Tularemia caused by Francisella tularensis, is characterized by a complex interplay between the pathogen and the host’s innate immune system. This study aimed to evaluate the diagnostic potential of serum interferon regulatory factors (IRFs) and their association with clinical outcomes in patients with tularemia. In this prospective case-control study, 35 adult patients diagnosed with tularemia at Cumhuriyet University Hospital (June–August 2024) and 30 age- and sex-matched healthy controls were enrolled. Serum levels of IRF-1, IRF-2, and IRF-4 were quantified using enzyme-linked immunosorbent assay (ELISA). Among the 35 patients (71.4% female; mean age 45.7±16.7 years), the oropharyngeal form was the predominant clinical presentation (80%). Serum levels of IRF-1, IRF-2, and IRF-4 were significantly higher in the patient group compared to controls (p 0.001). Receiver Operating Characteristic (ROC) analysis demonstrated that all three IRFs possessed high discriminative power between patients and healty controls, with Area Under the Curve (AUC) values exceeding 0.80. Specifically, IRF-2 and IRF-4 exhibited sensitivities and specificities above 90% at optimal cutoff values. No statistically significant correlation was found between IRF levels and treatment failure or the requirement for lymph node dissection (p 0.05). Elevated serum levels of IRF-1, IRF-2, and IRF-4 reflect a robust systemic immune response against F. tularensis. These transcription factors, particularly IRF-2 and IRF-4, show promise as adjunct biomarkers for monitoring host immune activation during tularemia infection.
Bolat et al. (Fri,) studied this question.