Successful Conservative Therapy for Infected Penile Implants: A Case Series

Background

The penile implant (PI) is the last step on the ladder to the management of erectile dysfunction (ED). It has been widely used in patients who fail to respond to conservative therapy. Post-priapism ED is especially an indication mimicking erec-tile function. Semirigid and inflatable devices are the 2 types of a penile prosthesis [1], and the choice depends on patient preference, surgeon experience, and previous surgical history. Penile prosthesis infection is one of most feared and devastating complications for urologists. Historically, penile pros-thesis infection has been managed with removal of the device and a course of antibiotics. However, some papers reported successful conservative management of selected patients with penile prosthesis infection. We report a series of 4 cases of malleable and inflatable penile prosthesis infections (Tactra™ Malleable Penile Prosthesis – Boston Scientific) and (Coloplast Titan prosthesis®) who were managed conservatively and an outcome of resolution of infection.

Case Reports

CASE PRESENTATION 1:

A 41-year-old man had a past medical history of sickle cell anemia, chronic kidney disease, and rheumatic heart disease. He was referred to a tertiary center as a case of ED 1 month after an episode of priapism that lasted 3 days. The patient had insertion of, as he preferred, malleable penile prosthesis (Tactra™ Malleable Penile Prosthesis – Boston Scientific) with a penoscrotal approach and right cavernous mesh placement (Polyglycolic acid®) after excision of fibrotic tissue (Figure 1A). He tolerated the procedure well and was discharged with amoxicillin/clavulanic acid and ciprofloxacin for 2 weeks.

One month after the surgery, he developed a low-grade fever at home, which was associated with purulent wound discharge. He sought medical attention at a local hospital and was prescribed antibiotics for 1 week, but the symptoms did not improve. The patient presented to our emergency department 3 weeks after his symptoms first started. On examination, the patient was vitally stable and afebrile. There was a small, left lateral distal shaft opening with pus discharge (Figure 1B), but no shaft swelling or tenderness. Laboratory workup showed white cell count (WBC) count of 12×109/µL, a C-reactive protein (CRP) level of 1.4 mg/L, and urine culture was negative. The infectious diseases team was involved, and the patient was started empirically on intravenous (IV) antibiotics while waiting for the wound culture result, and was started on piper-acillin/tazobactam 3.375 g IV every 6 h for 6 days, then the dose was adjusted to 2.25 g for 7 days (13 days total Tazocin administration), and vancomycin 750 mg IV daily for 3 days, then the dose was adjusted to 500 mg for 9 days (12 days total vancomycin administration).

Penile and pelvic magnetic resonance imaging (MRI) showed 14×7 mm of loculated fluid collection in the left corpora cavernosum (Figure 2) The initial wound culture showed light normal skin flora. Thereafter, an antifungal was added (fluconazole 100 mg orally daily), together with the IV antibiotics. The wound discharge and leukocytosis showed improvement. The patient completed 2 weeks of IV antibiotics and 6 days of fluconazole and was discharged on amoxicillin/clavulanic acid, ciprofloxacin, and fluconazole for 14 days. Follow-up after 5, 16, and 23 weeks in the outpatient department showed complete wound healing without associated fever, wound discharge, or swelling (Figure 3).

CASE PRESENTATION 2:

This 62-year-old patient had diabetes mellitus (DM) and hypertension. He had insertion of an inflatable penile prosthesis (Coloplast Titan prosthesis®) with penoscrotal approach. He was discharged with amoxicillin/clavulanic acid and ciprofloxacin for 2 weeks. He presented to the outpatient department 41 days postoperatively with a 2-cm penoscrotal wound dehiscence associated with purulent discharge (Figure 4A). Vital signs were normal, without fever. The laboratory workup was unremarkable. A wound culture showed growth of Klebsiella pneumonia. The patient was admitted and IV antibiotics were started, with vancomycin 750 mg IV every 12 h and gentamycin 100 mg IV every 8 h. MRI showed 3×4×2 cm fluid collection around the scrotal pump (Figure 5). The MRI also showed distal corporal crossover of the left cylinder to the right side. The patient completed 5 days of IV antibiotic with dressing changes every 8 h with wet-to-dry half-strength povidone. However, the patient self-discharged against medical advice as he was bored and had a family issue. He was given amoxicillin/clavulanic acid and ciprofloxacin for 2 weeks more. Follow-up after 1 month showed complete wound healing without associated signs of inflammation (Figure 4B).

CASE PRESENTATION 3:

This 61-year-old patient was known to have DM and ischemic heart disease. He had an insertion of an inflatable penile pros-thesis (Coloplast Titan prosthesis®) with penoscrotal approach. He was discharged with amoxicillin/clavulanic acid and ciprofloxacin for 2 weeks. At 30 days postoperatively, he had low-grade fever, pain, purulent discharge, and a small 1-cm opening at the penoscrotal junction (Figure 6A). He was vitally stable without associated fever. Laboratory workup including urinalysis was unremarkable. The patient was admitted and was administered IV vancomycin 1g IV every 8 h, and gentamicin 80 mg IV every 12 h. He received surgical site dressing changes every 8 h with wet-to-dry half-strength povidone. A wound culture was negative. He was discharged after he completed 10 days of IV antibiotics. Follow-up at 1 and 3 weeks showed complete wound healing (Figure 6B).

CASE PRESENTATION 4:

A 61-year-old patient was known to have DM and IHD. He had insertion of inflatable penile prosthesis (Coloplast Titan pros-thesis®) with penoscrotal approach and was discharged with amoxicillin/clavulanic acid and ciprofloxacin for 2 weeks. One month postoperatively, he presented to the emergency department with history of low-grade fever and pain at the surgical site that was associated with purulent discharge (Figure 7A). His vital signs were normal. A 2-cm opening at the surgical site had active pus discharge. Laboratory workup including urinalysis was unremarkable. A swab of the discharge was negative. The patient completed 10 days of intravenously antibiotics with vancomycin 1 g IV every 8 h, and gentamicin 80 mg IV every 12 h, along with dressing changes 3 time a day with wet-to-dry half-strength povidone and was discharged home thereafter. One week after hospital discharge, he came to the clinic with marked improvement of the wound without associated discharge (Figure 7B).

Discussion

Erectile dysfunction (ED) is the inability to have a sufficient erection and/or to maintain erection long enough for satisfactory sexual performance. Erectile dysfunction is quite common, affecting about 12 million U.S. men [2]. Multiple risk factors can cause erectile dysfunction, such as, neurological, hormonal, and vascular factors. However, aging is considered a major risk factor [3]. Similar to any intervention, especially prosthesis, implants carry the risk of postoperative infections, which is considered to be the most bothersome complication due its long-term outcome. Furthermore, infection can require further surgery, loss of penile tissue, or failure to replace the pe-nile prosthesis [4].

Implantation of a penile prosthesis is the definitive and last step approach for patients who develop ED, regardless of the etiology. There are certain risk factors for the development of ED. For example, priapism accounts for 7% of ED in patients who had a penile prosthesis. As with any intervention, especially prostheses, implants carry the risk of postoperative infections [5]. Penile prosthesis infection is one of the most devastating complications for urologists because of its associated morbidity and difficulty for surgeons. Approximately 8% of all patients who have penile prosthesis surgeries develop an infection, of which the malleable device accounts for 5% of cases [5]. Infection rates vary from 0.6% to 8.9% for primary procedures, but are reported to be 1–3% in clinical practice [6,7]. Jarow noted an incidence of 13.3% associated with implant repairs and an even higher incidence of 21.7% when penile reconstruction accompanied the repair [8]. Morbidity can be reduced by identifying the infectious agent and recognizing early local and systemic indications that might indicate severity. It is important to identify and try to prevent any risk factors to reduce the risk of infection in penile prostheses. The importance of taking the proper precautions and being knowledgeable about how to handle any complications related to penile implants cannot be overstated.

Habous and colleagues reported a high success rate (84%) of conservative management of infected prostheses with antibiotics, with an average time for resolution of infection of 49 days. Furthermore, all patients with positive wound culture of Pseudomonas failed conservative management and were eventually required to remove the device, which could predict the failure of non-surgical management [9]. The high success rate could be attributed to careful selection criteria for patients who were selected for conservative management. It is also evident that prosthesis infection in orthopedic surgery patients with Pseudomonas carries the worst outcome compared to other organisms [10].

Henry et al concluded that conservative management in patients with localized penile prosthesis infection is an option, even in the presence of purulent discharge. Classically, the presence of purulent discharge is managed with removal of the device. The time to complete resolution of prosthesis infection in the 15 patients was estimated at 76 days [11]. The conservative approach is cost-effective and is estimated to cost 15% of the reimplanting malleable device [9]. However, it should not affect the surgeon’s decision to either explant or observe, and patients should be monitored for any signs of clinical deterioration.

Penile prosthesis infections can have high rates of morbidity, leading to re-operative procedures, losing the erectile function provided by PI, shorter penile length, and emotional trauma [12]. More aggressive infections with systemic effects are usually caused by E. coli, S. aureus, Klebsiella, Serratia, or Pseudomonas species [13]. Although the infection rate of PIs is decreasing, the infections that do take place are usually caused by more aggressive organisms and are systemic in nature. The infections are not usually salvageable due their virulence and ability to resist antimicrobial treatments. Antibiotic resistance, a worldwide challenge, can naturally present as a challenge to the conservative management of penile prosthesis infection.

The potential biofilm that could form due to device contamination pre-operatively and intra-operatively has been proven to usually contain bacteria strains that have antibiotic-resistance genes [14,15]. This urges the need for efficient and effective methods beyond those available to prevent and treat biofilm formation and, in turn, mitigate antibiotic resistance in penile prosthesis infections. Prevention strategies for avoiding PI infection have been well researched and are abundant in the literature. Surgical factors can include antibiotics used in any stage of the surgery, pre-surgical scrubbing, surgeon experience (although showing relatively weaker evidence), surgical technique, and hair removal. Antimicrobial selection for the pre-operative stage can include aminoglycoside combined with a first- or second-generation cephalosporin or vancomycin [16]. In addition, most surgeons apply some sort of antibiotics peri-operatively [17]. Despite recent studies proving no decrease in postoperative infections with postoperative antibiotics for inflatable penile prosthesis, most clinicians, including us, discharge the patient on some sort of antibiotics for at least 24 h [18]. In terms of pre-surgical scrubbing, the current evidence shows no difference between a classic 10-min and the newer 90-s scrub sticks or alcohol-based solutions methods. However, these recommendations are not specifically based on implant infection rates and are general [19]. The no-touch technique has helped reduce infection rates from 5.3% to 0.46%. This is superior to using implants with coatings, which drops infection rates to 1.9% [20]. Although most surgeons remove the hair around the scrotum and the suprapubic area, it has been shown to provide no evidence of decrease in PI infection [21]. Regarding patient-related factors, diabetes has been shown to have a pivotal role in PI infections. Diabetic patients are more susceptible to infections because of impaired defense mechanisms, such as impaired leukocyte function and an impaired mobilization to the site of infection induced by angiopathy. In a systematic review of 9041 diabetic patients and 36 517 non-diabetics, diabetes has been shown to increase the infection risk and glycosylated hemoglobin (Hb1Ac) being a reliable indicator in predicting infections [22].

American Urological Association guidelines for the use of prophylactic antibiotics for a number of urologic procedures were published in 2008 [23]. These guidelines included a brief section on the use of antibiotics during prosthesis installation. They were based on studies in general surgery on mesh inguinal herniorrhaphy and orthopedic literature for artificial joint placement because there was a lack of substantial series on their usage in urologic prosthetic surgery. Systemic vancomycin and gentamicin should be started 1 h before making the incision and continued for up to 24 h after surgery, but not longer. If considered necessary, a third-generation cephalosporin could replace vancomycin. A survey of urologists who commonly implant prosthetic devices found that a large majority also prescribed oral antibiotics for 5–14 days after surgery, typically in the form of sulfamethoxazole-trimethoprim (eg, Bactrim®, Septra®, Cotrim®) [24]. First- or second-generation cephalosporins or vancomycin should be used in addition to an aminoglycoside for 24 h prior to surgery, according to AUA recommendations issued since 2008 and then revised in 2012 [25]. However, the latest edition of the AUA guidelines on erectile dysfunction discourages against implantation in the presence of a positive urine culture [26]. In comparison, the EAU does not provide any specific regimens due to significant variations in antibiotic sensitivity and resistance trends across Europe and internationally, and has encouraged adherence to local microbiological guidelines [27].

Conclusions

Choosing patients with an infected penile prosthesis for conservative management should be tailored carefully to selected patients. Any patient who develops signs of systemic sepsis should be immediately managed classically with the removal of the infected prosthesis. However, the conservative approach is still an option with intravenously piperacillin/tazobactam, vancomycin, and antifungal to cover a broad spectrum of microorganisms.