The Role Of HNL, PCT, CRP In The Diagnosis Of Early Bacterial Infection

Infection is a common disease which threats human health. Bacteria and virusesare the main pathogens. The symptoms of patients with infection of bacteriaand viruses usually become heavily and are similar with each other. It is difficult tomake differential diagnosis. In order to control infection and reduce the damage tosystemic organs, doctors often combine application of antibiotics which inhibitbacteria and viruses. This combined application of antibiotics finally led to theincreased resistance of pathogens and weaken the effectiveness of antibiotics.Now the commonly used clinical detection projects, including complete bloodcount, erythrocyte sedimentation rate and C reactive protein, have a low sensitivityand specificity in diagnosis of infective diseases, but also can not make adistinguish among different pathogenic bacteria effectively.The Sweden research group of Venge P discovered human neutrophil lipocalin(HNL) in1994, the gene fragment is5869bp. HNL has178amino acid residues, themolecular weight is25KD. This protein exists in three forms: monomer, homologousand heterologous dimerization of two two mer. In healthy adult serum HNL levels is26.93ng/ml. We can identify the infection type of bacteria and viruses effectively withthe help of HNL. The sensitivity and specificity of HNL is higher thanconventional clinical items, such as WBC or CRP. Pharmacokinetic studies foundthat the expression level of serum HNL decreased rapidly in patients with thebacterial infection after antibiotic treatment, while CRP decreased less, so HNL canbe used as a marker for monitoring the effectiveness of antibiotics. Furthermore, thegold standard in the differential diagnosis of pathogens, the separation and culture ofpathogens usually cost too much time and money, so the clinical utility is limited.Above all, a new index which can provide a fast, accurate, convenient operation inlaboratory has important clinical significance for clinical practice. Purpose：We detected the serum level of HNL, PCT and CRP in infective patients andobserved the role of HNL, PCT and CRP in the diagnosis of early bacterial infection.Methods：We choosed320cases of patients with infective diseases in our hospitalfrom October,2013to October,2014. We made the diagosis according to the clinicalperformance, laboratory findings and imaging examination, bacterial infection in163patients and virus infection in157patients.129healthy college students who gotphysical examination in our hospital were randomly selected as control group.Enzyme-linked immunosorbent assay (ELISA), chemiluminescence, Immuni-zation rate method were used respectively for determinating the serum levelsof HNL, PCT, CPR in patients and to evaluate the diagnostic efficacyResult：the serum level of HNL, PCT and CRP in patients1bacterial infection group and viral infection group and the changes of HNLand PCT, CRP, WBC level in serum of control groupCompared with control group and viral infection group, the concentrationof HNL, PCT, CRP, WBC were all increased in bacterial infection group, andthe concentration of HNL increased significantly (P<0.05); but the concentrationsof HNL and PCT, CRP, WBC in virus infection group did not change significantlycompared with the control group (P>0.05).2the serum positive rate of HNL, PCT and CRP in bacterial infection group,viral infection group and control groupCompared with the control group and viral infection group, the positive rate ofHNL, PCT and CRP in bacterial infection group were94.47%,81.59%and70.55%(P<0.05); but the positive rate of HNL, PCT and CRP in viral infection grouphave no significant change (P>0.05) with the control group.3The curve of bacterial infection with three detection indicators of HNL、PCT、CRPThe compare of area three detection indicators of HNL、PCT、CRP, the HNLarea of0.933,PCT area of0.887, CRP area of0.789. HNL of area under the curve is greater than PCT、CRP.4the diagnostic efficacy of HNL, PCT and CRP in bacterial infection group, viralinfection group and control group.The sensitivity of HNL, PCT and CRP were91.2%、78.3%and76.4%; thespecificity were respectively96.7%、90%and76.7%; the accuracy were89.74%,66.18%and52.85%.(P<0.05)Conclusion：We found that the sensitivity of HNL is higher than PCT, CRP through thedetection of HNL, PCT, CRP levels in serum of patients. This will contribute tothe early diagnosis of bacterial infection in clinical practice.