Is Neutrophil Lymphocyte Ratio, Platelet Lymphocyte Ratio or Red Blood Cell Distribution Width Associated with Risk of Mortality in Patients with Necrotizing Fasciitis.

Purpose: Neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), and red blood cell distribution width (RDW) are novel biomarkers to indicate the inflammatory/immune response, and demonstrated to be effective in diagnosis, severity evaluation, and prognosis in a variety of chronic or acute conditions. This study aims to examine whether NLR, PLR and EDW are independently associated with mortality in necrotizing fasciitis (NF).

Methods: This study retrospectively enrolled patients diagnosed with NF and based on vitality status during hospitalization or within 30 days after discharge, survival and non-survival groups were defined. For distinctly comparing NLR, PLR, RDW and others, we enrolled the matched healthy controls of the same age and sex as the survivors of NF in a 1:1 ratio, which constituted the healthy control group. Comparisons were made between three groups. Variables tested with a value < 0.10 were further entered into the multivariate logistic regression model to identify their independent association with mortality.

Results: A total of 281 subjects were included, including 127 healthy controls, 127 survivors, and 27 nonsurvivors with NF, respectively, indicating a mortality rate of 17.5%. ROC analysis showed that the optimal cutoff value for NLR, PLR and RDW was 11.1, 196.0 and 15.5%, respectively, and was tested as significant only for the first two (P < 0.001, = 0.004). Multivariate logistic analysis showed that NLR ≥ 11.1 (OR, 2.51) and PLR ≥ 196.0 (OR, 2.09) were independently associated with an increased risk of mortality in NF patients, together with age ((OR, 1.28, for each 10-year increment), comorbid diabetes mellitus (OR, 2.69) and liver disease (OR, 1.86), and elevated creatinine level (OR, 1.21 for each 10 umol/L elevation).

Conclusion: Elevated NLR and PLR are significant and independent predictors of mortality and can be considered for use when evaluating patients at risk of mortality.