Which additive in the Canary Yellow Tube is used for blood cultures?

Which additive in the Canary Yellow Tube is used for blood cultures?

• A. ACD
• B. SPS
• C. Na Citrate
• D. EDTA

Answer: (B)

Blood culture tubes need an additive that keeps blood from clotting while preserving any bacteria that may be present so they can grow in culture. The Canary Yellow Tube uses Sodium Polyanethol Sulfonate for this purpose. SPS acts as an anticoagulant and helps protect microbes by dampening components of the blood that would kill or inhibit them, and it can also counteract some antibiotic effects, improving the chances of detecting pathogens. Other additives serve different tests: ACD is for preserving blood components for transfusion-related studies, sodium citrate and EDTA are chelating agents used to prevent clotting in coagulation tests or to preserve cells, not to support culture growth.

Blood culture tubes need an additive that keeps blood from clotting while preserving any bacteria that may be present so they can grow in culture. The Canary Yellow Tube uses Sodium Polyanethol Sulfonate for this purpose. SPS acts as an anticoagulant and helps protect microbes by dampening components of the blood that would kill or inhibit them, and it can also counteract some antibiotic effects, improving the chances of detecting pathogens. Other additives serve different tests: ACD is for preserving blood components for transfusion-related studies, sodium citrate and EDTA are chelating agents used to prevent clotting in coagulation tests or to preserve cells, not to support culture growth.