Vol.69 No.5 September 2021

Evaluation of neutrophil parameters for the diagnosis of sepsis

Natsuki Narumi¹⁾, Takashi Kondo¹⁾, Ryousuke Moriai¹⁾, Akemi Endo¹⁾, Kouichi Asanuma¹⁾, Yoshihiro Fujiya²⁾ and Satoshi Takahashi^{1, 2)}

¹⁾Division of Laboratory Diagnosis, Sapporo Medical University Hospital, 291, South-1, West-16 Chuo-ku, Sapporo, Hokkaido, Japan
²⁾Department of Infection Control and Laboratory Medicine, Sapporo Medical University School of Medicine

Abstract

The significance of neutrophil parameters for the diagnosis of sepsis was evaluated. The neutrophil parameters were measured using an automated multi-item blood cell analyzer, Sysmex XN-20, and the peripheral blood smears were stained using an automated slide stainer, Sysmex SP-50. Six parameters (NE-WX, NE-WY, NE-WZ, NE-SSC, NE-SFL, and NE-FSC) were investigated and their effects were calculated using XN-20. The values of the neutrophil parameters in the sepsis group were significantly higher than those in the healthy control group. In the sepsis group, the NE-WZ was significantly higher in patients with disseminated intravascular coagulation (DIC) than in those without DIC. NE-WY and NE-SFL showed a very high differentiation ability for sepsis (area under the curve=0.995). Logistic regression analysis indicated that the variations in NE-WY, NE-SFL, and NE-FSC were independent predictors of sepsis. In addition, the blood smears of patients with sepsis showed toxic changes of the neutrophils and larger neutrophils (18-20 μm) as compared to those of the healthy volunteers, which is consistent with the above-mentioned findings. We confirmed the repeatability and temporal stability of NE-WY and NE-SFL, which indicates their potential usefulness in clinical settings. However, there were no significant differences in the NE-WY or NE-SFL among the patients with sepsis, bacteremia, and focal infection. Although it is difficult to differentiate sepsis from bacteremia and focal infection, the aforementioned parameters are easily and expeditiously calculated from the data of a complete blood count at no additional cost. Further investigation is needed to determine the precise usefulness of these parameters in the diagnosis of sepsis.

Key word

sepsis, blood culture, neutrophil parameters, DIC

Received

January 19, 2021

Accepted

May 24, 2021

Jpn. J. Chemother. 69 (5): 367-375, 2021