7%). The median age was 73 ± 7yrs and the median interval from ATOMS implantation to explant 11 ± 26.5mo. Infection was diagnosed within 3-months after surgery in 7(29.2%). Scrotal port erosion was present in 6 cases (25%) and systemic symptoms of parenchymatous testicular infection in 2(8.3%). The culture of the periprosthetic fluid was positive in 20(83.3%): 12(50%) Gram-negative bacteria, 9(37.5%) Gram-positive cocci and 1(4.2%) yeast. The most frequent isolates were Enterococcus and Proteus sp. (16.7% each), followed by Pseudomona sp. and S. epidermidis (12.5% each). Methicillin resistant S. aureus was detected only in 1 case (4.2%). Despite the infection 17 patients (70.8%) were satisfied with the implant and 18(75%) received a second device (11 repeated ATOMS and 7 AUS) at a median 9.7 ± 12.6mo after explant. Limitations include retrospective design and lack of microbiological cultures in ATOMS explanted for non-infective cause.

CONCLUSION

Infection of a prosthetic device is a disturbing complication. A proportion of patients with ATOMS infection is associated to scrotal port erosion and/or parenchymatous urinary tract infection. Enterococcus and Proteus sp. are the most common organisms producing ATOMS infection and this could have implications for the selection of the most appropriate surgical prophylaxis.

Radical cystectomy and orthotopic neobladder in a patient with a preexisting three-components inflatable penile prosthesis

INTRODUCTION AND OBJECTIVES

As erectile dysfunction is more commonly being diagnosed and treated with a preexisting inflatable penile prosthesis (IPP) insertion at younger ages, surgeons will increasingly encounter pre-placed abdominal reservoirs when performing pelvic surgery.

MATERIALS AND METHODS

A 69-year-old Caucasian man with BCG refractory carcinoma-in-situ (CIS) and past history of non-invasive high-grade urothelial carcinoma of the bladder was a candidate for a radical cystectomy and an ileal-neobladder diversion. He had a three-components IPP inserted for the treatment of Peyronie disease and organic erectile dysfunction (ED). During the radical cystectomy the reservoir was encapsulated on the left lateral pelvic wall over the external iliac vessels. It was isolated and IPP was inflated to reduce the reservoir size. After accurate disinfection, the reservoir was removed from Retzius space without disconnecting it from the pump. Then, the radical cystectomy was carried out without any intraoperative complications and Studer ileal orthotopic neobladder was performed. At the end of the surgery, the reservoir was disinfected with the Mulcahy protocol and then placed in the same position.

RESULTS

A week after catheter removal the IPP was successfully activated. The patient's postoperative recovery was uneventful and no postoperative complication occurred. Definitive histological examination described a multifocal urothelial carcinoma of the bladder: pG3Tis N0 R0. The patient reports excellent functionality of the penile prosthesis and is currently using it.

CONCLUSIONS

Sexual functionality preservation in oncologic patients should be pursued when possible. In this report, the functionality of the IPP was preserved, while still performing oncologically radical procedures. A multicenter study is needed to assure more solid recommendations on this rare procedure that is surely burdened by a lot of risks.

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.

[Penile prosthesis]

The insertion of a penile prosthesis (PP) is a definitive treatment option for erectile dysfunction (ED), induratio penis plastica, after phalloplasty or priapism. The aim is a "normal" erection with the possibility of a satisfactory sexual life. The costs of the operation are covered by the health insurance. In addition, manual dexterity, concomitant diseases and possible contraindications should be considered preoperatively. While semirigid PPs are simply aligned in the desired position when used, inflatable PPs must be activated and deactivated via a pump. In addition to injury to local structures and postoperative infections, long-term complications such as mechanical implant failure or an undesirable cosmetic result may also occur. Careful patient selection and a detailed counselling and information session are therefore of decisive importance. Implantation is performed in the supine or lithotomy position via an infrapubic or penoscrotal approach. PPs should not be implanted if cutaneous, systemic or urinary tract infections are present. Inflatable PPs are preferred by most patients as they come closest to a "natural" erection. A PP offers one of the highest satisfaction rates among treatment options, regardless of indication, and is highly rated by patients and their partners across models due to product reliability. Differences between the models of the various manufacturers could not be demonstrated. The choice of prosthesis should therefore be adapted to the patient's individual requirements and health conditions.

Infected penile prosthesis: literature review highlighting the status quo of prevention and management

INTRODUCTION

Erectile dysfunction affects over 50% of men 70 years and above, and penile prosthesis (PP) is its third-line treatment. Complications of PPs include infection, however, no formal guidelines exist for its management.

METHODS

We performed a literature search and reviewed 53 recent published literatures of experiences with management of PP infections, prevention, and treatment.

RESULTS

Acute infection can present early with pain and discharge and detection of early signs is of utmost importance. MRI studies are more sensitive than CT studies to diagnose and plan surgical intervention. Introduction of antibiotic impregnated devices attributed to the reduction of infection rates with superiority proven for certain types; the no-touch technique had further reduced this rate. The Mulcahy salvage remains the most widely used surgical approach for treatment despite modifications and novel techniques described; conservative management of PP infections is recently reported with promising results.

CONCLUSIONS

Despite absence of strict guidelines for the management of infected PPs, we reviewed and discussed numerous panel opinions and suggestions throughout literature. More research into the pathology, prevention, conservative management and advances in surgical treatment of this condition are called for to produce guidelines that unite the efforts to tackle these infections.

Updates in penile prosthesis infections

Inflatable penile prostheses are an important tool in the treatment of medically refractory erectile dysfunction. One of the major complications associated with these prostheses is infections, which ultimately require device explanation and placement of a new device. Over the past several decades, significant work has been done to reduce infection rates and optimize treatment strategies to reduce patient morbidity. This article reviews the current state of knowledge surrounding penile prosthesis infections, with attention to the evidence for methods to prevent infection and best practices for device reimplantation.

Minimizing Penile Prosthesis Implant Infection: What Can We Learn From Orthopedic Surgery?

The implantation of penile protheses for the surgical treatment of erectile dysfunction has risen in popularity over the past several decades. Considerable advances have been made in surgical protocol and device design, specifically targeting infection prevention. Despite these efforts, device infection remains a critical problem, which causes significant physical and emotional burden to the patient. The aim of this review is to broaden the discussion of best practices by not only examining practices in urology, but additionally delving into the field of orthopedic surgery to identify techniques and approaches that may be applied to penile prothesis surgery.

Update on Intraoperative Cultures, Biofilms, and Modifiable Factors During Revision of Clinically Non-Infected Penile Implants

INTRODUCTION

Penile implants have a limited lifespan, and as the population using inflatable penile prostheses ages, revision surgery has become increasingly common. Devices are frequently cultured during non-infectious revision surgeries, providing a burgeoning of evidence of positive cultures without clinical infection. However, the clinical significance of these cultures remains unclear.

OBJECTIVES

We aim to review the current literature on culture results from revision surgery for clinically non-infected devices and summarize the available data to formulate a synopsis of clinically significant organisms and their significance and modifiable approaches to prosthesis surgery.

METHODS

A literature review was performed on 1 March, 2020 in PubMed and Google Scholar. Search terms centered on penile prosthesis revision surgery, cultures, and infection. Titles and abstracts were reviewed for topical relevance with emphasis placed on literature from the last 20 years. Most publications comprised small case series aside from a single meta-analysis.

RESULTS

Since 1995, seven series have been published examining culture positivity at the time of revision surgery for clinically non-infected devices. Isolated organisms are most commonly from the Staphylococcus genus with Staphylococcus epidermidis being the most frequently isolated organism on clinically non-infected devices. Reported culture positivity rates at the time of revision range between 9.8% and 80%.

CONCLUSION

Current literature pertaining to the clinical significance of culture positivity at the time of revision surgery for clinically non-infected penile prostheses is lacking; however, multiple series do report high rates of culture positivity. This does appear to confer a higher rate of subsequent infection and a lower revision-free survival. Staphylococcus epidermidis is the most commonly isolated organism followed by other members of the Staphylococcus genus. Further studies are needed to determine the impact of modifiable variables or techniques on asymptomatic culture positivity and the ideal technologies for biofilm prevention. Nosé BD, Grimberg DCD, Lentz AC. Update on Intraoperative Cultures, Biofilms, and Modifiable Factors During Revision of Clinically Non-Infected Penile Implants. Sex Med Rev 2021;9:160-168.

Comparison of Penile Prosthesis Cultures Within Individual Patients After Removal/Replacement and Subsequent Salvage

Introduction

Infection rates for virgin inflatable penile prostheses (IPPs) range from 1 to 3%; however, this can increase to 7–18% after IPP revision or removal/replacement (RR) for mechanical malfunction. Although studies have reported various RR and salvage cultures, limited data are available that directly compare microorganisms after each of these procedures within the same patient. Comparison of these cultures may determine if the infection is due to a persistent microorganism or new inoculation.

Aim

Our aim is to characterize prosthesis cultures within individual patients who develop infection after RR.

Methods

We retrospectively reviewed patients undergoing various IPP procedures at our institution from September 2002 to August 2018. RR procedures were determined by current procedural terminology codes 54,410 or 54,416. Infection, defined as salvage or explantation without replacement for infectious reasons, was described by current procedural terminology codes 54406, 54411, 54415, or 54417. Inclusion criteria consisted of IPP infection after RR and the presence of both RR and salvage cultures within the same patient. Owing to the small cohort size, only descriptive statistics were used.

Main Outcome Measures

Characterization of removal/replacement and salvage cultures is the main outcome measure of this study.

Results

A total of 202 non-infected RR procedures were performed with 9 cases (4%) of IPP infection after RR identified. Four (44%) of the RR cultures were positive and contained gram-positive (44%) and gram-negative (11%) organisms. In comparison, salvage cultures grew gram-positive bacteria (66%), gram-negative bacteria (33%), and/or fungal elements (33%). A direct comparison of the RR and salvage cultures indicated that only 2 patients (22%) grew similar organisms.

Conclusions

The risk of IPP infection after RR and modified washout is low. In this small series, gram-positive bacteria were most common at the time of RR and salvage. The increased incidence of fungal infections may indicate a need to modify RR protocols. Larger multi-institutional studies are needed to further investigate this relationship.

Chandrapal J, Harper S, Davis LG, et al. Comparison of Penile Prosthesis Cultures Within Individual Patients After Removal/Replacement and Subsequent Salvage. Sex Med 2020;8:783–787.

Risk factors associated with penile prosthesis infection: systematic review and meta-analysis

PURPOSE

The aim of this study was to identify the factors associated with infection in patients who undergo penile prosthesis implantation.

METHODS

We performed a systematic review/meta-analysis, including clinical trials, quasi-experiments, retrospective and prospective cohort studies, and case-control studies. Searching was done in CENTRAL, MEDLINE, and EMBASE databases. Participants were patients who had erectile dysfunction, regardless of the etiology, and underwent penile prosthesis implantation. Two researchers reviewed each reference by title and abstract. The statistical analysis was performed using Review Manager 5.3 (RevMan® 5.3).

RESULTS

A total of 513 studies were found with the search strategies. After excluding duplicates, 40 studies with a total of 175,592 patients were included in the qualitative and quantitative analysis. Among patient characteristics, we found that diabetes mellitus and immunosuppression appear to have increase odds of infection. Related to the procedure, infection-retardant-coated penile prosthesis and primary (first) surgery appear to lower odds of infection.

CONCLUSIONS

Diabetes mellitus and immunosuppression were associated with increased infection rates; infection-retardant coating of the prosthesis and primary surgery were associated with reduced infection rates.

The Prevalence and Treatment of Erectile Dysfunction in Male Solid Organ Transplant Recipients

INTRODUCTION

Erectile dysfunction (ED) is a prevalent and under-recognized complaint among male solid organ transplant recipients. Most research on this topic has focused on kidney transplant recipients alone. In this review, we integrate current research on ED across all types of solid organ transplant recipients and assess the success of current methods of ED treatment in transplant populations.

AIM

To review the current literature addressing the prevalence and treatment of ED in the male solid organ transplant population.

METHODS

A literature search was conducted using PubMed to identify relevant studies. Search terms included "organ transplant" and "erectile dysfunction." Titles and abstracts were reviewed for relevance. References from identified articles were also searched and included, if appropriate.

MAIN OUTCOME MEASURES

Review of peer-reviewed literature.

RESULTS

The prevalence of ED among transplant recipients is higher than that in the general population: 39.8-86.2% in liver transplant recipients, 54-66% in renal transplant recipients, 71-78% in heart transplant recipients, and 79% in simultaneous pancreas-kidney transplant recipients. Phosphodiesterase-5 inhibitors have up to 80% efficacy in treating ED in kidney transplant recipients. Intracavernosal injections have been used with success rates of 60-70% in cardiac and renal transplant recipients. Penile prostheses have also been shown to be safe and effective across transplant types. A low incidence of infection has been reported in several case series, although there is concern for an increased rate of mechanical complications in pelvic organ transplant recipients. Accordingly, placement of a two-piece or malleable prosthesis or ectopic reservoir placement with a three-piece inflatable prosthesis is suggested in this population.

CONCLUSION

ED is highly prevalent among male solid organ transplant recipients and should be routinely screened in this population. Current modalities of ED treatment used in the general population are safe and effective in solid organ transplant recipients, although success rates are often lower than those in the general population. Payne K, Popat S, Lipshultz LI, et al. The Prevalence and Treatment of Erectile Dysfunction in Male Solid Organ Transplant Recipients. Sex Med Rev 2021;9:331-339.

The Effect of Bupivacaine on the Efficacy of Antibiotic Coating on Penile Implants in Preventing Infection

Background

In an effort to reduce dependence on opioids following inflatable penile prosthesis placement, intra-operative soaking of the implant in Bupivacaine (BUP) has been proposed as part of a multimodal approach to pain control. However, no study has shown if the addition of BUP affects the antimicrobial properties of InhibiZone on AMS700 (Boston Scientific, Marlborough, MA) and/or of antibiotic soaked Titan Coloplast (Coloplast Corporation, Minneapolis, MN).

Aim

To determine if BUP alters the zone of inhibition (ZOI) against Staphylococcus epidermidis (S epidermidis) and Escherichia coli (E coli), common gram-positive and gram-negative bacterial causes of infection, respectively, created by InhibiZone coated AMS and/or by antibiotic-soaked Coloplast implant.

Methods

S epidermidis and E coli were spread on agar plates. After a 30-minute incubation, four AMS with InhibiZone strips treated with sterile saline or BUP (1.25 mg/mL) were placed on a plate. 4 Coloplast strips were dipped in varying routinely used concentrations of Rifampin (0–10 mg/mL) plus Gentamicin (0–1 mg/mL; rifampin and gentamicin (R+G)) solution with or without BUP. The ZOI for AMS with InhibiZone and Coloplast dipped in antibiotic solution was measured using ImageJ software. Normalized ZOI was calculated as (ZOI area/plate area) × 100. Unpaired t-test compared the mean ± SD ZOI between BUP and no BUP groups (n = 4/group).

Outcomes

The primary outcome of the study was the ZOI against E coli and S epidermidis at 24 and 48 hours.

Results

Growth of both S epidermidis and E coli at 24 and 48 hours of incubation was inhibited in both implants and the addition of BUP did not alter the ZOI. Coloplast strips dipped in R+G produced a ZOI in a dose-dependent manner. Interestingly, the ZOI against S epidermidis compared to that of E coli was much wider for both implants.

Clinical Implications

This suggests that the use of BUP does not affect the protective effects of antibiotic dips and can potentially be used during penile prosthesis surgery pending clinical trials.

Strengths and Limitations

This is the first study to evaluate the effect of BUP on anti-bacterial dips. As with all in vitro analysis, further research must be done to see if these findings hold true in the clinical setting.

Conclusions

The addition of BUP does not impede the in vitro antibacterial activity of InhibiZone-coated AMS or R+G-soaked Coloplast. Whether these in vitro findings translate to surgical outcomes needs to be evaluated in future preclinical trials.

Lokeshwar SD, Horodyski L, Lahorewala SS, et al. The Effect of Bupivacaine on the Efficacy of Antibiotic Coating on Penile Implants in Preventing Infection. J Sex Med 2019;7:337−344.

A Surgeon's Guide to the Various Antibiotic Dips Available During Penile Prosthesis Implantation

PURPOSE OF REVIEW

Inflatable penile prosthesis (IPP) is a treatment for erectile dysfunction. IPPs have undergone improvements; however, post-surgical infections still occur. Furthermore, the type of pathogens infecting the implants has changed recently from Gram-positive to Gram-negative bacteria and fungi due to advances in antibiotic dips targeting the skin flora. To protect against infection, the AMS 700 is pre-coated with InhibiZone (mixture of Rifampin/Minocycline) and the Coloplast Titan, with several antibiotic dip options of differing efficacies. This review discusses strategies to decrease the infection rates in implant surgery, focusing on antibiotic dips.

RECENT FINDINGS

Current research endorses the use of rifampin/gentamicin as the most studied combination; however, some studies have utilized different dips for additional coverage including the InhibiZone on the AMS 700. With the increasing prevalence of diabetes and Gram-negative organisms, there is a need to develop strategies for increased coverage against infections. Controlled studies with different antibiotic combinations are needed to identify the ideal cocktail to decrease infection.

Infection Retardant Coatings Impact on Bacterial Presence in Penile Prosthesis Surgery: A Multicenter Study

OBJECTIVE

To investigate patients for positive culture rates with or without infection retardant coatings (IRC) penile prostheses (PPs) and to examine changes in culture positive isolates found in patients presenting overt clinical infection.

METHODS

Cultures were obtained from PPs immediately upon surgical exposure of the pump. 236 patients were broken down into 2 groups, with each further divided into 2 groups. The noninfected group included 208 patients: 133 with uncoated PPs and 75 with IRC implants. The infected group included 28 patients: 16 with uncoated PP and 12 with IRC inflatable penile prostheses (IPP). Additionally, sensitivity to the combination of tetracycline and rifampin were evaluated on all cultures.

RESULTS

In the noninfected group, culture positive isolates were found in 85 patients with uncoated PP's and in 32 patients with IRC implants [P value = 0.0003]. Cultures positive for Staphylococcus genus were found in 75 uncoated PP patients, while 20 patients with IRC implants had an isolate of this genus. In the infected group, culture positive isolates were found in 7 patients with uncoated PP and 6 patients with IRC IPPs [P value = 1.000]. Positive cultures for Staphylococcus genus were found in 6 patients with uncoated PP, while 3 patients with IRC IPP had an isolate of this genus. All bacterial isolates were sensitive to the combination of tetracycline and rifampin.

CONCLUSION

Positive bacterial cultures have been shown to be present on clinically uninfected IPPs at time of revision surgery. Culture isolates grown from patients with IRC IPPs reveal a nontraditional bacterial profile: fewer cultured isolates of Staphylococcus genus.

The Impact of Immediate Salvage Surgery on Corporeal Length Preservation in Patients Presenting with Penile Implant Infections

PURPOSE

Removal of an infected penile implant often results in corporeal fibrosis, irreversible penile shortening and dissatisfaction with future implant surgery. Salvage surgery may avoid these problems but to our knowledge no study to date has evaluated these specific end points. We evaluated patients who presented to our center with an infected implant to determine the impact of salvage surgery on penile length.

MATERIALS AND METHODS

We evaluated consecutive patients undergoing removal of an infected penile prosthesis with immediate salvage or delayed reimplantation using a comprehensive, prospective database. Total corporeal length prior to and following immediate salvage or delayed reimplantation were compared. The impact of patient age, comorbidities, bacterial species, initial penile length and time to reimplantation on subsequent total corporeal length was evaluated.

RESULTS

The cohort consisted of 40 patients. Overall 81% of salvaged cases were successful, resulting in a mean 0.6 cm (95% CI 0.20 to 1.1) reduction in total corporeal length. Delayed reimplantation resulted in a mean 3.7 cm (95% CI 2.9-4.5) total corporeal length loss. In patients who underwent delayed reimplantation the total corporeal length reduction was directly proportionate to the initial penis size of the patient. No statistically significant impact on penile length was attributable to patient age, diabetes, bacterial species or time to reimplantation.

CONCLUSIONS

When possible, salvage surgery should be offered to patients with an infected penile implant. Our data confirmed that successful salvage surgery preserves penile length. When a device is explanted and replaced at a later date, patients can expect to lose 15% to 30% of penile length irrespective of age, diabetes, type of infecting organism and time to reimplantation.