Bleeding Disorders Flashcards
Vascular Disorders
Problems with vessel wall
Inherited: hereditary haemorrhagic telangiectasia, Elhers-Danlos syndrome
Aquired: scurvy, steroids, senile
Platelet Disorders
Thrombocytopenia - treated with steroids/IV immunoglobulins, thromboietin agonists, immunosuppresion or splenectomy
Tests of Coagulation Disorders
APTT: activated partial thromboplastin time - assesses intrinsic pathway
PT: prothrombin time - assesses extrinsic pathway
TT: thrombin time - assesses terminal common pathway
Fibrinogen level/Clotting factor assays/D-dimers
Haemophilia A
A - factor VIII deficiency, B - factor IX deficiency
Spontaneous bleeding
Prolonged APTT, normal PT, low VIII/IX levels
Treatment: infusions of factor
Coagulation Disorders - acquired
Liver disease: deficient synthesis of clotting proteins and impaired platelet function & fibrinolysis
Vitamin K deficiency
Disseminated Intravascular Coagulation (DIC): release of pro-coagulant material into circulation - results in consumption of clotting factors, causing bleeding & thombolysis
Anti-coagulant drugs
Iatrogenic - o/d of anticoagulant drugs
types of anti-coagulant: heparin (for MIs, PEs, DVTs), warfarin (for PEs, DVTs, AF), DOACs (direct thrombin inhibitors and factor Xa inhibitors)
Vitamin K deficiency
Required for gamma carboxylation of factors II, XII, iX, X
Inhibited by warfarin
Deficiency due to malabsorption, biliary obstruction and haemorrhagic disease of the newborn
von Willebrand Disease
autosomal dominant
vWF = large multimeric protein that carries factor VIII in blood
vWF binds platelets to endothelial collagen
vWD = deficiency of vWF and factor VIII in plasma
Testing: prolonged APTT, normal PT, low vWF from Weibel-Palade storage bodies
Meningococcal DIC
Prolonged PT, APTT, TT
Low fibrinogen and low platelets
raised D-dimers or FDPs
causes: cancer, sepsis, obstetric disasters