Combined procalcitonin and hemogram parameters contribute to early differential diagnosis of Gram-negative/Gram-positive bloodstream infections.

backgroundHemogram parameters and procalcitonin (PCT) play auxiliary roles in the diagnosis and outcome of sepsis. However, it is not clear whether these indicators can quickly distinguish bacterial classification or guide the choice of empirical antibiotics.

methodsWe retrospectively enrolled 381 patients with bloodstream infections (BSI), divided into Gram-positive bloodstream infections (GP-BSI) and Gram-negative bloodstream infections (GN-BSI). Demographic parameters, hemogram parameters, and PCT were recorded and compared between the two groups.

resultsThe mean platelet volume (MPV), platelet distribution width (PDW), and PCT in the GN-BSI group were significantly higher than those in the GP-BSI group, while the platelet count (PLT), plateletcrit, platelet count-to-white blood cell count ratio (PWR), platelet count-to-neutrophil count ratio (PNR), platelet count-to-PCT ratio (PLT/PCT), and mean platelet volume-to-PCT ratio (MPV/PCT) were significantly lower in the GN-BSI group. Multivariate stepwise logistic regression analysis revealed that the independent predictors of GN-BSI were MPV, PWR, and PCT. The areas under the curve (AUC) for this prediction model was 0.79, with sensitivity =0.75 and specificity =0.71.

conclusionsThere were significant differences in terms of PCT, platelet parameters, and platelet-related index-PCT ratio between GN-BSI and GP-BSI. Combined PCT and hemogram parameters are more conducive to the early differential diagnosis of bacterial classification of BSI.