Fournier Gangrene Perineal Necrotizing Fasciitis

Fournier gangrene is a fulminant polymicrobial necrotizing soft tissue infection of the perineum, scrotum, penis, vulva, and adjacent tissues. The microbiology is typically synergistic with mixed aerobic-anaerobic flora including E. coli, Klebsiella, Streptococcus, Bacteroides, Clostridium, and increasingly multidrug-resistant organisms. Mortality remains 20-40% despite advances in management.

Risk factors include diabetes mellitus (40-60%), alcohol use disorder, immunosuppression, perianal abscess or fistula, urethral stricture, recent perianal surgery, malignancy, and chronic kidney disease. Sources include perianal abscess (50%), urogenital infection (35%), and skin trauma (15%). Pathogens spread along Colles, Buck, and dartos fascias to the abdominal wall and chest.

Clinical presentation includes severe pain out of proportion to skin findings, erythema, edema, crepitus, foul odor, skin discoloration progressing to dusky-purple bullae and necrosis, fever, tachycardia, and septic shock. CT shows fascial gas and edema. LRINEC score >=6 raises concern. Management requires immediate broad-spectrum antibiotics (piperacillin-tazobactam, vancomycin, clindamycin for toxin suppression), aggressive surgical debridement within 6 hours with repeat debridements every 24-48 hours, fecal diversion for perianal involvement, ICU support, and reconstruction with skin grafts or flaps after wound stabilization. Hyperbaric oxygen therapy is adjunctive when available.