The Variation And Clinical Value Of Neutrophil Related Biophysical Parameters In Bacterial Infectious Diseases

Infection refers to the pathological process in which pathogen interacts with host under certain conditions after invading the host.Pathogens include bacteria,fungi,parasites,viruses,etc.Infection is the most common type of disease,severe infection is one of the most important causes of death,and effective treatment depend on the identification of clinical type.But there are no specific clinical symptoms and signs of infectious diseases.Although the increase of neutrophils indicates bacterial infection,its cell count is easily disturbed by physiological,drug and other factors.The clinical symptoms of partial infected patients are occult or atypical,in addition,the limitation of doctors' individual clinical thinking and experience makes the diseases difficult to diagnose.So it is urgent to find a proper objective ancillary diagnostic method.Recent studies have found that the change of certain neutrophil biophysical parameters(mean neutrophil volume distribution width,NDW;mean channel of neutrophil volume,MNV;mean conductivity of neutrophil,MNC;mean scattering parameter of neutrophil,MNS)has a clear correlation with infectious diseases and their types.ObjectiveThis study intends to compare the different level of neutrophil biophysical parameters in patients with bacterial infection and healthy people,and to analyze their correlation and differences with PCT,an indicator of bacterial infection,so as to provide simple,quick and immediate reference markers for the early diagnosis,identification and treatment of the most common type of clinical infectious diseases-bacterial infection.Material and methods1.A retrospective study was conducted to collect 368 cases of bacterial infection(included in the experimental group with bacterial infection)diagnosed and treated in the First Affiliated Hospital of Zhengzhou University during Jan to Dec of 2017,to sort and analyse their test results of PCT,the culture of aseptic body fluid(blood,Hydrothorax,cerebrospinal fluid and puncture fluid,et al.),MNV,MNC,MNS,NDW which are detected by VCS(volume conductivity scatter)technology,body temperature,neutrophil count and leukocyte count,and to analyze the results of the same test in 172 healthy volunteers simultaneously(included in the normal control group).2.The correlation between the experimental group and the normal control group were analyzed with statistical method.3.The correlation between leukocyte count,body temperature,neutrophil count,neutrophil biophysical parameters(MNV,MNC,MNS,NDW)and PCT were also analysed and compared in the experimental group with bacterial infection.4.The predicted capability of MNV,MNC,MNS,NDW to bacterial infection is analyzed by the area under the ROC curve,and compared with PCT.Results1.The age composition and the male-to-female ratio of 368 infected patients in the experimental group and 172 healthy persons in control group have no statistical difference;Infected bacteria in the experimental group are mainly Escherichia coli.2.The test results of leukocyte count,PCT,neutrophil count and neutrophil biophysical parameters(MNV,MNC,MNS,NDW)in the experimental group are significantly higher than the control group,and with statistical significance.3.Statistical analysis show that PCT has no significant correlation with body temperature,leukocyte count,neutrophil count(P>0.05),but has correlation with other test(P<0.05),especially with neutrophil biophysical parameters(MNV,NDW)(P<0.01).4.When PCT>0.5?g/L,ROC curve indicates that leukocyte count,body temperature,neutrophil count has a poor predicted capability to bacterial infection,and neutrophil biophysical parameters(MNV,MNC,MNS,NDW)have a better predicted capability.Conclusion1.The neutrophil biophysical parameters(MNV,MNC,MNS,NDW)are significantly correlated with PCT,a specific indicator of bacterial infection,which can be used as a basis for bacterial pathogen infection of body.2.The addition of MNV,MNC,MNS,NDW indicators to routine blood analysis indicators and combination them with the results of WBC count and classification can quickly and accurately diagnose bacterial infectious diseases,which plays an important role in clinical application.