Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Sep 14;9(10):ofac467.
doi: 10.1093/ofid/ofac467. eCollection 2022 Oct.

Early Biomarker-Guided Prediction of Bloodstream Infection in Critically Ill Patients: C-Reactive Protein, Procalcitonin, and Leukocytes

Frederik Boetius Hertz  1   2 , Magnus G Ahlström  3 , Morten H Bestle  4   5 , Lars Hein  4 , Thomas Mohr  6 , Jens D Lundgren  7 , Tina Galle  8 , Mads Holmen Andersen  9 , Daniel Murray  7 , Anne Lindhardt  10 , Theis Skovsgaard Itenov  11   4 , Jens Ulrik Staehr Jensen  7   11   5
Affiliations

Early Biomarker-Guided Prediction of Bloodstream Infection in Critically Ill Patients: C-Reactive Protein, Procalcitonin, and Leukocytes

Frederik Boetius Hertz et al. Open Forum Infect Dis. .

Abstract

Background: Bloodstream infections (BSIs) often lead to critical illness and death. The primary aim of this study was to determine the diagnostic accuracy of the biomarkers C-reactive protein (CRP), procalcitonin (PCT), and leukocyte count for the diagnosis of BSI in critically ill patients.

Methods: This was a nested case-control study based on the Procalcitonin And Survival Study (PASS) trial (n = 1200). Patients who were admitted to the intensive care unit (ICU) <24 hours, and not expected to die within <24 hours, were recruited. For the current study, we included patients with a BSI within ±3 days of ICU admission and matched controls without a BSI in a 1:2 ratio. Diagnostic accuracy for BSI for the biomarkers on days 1, 2, and 3 of ICU admission was assessed. Sensitivity, specificity, and negative and positive predictive values were calculated for prespecified thresholds and for a data-driven cutoff.

Results: In total, there were 525 patients (n = 175 cases, 350 controls). The fixed low threshold for all 3 biomarkers (CRP = 20 mg/L; leucocytes = 10 × 109/L; PCT = 0.4 ng/mL) resulted in negative predictive values on day 1: CRP = 0.91; 95% CI, 0.75-1.00; leukocyte = 0.75; 95% CI, 0.68-0.81; PCT = 0.91; 95% CI, 0.84-0.96). Combining the 3 biomarkers yielded similar results as PCT alone (P = .5).

Conclusions: CRP and PCT could in most cases rule out BSI in critically ill patients. As almost no patients had low CRP and ∼20% had low PCT, a low PCT could be used, along with other information, to guide clinical decisions.

Keywords: BSI; CRP; PCT; bloodstream infection; leukocyte.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
A–C, The figures show ROC curves for the predictive value of three biomarkers on the risk of blood stream infection on day 1–3. Abbreviations: CRP, C-reactive protein; ROC, receiver operating characteristics.
Figure 2.
Figure 2.
A–C, The figures show ROC curves for the predictive value of combined inflammatory markers PCT, CRP, and leukocyte counts for the risk of bloodstream infection on days 1–3. Abbreviations: CRP, C-reactive protein; PCT, procalcitonin; ROC, receiver operating characteristics.
See this image and copyright information in PMC

References

    1. Kontula KSK, Skogberg K, Ollgren J, Järvinen A, Lyytikäinen O. Early deaths in bloodstream infections: a population-based case series. Infect Dis (Auckl) 2016; 48:379–85. - PubMed
    1. Papadimitriou-Olivgeris M, Perdikis K, Cois M, et al. . Predictors for delayed antibiotic administration among bacteraemic patients in the emergency department: differences between medical and surgical interns. Eur J Clin Invest 2020; 50:e13324. - PubMed
    1. Townsend SR. Antibiotic administration and timing: risks, delay, zombies. Crit Care Med 2021; 49:1818–21. - PubMed
    1. Arabestani MR, Rastiany S, Kazemi S, Mousavi SM. Conventional, molecular methods and biomarkers molecules in detection of septicemia. Adv Biomed Res 2015; 4:120. - PMC - PubMed
    1. Sen P, Demirdal T, Nemli SA, et al. . Infection markers as predictors of bacteremia in an intensive care unit: a prospective study. Pak J Med Sci 2018; 34:1517–24. - PMC - PubMed