Fournier’s gangrene

Dr. Vinod Jain26.08.2014

Fournier’s gangrene• Definition • Etiology & risk factors• Pathogenesis & pathology • Incidence • Clinical features• Differential diagnosis• Investigations• Treatment –

- Medical - Surgical

• Complications

Definition

Named after French venereologist Jean Alfred Fournier (1883). Fournier gangrene is defined as a polymicrobial necrotizing fasciitis of the perineal, perianal, or genital areas.

Etiology & risk factors

• Initially described as idiopathic

• Now in more than 75% cases inciting cause in known

• Necrotizing process commonly originates from infection in anorectum, urogenital tract or skin of genitalia

Etiology

1. Ano-rectal causes –– infection in the perineal glands – Manifestation of colorectal injury,

malignancy or diverticulitis

2. Uro-genital causes –– infection in the bulbourethral glands – urethral injury– Iatrogenic injury – Lower urinary tract infections

Etiology (contd.)

3. Dermatologic causes –– Hidradenitis suppurativa – Ulceration from scrotal pressure– Trauma to scrotum or perineum

4. Other less common causes –– Consequence of bone marrow

malignancy – Systemic lupus erythematosus – Crohn’s diseases

Risk factors

• Diabetes mellitus • Alcoholism • Malignancies• Cirrhosis Liver • Chronic steroid use • HIV infection• Malnutrition• Morbid Obesity

Causative Bacteria

• Polymicrobial infection • Minimum of four isolates per case • Most common aerobe – E. coli• Most common anaerobes – Bacteroids • Others – Streptococcus, Staphylococcus,

MRSA – Methicillin Resistant Staphylococcus aureus, Klebsiella Pseudomonas, Proteus & Clostridium.

Pathogenesis

• Bacteria act synergistically causing obliterative endarteritis & production of various enzymes causing destruction

• There is imbalance between host immunity & virulence of organism

Mechanism of spread Entry of bacteria (act through synergism)

Fibrinoid coagulation of nutrient vessels

Decreased locally blood supply to skin

Decreased tissue oxygen tension

Growth of anaerobes & microaerophilic organisms

Production of enzyme (Collagenase, Lecithinase, Hyaluronidase )

Digestion of fascial barrier

Rapid spread of infection

Pathology

Pathognomonic findings on pathological evaluation of tissue are :-

• Necrosis of superficial & deep fascial planes• Fibrinoid coagulation of the nutrient

arterioles • Polymorphonuclear cell infiltration • Presence of micro organisms with in the

involved tissues• Air in the perineal tissue

Incidence

• Age – 30 – 60 years • Sex – 10 times more common in

males • Social habits – More common in male

homosexuals (more prone for Rectal injury)

Clinical features

• Begins with insidious onset of pruritus and discomfort of external genitalia

• Prodromal symptoms of fever and lethargy, which may be present for 2-7 days before gangrene

• The hallmark of Fournier gangrene is out of proportion pain and tenderness in the genitalia.

• Increasing genital pain and tenderness with progressive erythema of the overlying skin

• Dusky appearance of the overlying skin; subcutaneous crepitation; feculent odor

• Obvious gangrene of a portion of the genitalia; purulent discharge from wounds

• As gangrene develops, pain subsides (Nerve necrosis)

Differential diagnosis

• Balanitis • Cellulitis • Epididymitis• Gas gangrene• Compicated hernias • Complicated hydrocele• Necrotizing fasciitis• Orchitis • Testicular torsion

Other Problems to be Considered

• Testicular fracture• Testicular hematoma• Testicular abscess • Scrotal abscess• Vasculitis• Warfarin gangrenosum• Polyarteritis nodosum • Wegener’s granulomatosis

Investigations

(CBC) Complete blood count Electrolytes BUN / Serum creatinine Blood Sugar ABG Blood and urine culture with sensitivity Coagulation profile for DIC

Investigations (contd.)

Imaging- Conventional radiography Ultrasonography C.T. Scanning MRI

Conventional radiography

• Consider where clinical findings are inconclusive

• Presence of gas in soft tissue

Ultrasonography• Can be used to detect fluid or

gas in soft tissue

• “Sonographic hallmark” – Presence of gas in scrotal tissue

• Excludes other conditions

• Testicular blood flow - N

• Limitations – Direct pressure on involved tissue causes inconvenience

C.T. Scanning

• Can detect smaller amount of soft tissue gas

• Defines extent more specifically • Identifies underlying causes eg.

Small perineal abscess MRI• Yields greater soft tissue details • Create logistic challenges,

especially in critically ill patients

Treatment

• Medical

• Surgical

Medical Treatment 1. Restoration of normal organ perfusion 2. Reduction of systemic toxicity3. Broad spectrum antibiotics to cover anaerobes as well

(cipro+clinda+metro)4. Vancomycin for MRSA5. Tetanus prophylaxis 6. Irrigation with super oxidised water 7. Hyperbaric oxygen therapy8. IV immunoglobulins to neutralize super antigen as

streptotoxin A & B (as adjuvant)9. Antifungal – if required 10. Non – conventional

- Unprocessed honey – enzyme action - dressing with gauge soaked with zinc per

oxide

Surgical treatment

• Repeated aggressive debridement

• Preservation of testes (subcutaneous pocket from desiccation)

• Reconstruction after infection is over

• Fecal diversion

• Urinary diversion

• Vacuum assisted closure (VAC)

Complications

• ARF

• ARDS

• Septicemia and gram negative shock

• MSOF

• Tetanus

• Death

Questions ?

Let us revise• Definition • Etiology & risk factors• Pathogenesis & pathology • Incidence • Clinical features• Differential diagnosis• Investigations• Treatment –

- Medical - Surgical

• Complications