The utility of the systemic immune inflammation and systemic inflammation response indices in suspected intermediate-risk pulmonary embolism.

Aim: To evaluate the utility of the systemic immune inflammation index (SII) and systemic inflammation response index (SIRI) in diagnosing pulmonary embolism (PE) in emergency medicine.

Methods: We retrospectively reviewed the data of patients who presented to the emergency department and underwent contrast-enhanced computed tomography pulmonary angiography for suspected PE between January 1 and December 31, 2021. In 81/168 patients, the diagnosis of PE was confirmed and in 87/168 it was rejected. The data were analyzed with receiver operating characteristic analysis and binary logistic regression analysis.

Results: Patients with PE had a higher white blood cell count (P<0.001), neutrophils (P=0.002), monocytes (P=0.013), neutrophil/lymphocyte ratio (P<0.001), SII (P<0.001), and SIRI (P<0.001), and a lower lymphocyte count (P=0.002). The SII had a sensitivity of 75.31% and a specificity of 71.26%, while the SIRI had a sensitivity of 82.72% and a specificity of 68.97%. Binary logistic regression analysis showed that the Wells score, D-dimer level, and SII independently influenced the diagnosis of PE.

Conclusion: The SII and SIRI may be used to support the diagnosis of PE in the emergency department.