Distinguishing Gram-positive and Gram-negative bloodstream infections through leukocytes, C-reactive protein, procalcitonin, and D-Dimer: an empirical antibiotic guidance.

Abstract

This retrospective study aimed to compare the difference of the levels of white blood cells (WBC), C-reactive protein (CRP), procalcitonin, and D-Dimer in the bloodstream infection (BSI) patients, and their values in distinguishing bacterial categories. A total of 847 BSI patients were analysed and divided into Gram-positive BSI (GP-BSI) and Gram-negative BSI (GN-BSI) groups. Most frequently isolated pathogens in GP-BSI were Staphylococcus epidermidis (35.75%), followed by Staphylococcus hominis (18.33%), and Streptococcus haemolyticus (10.16%), while in GN-BSI, Escherichia coli (30.07%), Klebsiella pneumoniae (23.98%), and Acinetobacter baumannii (13.18%) were the most common. The predictive value was evaluated based on 3 years of patient data, which showed an area under the curve (AUC) of 0.828. It was further validated using 2 years of data, which yielded an AUC of 0.925. Significant differences existed in the procalcitonin, D-Dimer, and CRP levels between GN-BSI and GP-BSI. The current results provide a more effective strategy for early differential diagnosis in bacterial categorization of BSI when combining WBC, CRP, procalcitonin, and D-Dimer measurements.