Bacteremia, Blood Culture Contamination, Contamination
Conditions
Keywords
Procalcitonin
Brief summary
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.
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.
Interventions
DIAGNOSTIC_TESTProcalcitonin dosage
Plasma PCT levels measured by automated enzyme immunoassay (Kryptor).
Sponsors
Central Hospital, Nancy, France
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| To evaluate the diagnostic potential of plasma procalcitonin in detecting blood culture contamination | 24 hours | 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). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 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 | 24 hours | 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 |
Countries
France
Outcome results
None listed