Fournier Gangrene: An Unusual Presentation Involving the Bulbous Urethra and Forming Free Gas in the Urinary Bladder

A 47-year-old man presented to the Emergency Department (ED) with progressive scrotal swelling and urine leakage through the scrotal wall for 3 days. He had general malaise, fatigue, and subjective fevers during that time. He reported having a weak urinary stream and urgency for the last 2 years. His voiding symptoms had gradually worsened over the course of a few weeks. Moreover, 3 days before the admission, he could not void by himself through the urethra but had urine leakage through the scrotal wall and bilateral scrotal swelling. He denied any history of trauma to the genitourinary tract. There was no history of diabetes mellitus or other medical comorbidities, but heavy alcohol use was strongly suspected. He was generally in poor hygiene and in a drunken state when he was taken to the ED.

On physical examination, there was scrotal swelling that was approximately 15 × 15 cm in size, and a gangrenous skin discoloration was noted. The scrotal wall was edematous and exquisitely tender. The penis was tender and mildly swollen. The erythema extended toward the anterior abdominal wall up to 2 cm below the umbilicus level. No perianal lesions were found. He had a body temperature of 38.3°C, a blood pressure of 130/80 mm Hg, a heart rate of 118 beats/min, and respiratory rate of 26 breaths/min.

Laboratory values revealed a leukocytosis with a left shift (white blood cell count of 20,890/mm³) and an increased C-reactive protein concentration (13.03 mg/dL). An abdominopelvic computed tomography scan with contrast showed significant subcutaneous soft tissue edema and emphysematous changes in the scrotum, extending into the perineum and lower abdominal wall. There were multiple gas pockets around the corpus spongiosum and a markedly thickened bladder wall, with free gas in the bladder (Figure 1).

The patient was taken urgently for aggressive surgical debridement of the scrotum and lower abdomen. During surgery, there was extensive necrosis involving the skin and fascia of the scrotum, perineum, and extension to the lower portion of the abdomen, whereas the testes were spared (Figure 2A ). All obviously necrotic tissues were debrided. A 10-mm-sized midline defect of the urethra was noted on the ventral side of the bulbous urethra (Figure 2B). Because the viability of the bulbous urethra was questionable, a urinary diversion with suprapubic cystostomy was done. Empirical broad-spectrum antibiotics including clindamycin were administered. He underwent repeated debridement to ensure that all infected and necrotic tissue was removed. Enterococcus and Enterobacter species were cultured from the necrotic debris. On postoperative day 20, the patient went back to the operating room and the testes were moved into a subcutaneous pocket in the upper thigh before skin grafting. The patient underwent a split-thickness skin graft for the scrotal defect on postoperative day 35. The patient was discharged uneventfully, and delayed urethral reconstruction with end-to-end anastomosis was performed 6 months later. There has been no evidence of recurrence of the fistula or urethral stricture formation during the 1-year follow-up postoperatively.

Fournier gangrene (FG) is a specific form of infective necrotizing fasciitis, and the infective process leads to thrombosis of subcutaneous blood vessels. This infectious process predominantly involves the superficial and deep fascial planes of the genitalia (). It may be a life-threatening disorder if emergent surgical intervention is delayed (). Although the original description of FG was emphatic about the absence of a known cause, it was well known that anorectal infections, genitourinary infections or trauma, or cutaneous infections of the perineum may be implicated in the disease (, ).

Comorbidities that compromise the host immune system are necessary predisposing factors for the development of FG. The most common associations are diabetes, which is present in 40–60%, and chronic alcoholism, which affects 25–50% (, ). Chronic abuse of alcohol is the only predisposing identifiable factor in our case.

Genitourinary infection associated with trauma or stricture is known to be the most common urologic etiology for FG. As seen in the development of urethral diverticulum, the periurethral glands seem to be the probable site of origin of infection (). Recurrent infection of the periurethral glands in pre-existing urethral pathology might result in the formation of periurethral abscess, and subsequent rupture of these infected glands or abscess into the urethral lumen may occur. It is thought that the gas-producing microorganisms in the site of urethral lesion cause fermentation of the urinary glucose or albumin. This, in turn, leads to the release of carbon dioxide bubbles, which collect in the corpus spongiosum or lumen of the urethra. It might be difficult for gases at the initial urethral lesion to escape outside, under the circumstance, with chronic urinary stasis due to urethral stricture. Therefore, the free gas in the bladder may be the result of ascending infection, which originated from distal urethral pathology (Figure 1). If an immunocompromised host does not receive appropriate management in this situation, the localized infection may spread to Buck’s fascia. Then, if Buck’s fascia is penetrated, the necrotizing process can extend beyond initial urethral lesion and spread along the dartos fascia into the scrotum and up the abdominal wall along the Scarpa fascia (). This proposed pathophysiologic process seems to explain the route and spread of necrotizing infection in our patient.

Urinary diversion is accomplished with a urethral catheter in most cases. However, a suprapubic catheter may be required if there is a urologic etiology of the infection with urethral stricture or urinary extravasation (). In our case, urethral catheterization was impossible due to bulbous urethral necrosis associated with possibly preceding urethral stricture and periurethral abscess. Intraoperatively, the corpus spongiosum around the bulbous urethra was necrotic and partially digested. Therefore, we employed a temporary urinary diversion with suprapubic cystostomy.

In summary, urethral stricture with or without urinary extravasation should be strongly considered as the source of infection in patients with suspected FG who cannot void spontaneously. In that situation, because inappropriate urethral catheterization can aggravate urethral pathology, suprapubic urinary diversion is mandatory before definitive surgical treatment.