What type of tube is used to collect specimens for a white blood count?

The EDTA tube is specifically used for collecting specimens for a white blood count because it contains ethylenediaminetetraacetic acid (EDTA), an anticoagulant that effectively binds calcium ions in the blood. By preventing clotting, EDTA allows for accurate counting and analysis of the white blood cells (WBCs) in the sample.

When blood is drawn into an EDTA tube, it remains in a liquid state, allowing laboratory technicians to perform a complete blood count (CBC) and assess the number and types of white blood cells present. This is crucial for diagnosing various conditions, including infections, and for evaluating immune function.

In contrast, a sodium citrate tube is typically used for coagulation studies, while a heparin tube is often employed for biochemical testing. A glass tube can be used for serum collection but does not prevent clotting in the same manner as EDTA, making it unsuitable for WBC enumeration. Thus, utilizing the appropriate tube type is essential for obtaining viable and accurate lab results.