Demographics, Microbiology and Outcome in Necrotizing Soft Tissue Infections

Abstract

Background: Necrotizing soft tissue infections (NSTI) are potentially severe infections that have a high morbidity and mortality even with modern medical care. This study examines factors associated with outcomes in patients with NSTI in an academic tertiary care hospital. Design: This is a retrospective cohort study of patients admitted with NSTI between 2003 and 2008. Baseline demographics and comorbid conditions, laboratory and clinical parameters, timing of surgery, and outcomes, including length of stay and mortality, were compared with univariate analysis; significant factors were then analyzed for their effects on mortality using binary logistic regression analysis. Results: Sixty-nine patients with NSTI were analyzed; 61% were men. Diabetes (39%) was the most common comorbid condition. Most infections (55%) were polymicrobial. The most common organism in monomicrobial infections was Staphylococcus aureus, and 50 % of these isolates were methicillin resistant. Nine patients (13%) required amputation. Mortality was 20%, and the most significant predictor of mortality was a higher respiratory rate on admission (p=0.02). Conclusion: Patients in this series frequently had diabetes, usually had polymicrobial infections, and had a 20% mortality rate.