A Case of EDTA Dependent Platelet Phagocytosis by Neutrophils in Mycosis Fungoides / 대한임상병리학회지

ABSTRACT

In vitro ethylene-diamine-tetra-acetic acid (EDTA) dependent satellitism and phagocytosis of platelets by neutrophils have been considered to be rare phenomena. It is associated with pseudothrombocytopenia, abnormal histogram of platelets and pseudoleukocytosis on complete blood cell count (CBC) by automated blood cell counter, but these findings are not found in heparinized or sodium citrated blood. It has no clinical significance such as bleeding tendency or abnormal platelet function. EDTA dependent platelet satellitosis and phagocytosis must be differentiated from true thrombocytopenia. We report a case of EDTA dependent platelet phagocytosis by neutrophils in a 68 year-old male patient who was diagnosed as mycosis fungoides. His EDTA blood smear showed frequent phagocytosis of platelets by neutrophils and occasional platelet satellitism. The bood cell counts were within normal limits without pseudothrombocytopenia. Phagocytized platelets were confirmed by immunohistochemistry using GpIIb/IIIa antibody and transmission electron micrographs.