Necrotising skin and soft tissue inf

Question 1

Clinical syndromes associated with rapidly necrotising skin and soft tissue infections

Answer 1

necrotising fascitis
myonecrosis
gangrene

Question 2

Causes of necrotising skin and soft tissue inf

Answer 2

Monomicrobial: streptococci, clostridium, staph aureus, vibrio, aeromonas

Polymicrobial:
- Synergistic gangrene: mixed aerobe-anaerobe bacteria
-Fournier gangrene: synergistic gangrene of the genitalia, usually following genital trauma (eg postpartum) or spread from a perianal, retroperitoneal or urinary tract infection
- necrotising infection of the head and neck – generally polymicrobial and can occur in the setting of odontogenic infection or following oropharyngeal surgery or trauma.

Question 3

Clin f of necrotising skin and soft tissue infections

Answer 3

constant severe pain, even if skin inflammation is initially limited
bullae
skin necrosis or bruising
hard (‘wooden’) subcutaneous tissue that is painful on palpation
oedema beyond the margin of erythema
cutaneous anaesthesia
gas in the soft tissues (detected by palpation [skin or soft tissue crepitus] or imaging)
systemic features, including fever, leucocytosis, elevated C-reactive protein (CRP), delirium or acute kidney impairment
rapidly spreading infection.

Question 4

Principles of managing necrotising skin and soft tissue infections

Answer 4

Surgical removal of devitalised tissue and urgent antibiotic therapy are essential for management – multiple debridements are often required. If hyperbaric oxygen therapy is used as an adjunct to surgical debridement, it should not delay surgery.
mpirical antibiotic therapy is used while the pathogen(s) and affected tissues are determined

Question 5

Abx therapy for necrotising skin and soft tissue infection

Answer 5

Depends upon association with water exposure

NOT ASS WITH WATER EXPOSURE
1. meropenem/piperacillin-tazobactam + vancomycin + clindamycin
IVIg can be used if strep pyogenees necrotising fascitis is sus

ASS WITH WATER EXPOSURE
Meropenem + vancomycin + ciprofloxacin + clindamycin
IVIg can be used if strep pyogenees necrotising fascitis is sus