GetTheDiagnosis.org

Welcome, guest.
Login or Sign up to edit.

Add an entry

Search:
 

Tools

Add a finding for this diagnosis

Add prevalence for this diagnosis

Switch to calculator mode to see positive predictive value

Switch to likelihood ratios

Sort findings by Tag

Sort findings by Differential Diagnosis

Jump To

Sensitive and Specific Findings

Sensitive Findings

Poorly Diagnostic Findings

Necrotizing Fasciitis: Sensitivity and Specificity

Introduction: An extremely deadly soft tissue infection involving the deep fascia. This may be caused by Group A Streptococcus or gas-forming organisms such as Clostridium perfringens.

[Edit Diagnosis] [Merge dx] [Add prevalence]

Tags: Infection Musculoskeletal Tag this Diagnosis.

The sensitivity and specificity of findings for Necrotizing Fasciitis are listed below. See the left navigation bar to change the display.

Sensitive and Specific Findings

Finding SensitivitySpecificity Comments, Study
MRI Edit 100%86%

But based on a more recent paper, sensitivity and specificity are likely lower. Exact values will depend on which imaging findings are considered.

Study: AJR Am J Roentgenol. 1998 Mar;170(3):615-20. PMID: 9490940

Radiology. 2011 Jun;259(3):816-24. PMID: 21406630

Sensitive Findings

Finding SensitivitySpecificity Comments, Study
CT Scan Edit 100%81%

Versus non-necrotizing soft tissue infections. (Gold standard - surgery and pathology.)

From the article: Four elements consistent with NSTI were sought in particular: (1) asymmetrical and diffuse areas of soft tissue inflammation and ischemia, (2) muscle necrosis, (3) gas across tissue planes, and (4) fluid collections. The test (CT) result was considered positive for NSTI if it identified inflamed and ischemic or necrotic soft tissues with or without gas and fluid collections. It was considered negative if no such findings were reported.

Study: Arch Surg. 2010 May;145(5):452-5. PMID: 20479343

Leukocytosis or Hyponatremia Edit 90%76%

admission WBC > 15.4 x 10(9)/L or serum sodium [Na] < 135 mmol/L

Study: J Am Coll Surg. 2000 Sep;191(3):227-31. PMID: 10989895

Poorly Diagnostic Findings

Finding SensitivitySpecificity Comments, Study
Laboratory Risk Indicator in Necrotising Fasciitis Edit 80%67%

LRINEC >= 6

http://www.mdcalc.com/lrinec-score-for-necrotizing-soft-tissue-infection/

Study: Anaesth Intensive Care. 2009 Jul;37(4):588-92. PMID: 19681416

Crit Care Med. 2004 Jul;32(7):1535-41. PMID: 15241098