An acute, usually rapidly progressive, necrotizing soft tissue infection. Often anesthetic over the infection. It can involve the skin (cellulitis), the muscle (myositis) and/or fascia (fasciitis). From a practical point of view, it is the surgeon who decides the extent of infection when she debrides it. I am soooo PC.
- Aeromonas hydrophilia: after fresh water trauma or use of leeches. Really. The plastic surgeons use leeches and the leech requires Aeromonas to exist in its gut to live. Once you treat the aeromonas, the leech will die.
- Gas Gangrene: C. perfringens.
- Group A Streptococcus: especially with prior NSAID use or trauma.
- Staphylococcus aureus: especially MRSA that makes the Panton-Valentine leukocidin. In some series it is the most common cause of nec fasc (Ref). Cirrhotic patients (in Taiwan) had monomicrobial infections mainly by gram-negative rods (GNBs) (76%), including Vibrio (36%), Klebsiella (21%), and Aeromonas spp. (14%) (PubMed).
They all require debridement. Then
- Mixed synergistic necrotizing fasciitis: (third generation cephalosporins PLUS metronidazole) OR carbapenems OR (quinolone PLUS metronidazole) OR penicillin/beta-lactamase inhibitors ALL SELECTIONS +/- aminoglycosides if septic.
- Group A Streptococcus: Penicillin PLUS clindamycin PLUS 1g/kg IVIG day one, 0.5 g/kg day 2 and 3. Why? The Eagle effect, where high inoculum of Group A Strep are resistant to pencillin and patients do better on clindamycin (PubMed). Plus I do have an affinity for screwing with bacterial virulence factors aka proteins.
While IVIG is (relatively) proven for streptococcal toxic shock syndrome, it's use for Strep and staph necrotizing soft tissue infection is not proven. I am a believer in IVIG in these circumstances.
Hyperbaric you ask? I remain skeptical. If you are going to use it, use AFTER debridement and AFTER antibiotics. I remember once I was asked by a doctor what I thought about hyperbaric. I said it was great for the bends, but primarily served to make hyperbaric doctors richer. Why do you ask? Turns out he was the medical director of the hyperbaric chamber. Oops. Open mouth, insert foot.
Relevant links to my Medscape blog
Last Update: 04/28/18.