Outcomes and Predictors of Fungal Necrotizing Soft Tissue Infections

Introduction: Fungal necrotizing soft tissue infections (NSTIs) are often diagnosed late due to the low likelihood, resulting in poor patient outcomes. Traditionally NSTI are treated with emergent surgical debridement followed by serial interventions. Adjunctive antibiotics are aimed at common bacterial infections along with toxin reduction; however, fungal treatment is often delayed. This study aimed to identify predictors, treatment patterns, and outcomes in fungal NSTIs. Methods: A retrospective review of patients with NSTIs (n = 634) from a single tertiary academic center was conducted from 2011 to 2023, with patients stratified by fungal presence in wound cultures. Primary outcomes were mortality along with the number of serial debridement. Secondary outcomes were length of stay, intensive care requirements, acute kidney injury, and 30-days readmission. Logistic regression was utilized to identify predictors of fungal infection. Results: Of 634 patients, 110 (17.4%) had fungal-positive wound cultures, with Candida albicans being the most common (47.3%). Patients with positive fungal cultures more frequently had Type 2 diabetes mellitus (74.5% vs. 61.6%, p = 0.014). Patients with positive fungal wound cultures were more likely to require ≥ 3 operative debridement (p < 0.001), had a longer length of stay (19 vs. 12 d, p < 0.001), require mechanical ventilation (p < 0.001), and had greater 90-days mortality (20% vs. 12%, p = 0.03). Female gender (OR: 1.73, 95% CI: [1.09–2.76], p = 0.021), diabetes mellitus (OR: 1.75, 95% CI: [1.07–2.93], p = 0.030), vasopressor use (OR: 1.71, 95% CI: [1.04–2.81], p = 0.034), and VRE infection (OR: 12.2, 95% CI: [4.16–41.3], p < 0.001) were predictive of fungal infection. Conclusion: Fungal NSTIs are associated with worse patient outcomes. Early empirical antifungal therapy may be considered in high-risk patients, particularly those with diabetes, as part of comprehensive NSTI management.