The value of neutrophil volume and monocyte volume in distinguishing and predicting local infection and bloodstream infection

WU Xiangyun; ZHANG Han

doi:10.3969/j.issn.1002-7386.2016.06.003

Abstract：Objectives To investigate the value of mean neutrophil volume ( MNV ) and its distribution width standard deviation ( NDW-SD ) as well as mean monocyte volume ( MMV ) and its distribution width standard deviation ( MDW-SD) in distinguishing and predicting local infection and bloodstream infection .Methods Sixty healthy subjects were randomly selected in the study (control group),whose blood routine parameters were within normal reference ranges .The 58 patients with local infections including pneumonia , urinary tract infections , acute appendicitis were served as local infection group,and their blood routine test results on 2 day before and after diagnosis were collected .Besides the other 57 patients with positive blood culture were served as bloodstream infection group ,and their blood routine test results on the day of specimens being delivered and tested and on 2 days before and after testing were collected .The levels of MNV ,NDW-SD,MMV,MDW-SD were analyzed and compared among the three groups .Moreover the blood routine test results of 31 patients in bloodstream infection group during 3~7 days before the blood specimens were delivered and tested were compared with those on the day of specimens being delivered and tested and on 2 days before and after testing .Results There were significant differences in MNV,NDW-SD,MMV,MDW-SD among three groups ( P <0.05).However there were no significant differences between the results during 3~7 days before the blood specimens were delivered and tested and the results on the day of specimens being delivered and tested and on 2 days before and after testing in bloodstream infection group ( P >0.05),furthermore, there were significant differences only in MNV and NDW-SD between bloodstream infection group and local infection group (P<0.05).The ROC area under curve of MNV and NDW-SD in distinguishing early local infection from bloodstream infection (3 ~7d before testing) was 0.728, 0.827,respectively,when MNV≥153.5, its sensitivity and specificity was 0.581,0.914,respectively, however, when NDW-SD≥18.42, its sensitivity and specificity was 0.839,0.759,respectively, with higher sensitivity and specificity .The 4 indexes including MNV ,MMV,NDW-SD,MDW-SD played an important role in distinguishing local infection from bloodstream infection , with ROC area under curve being 0.67,0.625,0.771,0.641, respectively.Conclusion The MNV, NDW-SD, MMV and MDW-SD have a potential clinical application value in distinguishing local infection from bloodstream infection .The MNV and NDW-SD are obviously increased during 3~7 days before specimens are delivered and tested , which may suggest bloodstream infection .