Confirmation of CLABSI requires both a positive blood culture and a collaborative clinical and microbiological review of the patient.
Blood culture should be obtained prior to initiation of antibiotic therapy. Paired blood samples, drawn from the catheter and a peripheral vein, should be sent for culture, and the bottles should be appropriately marked to reflect the site from which the samples were obtained. If a blood sample cannot be drawn from a peripheral vein, it is recommended that 2 blood samples should be drawn through different catheter lumens.
The case definition for BSI (must meet one of two criteria):
- Patient has a recognized pathogen cultured from one or more blood cultures AND
- Organism cultured from blood is not related to an infection at another site
Criterion 1:
- Patient has at least one of the following signs or symptoms: fever (>38°C) or hypotension AND
- Organism cultured from blood is not related to an infection at another site
- Common skin contaminant is cultured from two or more blood cultures drawn on separate occasions
Criterion 2:
Establishing diagnosis of CRBSI requires the presence of BSI and demonstrating that the infection is related to the catheter. The catheter tip should be cultured and growth of >15 colony-forming units (CFU) from a 5-cm segment tip by semiquantitative (roll-plate) culture, or growth of > 102cfu by quantitative (sonication) broth culture of the same pathogen as in peripheral blood culture supports the diagnosis of CRBSI.