Abstract
Background: to assess the distribution of bacteremia pathogens
in elderly patients, to evaluate the impact of gender on pathogen
distribution, and to determine the predictive value of routine blood
parameters for diagnosing bacteremia.
Methods: A total of 151 elderly patients (≥60 years old) who
admitted to hospital from October 2022 to June 2023 were retrospectively
studied. Routine blood test and blood culture were performed. ROC curve
was used to analyze the diagnostic efficacy of blood routine parameters:
white blood cell (WBC), neutrophil-to-lymphocyte ratio (NLR),
platelet-lymphocyte ratio (PLR), red blood cell distribution width
(RDW).
Results: The subjects were categorized into either the
culture-positive group (82 cases) and the culture-negative one (69
cases) according to blood culture results. There were no significant
differences in age and gender between groups. The primary bacterial
pathogens of bacteremia in the elderly were Escherichia coli,
Klebsiella pneumoniae and Streptococcus. A significantly higher
culture positivity rate for E. coli was found in elderly female
patients compared to their male counterparts (P = 0.021). The
area under the ROC curve of four parameters was: WBC, 0.851 (95%
confidence interval (CI) 0.790 - 0.912); NLR, 0.919 (95% CI 0.875 -
0.963); PLR, 0.609 (95% CI 0.518 - 0.700); and RDW was 0.626 (95% CI
0.563 - 0.717).
Conclusion : The most frequently pathogenic microorganism
causing bacteremia was E. coli , with elderly female patients
having a significantly higher rate of culture positivity. Routine blood
parameters (WBC, NLR, PLR, and RDW) demonstrated predictive potential
for bacteremia in elderly patients.