Derived Neutrophil-to-Lymphocyte and Neutrophil-to-Platelet Ratios Distinguish Sinusitis-Related Orbital Cellulitis From Periorbital Necrotizing Fasciitis.

Purpose: Periorbital necrotizing fasciitis (NF) and sinusitis-related orbital cellulitis (OC) present with common clinical features, although the management algorithms for these ailments vary considerably. Previous investigations have failed to identify biomarkers that distinguish between these entities. This study was designed to explore the role of the derived neutrophil-to-lymphocyte and neutrophil-to-platelet ratios in discerning NF from OC.

Methods: The derived neutrophil-to-lymphocyte and neutrophil-to-platelet ratios were calculated in nonimmunocompromised adult patients with NF and OC from the first blood draw upon presentation to the emergency department at a single academic medical center. Mann-Whitney nonparametric analyses and the area under the receiver-operator curve were analyzed via a dedicated computerized software package.

Results: A total of 16 patients with NF (mean age = 54.5 years) and 12 patients with OC (mean age = 50.8 years) were identified. The mean derived neutrophil-to-lymphocyte ratios were 5.74 (standard deviation = 4.20) and 2.36 (standard deviation = 1.75) for NF and OC, respectively (p = 0.0037), resulting in an area under the receiver-operator curve of 0.82 (95% confidence interval = 0.66-0.98). The mean neutrophil-to-platelet ratios were 0.073 (standard deviation = 0.044) and 0.020 (standard deviation = 0.0084) for NF and OC, respectively (p < 0.001), yielding an area under the receiver-operator curve of 0.92 (95% confidence interval = 0.80-1.00).

Conclusions: In nonimmunocompromised adult patients, the derived neutrophil-to-lymphocyte ratio and neutrophil-to-platelet ratio both appear to distinguish NF from OC. While further study is required in larger cohorts to ensure the robustness of these findings, these initial results suggest that these biomarkers may be coupled with appropriate examinations to diagnose patients with these conditions and initiate the appropriate steps in the management of patients with orbital infectious disease.