Fournier’s gangrene Dr. Vinod Jain 26.08.2014

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 Ano-rectal causes – infection in the perineal glands Manifestation of colorectal injury, malignancy or diverticulitis Uro-genital causes – infection in the bulbourethral glands urethral injury Iatrogenic injury Lower urinary tract infections

Etiology (contd.) Dermatologic causes – 4. Other less common 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

Pathognomonic findings on pathological evaluation of tissue are :- 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 Restoration of normal organ perfusion Reduction of systemic toxicity Broad spectrum antibiotics to cover anaerobes as well (cipro+clinda+metro) Vancomycin for MRSA Tetanus prophylaxis Irrigation with super oxidised water Hyperbaric oxygen therapy IV immunoglobulins to neutralize super antigen as streptotoxin A & B (as adjuvant) Antifungal – if required 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