Corpus cavernosum abscess complicating distal shunt procedures for priapism

Abstract

Abscess of the corpus cavernosum is a rare condition. We describe the case of a 36-year-old male presenting with bilateral corpus cavernousm abscesses, on a background of distal shunt procedures for recurrent priapism, that was managed with a bilateral corporotomy and systemic antibiotic therapy.

Level of Evidence: Level 4

Case history

A 36-year-old male presented to the emergency department with a four-day history of drug-induced priapism. His medical history included depression and asthma. The patient had no history of diabetes or steroid use. His regular medications consisted of fluoxetine and quetiapine. The patient reported a long-standing history of erectile dysfunction prior to the onset of his recurrent priapism and had taken sildenafil multiple times in the past.

After a failed attempt at cavernosal aspiration with phenylephrine, a Winter’s shunt was performed under penile block. This was successful. However, the patient presented again four days later with recurrent priapism. Cavernosal aspiration failed, and a repeat Winter’s shunt was performed the following day. Intravenous ceftriaxone was administered for each procedure.

The patient absconded from hospital two days later. However, he presented again to the emergency department 14 days after the second Winter shunt. He described a two-week history of penile pain and swelling, with fever developing over the 12 hours prior to presentation. He had been taking pseudoephedrine as instructed at home for his recurrent priapism prior to his third presentation.

On admission, he was tachycardic (heart rate 125 bpm) and had a fever of 38.6°C. Examination revealed a swollen erect penis with erythematous skin. There was an extensive deep mass, which was fluctuant, extending bilaterally to the base of the penis. Testicular and scrotal examinations were normal.

Investigations showed raised inflammatory markers, with a white cell count on presentation of 24.1×10⁹/L and C-reactive protein of 357 mg/L. A bedside ultrasound showed a potential collection within the corpus cavernosum bilaterally. The patient underwent needle aspiration in the emergency department, with a total of 30 mL pus collected for microscopy, culture and sensitivities. He was commenced on intravenous fluids and broad-spectrum antibiotics (ceftriaxone, azithromycin and flucloxacillin in the emergency department and then switched to piperacillin-tazobactam on admission under urology).

Computed tomography revealed a marked fluid distension of the corpora cavernosa bilaterally, with enhancement of the surrounding tunica albuginea. This was associated with a bilobed fluid collection extending across the ventral aspect of the mid-penile shaft suggestive of a bilateral corpus cavernosum abscess (Figure 1).

Figure 1.

Computed tomography images of corpus cavernosum abscess.

The patient was emergently taken to theatre for a bilateral corporotomy and drainage of the abscess. A longitudinal incision was made near the base of the penis. Artery forceps were inserted to the opposite side, and a separate incision was made over the forceps. Pus was drained, and the corpora were washed out with normal saline. A Penrose drain was inserted and secured using a silk suture and a combine dressing and crepe bandage applied (Figure 2).

Figure 2.

Intraoperative image.

The aspirated pus had Gram-negative bacilli on microscopy and grew a heavy growth of mixed anaerobes on culture. Prevotella bivia was isolated on blood cultures. The patient’s condition improved postoperatively. His tachycardia and fever settled, and his white cell count normalised. He continued on piperacillin-tazobactam for a further four days and BD saline flushes of the Penrose drain until it was removed on postoperative day 4. The patient self-discharged on a four-week course of oral amoxicillin-clavulanic acid and metronidazole. The patient failed to attend any further follow-up.

Discussion

Abscess of the corpus cavernosum is a rare condition. A review of the literature revealed 43 known case reports since 1980 (Appendix 1). They usually present with progressive penile pain and swelling. ¹

Cases have been described after trauma, as a complication of cavernosography, as an unusual presentation of gonorrhoea or tuberculosis, following intracorporeal injections, priapism, from local infections or from haematogenous seeding from distant infections, following penile prosthesis placement, as a complication of Winters’ procedure or from indeterminate causes.^1–6 Iida et al. proposed corpus cavernosal abscess as an early symptom of penile pyodermal gangrenosum. ⁷ More than a third of corpus cavernosal abscesses have also been reported as idiopathic. Almost half of the cases reported bilateral corpus cavernosum abscesses, as seen with our patient.

The corpora cavernosa are thought to be resistant to haematogeneous dissemination of infection, the aetiology of which is unclear. ⁸ However, previous case reports have attributed abscess of the corpus cavernosum to bacteraemia from dental infections. ⁵ Priapism leads to ischaemia in the corporeal tissue and can make it more prone to infection. ⁴ As with Paladino et al., pathogens were likely introduced during the multiple procedures performed for priapism.

A number of different pathogens have been the causative organism, perhaps due to the variety of potential aetiologies of corpus cavernosal abscess. Most cases involved Gram-positive cocci. However, a number of cases were caused by Gram-negative bacilli. Staphylococcus aureus, Streptococci, Fusobacteria and Bacteroides are common organisms amongst reported cases. ¹ Corpus cavernosum abscesses can also occur from fungal infections ⁹ as well as Mycobacterium tuberculosis. ⁶ Three cases of recurrent corpus cavernosum grew MRSA on cultures.^1,7,10 P. bivia is an anaerobic Gram-negative bacillus species which resides in the flora of the female genital tract and is occasionally found in the oral flora. ¹¹ It is typically associated with infections of the female urogenital tract and the oral cavity. ¹² P. bivia infections have also been found in rare locations such as the bones/joints, nail bed, male external genitalia, endocardium and the chest wall. ¹¹ As the patient admitted to ongoing sexual activity with his recurrent priapism, it is possible that Prevotella became the causative organism as a result of attempted sexual intercourse following the recurrent drainage procedures.

Anaerobic organisms are frequently cultured in suppurative genitourinary tract infections. ¹³ In our case, ceftriaxone was given prophylactically during the patient’s procedures, which did not provide any anaerobic cover. Greater antibiotic coverage may be required in recurrent priapism with multiple drainages to cover for possible anaerobic infection.

Early surgical intervention with intravenous antibiotics is recommended to prevent serious complications such as necrotising fasciitis and persistent infection requiring a penectomy. Possible complications of surgical drainage can include abscess recurrence, fistulae, poor erectile function and secondary fibrosis leading to penile deviation. ⁸ Intravenous antibiotics and radiologically guided aspiration could be considered a viable alternative of treating a corpus cavernosum abscess while also reducing the risk of secondary fibrosis associated with corporotomy, with some cases showing successful resolution of the abscess without any complications.^14,15 However, given the risk of recurrence with incomplete evacuation of the abscess, surgical drainage remains the mainstay of therapy. ¹ Previous case reports have necessitated a penectomy for persistent infections. ¹⁰ Previous case reports showed pyoderma gangrenosum as the underlying cause of persistent abscess of corpus cavernosum despite surgical drainage. Initiation of steroid treatment avoided the need for a penectomy. ⁷

Conclusion

This is only the second case of corpus cavernosal abscess as a result of recurrent priapism and following a Winter’s procedure. Adequate antibiotic coverage, including anaerobic cover, is required with recurrent priapism, requiring multiple drainages to prevent the development of a corpus cavernosal abscess. Early administration of intravenous antibiotics and surgical intervention or radiologically guided aspiration are crucial to avoiding serious complications associated with corpus cavernosal abscess.