Diagnostic value of systemic immune inflammation index in acute appendicitis

Clinical diagnosis of acute appendicitis is often difficult and involves a synthesis of clinical, laboratory, and radiological findings. The aim of this study was to investigate whether the systemic immune inflammation index can be used as an effective parameter in the diagnosis of acute appendicitis and its reliability in the differentiation of complicated vs. non-complicated appendicitis.

The study was conducted retrospectively with patients admitted to the emergency department with abdominal pain and diagnosed with acute appendicitis. In total, 150 patients and 150 control cases were included in the study. Demographic data, medical history, white blood cell count, platelet count, neutrophil count, systemic immune inflammation index values, Alvarado score, adult appendicitis score, and pathology result of appendectomy material were retrieved from the hospital automation system and recorded in the data form.

Neutrophil-lymphocyte ratio and systemic immune inflammation index were significantly higher, and platelet-neutrophil ratio and lymphocyte-neutrophil ratio were significantly lower in the patient group compared to the control group (p<0.001). Receiver operating characteristic analysis revealed that the sensitivity and specificity of systemic immune inflammation index with a cutoff value of 840.13 was 82 and 66.7%, respectively, for the diagnosis of acute appendicitis. Correlation analysis revealed that systemic immune inflammation index, Alvarado score, and adult appendicitis score were positively correlated, and this correlation was statistically significant.

Systemic immune inflammation index may be used to promote the diagnosis of acute appendicitis and may reduce the need for radiation exposure and diagnostic imaging tests such as contrast-enhanced abdominal computed tomography. It can also be used to differentiate between complicated and non-complicated acute appendicitis cases.