Inflatable penile prosthesis and salvage protocol for mechanical failure: is it really necessary?

INTRODUCTION: Penile prosthesis patients with mechanical failure who wish continued treatment require device removal and replacement. Infection rates as high as 18% have been reported for procedures involving replacement of malfunctioning penile prosthesis compared with 2% for primary implantation. AIM: The aim of this study is to compare the outcomes of patients who have had a penile prosthesis replacement for mechanical failure to determine if those who had a mini-salvage washout procedure had better outcomes than those who did not. METHODS: A retrospective chart review was performed of all patients undergoing inflatable penile prosthesis replacement for mechanical failure from 1997 to 2010. Demographics, past medical history, reason for device failure, type of device, time from original implantation to failure, operative details, culture results, and follow-up data were analyzed. MAIN OUTCOME MEASURES: Infection rates for penile implant revisions with and without mini-salvage washout. RESULTS: Forty-two patients underwent a mini-salvage procedure for mechanical failure and 87 patients underwent standard sterile replacement. There were no infections in the mini-salvage group and two (2.3%) in the standard sterile group (P=1.00). In patients with culture data available, two patients in each group had coagulase negative staphylococcus on culture, but none of these patients developed an infection. One patient who developed an infection had an intraoperative culture, which revealed no growth. The other patient with an infection did not undergo intraoperative culture testing. Operating room (OR) time was longer with the mini-salvage procedure (156 ± 36 minutes vs. 131 ± 31 minutes, P<0.001). CONCLUSIONS: Performing a mini-salvage procedure for patients undergoing penile prosthesis replacement for mechanical failure adds to operative time but did not significantly change the infection rate and may not be indicated. Furthermore, intraoperative culture results were not predictive of postoperative infection.

Multiple retained needles: an unusual complication of intracavernous self-injection.

Intracavernous self-injection of pharmacologic agents is an effective method of treatment of erectile dysfunction. Intracorporeal needle breakage is a rare complication of intracavernosal self-injection. We report an unusual case of multiple retained needles in a 44-year-old man who presented with penile edema after intracavernous self-injection complicated by needle breakage. The patient was treated with nonoperative therapy and observed on a course of antibiotics to which he responded favorably. He continued to have good erectile function. We also present a review of the reported data and recommend a treatment strategy for the management of retained intracorporeal needles.

Effects of C-peptide on expression of eNOS and iNOS in human cavernosal smooth muscle cells.

OBJECTIVES: To investigate the role of C-peptide alone or in conjunction with insulin on the expression of nitric oxide synthase (NOS) in human corpus cavernosum smooth muscle cells (HCSMCs). Erectile dysfunction, among diabetic patients, is a significant health problem. The specific causes of erectile dysfunction are unknown. It has been suggested that impairment of penile relaxation is related to a reduction of penile NOS. Plasma levels of C-peptide and insulin are decreased in individuals with type 1 diabetes and late-stage type 2 diabetes. METHODS: Primary cultures were initiated from explants of HCSMCs. Confluent cells at passages 2 to 4 were assigned to one of four groups with the following incubation conditions: (a) 27 mM glucose, (b) 27 mM glucose and insulin, (c) 27 mM glucose and human recombinant (hr)C-peptide, and (d) 27 mM glucose, insulin, and hrC-peptide. After 24 hours, total RNA and protein were extracted from cells and subjected to reverse transcriptase-polymerase chain reaction and Western blot analysis, respectively. Intracellular Ca(2+) was examined under the four conditions, using the Fura 2 method. RESULTS: The least expression of endothelial NOS (eNOS) and inducible NOS (iNOS) in HCSMCs was observed in cells exposed to 27 mM glucose alone. Increased expression of eNOS and iNOS was found after treatment with insulin or hrC-peptide alone, and the maximal expression of eNOS and iNOS was detected in HCSMCs exposed to both insulin and hrC-peptide. Western blot analyses using eNOS and iNOS antibodies confirmed the RNA data. These effects are likely mediated by the insulin-induced and/or C-peptide-induced increase in intracellular Ca(2+). CONCLUSIONS: Our results demonstrated that C-peptide, in the presence of insulin, increases the expression of iNOS and eNOS in HCSMCs. These results suggest that C-peptide, especially in conjunction with insulin, may have beneficial effects on cavernosal smooth muscle relaxation.

Antibiotic soaked hydrophilic coated bioflex: a new strategy in the prevention of penile prosthesis infection.

OBJECTIVES: To find conditions that reduce the susceptibility of penile prostheses to infection, we studied the effect of coating the surface of polyurethane (Bioflex) with a hydrophilic material with and without antibiotics in decreasing bacterial colony counts both in vitro and in experiments in rats. MATERIALS AND METHODS: The in vitro experiment was performed using seven strips each of polyvinylpyrrolidone (PVP)-coated and uncoated polyurethane. These strips were dipped in saline for 5 minutes followed by incubation in a suspension of Staphylococcus epidermidis (SE) for a period of 10 minutes. Colony counts were determined after sonication of strips. For the in vitro experiments, 60 rats were used. Thirty animals each had uncoated or coated polyurethane implanted subcutaneously. In each group, strips were implanted after dipping them in either saline (N = 15) or an antibiotic solution (N = 15) consisting of 1 g/L vancomycin and 160 mg/L gentamicin. A bacterial suspension containing SE was then directly introduced into the subcutaneous pockets of all the animals prior to closure. After 7 days, strips were explanted along with 0.5 x 0.5 cm of surrounding tissue, and sonicated. Colony counts were performed on each sonicate. The data were analysed using Student's t-test. A P-value less than or equal to 0.05 was considered to be statistically significant. RESULTS: The in vitro study demonstrated a statistically significant (41%) reduction in the colony count of SE within the coated polyurethane strips compared to the uncoated Bioflex strips (150 +/- 44.7 CFU vs. 253 +/- 45.0 CFU, respectively, P-value < 0.05). Animal studies showed that bacterial CFU was highest in the uncoated Bioflex strip (29 +/- 24.5 CFU), followed by uncoated Bioflex with antibiotic treatment (24 +/- 28.1 CFU), coated Bioflex (17 +/- 25.2 CFU) and coated Bioflex with antibiotic treatment (13 +/- 16.1 CFU). Antibiotic treatment of coated Bioflex caused a significant reduction in the bacterial CFU compared to uncoated Bioflex (13 +/- 16.1 vs. 29 +/- 24.5 CFU, respectively, P = 0.04). This represents a 55% reduction in the bacterial count. While the reduction in the bacterial count in the coated Bioflex strip was not statistically different from that in the uncoated strip, a trend towards significance was noted with a 41% reduction (P > 0.05) in bacterial count in the coated Bioflex group compared to uncoated Bioflex. CONCLUSIONS: In conclusion, in vitro studies demonstrate a significant (41%) reduction in the colony count of SE in PVP-coated polyurethane compared to uncoated polyurethane. In vivo study in rats showed that antibiotic treatment of PVP-coated Bioflex resulted in a statistically significant reduction (55%) in colony count of SE compared to uncoated Bioflex.

Comparison of satisfaction rates and erectile function in patients treated with sildenafil, intracavernous prostaglandin E1 and penile implant surgery for erectile dysfunction in urology practice.

PURPOSE: We compared erectile function status and satisfaction rates in patients who received treatment for erectile dysfunction (ED) with sildenafil, intracavernous prostaglandin E1 (ICI) and penile implant surgery (IPP). MATERIALS AND METHODS: A total of 138 consecutive patients who received treatment for ED between April 2000 and April 2001 were considered candidates for study. Mean followup was 19.54 months. Of the patients 27 were not available for followup and 26 were not on any form of treatment. Of the patients receiving treatment for ED 85 were administered the Erectile Dysfunction Inventory for Treatment Satisfaction (EDITS) questionnaire and the Erectile Function Domain (EFD) of the International Index of Erectile Function questionnaire. Three treatment groups were identified, including 31 patients on sildenafil citrate, 22 on ICI and 32 who underwent IPP. Mean total EDITS, EDITS Index and EFD scores in the 3 groups were considered for statistical evaluation. RESULTS: There was no statistical difference in the total EDITS (25.59 versus 27.06, p = 0.48), EDITS Index (58.16 versus 61.15, p = 0.49) or EFD (22.91 versus 20.26, p = 0.12) score between the groups on ICI and sildenafil citrate, respectively. Total EDITS, EDITS Index and EFD scores were significantly higher in patients who underwent IPP than those on sildenafil citrate (36.09 versus 27.06, p <0.001, 82.03 versus 61.51, p <0.001 and 27.88 versus 20.26, p <0.001, respectively). Total EDITS, EDITS Index and EFD scores were significantly higher in patients who underwent IPP than those on ICI (36.09 versus 25.59, 82.03 versus 58.16 and 27.88 versus 22.91, respectively, all p <0.001). CONCLUSIONS: At a mean followup of 19.54 months patients who underwent penile implant surgery had significantly better erectile function and treatment satisfaction than those receiving sildenafil citrate and intracavernous prostaglandin E1.

Deep venous thrombosis due to compression of external iliac vein by the penile prosthesis reservoir.

Penile implant surgery has a high rate of success and a very high patient satisfaction rate. Compression of the external iliac vein by the reservoir of the penile implant is an extremely rare occurrence. We describe a case of deep vein thrombosis due to compression of the external iliac vein, which required replacement of the penile implant reservoir.