New York State Department of Health - Wadsworth Center - Cytohematology Proficiency Testing
Slide 160 [100X]        Click here for a higher resolution image.
Rouleaux (Code 38) formation of red blood cells is evident in this case of multiple myeloma. The increased amounts of plasma proteins cause the red blood cells to become coated and “sticky” lending themselves to the stacking appearance. Due to the abundance of cells present in a thick area of a slide, red blood cells can appear as if they display a “stack” appearance; this however is not true rouleaux. Rouleaux formation is considered pathological only when this formation occurs in the thin area of the blood smear and when four or more red blood cells are involved.

Number of Responses

Percent of Laboratories

Cell Code and Type

419

99.5%

Code 38:  Rouleaux

1

0.2%

Code 55:  Yeast-Fungi

1

0.2%

Code 30:  Acanthocyte

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