Reading and Reporting Direct Smears

Size and Appearance of Cellular Elements

Type of Cell Size Shape Stain
Epithelial cells 25 microns irregular pink/red
White blood cells 12 microns round pink/red
Red blood cells 7 microns round pink/red
Yeast 7 microns ovoid blue
Bacteria 0.5 - 1 micron variable blue or red
  • Epithelial cells are larger than white blood cells and red blood cells, and contain a single nucleus.
  • White blood cells (neutrophils contained in pus) usually show a segmented nucleus.
  • Red blood cells are 1/2 to 2/3 as large as white blood cells, contain no nucleus, and are Gram negative.
  • Hyphae are gram positive tubular filamentous fungal elements which may show branching or intertwining.
  • Yeast cells are round to oval, often budding, Gram positive fungal elements, about the same size as RBCs. They are generally much larger than bacteria.




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