Differentiating Upper Extremity Necrotizing Soft Tissue Infection From Serious Cellulitis and Abscess

Area of Science:

• Infectious Diseases
• Surgical Infections
• Medical Diagnostics

Background:

• Necrotizing soft tissue infection (NSTI) of the upper extremity (UE) is a severe, rapidly progressing infection.
• Early diagnosis and emergent treatment are crucial to prevent limb loss or death.
• Clinical presentation of early NSTI can be indistinguishable from serious cellulitis or abscess.

Purpose of the Study:

• To identify factors differentiating upper extremity NSTI from serious cellulitis or abscess in patients with similar clinical presentations.
• To improve diagnostic accuracy for severe soft tissue infections.

Main Methods:

• Retrospective cohort study comparing UE NSTI patients with UE serious cellulitis or abscess patients.
• Cohorts matched using the Laboratory Risk Indicators for Necrotizing Fasciitis (LRINEC) score.
• Analysis included laboratory values, vital signs, symptoms, and social factors; statistical methods included Mann-Whitney U, chi-squared, Fisher exact, and logistic regression.

Main Results:

• Multivariate analysis identified four factors significantly associated with NSTI:
• Elevated lactate on presentation
• Patient-reported history of fever
• Male gender
• Homelessness

Conclusions:

• Upper extremity NSTI and serious cellulitis/abscess share similar clinical presentations.
• In LRINEC-matched patients, elevated lactate, subjective fever, male gender, and homelessness are significant indicators of NSTI.
• These factors can aid in differentiating NSTI from less severe infections, guiding timely intervention.