CD64Infection Index And Procalcitonin As Diagnostic Markers Of Bacterial Infections In Elderly Patients With AECOPD

Background:With China’s rapidly aging population, AECOPD presents a rapid increase of incidence in elder patients.Such patients are often accompanied by the sharp deterioration in lung function, seriously affecting the quality of life, and even leading to death. AECOPD is usually triggered by the upper respiratory tract, trachea-bronchial infection and air pollution, including bacterial infection accounted for the occurrence of AECOPD40%-50%. Because the etiological diagnosis is not available in the early time, lag, empirical antibacterial therapy is still conducted in AECOPD patients.Objective:Exploration of the markers of bacterial infections has clinical significance for treatment. PCT,commonly used in the diagnosis of AECOPD infection, is one of the important indicators of inflammation. CD64expression on neutrophils increased significantly during bacterial infection, with higher specificity and sensitivity than that of other inflammatory index,indicating its certain application value in the diagnosis of infectious diseases.Methods:In this study,we enrolled66AECOPD patients from January2013to January2014in our hospital, according to the lower respiratory tract sputum pathogenic bacteria concentration≥107cfu/ml diagnostic criteria for respiratory tract bacterial infection of AECOPD.Then the patients were divided into AECOPD bacterial infection group (n=38) and non bacterial infection group (n=28), a healthy control group (n=30). Before treated with conventional therapy oxygen, antibiotics, cough medicine and mycolytics, we collected blood and sputum samples from all the patients. CD64expression intensity on neutrophil was detected by flow cytometry before and after treatment, then CD64infection index was acquired. Serum procalcitonin (PCT) were measured by immunofluorescence double antibody sandwich method.Results:The CD64index and PCT levels in the bacteria-infected group were significantly higher than these in the other two groups(P<0.05).The CD64index and PCT levels in the non-bacteria-infected group and control group had no significant differences(P<0.05).After treatment, CD64index in the bacteria-infected group decreased significantly (P<0.05), and the CD64index and PCT levels in the bacteria-infected group and control group had no significant difference(P<0.05).Conclusion:The serum CD64and PCT are both sensitive indexes for early identification of bacterial infection. Combined detection of the two indicators may increase the diagnostic accuracy of AECOPD bacterial infection and be benefit for differential Diagnosis.