Which color pair indicates EDTA tubes used for hematology analysis?

• A. Red
• B. Light Blue
• C. Lavender and Pink
• D. Green

Answer: (C)

EDTA tubes used for hematology analysis are identified by tubes that contain EDTA as the anticoagulant, which preserves blood cell morphology and prevents clotting. The lavender-top tube is the classic hematology tube, filled with EDTA to keep cells intact for CBCs and other cell-based tests. Pink-top tubes also contain EDTA (often K2EDTA) and are used for EDTA-related testing in some hematology and blood-bank applications. The key is the EDTA anticoagulant, which is different from other common additives: red tops have no additive or are serum tubes, light blue tops use sodium citrate for coagulation testing, and green tops use heparin. So, the lavender and pink color pair signals EDTA tubes appropriate for hematology analysis.