Background: Elderly patient with community-acquired pneumonia is the leading infectious cause of death. During the clinical diagnosis and
treatment, some elderly patients do not have typical clinical symptoms. Therefore establishment of safe and effective diagnosis, prognostic
assessment systems is important for clinicians.
Objective: To evaluate the diagnostic and prognostic value of the neutrophil CD64 (nCD64) index in elderly patients with community-acquired
Methods: One hundred and twenty-eight elderly patients (≥ 65year) diagnosed with community-acquired pneumonia from December 2018 to
December 2020. All patients were further subdivided into two groups: Non severe community-acquired pneumonia (N-SCAP) group and severe
community-acquired pneumonia (SCAP) group. nCD64 index, procalcitonin (PCT) level, C-reactive protein (CRP) level, White blood cell (WBC)
counts and Neutrophil (NEUT) absolute counts were obtained and CURB-65 scores were calculated for each patient.
Results: The nCD64 index, CRP, PCT, WBC, NEUT levels, CURB-65 score were higher in severe community-acquired pneumonia group patients.
The nCD64 index, CRP, PCT levels, CURB-65 score was higher in non-survivors. The receiver operating characteristic (ROC) curve of nCD64
index was higher than those of CRP, PCT, WBC, NEUT levels for diagnosing infection. The AUC of nCD64 index for predicting 28-day mortality in
community-acquired pneumonia was significantly higher than those of CRP, PCT, WBC and NEUT levels. The AUC of nCD64 index combined with
CURB-65 score was significantly higher than that of CRP, PCT, WBC and NEUT parameter combined with CURB-65 score for predicting 28-day
Conclusion: The neutrophil CD64 index is a valuable biomarker for diagnosis of infection and prognostic evaluation in elderly patients (≥ 65 year)
with community-acquired pneumonia.