title: Procalcitonin levels in gram-positive, gram-negative, and fungal bloodstream infections.
abstract: Procalcitonin (PCT) can discriminate bacterial from viral systemic infections and true bacteremia from contaminated blood cultures. The aim of this study was to evaluate PCT diagnostic accuracy in discriminating Gram-positive, Gram-negative, and fungal bloodstream infections. A total of 1,949 samples from patients with suspected bloodstream infections were included in the study. Median PCT value in Gram-negative (13.8 ng/mL, interquartile range (IQR) 3.4-44.1) bacteremias was significantly higher than in Gram-positive (2.1 ng/mL, IQR 0.6-7.6) or fungal (0.5 ng/mL, IQR 0.4-1) infections (P < 0.0001). Receiver operating characteristic analysis showed an area under the curve (AUC) for PCT of 0.765 (95% CI 0.725-0.805, P < 0.0001) in discriminating Gram-negatives from Gram-positives at the best cut-off value of 10.8 ng/mL and an AUC of 0.944 (95% CI 0.919-0.969, P < 0.0001) in discriminating Gram-negatives from fungi at the best cut-off of 1.6 ng/mL. Additional results showed a significant difference in median PCT values between Enterobacteriaceae and nonfermentative Gram-negative bacteria (17.1 ng/mL, IQR 5.9-48.5 versus 3.5 ng/mL, IQR 0.8-21.5; P < 0.0001). This study suggests that PCT may be of value to distinguish Gram-negative from Gram-positive and fungal bloodstream infections. Nevertheless, its utility to predict different microorganisms needs to be assessed in further studies.
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Christian
authors: 0000-0002-8689-7028
authors: C
authors: Leli
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Marta
authors: M
authors: Ferranti
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Amedeo
authors: A
authors: Moretti
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Zainab Salim
authors: ZS
authors: Al Dhahab
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Elio
authors: E
authors: Cenci
authors: Microbiology Section, Department of Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
authors: Antonella
authors: A
authors: Mencacci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000097:blood*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D005260:Female; D006090:Gram-Negative Bacteria; D006094:Gram-Positive Bacteria; D006801:Humans; D008297:Male; D008875:Middle Aged; D009181:Mycoses / Q000097:blood*; D011498:Protein Precursors / Q000097:blood*
chemical_list: C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide