Thrombasthenia, also known as Glanzmann's disease, is the most common type of inherited bleeding disorder caused by platelet function defects. It is currently known that this disease is due to a deficiency in platelet membrane glycoproteins (GP) IIb/IIIa, and is further classified into three types: Type I (GP IIb/IIIa less than 5% of normal), Type II (GP IIb/IIIa between 5-25% of normal), and the variant type (GP IIb/IIIa at 40-100% of normal but with structural abnormalities). Molecular biology techniques have identified various GP IIIa or GP IIa gene defects. In 10-50% of cases, the parents are consanguineous, following an autosomal recessive inheritance pattern. Heterozygotes do not exhibit significant hemorrhagic symptoms.

bubble_chart Clinical Manifestations

1. Consistent with autosomal recessive inheritance.
2. Bleeding symptoms have been present since childhood, manifested as grade II or grade III skin and mucosal bleeding, such as ecchymosis, epistaxis, gingival bleeding, etc. Joint bleeding or deep tissue/organ hematomas generally do not occur. Adolescent girls may experience hypermenorrhea, especially excessive bleeding during menarche, which can be a common initial bleeding symptom. Prolonged bleeding may occur after trauma or surgery.

bubble_chart Auxiliary Examination

1. The platelet count is normal, and the blood smear shows scattered distribution of platelets without clumping. 2. Prolonged bleeding time. 3. Poor or normal clot retraction. 4. Abnormal platelet function tests. (1) Aggregation tests: (i) No aggregation is induced by ADP, epinephrine, collagen, thrombin, or arachidonic acid. In a few cases, aggregation may occur with collagen, arachidonic acid, or thrombin. (ii) Ristocetin-induced aggregation is normal or reduced. 5. Decreased or qualitatively abnormal platelet membrane glycoproteins (GP) IIb/IIIa (CD41/CD61).

﹝Treatment﹞

(1) Avoid trauma and refrain from using drugs that inhibit platelet function, such as aspirin, dipyridamole, non-steroidal anti-inflammatory drugs, barbiturates, antihistamines, atropine, dextran, chlorpromazine, prostaglandins, etc. (2) For active bleeding, apply local pressure to stop the bleeding. Topical hemostatic agents such as hemostatic powder, Yunnan Baiyao, gelatin sponge, and thrombin can be used. (3) Transfusion of fresh whole blood, fresh plasma, platelet-rich fresh plasma, or concentrated platelet suspension can help control bleeding. (4) A trial of 50% MgSO4, 3–5 ml orally three times daily, may be considered.

bubble_chart Differentiation

Children presenting with bleeding symptoms since childhood, affecting both genders, with normal platelet and coagulation tests but prolonged bleeding time should be considered for possible platelet function disorders. Such bleeding disorders, apart from Glanzmann's thrombasthenia, include Bernard-Soulier syndrome, storage pool disease, among others, primarily requiring laboratory tests for differentiation.