Systemic immune-inflammation index (SII) as a predictor of mortality in patients with sepsi

Authors

  • Rini Roslaeni Department of Clinical Pathology, Faculty of Medicine, Universitas Jenderal Achmad Yani, Cimahi, Indonesia.
  • Fathul A Imtinan Undergraduate Medical Program, Faculty of Medicine, Universitas Jenderal Achmad Yani, Cimahi, Indonesia.
  • Yuke Ireka Department of Anatomical Pathology, Faculty of Medicine, Universitas Jenderal Achmad Yani, Cimahi, Indonesia.
  • Hapsari Fujiyanti Laboratory of Clinical Pathology, Oto Iskandar Di Nata Hospital, Bandung, Indonesia.

Keywords:

Mortality predictor, sensitivity of SII, sepsis, SII cut-off, systemic immuneinflammation index

Abstract

Sepsis is one of the leading causes of hospital mortality. Simple biomarkers capable of predicting mortality in patients with sepsis are therefore highly needed. The systemic immune-inflammation index (SII), calculated from hematological parameters including neutrophil, platelet, and lymphocyte counts, has been proposed as a potential prognostic indicator in sepsis. This study aimed to evaluate the ability of SII to predict mortality in patients with sepsis and to determine its optimal cut-off value. This retrospective study was conducted using medical record data from 62 patients with sepsis, comprising 31 survivors and 31 non-survivors. Hematological data used to calculate the SII were obtained from intensive care unit (ICU) medical records at Oto Iskandar Di Nata Hospital from January to December 2025. The SII was calculated using the formula: platelet count × neutrophil count / lymphocyte count. Receiver operating characteristic (ROC) analysis was performed to determine the area under the curve (AUC), sensitivity, specificity, and optimal cut-off value. The optimal SII cut-off value was 445.5. ROC analysis demonstrated an AUC of 95.4%, with a sensitivity of 96.8% and a specificity of 83.9%. Logistic regression analysis showed an odds ratio (OR) of 15.2 (95% CI: 5.8–39.7; p < 0.001). These findings suggest that SII reflects systemic inflammatory activity, with higher values associated with an increased risk of mortality. SII is a simple, accessible, and inexpensive biomarker with high predictive accuracy for mortality in patients with sepsis. An SII cut-off value of 445.5 may be useful as a risk indicator for identifying patients with sepsis who are at high risk of death.

 

DOI :  10.35990/amhs.v5n1.p41-49

 

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Published

2026-06-30

How to Cite

Roslaeni, R. ., Imtinan, F. A. ., Ireka, Y. ., & Fujiyanti, H. . (2026). Systemic immune-inflammation index (SII) as a predictor of mortality in patients with sepsi. ACTA Medical Health Sciences, 5(1), 41–49. Retrieved from http://amhs.unjani.ac.id/index.php/acta_medica/article/view/132

Issue

Vol. 5 No. 1 (2026): ACTA Medical Health Sciences

Section

Articles