Journal of Applied Hematology

: 2022  |  Volume : 13  |  Issue : 2  |  Page : 110-

Unexpected finding of endothelial cells in peripheral blood smear

Qasem Ibrahim Alneami 
 Department of laboratory and blood bank, King Fahad Central Hospital, Jazan, Saudi Arabia

Correspondence Address:
Dr. Qasem Ibrahim Alneami
King Fahad Central Hospital, Jazan
Saudi Arabia

How to cite this article:
Alneami QI. Unexpected finding of endothelial cells in peripheral blood smear.J Appl Hematol 2022;13:110-110

How to cite this URL:
Alneami QI. Unexpected finding of endothelial cells in peripheral blood smear. J Appl Hematol [serial online] 2022 [cited 2022 Sep 29 ];13:110-110
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Full Text

The peripheral blood smear is one of the best and valuable means of investigation in laboratory hematology.[1]

There are several indications for requesting a peripheral film by the physician that helps in establish a reliable and definitive diagnosis or include or exclude one of the differential diagnoses, depending on the patient's clinical data and correlation with other ancillary study findings.[2]

The following microscopic pictures were taken from a peripheral blood film of a patient presented with erythrocytosis. The morphology of peripheral blood smear was unremarkable; however, at the tail of the blood smear, there is a cluster of cells [Figure 1]a and [Figure 1]b, which are medium to large in size with a round-to-oval nuclei, some they display nuclear grooving, and they do have a moderate to a large amount of pale-blue cytoplasm.{Figure 1}

Endothelial cells are normal inner lining layers of the blood vessels unexpectedly seen in peripheral blood films and rarely shed due to the sharp cutting-edge needles used for venepuncture.[3],[4]

Expanded number of endothelial cells can be seen in a wide variety of conditions that are associated with either vascular damage or accelerated new blood vessel formation ranging from benign and reactive events to malignant diseases.[5]

Due to the rarity of this finding and clustering of these cells, it might be confused with circulating malignant cells, especially in cases where the history and clinical findings are suspicious to be malignant. Moreover, EPO can stimulate new blood vessel formation by expression and upregulation of vascular endothelial growth factor and its receptor, which is a very crucial growth factor for vascular endothelial cells and robust angiogenic factor.[6]

The aforementioned findings might be considered as a new condition associated with an increased number of endothelial cells and hence their presence in the peripheral blood smears.

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