Gregory W. Hendey
Originally described in 1764 by Baurienne, perineal gangrene today bears the name of Jean-Alfred Fournier, a French dermatologist, who described a case in 1883 (1,2). Fournier gangrene is the most severe end of a spectrum of scrotal and perineal infections, ranging from cellulitis to abscesses to necrotizing gangrene. Primary abscesses of the scrotal skin may originate from infections of the hair follicles or sweat glands. These abscesses tend to be superficial and similar to those found elsewhere on the body. Deep scrotal and perineal infections usually arise, on the other hand, from infection of the urinary tract or scrotal skin or from perirectal disease. Urogenital sources include extravasation of infected urine caused by a urethral stricture or after urethral instrumentation. Superficial skin abscesses, if left untreated or inadequately treated, may spread along deep fascial planes. Anorectal sources tend to be deep-rooted abscesses that may have spread extensively by the time of diagnosis. Eventually, the tunica albuginea is penetrated, with spread to Buck fascia. Once Buck fascia is invaded, the next barrier is the Colles fascia. Infection may spread anteriorly along the Colles fascia to involve the scrotum.
Fournier gangrene is a type of necrotizing fasciitis characterized by the rapid spread of a severe subcutaneous infection, with massive scrotal and perineal induration and swelling, which progresses to scrotal wall necrosis within 24 hours if not recognized and treated. The morbidity and mortality of Fournier gangrene are high. Though early reports estimated the mortality to be as high as 80%, more recent reports are less than 40% (1,3). The usual age of affected patients is 50 to 60 years, and diabetics and alcoholics are particularly at risk (1,4–7). The typical organisms include Escherichia coli, Bacteroides fragilis, Clostridium sp, and hemolytic streptococci, though community-acquired methicillin-resistant Staphylococcus aureus (MRSA) has been reported (4,8,9).
CLINICAL PRESENTATION
Deep scrotal abscesses and Fournier gangrene may present as generalized scrotal swelling. The onset may occur several days after instrumentation of a urethral stricture or in an inadequately treated diabetic with an initial superficial skin abscess. The patient may have a history of perirectal disease. Pain is usually intense, but initial physical examination of the affected area can be subtle. Eventually, fever and other constitutional symptoms emerge and may lead to hypotension and sepsis. Diabetic patients may present with ketoacidosis. The scrotum is usually edematous, indurated, erythematous, tense, and warm, with or without a localized area of fluctuance or necrosis.
DIFFERENTIAL DIAGNOSIS
Superficial scrotal skin abscesses seldom cause difficulty in diagnosis. A localized area of erythema with a smaller area of suppuration is found on examination. Most patients are afebrile and without constitutional symptoms. Superficial abscesses may be incised and drained under local anesthesia in the emergency department (ED).
Scrotal edema from congestive heart failure or lymphatic obstruction may appear similar to scrotal infection. Concomitant edema of the lower extremities, however, shifts the differential away from an infectious cause. Occasionally, edema of the scrotum occurs as a result of an allergic reaction, but the scrotum should not be tender to palpation, and the erythema and warmth are substantially less than those found in infectious causes. Cellulitis of the scrotum may present with significant edema, and the distinction from a deep abscess may be difficult. Severe cases of epididymoorchitis may also present with scrotal induration that mimics a deep scrotal abscess or Fournier gangrene. Other skin conditions that may mimic Fournier gangrene include pyoderma gangrenosum and warfarin necrosis.
ED EVALUATION
Rapid diagnosis and treatment of bacteremia are the principles of the initial approach. When the diagnosis is clinically obvious, immediate treatment and consultation is warranted. In less apparent cases, bedside ultrasonography may be helpful in differentiating hernia, cellulitis, localized abscess, and gas collections in the scrotal wall to facilitate a more rapid diagnosis (10). Subcutaneous air may also be demonstrated on plain radiographs of the pelvis, on ultrasound, or on computed tomography (CT) scan, although this finding is not necessary to establish the diagnosis, which is largely clinical. If urethral obstruction is suspected as the inciting cause, a urethral catheter should be placed into the bladder. The rectum and perineum should be examined carefully for induration and fluctuance. Blood cultures and laboratory studies should be obtained in anticipation of surgery and postoperative critical care.
KEY TESTING
• CBC, electrolytes, lactate, blood cultures, type and screen
• Imaging as needed (plain films, ultrasound, CT scan) to make the diagnosis or define extent of disease
ED MANAGEMENT
Fournier gangrene requires aggressive medical resuscitation with intravenous (IV) fluids and broad-spectrum antibiotics, such as ampicillin/sulbactam (Unasyn) 3 g IV, ticarcillin/clavulanate (Timentin) 3.1 g IV, or piperacillin/tazobactam (Zosyn) 3.375 g IV, and Clindamycin 900 mg IV. Vancomycin 1 g IV should be added if MRSA is suspected.
These modalities should be instituted as soon as possible, while urologic consultation is obtained, and the operating room should be alerted for emergency surgical debridement. Although aggressive resuscitation, supportive measures, and early antibiotics are important aspects of the initial emergency care for patients with Fournier gangrene, this is a surgical emergency, and the definitive care is operative. It is imperative to involve the surgeon early, without delaying for the results of laboratory or imaging studies. Surgical debridement tends to be extensive and often requires multiple procedures, including urinary and fecal diversions and skin grafting.
CRITICAL INTERVENTIONS
• Initiate fluid resuscitation and broad-spectrum antibiotic coverage as soon as the disease is recognized.
• Immediately consult a surgeon, as aggressive debridement is necessary in most cases. If appropriate care is unavailable, consider a rapid transfer to a facility with such services.
DISPOSITION
Surgical drainage with wide debridement and antibiotic therapy must be instituted rapidly because of the extremely aggressive nature of Fournier gangrene (7). Postoperative hyperbaric oxygen therapy has also been recommended and may promote wound healing (1,5,6,11).
All patients with scrotal cellulitis, deep abscess, or Fournier gangrene should be admitted to the hospital, and most will require surgery and critical care resources.
Patients should be transferred if surgical consultation or intensive care beds are not available.
Common Pitfalls
• Underestimating the severity of infection. With Fournier gangrene, a delay of several hours can make a significant difference in morbidity (1,4,7).
• Failure to rapidly institute fluid resuscitation, antibiotics, and surgical consultation.
REFERENCES
1. Thwaini A, Khan A, Malik A, et al. Fournier’s gangrene and its emergency management. Postgrad Med J. 2006;82(970):516–519.
2. Who Named It? http://www.whonamedit.com/synd.cfm/2521.html. Accessed March 7, 2013).
3. Aridogan I, Izol V, Abat D, et al. Epidemiological characteristics of Fournier’s gangrene: A Report of 71 patients. Urol Int. 2012;89(4):457–461.
4. Atakan I, Kaplan M, Kaya E, et al. A life-threatening infection: Fournier’s gangrene. Int Urol Nephrol. 2002;34:387–392.
5. Eke N. Fournier’s gangrene: A review of 1726 cases. Br J Surg. 2000;87:718–728.
6. Gurdal M, Yucebas E, Tekin A, et al. Predisposing factors and treatment outcome in Fournier’s gangrene. Analysis of 28 cases. Urol Int. 2003;70:286–290.
7. Korkut M, Icoz G, Dayongac M, et al. Outcome analysis in patients with Fournier’s gangrene: Report of 45 cases. Dis Colon Rectum. 2003;46:649–652.
8. Kalorin CM, Tobin EH. Community associated methicillin resistant Staphylococcus aureus causing Fournier’s gangrene and genital infections. J Urol. 2007;177(3):967–971.
9. Bjurlin M, O’Grady T, Kim D, et al. Causative pathogens, antibiotic sensitivity, resistance patterns, and severity in a contemporary series of Fournier’s Gangrene. Urology. 2013;81(4):752–758.
10. Kim D, Kendall J. Fournier’s gangrene and its characteristic ultrasound findings. J Emerg Med. 2013;44(1):e99–e101.
11. Gallego V, Garcia F, Povo Martin I, et al. Hyperbaric oxygen treatment in urology. Arch Esp Urol. 2011;64(6):507–516.