eLFH - Haematology Flashcards
Classification of anaemia
Microcytic (MCV < 80 fL)
Normocytic (MCV normal)
Macrocytic (MCV > 96 fL)
Polycythaemia classification
Absolute - increased red blood cell mass
Relative - reduced plasma volume e.g. dehydration
Causes of neutrophilia
Bacterial infection
Inflammation / necrosis - e.g. MI, trauma
Neoplasms
Corticosteroids
Causes of neutropenia
Chemo / radiotherapy
Drug reactions - e.g. carbimazole
Bone marrow infiltration
Causes of lymphocytosis
Viral infection
Thyrotoxicosis
CLL
Causes of thrombocythemia
Essential thrombocythemia
Inflammation following splenectomy
Malignancy
Acute phase reaction
Causes of thrombocytopenia
Artefactual
Idiopathic / Immune
Drugs - e.g. heparin, valproate
HELLP syndrome
Causes of normal platelet count but abnormal function
Aspirin
Clopidogrel
von Willebrand’s disease
Causes of microcytic anaemia
Iron deficiency - most common
Anaemia of chronic disease (or normocytic)
Thalassaemia
Sideroblastic anaemia
Causes of iron deficiency anaemia
Occult bleeding from NSAIDs / Aspirin
GI tumours
Malabsorption - e.g. coeliac, post gastrectomy
Iron study investigations
Blood film
Ferritin
Iron level
Transferrin saturations
TIBC (total iron binding capacity) - raised in iron deficiency
Iron deficiency blood film results
Microcytic hypochromic RBCs
Anisocytosis - variable size RBCs
Poikilocytosis - variable shape RBCs
Transferrin saturation calculation
Transferrin sats = Iron / TIBC
Causes of normocytic anaemia
Anaemia of chronic disease
Acute blood loss
Endocrine disorders - e.g. hypothyroidism
Aplastic anaemia
Haemolytic anaemia (or macrocytic)
Difference between sickle cell anaemia and sickle cell trait
Sickle cell anaemia are anaemic with high reticulocyte count
Sickle cell trait are not anaemic
Trait have normal growth, exercise tolerance and life expectancy
Trait only get sickle cell crises with extreme hypoxia
Investigations for sickle cell disease
Blood film - sickled RBCs
Solubility test - positive in both anaemia and trait
Hb electrophoresis
Haemoglobin differences between sickle cell anaemia and sickle cell trait
Classification of Absolute Polycythaemia
Primary
Secondary
Primary polycythaemia examples
Polycythaemia rubra vera
Secondary polycythaemia examples
Appropriate increase in erythropoietin - respiratory disease, congenital cyanotic heart disease, high altitude, heavy smoking
Inappropriate increase in EPO - renal, liver, cerebellar tumours
Oral iron supplements rate of increase in Hb
Raise Hb by around 1 g/dL per week (note units used equivalent to rise by 10 in other units)
Causes of prolonged thrombin time
Fibrinogen deficiency
Dysfibrinogenaemia
Heparin
DIC
Causes of prolonged bleeding time
von Willebrand’s disease
Blood vessel defects
Platelet abnormalities
Causes of DIC
Sepsis
Haemolytic transfusion reactions
Pre-eclampsia
