Which test is most affected by microdots in an EDTA tube drawn for a complete blood count?

Microdots, which can appear in EDTA tubes due to improper mixing or the presence of particulate matter, can significantly interfere with blood counts. Among the different components measured in a complete blood count, the platelet count is particularly sensitive to such issues.

The presence of microdots can lead to clumping or aggregation of platelets, causing an inaccurate representation of the actual platelet count in the sample. When the sample is processed, the analyzer may misidentify these aggregates as a reduction in platelet number, thus yielding a falsely low result. Consequently, this interference is specifically detrimental to the accuracy of the platelet count, highlighting the importance of proper sample handling and tube preparation in laboratory testing.

In contrast, while microdots could potentially affect the other blood parameters to some extent, they are more likely to have a pronounced impact on the platelet count due to the physical nature of how platelets are assessed in automated counting systems. This specificity is why the platelet count is seen as the most affected test when microdots are present in an EDTA tube used for a complete blood count.