Abstract: Objective  To investigate the value of  blood routine (BR)  combined with Creactive protein (CRP) and procalcitonin (PCT) in neonatal sepsis diagnosis. Methods  The serum levels of WBC， PLT， CRP and PCT were detected in 72 patients with neonatal sepsis and 80 patients with nonsepsis. The degree of critical illness (neonatal critical illness scoring， NCIS) were achieved， the correlation between WBC，PLT，CRP，PCT and NCIS were analyzed.  The ROC curves were used to evaluate the values of the three parameters in the diagnosis of neonatal sepsis. Results  Serum levels of WBC，N%，PCT， CRP and WBC were significantly higher in the sepsis group than nonsepsis group， but serum PLT was significantly lower in sepsis group than nonsepsis group (P<0.01). There was positive correlation between PLT and NCIS， negative correlation between PCT and NCIS， but no correlation between WBC， N， CRP and NCIS in neonatal sepsis group before treatment.The area under receiver operating characteristic curve (AUC) of WBC， CRP and PCT were 0.89， 0.88 and  0.978，but the AUC of three biomarkers for the diagnosis of neonatal sepsis was 0.998. Conclusion  BR， CRP combined with PCT plays an important role in the diagnosis of neonatal sepsis.

Key words: hemorrhagic septicemia；leukocytes , blood platelets, Creactive protein, procalcitonin, neonatal