The early predictive value of serum procalcitonin combined blood culture in the early stage of pathogenic bacteria infection

Objective To investigate the early predictive value of serum procalcitonin(PCT) combined blood culture in intensive care unit(ICU) patients with blood infection. Methods Retrospective analysis the clinical data of ICU patients whose blood culture were positive from January 2012 to June 2015 in our hospital. The serum PCT levels of all the patients were detected, and the results were analyzed statistically.Results In 107 cases patients, 62 cases [57.94%(62 / 107)] patients were gram negative bacterial infection,40 cases[37.38%(40 / 107)] patients were gram positive bacterial infection, and 5 cases[4.68%(5 / 107)] patients were fungi infection. There were statistical significance in the difference of PCT levels among gram negative bacterial infection patients, gram positive bacterial infection patients and fungi infection patients(H =9.378,P= 0.000). The PCT level of gram negative bacterial infection patients was higher than that of gram positive bacterial infection patients and fungi infection patients, and PCT level of fungi infection patients was higher than that of gram positive bacterial infection patients, and the differences all had statistical significance(Pall 0.05). The positive rate of 107 cases of infection patients was 78.50%(84 / 107). There were statistical significance in the difference of PCT positive rate among gram negative bacterial infection patients, gram positive bacterial infection patients and fungi infection patients(χ2= 12.635,P= 0.020). The PCT positive rate of gram negative bacterial infection patients was higher than that of gram positive bacterial infection patients and fungi infection patients, and PCT positive rate of gram positive bacterial infection patients was higher than that of fungi infection patients, and the differences all had statistical significance(Pall 0.05). When the cutoff value was 3.15 ng / m L, the area under receiver operating characteristic curve was 0.895, sensitivity was84.0%, specificity was 92.0%, positive predictive value was 91.0%, negative predictive value was 85.0%,positive likelihood ratio was 10.50, negative likelihood ratio was 0.17, Youden index number was 0.76 of PCT level for diagnosing gram negative bacterial infection. Conclusion Serum PCT has high value in the early predict of pathogenic bacteria in ICU patients with blood infection.