Role of Automated Volume, Conductivity and Scatter (VCS) Parameters of Neutrophils as Indicators of Sepsis

This study was done to evaluate the role of automated volume, conductivity and scatter (VCS) parameters of neutrophils as indicators of sepsis and its differentiation from other inflammatory disorders. In this cross-sectional study, 225 patients with culture proven or with clinical evidence of sepsis were included along with an equal number of healthy controls. In addition, 138 patients with non-infective inflammatory conditions-acute pancreatitis (50), burns (45) and acute myocardial infarction (43) were also included. Complete blood count was done on LH750 automated hematology analyser (Beckman Coulter). VCS data; mean neutrophil volume (MNV), mean neutrophil conductivity (MNC) and mean neutrophil scatter (MNS) for all patients was recorded. MNV was high (p < .0001) while MNS was lower (p < .0001) in patients with sepsis compared to the control group. MNC was comparable between the two groups (p = .4735). On subgroup analysis of patients with sepsis, significant difference in MNV (p = .0009) and MNS (p = .0210) was observed in patients with leukopenia, normal TLC and leucocytosis. Youden Index was maximum (71%) at MNV of 144.6 (sensitivity-82.7%; specificity-88.5%) and MNV of 147.9 (sensitivity-75.6%; specificity-95.6%) for sepsis. On comparing patients with sepsis with acute pancreatitis and myocardial infarction, MNV and MNC were significantly higher in patients with sepsis. MNV is a useful, inexpensive parameter which can be accessed during a routine CBC run from the raw data. It can be utilized as an early indicator of sepsis as an adjunct to the clinical diagnosis in suspect patients. However, its availability in only select hematology analyzers may limit its use.