Diagnostic Performance of Plasma Procalcitonin for the Detection of Blood Cultures Contaminations

Diagnostic Performance of Plasma Procalcitonin in Screening for Contamination When Detecting Potential Contaminants in Blood Cultures

In blood cultures, species considered as potentially contaminating (coagulase negative staphylococci (CNS), Bacillus spp., Corynebacterium spp., Cutibacterium acnes, Micrococcus spp., viridans group streptococci, and Clostridium perfringens) can, however, be responsable for true bacteremia.

Blood levels of the prohormone procalcitonin (PCT) markedly increase in the early stages of bacterial infections. The aim of our study is to determine the role of plasma PCT as a biomarker differentiating blood culture contaminations from true bacteremia.

Study Overview

• Status: Completed
• Conditions: Bacteremia; Contamination; Blood Culture Contamination
• Intervention / Treatment: Diagnostic test: Procalcitonin dosage

Detailed Description

Blood culture contamination is defined by the introduction into of a microorganism into blood culture bottles from either the patient's or healthcare worker's flora, or the immediate environment during specimen collection. Species considered as potentially contaminating (coagulase negative staphylococci (CNS), Bacillus spp., Corynebacterium spp., Cutibacterium acnes, Micrococcus spp., viridans group streptococci, and Clostridium perfringens) can, however, be responsible for true bacteremia. If an organism belonging to one of those species is detected in isolates, rapidly and accurately assessing its contaminant or infectious potential is hence important to ensure effective antibiotic therapy as well as to reduce financial burden caused by unnecessary treatments, and additional clinical and laboratory costs.

Blood levels of the prohormone procalcitonin (PCT) markedly increase in the early stages of bacterial infections. The aim of our study is to determine the role of plasma PCT as a biomarker differentiating blood culture contaminations from true bacteremia.

• Study Type: Observational
• Enrollment (Actual): 147

Contacts and Locations

Study Locations

• France
  • Nancy, France, 54500
    • CHRU of Nancy

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients hospitalized at the Nancy CHRU and at the Lorraine Cancer Institute (ICL) from January 2016 to May 2019 Patients screened for positive blood culture to one of the following microorganisms: coagulase negative staphylococci, viridans group streptococci; as well as procalcitonin levels measured at 24 hours.

Description

Inclusion Criteria:

• At least one blood culture positive for of the following microorganisms: coagulase negative staphylococci, viridans group streptococci
• PCT levels measurement on the day of blood culture specimen collection
• Adult patients

Exclusion Criteria:

• Patients with less than 3 blood culture bottles collected

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Positives blood cultures; Collection of clinical and biological data of patients with blood cultures positives for potential contaminants, as well as PCT levels measurements, from January 2016 to May 2019 at the Nancy CHRU	Diagnostic test: Procalcitonin dosage; Plasma PCT levels measured by automated enzyme immunoassay (Kryptor).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To evaluate the diagnostic potential of plasma procalcitonin in detecting blood culture contamination	True contamination will be considered if all of the following biological criteria are met: Only one bottle collected is positive; The growth time in the first positive bottle is more than 20 hours Plasma proclacitonin levels measured by automated enzyme immunoassay (Kryptor).	24 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To compare plasma PCT levels in patients with true bacteremia, probable bacteremia and contamination caused by the presence of bacterial species with high contaminant potential	Bacteremia will be considered as present (" true bacteremia ") if all of the following biological criteria are met: The same microorganism (amongst CNS, viridans group streptococci) is isolated in 100% of blood culture bottles collected from a given patient; The growth time in the first positive bottle is less than or equal to 16 hours Probable bacteremia: When biological criteria of bacteremia and contamination are not fulled; When a antibiotic therapy is administrated without focal infection identified by cliniciens	24 hours

Collaborators and Investigators

• Sponsor: Central Hospital, Nancy, France

Publications and helpful links

General Publications

• Schuetz P, Albrich W, Mueller B. Procalcitonin for diagnosis of infection and guide to antibiotic decisions: past, present and future. BMC Med. 2011 Sep 22;9:107. doi: 10.1186/1741-7015-9-107.
• Lu B, Shi L, Zhu F, Zhao H. Clinical Utility of the Time-to-Positivity/Procalcitonin Ratio to Predict Bloodstream Infection Due to Coagulase-Negative Staphylococci. Lab Med. 1 nov 2013;44(4):313-8.
• Schuetz P, Mueller B, Trampuz A. Serum procalcitonin for discrimination of blood contamination from bloodstream infection due to coagulase-negative staphylococci. Infection. 2007 Oct;35(5):352-5. doi: 10.1007/s15010-007-7065-0. Epub 2007 Sep 19.
• Berthezene C, Aissa N, Manteaux AE, Gueant JL, Oussalah A, Lozniewski A. Accuracy of procalcitonin for diagnosing peripheral blood culture contamination among patients with positive blood culture for potential contaminants. Infection. 2021 Dec;49(6):1249-1255. doi: 10.1007/s15010-021-01697-4. Epub 2021 Sep 15.

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2020
• Primary Completion (Actual): July 31, 2020
• Study Completion (Actual): September 5, 2020

Study Registration Dates

• First Submitted: September 28, 2020
• First Submitted That Met QC Criteria: October 1, 2020
• First Posted (Actual): October 5, 2020

Study Record Updates

• Last Update Posted (Actual): October 5, 2020
• Last Update Submitted That Met QC Criteria: October 1, 2020
• Last Verified: September 1, 2020

More Information

Terms related to this study

• Keywords: Procalcitonin
• Additional Relevant MeSH Terms: Pathologic Processes; Infections; Systemic Inflammatory Response Syndrome; Inflammation; Bacterial Infections; Bacterial Infections and Mycoses; Sepsis; Bacteremia
• Other Study ID Numbers: 2020PI140

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No