Editing Fournier's Gangrene

== Definition ==
'''<span style="color:#ff0000">An acute, rapidly progressive and potentially fatal, infective necrotizing fasciitis affecting the external genitalia, perineal or perianal regions</span>'''

== History ==

* First described in 1764 by Baurienne
* Named after Professor Jean-Alfred Fournier (1832-1914), a Parisian venereologist, who presented in 1883 a case of perineal gangrene in an otherwise healthy young man

== Relevant anatomy ==

* See Figure
* '''<span style="color:#ff0000">Superior to inguinal ligament</span>'''
** '''Layers (superficial to deep)'''
*** '''Skin'''
*** '''Camper’s fascia'''
**** Layer of fat-containing tissue of varying thickness and the superficial vessels to the skin that run through it.
*** '''<span style="color:#ff0000">Scarpa’s fascia</span>'''
**** '''<span style="color:#ff0000">Continuous with</span>'''
***** '''<span style="color:#ff0000">Colles’ fascia (superficial perineal fascia) in the perineum</span>'''
***** '''<span style="color:#ff0000">Dartos fascia in the penis</span>'''
***** '''<span style="color:#ff0000">Dartos fascia in the scrotum</span>'''
* '''Pelvis'''
** '''Colle’s fascia''' (see [[wikipedia:Fascia_of_Colles#/media/File:Gray403.png|Figure]])
*** Attached to the pubic arch and the base of the perineal membrane
**** Perineal membrane is also known as the inferior fascia of the urogenital diaphragm and, together with Colles’ fascia, defines the superficial perineal space
***** Superficial perineal space contains the membranous urethra, bulbar urethra, and bulbourethral glands. In addition, this space is adjacent to the anterior anal wall and ischiorectal fossae.
****** Infectious disease of the male urethra, bulbourethral glands, perineal structures, or rectum can drain into the superficial perineal space and can extend into the scrotum or into the anterior abdominal wall up to the level of the clavicles.
* '''<span style="color:#ff0000">Fournier's gangrene involves superficial and deep fascia (Camper's, Scarpa's/Dartos/Colle's) and skin</span>'''
** '''Often spares the deep muscular structures and, to variable degrees, the overlying skin.'''
*** '''<span style="color:#ff0000">Corpora, urethera, testes, and cord structures are usually not involved</span>'''
**** The contents of the scrotum, namely the testes, epididymides and cord structures, are invested by several fascial layers distinct from the Dartos fascia of the scrotal wall.
***** The most superficial layer of the testis and cord is the external spermatic fascia, which is continuous with the external oblique aponeurosis of the superficial inguinal ring.
***** The next deeper layer is the internal spermatic fascia, which is continuous with the transversalis fascia.
***** The Buck fascia covers the erectile bodies of the penis, the corpora cavernosa, and the anterior urethra. The Buck fascia fuses to the dense tunica albuginea of the corpora cavernosa, deep in the pelvis.
***** These fascial layers do not become involved with an infection of the superficial perineal space and can limit the depth of tissue destruction in a necrotizing infection of the genitalia.
** '''<span style="color:#ff0000">Infection travels along the facial planes</span>'''
*** Can extend posteriorly the Dartos fascia to involve the Colles' fascia, but are limited from the anal margin by the attachment of the Colles' fascia to the perineal body.
**** '''<span style="color:#ff0000">Clinical implication: infection limited posteriorly by Colles' fascia</span>'''
*** Can extend along the anterior abdominal wall through a potential space between the Scarpa’s fascia and the deep fascia of the anterior wall (external abdominal oblique).
**** Superiorly, Scarpa’s and Camper’s fasciae coalesce and attach to the clavicles
**** '''<span style="color:#ff0000">Clinical implication: infection limited superiorly by clavicles</span>'''

== Pathogenesis ==

* Infection most commonly arises from the skin, urethra, or rectal regions.
** '''The infection commonly starts as cellulitis adjacent to the portal of entry'''.
* '''<span style="color:#ff0000">Risk factors (8):</span>'''
*# '''<span style="color:#ff0000">Diabetes mellitus</span>'''
*# '''<span style="color:#ff0000">Local trauma</span>'''
*# '''<span style="color:#ff0000">Paraphimosis</span>'''
*# '''<span style="color:#ff0000">Urethral stricture</span>''' associated with sexually transmitted disease resulting in peri-urethral extravasation or urine
*# '''<span style="color:#ff0000">Urethral cutaneous fistula</span>'''
*# '''<span style="color:#ff0000">Peri-rectal or peri-anal infections</span>'''
*# '''<span style="color:#ff0000">Instrumentation</span>'''
*# '''<span style="color:#ff0000">Surgery such as circumcision or herniorrhaphy</span>'''

== Diagnosis and Evaluation ==

* '''History and Physical Exam'''
** Early on, the involved area is swollen, erythematous, and tender as the infection begins to involve the deep fascia. '''Discharge is not present in the early stage.'''
** '''Pain is prominent, and fever and systemic toxicity are marked.'''
** '''Clinical differentiation of necrotizing fasciitis from cellulitis may be difficult because the initial signs including pain, edema, and erythema are not distinctive'''. '''However, <span style="color:#ff0000">marked systemic toxicity and pain out of proportion to the physical exam should alert the clinician.</span>'''
* '''Labs'''
** '''Wound cultures'''
*** '''Generally yield multiple organisms, implicating anaerobic-aerobic synergy'''
* '''<span style="color:#ff0000">Imaging</span>'''
** '''<span style="color:#ff0000">CT pelvis</span>'''
*** '''<span style="color:#ff0000">Sign's of necrotizing fascitis</span>'''
**** '''<span style="color:#ff0000">Subcutaneous gas</span>'''

== Management ==

* '''<span style="color:#ff0000">Urological emergency; requires urgent management</span>'''
** '''<span style="color:#ff0000">Essential interventions in stopping the rapidly progressing infectious process of Fournier's gangrene</span>'''
**# '''<span style="color:#ff0000">Early recognition of the diagnosis</span>'''
**# '''<span style="color:#ff0000">Aggressive surgical debridement</span>'''
**# '''<span style="color:#ff0000">Use of broad-spectrum antibiotics</span>'''
**#* '''<span style="color:#ff0000">Anti-microbial regimens include broad-spectrum antibiotics (β-lactam plus β-lactamase inhibitor) such as piperacillin-tazobactam</span>'''
** '''IV hydration is indicated in preparation for surgical debridement'''
** '''<span style="color:#ff0000">Immediate debridement of skin and involved dartos/scarpa/colle fasica is essential.'''
*** '''Extensive incision should be made through the skin and subcutaneous tissues, going beyond the areas of involvement until normal fascia is found.'''
**** '''Clinical implication: prepare with antiseptic solution widely at the time of surgery (i.e. up to clavicles, down thighs)'''
*** '''Necrotic fat and fascia should be excised, and the wound should be left open.'''
**** '''<span style="color:#ff0000">External, cremasteric, and internal spermatic fasciae are spared</span>'''
***** '''<span style="color:#ff0000">These layers are embryologically distinct from the skin and dartos layers and have their own blood and nerve supplies.</span>'''
*** '''<span style="color:#ff0000">Orchiectomy is almost never required</span>'''
**** '''<span style="color:#ff0000">Testes have their own blood supply independent of the compromised fascial and cutaneous circulation to the scrotum.</span>'''
*** A second procedure 24 to 48 hours later is indicated if there is any question about the adequacy of initial debridement.
* '''Adjunctive procedures''' (should be included in pre-surgical consent)
** '''Suprapubic diversion should be performed in cases in which urethral trauma or extravasation is suspected.'''
** '''Colostomy''' should be performed if there is colonic or rectal perforation.
* Insert figure

== Questions ==

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== Answers ==

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== References ==

* Kim, Ik Yong. "Gangrene: the prognostic factors and validation of severity index in Fournier’s gangrene." ''Gangrene-current concepts and management options''. IntechOpen, 2011.
* Wein AJ, Kavoussi LR, Partin AW, Peters CA (eds): CAMPBELL-WALSH UROLOGY, ed 11. Philadelphia, Elsevier, 2015, vol 2, chap 12