Related tests: Platelet count, PT, PTT

Clinical significanceClinical indicationsSample typePreparationNotes

Clinical significance
Antiplatelet antibodies may be alloimmune or autoimmune in origin. In the first case they may be found in neonatal thrombocytopenia, with antibodies mainly directed against the platelet surface antigen HPA-1a, or in post-transfusion forms, with antibodies mainly directed against HLA class I. In autoimmune forms, particularly idiopathic thrombocytopenic purpura (ITP), antibodies against platelet glycoprotein antigens GPIIb/IIIa and, more rarely, GPIb/IX may be detected.

Clinical indications
Immune thrombocytopenias.

Sample type
The patient must have a blood sample taken.

Preparation
You must fast for at least 8 hours; a small amount of water is allowed. You must have been standing or sitting upright for at least 30 minutes.

Notes
Antiplatelet antibodies may nevertheless be present in patients with non-immune thrombocytopenia.