Bleeding disorders

Bleeding Disorders

1. BLEEDING DISORDERS Dr Ambika Jawalkar

2. Classification Platelet disorders Coagulation disorders/defective coagulation mechanism Vascular disorders (Non-thrombocytopenic purpura )

3. I. Platelet disorders Thrombocytopenic purpura – deficiency of platelets *essential / idiopathic(ITP) *secondary Thrombasthenia – functional disorder of platelets (defect in adhesion / aggregation) eg : aspirin, large doses of penicillin, von Willibrand’s disease

4. II. Coagulation disorders Deficiency of clotting factors * Hemophilia Vitamin K deficiency Anticoagulant overdose Disseminated intravascular clotting (DIC)

5. III. Vascular disorders Drug induced damage to capillary wall Deficiency of vitamin C – Scurvy Allergic purpura Infections Senile purpura Connective tissue diseases

6. PURPURA Group of bleeding disorders Characteristic features are, * purple-colored petechial haemorrhages * bruises in the skin

7. CAUSES: Platelet disorders Thrombocytopenic purpura – primary, secondary Thrombosthenic purpura – vWD Vascular disorders – non-thrombocytopenic purpura

8. HEMOPHILIA “group of disorders occouring due to heriditary deficiency of coagulation” Characterized by bleeding tendency & increased clotting time. Hemoplilia A – 83% cases * Factor VIII (Classic Hemophilia) Hemophilia B – 15% cases * Factor IX (Christmas disease) Hemophilia C – 2% cases * Factor XI (PTA deficiency)

9. Laboratory tests in Bleeding disorders Tests that detect defects in THP Bleeding time Capillary fragility test Platelet aggregation test Platelet adhesiveness test Tests that detect defects in DHP Clotting time Prothrombin time Prothrombin consumption time Partial thromboplastin time (PTT) Activated partial thromboplastin time ( aPTT ) Thrombin time Clot retraction time

10. Bleeding time (BT) Time lapse between the skin prick and arrest of bleeding Estimated by Duke’s method & Ivy’s method Normal values by Duke’s method – 1-6 min. by Ivy’s method – 3-6 min. BT is prolonged in Purpura & normal in Hemophilia

11. Clotting Time (CT) Time between skin prick & formation of first fibrin thread Estimated by Capillary tube method & Lee-White method Normal values by capillary tube method is 3-6 min. by lee-white method is 8-12 min. Prolonged in hemophila

12. Prothrombin time (PT) Quick’s one stage method Commercially available tissue thromboplastin & CaCl2 is added to oxalated or citrated plasma – incubated at 37oC Normal value is 11-16 sec. Extrinsic system is tested here.(no platelets involved) Used to monitor anti-coagulant therapy Increased in liver failure, vit K deficiency

13. Partial Thromboplastin Time (PTT) Also known as KCCT – Kaolin cephalin clotting time. Detects minute coagulation defects Normal is 40 sec. Measures intrinsic pathway Used to monitor Heparin therapy Is prolonged in Hemophilia, vWD

14. Thrombin Time (TT) Measures final step in coagulation i.e , availability of functional fibrinogen Normal is 10 sec. Is prolonged in hypofibrinogenemia , dysfibrinogenemia , DIC & hepain therapy.

15. Clot retraction time Measures time needed for contraction of an undisturbed clot. Indicates function & number of platelets Normally begins within 2 hours and completed within 24 hours Is retarded in thrombocytopenia Clot is small & soft in thromboasthenia