Sometimes platelets show few or no granules.
Testing: Romanowsky peripheral blood smear
percent agranular or hypogranular platelets =
= (number of agranular or hypogranular) / (total platelets counted) * 100%
Percent |
Grade |
< 5% |
occasional (+/-) |
5 to 25% |
1+ |
25.1 to 50% |
2+ |
50.1 to 75% |
3+ |
> 75% |
4+ |
Pathologic agranular/hypogranular platelets can be seen with::
(1) myelodysplasia
(2) myeloproliferative disorder
(3) AML
(4) gray platelet syndrome (alpha storage pool disease)
Differentieal diagnosis:
(1) cytoplasmic fragments of leukemia cells (pseudothrombocyte)
(2) in vitro artifact (degranulation)
Specialty: Hematology Oncology, Clinical Laboratory