BACKGROUND: Sepsis in elderly patients is a major cause of morbidity and mortality in the clinical setting. The aim of this study was to assess the diagnostic significance of volume conductivity scatter (VCS) parameters and to compare their reliability with that of inflammatory markers. METHODS: Patients (N=85) were divided into 3 groups according to their clinical history and culture results: control (N=29), localized infection (N=38), and sepsis (N=18). VCS parameters were obtained using a UniCel DxH 800 Coulter system. Cut-off values were established based on receiver operator characteristic (ROC) curves. RESULTS: The mean volumes of neutrophils (MNV) and monocytes (MMV) were higher in the sepsis group than in the localized infection and control groups (P=0.000 for both). The mean cell conductivity and low median angle light scatter of neutrophils were lower in the sepsis group than in the localized infection and control groups (P=0.029 and P=0.022, respectively). With a cut-off of 156.5, MNV had a sensitivity of 83.3% and a specificity of 78% in predicting sepsis. CONCLUSION: MNV and MMV, which can be obtained easily using an automated blood analyzer, may be promising hematologic parameters for distinguishing elderly individuals with and without sepsis and may help clinicians in the diagnosis of sepsis.