What is Glanzmann's Thrombasthenia?

Glanzmann's Thrombasthenia is a platelet disorder. It is extremely rare, hereditary (autosomal recessive), it affects both men and women, and can be quite severe. The condition is named after the Swiss pediatrician Eduard Glanzmann (1887-1959) who first described it in 1918. Other names for Glanzmann's thrombasthenia are: Glanzmann Disease, Platelet Glycoprotein IIb/IIIa Deficiency, and Platelet Fibrinogen Receptor Deficiency.

2) What are the characteristics of Glanzmann's Thrombasthenia?

The four main characteristics of Glanzmann's thrombasthenia are: a) hemorrhagic diathesis (i.e. bleeding tendency, prolonged bleeding time), b) abnormal platelet aggregation, c) normal platelet count and size, and d) normal prothrombin time (PT) and activated partial thromboplastin time (aPTT).

3) What are platelets?

Platelets (a.k.a. thrombocytes) are tiny cellular blood components that help blood to clot. What is more, platelets are the body's first line of defense against bleeding (primary hemostasis). Whenever we sustain a cut, however small, platelets rush to the site of injury, clump together (platelet aggregation), attach themselves to the exposed subendothelium (platelet adhesion), and form a clot, a scab (formation of the platelet hemostatic plug).

4) What is thrombasthenia?

The term thrombasthenia derives from the Greek words thrombos (thrombus, clot) and astheneia (weakness, disease). Literally, the word means "weak platelets". In Glanzmann's thrombasthenia, platelets fail to aggregate (clump together) to form a normal clot.

5) So... what causes the bleeding tendency in Glanzmann's Thrombasthenia?

There is a special glycoprotein complex (GPIIb/IIIa) on the platelet membrane. This complex is essential to normal blood coagulation: It acts as a receptor for von Willebrand Factor (vWF) and fibrinogen, two key players in blood clotting. When the complex GPIIb/IIIa is absent, deficient, or dysfunctional, as in Glanzmann's thrombasthenia, primary hemostasis cannot take place and the patient is susceptible to bleeding.

6) What are the symptoms of Glanzmann's Thrombasthenia?

Symptoms are essentially the same as with any platelet disorder, whether quantitative or qualitative: spontaneous bleeding from the nose (epistaxis) and gums (gingival hemorrhage), blood in the urine (hematuria), unusually heavy menstruation (menorrhagia), abnormal bruising, and petechiae (tiny little reddish marks on the skin, resembling a rash).

7) How is Glanzmann's Thrombasthenia diagnosed?

Laboratory tests that can diagnose Glanzmann's thrombasthenia include complete blood count (CBC) and peripheral smear, coagulation tests (bleeding time, prothrombin time, and activated partial thromboplastin time), as well as special tests that study GPIIb/IIIa and platelet aggregation.

8) How is Glanzmann's Thrombasthenia treated?

Glanzmann's thrombasthenia is a lifelong condition. There is no cure for Glanzmann's thrombasthenia. Treatment is symptomatic, i.e. it is basically provided to control the bleeding and the side-effects of chronic bleeding (e.g. iron supplementation for iron deficiency anemia). Platelet transfusions are given in case of severe bleeding, or as a prophylactic measure before major surgery and dental procedures, prior to delivery and postpartum. The most important aspect of management is prevention: For example, patients with Glanzmann's thrombasthenia should avoid anti-platelet drugs (e.g. aspirin). Patient education and trauma prevention ensure a good prognosis for people with Glanzmann's thrombasthenia.