New York State Department of Health - Wadsworth Center - Cytohematology Proficiency Testing

Slide 057 [100X]

This slide was taken from the peripheral blood of a 27 year-old male with thalassemia major. The cell indicated by the arrows is a giant platelet. Compared with the other platelets scattered throughout the picture, and compared to the size of the adjacent red blood cell, the platelet is 1/2 to 2/3 the size of the red blood cells and is a giant platelet. A normal red cell is 6-8 µm in diameter. Normal platelets are approximately 1-4 µm, large platelets are approximately 4-6.5 µm.  Any platelet larger than 6.5 µm may be classified as a giant platelet.Credit was given for both giant platelet and platelet.

NUMBER OF RESPONSES	% OF LABORATORIES	CELL CODE AND TYPE
472	97.9%	Code:52 Giant platelet
9	1.9%	Code:51 Platelet
1	0.2%	Code:10 Normal lymphocyte

Return to September 1996 Proficiency Test Event