Review Question - QID 104216

This patient is suffering from necrotizing fasciitis given his fever, rapidly progressive rash, and immunosuppression (from untreated diabetes). He needs empiric broad antibiotic coverage (with vancomycin, piperacillin-tazobactam, and clindamycin as an appropriate regimen) and surgical debridement.

Necrotizing fasciitis is a rapidly progressive bacterial infection of the deep soft tissues. Organisms involved include Streptococcus pyogenes, Staphylococcus aureus, mixed anaerobes, and gram-negative rods. Bacteria are generally introduced into the soft tissues during surgery, minor trauma (such as a small puncture wound), or any open trauma. The infection is more common in immunosuppressed patients such as diabetics, transplant patients, or patients with HIV. The infection can progress over minutes to days and results in profound tissue damage and death. Physical exam may reveal crepitus; however, this is not a necessary finding to make the diagnosis since many organisms do not produce gas. The appropriate treatment involves coverage for MRSA (vancomycin), a carbapenem or beta-lactam + beta-lactamase inhibitor, and clindamycin for toxin suppression. Patients must also undergo surgical debridement as there is nearly a 100% mortality without a surgical intervention. The wound can then be kept under vacuum and carefully monitored.

Figure A depicts necrotizing fasciitis in the left leg. Note the purplish discoloration of the skin surrounded by an area of cellulitis.

Incorrect Answers:
Answer 1: Ceftriaxone is an appropriate IV antibiotic that can be given for cellulitis that is refractory to oral antibiotics. If this patient had a slowly spreading red and warm leg without systemic symptoms, then oral cephalexin could be given first followed by ceftriaxone if not responsive to this oral antibiotic.

Answer 2: Vancomycin and ceftriaxone is a broad-spectrum antibiotic that covers for MRSA and skin flora. Vancomycin would be added to treatment if the patient presented with cellulitis refractory to treatment and an abscess. These antibiotics would be given after incision and drainage of the abscess.

Answer 3: Vancomycin, cefepime, clindamycin, and surgical debridement is a broad-spectrum regimen; however, a carbapenem or beta-lactam + beta-lactamase inhibitor must be given for necrotizing fasciitis.

Answer 4: Vancomycin, cefepime, piperacillin-tazobactam, and surgical debridement is a broad-spectrum regimen; however, it misses out on the toxin suppression of clindamycin.

Bullet Summary:
The treatment of necrotizing fasciitis is broad-spectrum antibiotics (with coverage for MRSA, toxin suppression with clindamycin, and a carbapenem or beta-lactam + beta-lactamase inhibitor) in addition to surgical debridement.