HoG Handbook

Testing for Glanzmann’s Thrombasthenia


blood testLaboratory tests are necessary to diagnose GT.

In people with GT, the platelet count is normal.  The platelets have a normal size and shape when viewed under a microscope.

A person with GT will usually have a long bleeding time.  Their results with the PFA 100® will also be abnormal.
An important test for GT is for platelet aggregation.  When the different chemicals (agonists) are mixed with the patient’s platelets, only the antibiotic ristocetin makes them clump together.

Blood tests are available to check for deficiency of GPIIb/IIIa in the platelets.