Abstract:Objective To study the meaning of white blood cell(WBC), neutrophil absolute value (NEU), lymphocyte absolute value (LYM), neutrophil/lymphocyte ratio (NLR), high-sensitivity C-reactive protein (hs- CRP) and procalcitonin (PCT) in bloodstream infection caused by Escherichia coli. Methods Totally 50 patients of bloodstream infection caused by Escherichia coli were enrolled and 50 healthy people were collected as the control group. Blood routine, hs-CRP and PCT were measured and compared. The diagnostic value was determined by ROC curve. Results The WBC, NEU, NLR, hs-CRP and PCT of the infection group were higher than that of the control group, and the LYM was lower. There were statistically significant differences in WBC, NEU, NLR and PCT between the two groups (P < 0.05). The area under the curve of NLR in diagnosing bloodstream infection caused by Escherichia coli is 0.728. Conclusions The value of NLR in diagnosing bloodstream infection caused by Escherichia coli is better than that of WBC, NEU, LYM, hs-CRP and PCT. NLR can be combined with PCT as an early diagnostic indicator.