Necrotizing soft tissue infections: Difference between revisions

Latest revision as of 19:22, 21 May 2025

Background

Abbreviation: NSTI
Includes necrotizing forms of cellulitis, myositis, and fasciitis

General types

Type 1: polymicrobial infection
Type 2: group A strep
- May occur in healthy individuals
- May occur via hematogenous spread from throat to site of blunt trauma

NSTI Types

Clinical Features

Nectrotizing fasciitis

Differential Diagnosis

Skin and Soft Tissue Infection

Look-A-Likes

Sporotrichosis
Osteomyelitis
Deep venous thrombosis
Pyomyositis
Purple glove syndrome
Tuberculosis (tuberculous inflammation of the skin)

Necrotizing rashes

Evaluation and Management

See specific type:

NSTI Types

External Links

MDCalc - LRINEC Score

References

Authors:

@@ Line 1: / Line 1: @@
 ==Background==
-* Includes necrotizing forms of cellulitis, myositis, and fasciitis
+*Abbreviation: NSTI
-* Two types:
+*Includes necrotizing forms of cellulitis, myositis, and fasciitis
-** Type 1: polymicrobial infection
-** Type 2: group A strep
-*** May occur in healthy individuals with no PMH
-*** May occur via hematogenous spread from throat to site of blunt trauma
-==Necrotizing Fasciitis==
-===Risk Factors===
-*DM
-*Drug use
-*Obesity
-*Immunosuppression
-*Recent surgery
-*Traumatic wounds
-===Clinical Features===
+===General types===
-*Skin exam
+*Type 1: polymicrobial infection
-**Erythema(without sharp margins)
+*Type 2: [[group A strep]]
-**Exquisitely tender (pain out of proportion to exam)
+**May occur in healthy individuals
-**Skip lesions
+**May occur via hematogenous spread from throat to site of blunt trauma
-**Hemorrhagic bullae
-***May be preceded by skin anesthesia (destruction of superficial nerves)
-**Crepitus (in type I infections)
-*Swelling/edema may produce compartment syndrome
-*Constitutional
-**Fever
-**Tachycardia
-**Systemic toxicity
-===Work-Up===
+{{NSTI types}}
-*Labs
-**CBC
-**Chem
-**PT/PTT/INR
-**CK
-**Lactate
-*Imaging
-**CT
+==Clinical Features==
+[[File:NectrotizingFasciitis.jpeg|thumb|Nectrotizing fasciitis]]
-===Diagnosis===
+==Differential Diagnosis==
-*Surgical exploration is the only way to definitively establish the diagnosis of necrotizing infection
+{{SSTI DDX}}
-*Imaging
+{{Necrotizing Rashes DDX}}
-**Should not delay surgical exploration
-**CT
-***
-==Necrotizing Myositis==
+==Evaluation and Management==
-* Much rarer than nec fasc
+See specific type:
-* May be preceded by skin abrasions, blunt trauma, heavy exercise
-* Most patients are otherwise healthy (DM and other underlying conditions do not appear to increase risk)
-===Clinical Features===
+{{NSTI types}}
-*Exquisite pain and swelling of affected muscle with induration
-*Overlying skin changes may manifest later in the course of illness (erythema, warmth, petechiae, bullae)
-*Hypotension may occur rapidly with development of streptococcal toxic shock syndrome
-==Necrotizing Cellulitis==
+==See Also==
-*Pts are often much less toxic compared with nec fasc/nec myo
+*[[Necrotizing rashes]]
-* Two types:
-**Anaerobic infection (clostridial and nonclostridial)
-**Meleney's synergistic gangrene
-***Rare infection that occurs in postop pts
-***Characterized by slowly expanding indolent ulceration that is confined to superficial fascia
-***Results from synergistic interaction between S. aureus and microaerophilic streptococci
-===Risk Factors===
+==External Links==
-*Trauma
+*[http://www.mdcalc.com/lrinec-score-for-necrotizing-soft-tissue-infection/ MDCalc - LRINEC Score]
-*Surgical contamination
-*Spread of infection from bowel to perineum, abdominal wall, or lower extremities
-===Clinical Features===
+==References==
-*Thin, dark, sometimes foul-smelling wound drainage (often containing fat globules)
+<references/>
-*Tissue gas formation (crepitus)
-===Management===
-*Surgical exploration and debridement required to distinguish between anaerobic cellulitis and fasciitis or myonecrosis
-==Treatment==
-#Surgical exploration and debridement
-##Indicated in setting of severe pain, toxicity, fever, elevated CK, w/ or w/o radiographic evidence
-#Abx
-##Must cover Gram +/- and anaerobes (esp GAS and clostridium)
-##Piperacillin-tazobactam 3.375-4.5g q6hr AND clindamycin 600-900mg q8hr AND vancomycin 1gm IV q12hr
-==Source==
-* UpToDate
 [[Category:ID]]