Abstract:

Objective To explore the difference of clinical significance of modified neutrophil CD64 （nCD64）index and traditional nCD64 index in diagnosing infection. Methods We include 32 patients with auto⁃ immune diseases（AID），32 patients with hematologic tumors，59 patients in the emergency department and 41 healthy cases.Among which 76 were diagnosed with infection and 47 were non ⁃infected. Fluorescence intensity of CD64 on the peripheral blood lymphocytes，monocytes and neutrophils was detected by flow cytometry. The modi⁃ fied nCD64 index and the traditional nCD64 index were calculated and were used to make a ROC analysis. Results The modified nCD64 index and the traditional nCD64 index in infected patients were significantly higher than those in non⁃infected patients and healthy control（all P < 0.05）. The AUCs of modified nCD64 indexes and traditional nCD64 index were 0.782 and 0.770，respectively（all P < 0.05），and their optimal cut⁃off values were 1.00 and 4.74，respectively. The traditional nCD64 index only had good diagnostic efficacy in AID patients（AUC = 0.887， P < 0.05）. The modified index had preferable diagnostic efficacy in all three diseases（all AUCs > 0.75，P < 0.05）. Conclusion Both modified nCD64 index and the traditional nCD64 index have potential diagnostic efficacy in the differential diagnosis of infection，and their diagnostic values are best in AID. The modified nCD64 index is more valuable in auxiliary diagnosing infection in patients with fever symptom from emergency department or patients with hematological malignancies than the traditional nCD64 index. 

Key words:

infection, neutrophils CD64 index, autoimmune diseases, hematologic tumors