Haematological Flashcards
Name 4 myeloproliferative neoplasms
Chronic myeloid leukaemia
Polycythaemia vera
Essential thrombocythemia
Primary myelofibrosis
What are the features of bone marrow failure
Neutropenia
Anaemia (normocytic)
Thrombocytopenia
Define leukaemia
Abnormal proliferation and differentiation of leucocytes or their precursor cells.
What are most cases of leukaemia
De novo (not inherited)
Describe acute leukaemia
Result from failure of lymphoid or myeloid progenitor cells to differentiate, with resultant uncontrolled proliferation of these immature blast cells
Describe chronic leukaemia
Result from the uncontrolled proliferation of cells at a later stage of differentiation.
Define primary haemostasis
Initiation and formation of platelet plug = platelet activation
Define secondary haemostasis
Formation of fibrin clot = intrinsic and extrinsic coagulation factors
How do NSAIDs affect platelet activation
Inhibits thromboxane formation
How does dabigatran affect platelet activation
Inhibits thrombin
How does clopidogrel affect platelet activation
P2Y12 inhibitor - antiplatelet
Describe the affect of warfarin on the clotting cascade
Blocks vitamin K
1972 - factor 10, 9, 7, 2
What is the intrinsic pathway of the coagulation cascade initiated by
Endothelial collagen
Summarise the intrinsic pathway
12 - 11 - 9 - 8 - 10 - 10a
What is the extrinsic pathway of the coagulation cascade initiated by
Tissue factor expressed by immune cells and endothelium
Summarise the extrinsic pathway
7 - 10 - 10a
Summarise the common pathway
10a - prothrombin (II) - thrombin (IIa) - fibrinogen - fibrin (factor 13 - reinforces fibrin)
How does heparin inhibit the coagulation cascade
Via antithrombin III (prothrombin)
How does rivaroxaban inhibit coagulation cascade
Via factor Xa directly
Which pathway does APTT show
Intrinsic
What pathway does PT show
Extrinsic
What pathway does PT and APTT show
Common pathway
Describe tranexamic acid
Reduces the conversion of plasminogen to plasmin, preventing fibrin degradation and increasing clot stability
What would be seen on a blood film of a patient with iron deficiency anaemia
Hypochromic red cells
Hypochromic microcytosis
Microcytic red cells
Pencil cells
Anisocytosis
Poikilocytosis
Thrombocytosis (raised platelet count)