Glanzmann Thrombasthenia

Key Features

• Results from a qualitative or quantitative abnormality in the platelet glycoprotein IIb/IIIa receptor on the platelet membrane and the fibrinogen receptor critical for linking platelets during initial platelet aggregation/platelet plug formation

• Inheritance is autosomal recessive

Clinical Findings

• Onset of bleeding is usually in infancy or childhood, but some forms are milder and present later in life

• Degree of deficiency in IIb/IIIa may not correlate well with bleeding symptoms

• Bleeding due to defective platelets is classically mucocutaneous, but is not limited to mucocutaneous surfaces

• Bleeding

  • Mucosal (epistaxis, gingival)

  • Menorrhagia

  • Postoperative

  • Variable severity but may be severe

Diagnosis

• Platelet aggregation studies show marked impairment of aggregation in response to stimulation with various agonists

Treatment

• Platelet transfusions when necessary

• Desmopressin acetate (DDAVP), antifibrinolytic agents, and recombinant human activated factor VII also have been used successfully