Which tube type is commonly used for CBC testing due to its additive?

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Multiple Choice

Which tube type is commonly used for CBC testing due to its additive?

For CBC testing you need blood that remains unclotted so cell counts and morphology can be measured accurately. The lavender-topped tube uses EDTA as an anticoagulant, which binds calcium to stop the clotting process and preserves the cells' shape and integrity. This makes it ideal for counting white and red blood cells and platelets with reliable results in an automated analyzer. Other tube types either lack an anticoagulant entirely (risking clotting) or use different additives not suited for CBCs—green tops use heparin, gray tops use fluoride/oxalate for glucose testing, and red tops are plain. That combination of effective anticoagulation and cell preservation is why the lavender-top tube is commonly used for CBC.

For CBC testing you need blood that remains unclotted so cell counts and morphology can be measured accurately. The lavender-topped tube uses EDTA as an anticoagulant, which binds calcium to stop the clotting process and preserves the cells' shape and integrity. This makes it ideal for counting white and red blood cells and platelets with reliable results in an automated analyzer. Other tube types either lack an anticoagulant entirely (risking clotting) or use different additives not suited for CBCs—green tops use heparin, gray tops use fluoride/oxalate for glucose testing, and red tops are plain. That combination of effective anticoagulation and cell preservation is why the lavender-top tube is commonly used for CBC.

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