see also [[Fournier's gangrene]] see [RACGP necrotising soft tissue infection](https://www1.racgp.org.au/ajgp/2021/august/necrotising-soft-tissue-infection), [ Rosen skin and soft tissue infections](x-devonthink-item://0A94947F-64C8-4BD8-81CD-21DEA20B3F5F) # Overview *necrotizing fasciitis:* rapidly progressing necrotising infection that is primarily confined to the skin, subcutaneous tissues, and deep fascia *gas gangrene:* also known as clostridial myonecrosis is a rapidly progressing necrotising infection that involves the muscles ## organisms - sterptococci esp *strep pyogenes GAS* - clostridia - gas-gangrene caused by exotoxin-producing clostridial species - CO2 and H2O are end products of aerobic metabolism - *clostridium perfringes* causes 80-95% of gas gangrene - polymycrobial - eg e coli, bacteroides fragilis, etc [water-associated organisms](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10340249/): - *vibrio vulnificus* -- eg from oysters or salt water - *aeromonas* - fresh and brackish water - others ## risk factors - diabetes - immunosuppression - chronic disease - obesity - PVD - [[IVDU issues|IVDU]] - chronic [[Alcohol-related disease|alcohol use]] - elderly - [[Aboriginal health|aboriginal and torres strait islander]] ## Clinical exam - may have fever, sepsis, shock ; [[Delirium vs psychosis|delirium]] is common - skin around infection site becomes tense, "wooden" induration - rapid progression of necrotizing skin and soft tissue infection - pain and tenderness is severe - may have cutaneous anaesthesia - *crepetus* on exam due to s/c emphysema (eg gas gangrene) - swelling and oedema - *separation of tissue planes* - bullous lesions and skin ecchymoses # treatment - meropenem 1g IV Q8H - pip-taz possible alternative - vanc 25-3mg/kg loading dose - clinidamycin 600mg IV Q8H (or lincomycin) - *water-contaminated infections*: use cipro 400mg IV Q8H - emergent surgical debridement to prevent amputation [[Hyperbaric oxygen therapy]] may be used as an adjunct after initial treatment and debridement # images ![[Pasted image 20240911132948.png]] extensive s/c emphysema tracking along the fascial planes throughout the foot and distal leg