Sickle cells (drepanocytes)

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

Slide 103 [100X]  

Slide 103 is from a 20 year old male with sickle cell anemia. The sharply pointed cells reflect irreversible sickling.  (RBC 2.20 x 1012 / L; hemoglobin 7.5 G / dL; and hematocrit 21.3%). Most laboratories correctly identified the arrowed cells as sickle cells (drepanocyte, code: 41). Twenty nine laboratories identified the cells as schistocytes (code: 39). The helmet cell form of schistocytes can appear similar to a sickle cell, also having pointed ends, but -unlike a sickle cell - does not usually elongate beyond the circumference of a normal sized red blood cell. The central diameter of a sickle cell is usually narrower than that of a schistocyte. See (O’Connor, B H,: A Color Atlas and Instruction Manual of Peripheral Blood Cell Morphology, Williams and Wilkins, 1984). Note the folded red blood cell in the upper right hand corner. Target cells, polychromatophilic red cells, a Howell-Jolly body, and burr cells are evident on the smear.

Number of Responses

% of Laboratories

Cell Code and Type

427

93.0

Code: 41    Sickle cell (drepanocyte)

29

6.3

Code:  39    Schistocyte

1

0.2

Code:  18    Hypersegmentation

1

0.2

Code:  34    Elliptocyte

1

0.2

Code:  45    Tear drop cell (dacrocyte)

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