Question

Glanzmann thrombasthenia is due to:

• A. Decreased GpIb
• B. Decreased GpIIb/IIIa
• C. Anti-GpIIb/IIIa antibodies
• D. Inhibition or deficiency of ADAMTS 13

Answer 1

The Correct Option is B

Glanzmann thrombasthenia is a rare genetic platelet disorder characterized by a defect in platelet aggregation, which is essential for blood clotting. This condition is due to a deficiency or dysfunction of the glycoprotein complex GpIIb/IIIa on the surface of platelets.

The typical function of the GpIIb/IIIa complex is to bind fibrinogen and other adhesive proteins, facilitating platelet aggregation at sites of vascular injury. In individuals with Glanzmann thrombasthenia, the decreased availability of functional GpIIb/IIIa impairs this process, leading to increased bleeding tendency.

From the options provided:

Option	Explanation
Decreased GpIb	Not responsible for Glanzmann thrombasthenia; associated with Bernard-Soulier syndrome.
Decreased GpIIb/IIIa	Correct answer; directly causes Glanzmann thrombasthenia.
Anti-GpIIb/IIIa antibodies	Not the cause of Glanzmann thrombasthenia; related to immune-mediated conditions.
Inhibition or deficiency of ADAMTS 13	Related to thrombotic thrombocytopenic purpura, not Glanzmann thrombasthenia.

Thus, the correct answer is Decreased GpIIb/IIIa.