A-28
Appendices: Color Plates
e. Cells with large dark purple granules Figure 5
are basophils (Figure 5). Normal = Basophils
<1-2% of the total white cell count.
- The size and shape of red cells should
be noted. A normal red cell is about the size
of the nucleus of a normal lymphocyte (see
above Figure 2.), and extreme variations
towards larger (macrocytes), smaller Figure 6
(microcytes), or variations between the size Sickle cells and
of individual red cells (anisocytosis) should target cells.
be noted. Poikilocytosis refers to significant
differences in the shape (normally a bi-concave
disc) of individual red cells. Sickle cells have
abnormal hemoglobin, which distorts the cell
when deoxygenated.
Cells in which the normally pale central area
has a collection of hemoglobin surrounded by
a pale rim are called Target Cells (Figure 6).
Normal red cell counts are between 4-6
million/cubic microliter.
c. Platelets (Figure 7),
cellular fragments (often with distinct Figure 7
granules) much smaller than the red or Normal red
white cells, should be noted. On high cells with
power oil immersion (1000X) each normal platelets
platelet in a field represents a peripheral (the small
count of 20,000/cubic microliter. The purple cells are
platelets in several fields should be platelets-there
counted and averaged to get an idea of are 5)
the peripheral count. Normal platelet
numbers are between 150,000 to
450,000/cubic microliter.
All pictures taken with permission from Hoffbrand AV, and Pettit JE. Clinical Hematology. Gower Medical
Publishing, London and New York. 1988
What Not To Do: Do not break slide or microscope. Do not confuse the different types of WBCs.