Inflammatory Markers as Predictors of Orbital Infection Severity

Purpose: To assess the utility of inflammatory marker levels in defining orbital cellulitis (OC) severity. Methods: A retrospective cohort study was conducted at 2 tertiary care centers using a medical record search of billing codes from January 1, 2000 to January 1, 2023. Patients were categorized into 2 cohorts - uncomplicated OC and OC with complication [subperiosteal abscess (SPA), orbital abscess (OA), or cavernous sinus thrombosis (CST)]. Values at presentation of the following markers were recorded: absolute neutrophil count (ANC), white blood cell count (WBC), platelet count, C-reactive protein (CRP), and neutrophil-to-lymphocyte ratio (NLR). Logistic regression, controlled for immunosuppression and age, compared levels between patients with uncomplicated OC versus OC with complication, surgical versus nonsurgical management, and abnormal versus normal presenting and final vision. Results: A total of 785 patients - 413 uncomplicated OC (52.6%) and 372 OC with complication (47.4%) (272 SPA [73.2%], 85 OA [22.8%], and 15 CST [4.0%]) - met criteria. The sample was majority male (58.2%) and White (65.9%), with a mean age of 31.6 ± 26.4 years. Platelet count, ANC, WBC, and NLR levels were significantly higher in patients with complicated OC (p < 0.001). Levels of ANC, WBC, CRP, and NLR were significantly higher in surgical patients (p < 0.001). Higher levels of NLR and ANC were associated with worse visual acuity and an relative afferent pupillary defect at presentation (p = 0.006 and p = 0.032, respectively) but not at the final follow-up. Conclusions: Levels of NLR, ANC, and WBC at presentation may have clinical utility in identifying severe orbital infections and may aid management.