Evaluation of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for detecting necrotizing soft tissue infections in patients with diabetes and lower extremity infection

Aims: The aim of this pilot study was to assess the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC), a scoring system for Necrotizing Soft Tissue Infections, to diagnose Necrotizing Soft Tissue Infections of the lower extremity in patients with diabetes. Methods: Sixty-nine patients with lower extremity infections were prospectively enrolled. The Laboratory Risk Indicator for Necrotizing Fasciitis was calculated and logistic regression was performed for each laboratory value. Results: The Laboratory Risk Indicator for Necrotizing Fasciitis was associated with Necrotizing Soft Tissue Infection diagnosis in patients with diabetes (p = 0.01). Sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 69%, 16.6%, and 100% respectively. Elevated C-reactive protein (OR 1.01, p = 0.02, 95% CI [1.002-1.23]) and white blood cell count (OR 1.34, p < 0.01, 95% CI [1.1-1.7]) were associated with Necrotizing Soft Tissue Infection. Conclusions: The Laboratory Risk Indicator for Necrotizing Fasciitis was useful as a negative predictor of Necrotizing Soft Tissue Infection while C- reactive protein and white blood cell count may have value as individual predictors. We recommend high clinical suspicion of Necrotizing Soft Tissue Infections in diabetics as laboratory evaluation may be non-specific. (C) 2020 Elsevier B.V. All rights reserved.