Multicenter Investigation of Fungal Infections of Inflatable Penile Prostheses

Martin S. Gross MD; Lael Reinstatler MD, MPH; Gerard D. Henry MD; Stanton C. Honig MD; Peter J. Stahl MD; Arthur L. Burnett MD, MBA; Pedro P. Maria DO; Nelson E. Bennett MD; Bruce R. Kava MD; Tobias S. Kohler MD; Jonathan A. Beilan MD; Rafael E. Carrion MD; Ricardo M. Munarriz MD

FIRST PUBLISHED: July 2019 – The Journal of Sexual Medicine 

DOI: https://doi.org/10.1016/j.jsxm.2019.05.003

Introduction

Since inflatable penile prostheses (IPPs) were developed, “significant advances in infection prevention have been made.” However, infections still affect about 1% to 3% of men getting their first penile implant and up to 10% of men undergoing revision surgery.

In a past study, researchers were surprised to discover a fungal infection rate of 11.1%, as the common belief was that fungi “are unlikely to be severe enough to cause clinically significant infection.” This belief is not supported by medical studies, however.

The current study investigated IPP fungal infections and common patient and surgical factors that might contribute to them.

Materials and Methods

The study focused on retrospective data from 217 patients who were treated in 26 institutions. All of the men had had 3-piece IPPs that were either salvaged or explanted between 2001 and 2018. All of the IPPs had infection-retardant coatings (IRCs).

Infected implant spaces (and in some cases explanted devices) were cultured.

Further information, including diabetes status and body mass index (BMI) was requested from 26 patients with fungal infections.

Results 

The following results apply to the 26 men (12% of all) with fungal infections:

• The average age at the time of implantation was 63 years.
• Fifteen (57.8%) had undergone primary implantation; the rest had had an average of 1.7 surgeries related to their IPP.
• Eighty-eight percent of the men were diabetic or overweight, with diabetes found in 69% of the patients, with a mean HbA1c of 8.4% (5.8-13.3).
• The mean BMI for all patients was 30.1 kg/m2. For those with diabetes, average BMI was 30.8 kg/m2; for nondiabetic patients, it was 28.8 kg/m2.
• Eighty-five percent of the men were overweight or obese, and 27% were morbidly obese.
• Antibiotic information was available for 22 patients. Ninety-five percent received IV antibiotics in accordance with American Urological Association guidelines.
• Sixty-five percent of the infected devices had fungal infections alone. In the others, both fungi and bacteria were found.

Discussion 

In this study, most of the men with fungal IPP infections were diabetic and overweight. Further research on both diabetes and obesity in prosthetic urology is needed.

Certain infectious organisms appear to be more common since the development of IRCs. Such organisms are “different from established norms,” and it is possible that certain populations of IPP patients may be at higher risk for infections with them. With this in mind, some authors suggest the introduction of antifungal agents in salvage procedures and the adjustment of doses of antifungal agents and antibiotics used in those higher risk IPP patients.

“We believe that it is clear that infectious organisms are changing, and it is logical to posit that certain populations may be prone to IPP infection with particular organisms.”

Several limitations were acknowledged, including the following:

• The number of men with fungal IPP infections was small, although fungal IPP infections are generally rare.
• The study was descriptive, with no control group.

Conclusions

Most men with fungal IPP infections in this study were either diabetic or overweight. “Further investigation is needed to evaluate whether antifungal prophylaxis may be appropriate in these patient populations.”