Agranular and Hypogranular Platelets

 

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)