Formative Flashcards
What does an isolated prolonged APTT reflect?
Deficiency of factors in the intrinsic pathway of coagulation;
Factor 8, 9 = haemophilia
Heparin
APS
What does an isolated prolonged PT time reflect?
Deficiency of factors in the extrinsic pathway
Factor 7 and vWF
Warfarin
What is DIC?
Consumptive coagulopathy due to abnormal activation of coag system with deposition of thrombi in micro and macro vasculature
In blood tests, how will DIC present?
Prolonged PT
Prolonged APTT
Low platelets
Low fibrinogen
What causes TRALI?
Anti-leucocyte antibodies in donation that bind to the patients white cells and cause an acute lung injury
What mutation is present in those with myeloproliferative polycythaemia?
JAK2 gene
What should be investigated in someone with a high Hb with no history to suggest secondary polycythaemia?
Polycythaemia rubra vera
JAK 2 gene
What does rituximab target?
CD20 - expressed on B cells and B cell lymphomas
What does imatinib target?
BCR-ABL 1 tyrosine kinase
What do bence jones protein reflect?
The excretion of monoclonal (kappa or lambda) immunoglobulin light chains
What is the appearance of an eosinophil?
Bi-lobed (spectacle) shaped nuclei
Red stained cytoplasmic granules
What is AML?
Bone marrow based malignancy where there is a block in differentiation and an excess of primitive cells
What ic CLL?
NO block on differentation but a failure of cell death resulting in a steady accumulation of cells
Seen as an excess of small mature lymphocytes in the blood (often smear cells)
How is a diagnosis of CLL confirmed?
Peripheral blood immunotyping
Why will pancytopenia occur in megaloblastic anaemia?
B12 is required for nuclear maturation in all 3 haemopoietic lineages
What will the blood film show in megaloblastic anaemia?
Macroovalocytes
Hypersegmented neutrophils
Why does marrow failure occur in AML?
Excessive proliferation of primitive cells (myeloblasts)
What is an auer rod?
PATHOGNOMONIC OF AML
Abnormalities of granulation in blasts
What is essential thrombocythaemia?
Chronic myeloproliferative disorder characterized by excess production of platelets in the bone marrow and an increased risk of thrombosis
What causes HbS?
Point mutation in codon 6 resulting in a substitution of glutamic acid to valine in the beta chain
What is a different way to describe a spherocyte?
Red cells that have lost central pallor
What is the treatment for autoimmune haemolytic anaemia?
Steroid (1 mg/kg of pred per day)
Folic acid
What is the mode of action of clopidogrel?
Selectively inhibits binding of ADP to platelet receptor and the subsequent ADP mediated activation of glycoprotein GP2b/3a complex therefore inhibiting platelet activation
What is the mode of action of aspirin?
Irreversible inactivates cyclooxygenase 1
What is the mode of action of rivaroxaban?
Competitively inhibits factor 10a
Factor 10 along with 5a form the prothrombinase complex which converts prothrombin to thrombin
What is the treatment for a sickle chest crisis?
Exchange transfusion
What is vWF deficiency?
Disorder of primary haemostasis due to deficiency of vWF which bridges platelets to sub-endothelial collagen following endothelial injury
This affects platelet adhesion at the site of injury
What causes myelodysplasia?
Stem cell malignancy that results in ineffective haematopoiesis
What can myelodysplasia progress to?
AML
