Shiyan Zhang

and 6 more

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.