The effect of anticoagulant on the cell size of hairy cells and other malignant hematologic cells. A study with the Hemalog D.

The size of blood cells can be influenced by anticoagulants, especially the EDTA derivatives. The Hemalog D differential counter was used in the diagnosis and follow-up of hairy cell leukemia. The percentage of large unstained cells (LUC) closely correlated with the percentage of hairy cells. However, there was a highly reproducible rapid decrease in LUC during the period of time after collection of the blood, when potassium EDTA was used as an anticoagulant. This "loss" in LUC could not be attributed to a selective disappearance of hairy cells, but to a shift into the lymphocyte box. The steep decline did not occur when sodium EDTA was used. The phenomenon seems to be specific for hairy cells, as it was not observed, or was considerably less obvious in other lymphocytic and non-lymphocytic leukemic malignancies.