MODULE HEMATOLOGYEXPERT LECTURE

SUB MODULE 3:BLEEDING DISORDERSFACULTY OF MEDICINEUNIVERSITY OF BRAWIJAYA MALANG

No. 1Describe in brief the mechanisms of hemostasis !

The normal hemostasic response to vascular damage depends on closely linked interaction between : A. the blood vessel wallB. circulating platelets, and C. blood coagulation factors

A. Vascular factor Vessel injury vasoconstriction reduced blood flow allows contact activation of platelets and coagulationfactors

B. Platelets Vessel injury collagen exposure activation of platelet (adhesion, aggregation, secretion, and platelet procoagulant activity primary hemostatic plug platelet fusion stable hemostatic plug

C. Coagulation factor Vessel injury activation of tissue factor start the blood coagulation cascade thrombin fibrin stable hemostatic plug

The etiology of bleeding disorders :A. Vascular disorders1. Inherited vascular disordersa. Hereditary hemorrhagic telangiectasiab. Connective tissue disorder2. Acquired vascular disordersB. Thrombocytopenia1. Failure of platelet production2. Increased destruction of plateletsa. ITP : acute and chronicb. Infectionsc. Post transfusion purpurad. Drug-induced immune thrombocytopeniae. Thrombotic thrombocytopenia purpura (TTP) and Hemolytic uremic syndrome (HUS)f. Disseminated intravascular coagulationNo. 2Describe the etiology of bleeding disorders !

C. Disorders of platelet function1. Hereditary disorders2. Acquired disordersD. Defective of blood coagulation 1. Hereditary coagulation disordersa. Hemophilia b. Von Willebrand disease2. Acquired coagulation disorders

No. 3Describe in brief the pathophysiology of bleeding disorders ! The pathophysiology of bleeding disorders :A. Vascular disordersB. Platelet disorders : 1. Thrombocytopenia2. Defective platelet function C. Defective of blood coagulation

The Role of TPO in ThrombopoiesisModified with permission from Kaushansky K. Thrombopoietin. N Engl J Med. 1998;339:746-754.

No. 4Describe clinical features and laboratory findings to diagnose the etiology of bleeding disorders ! Diagnosis of bleeding disorders A. Clinical features : 1. Family history with bleeding disorders 2. The pattern of bleeding can predict the etiology a. Vascular and platelet disorders were associated with mucous membrane or skin bleeding, e.g. petechie, purpura, ecchymoses, gum bleeding, epistaksis, etc. b. Defective of blood coagulation cause bleeding into joints or soft tissues, e.g. joint bleeding, subcutaneous bleeding, muscular bleeding, intracranial hemorrhage, etc.

Purpura (reddish purple spots) leg ecchymosesPetechiaeSigns and Symptoms of Bleeding DisordersMRI of brain hemorrhage resulting from severe thrombocytopenia Abnormal bleeding of mucosal membranes

EcchymosesSigns and Symptoms of Bleeding DisordersPetekie & purpura

Signs and Symptoms of Bleeding DisordersMuscle bleedsJoint bleeds

B. Laboratory findings : 1. CBC especially platelet count 2. Blood film examination 3. Screening tests of blood coagulationNotes : PT (prothrombin time) APTT (activated partial thromboplastin time)

NoThe etiology of bleeding disordersPlatelet countBleeding timeClotting timePTAPTT1.Vascular disordersNNNNN2.Platelet disordersN / NNN3.Defective of coagulationNNN /

No. 5Describe the practical algorithms to diagnose the etiology of bleeding disorders !

The practical algorithms to diagnose the etiology of bleeding disorders