Haematology Flashcards
What is the haematocrit?
Volume % of RBCs in blood
Useful when looking for polycythaemia
What is the mean corpuscular haemoglobin (MCH)?
Mean Hb quantity in RBCs - effects colour ‘chromic’
Causes of microcytic anaemia?
Iron deficiency
Thalassemia
Causes of normocytic anaemia?
Blood loss
Anaemia of chronic disease
Haemolytic anaemia
Sickle cell
Causes of macrocytic anaemia?
B12/folate deficiency (megaloblastic)
Alcohol, pregnancy, liver disease, hydroxycarbamide, hypothyroidism
What is haptoglobin?
Acute phase marker of RBC destruction. Normally binds to free Hb so may be severely reduced in haemolysis
4 drugs that cause agranulocytosis
4 'c's Carbimazole Carbemazepine Colchicine Clozapine
What is a TIBC? (Total iron binding capacity)
Looks at how many binding sites are available on transferrin.
Low - seen in Fe overload
High - seen in anaemia
What does TSAT show?
Should be about 30%
If high then Fe overload
If low then anaemia
Features of haemolytic anaemia
Increased RBC breakdown (raised BR, raised LDH, raised urobilinogen, reduced haptoglobin, pigmented gallstones)
Increased RBC production (increased reticulocytes)
3 reasons for abnormality in inherited haemolytic anaemia
Membrane defect
Enzyme abnormality
Hb abnormality
Examples of membrane problems in HA
Hereditary spherocytosis
Heridatary elliptocytosis
Examples of membrane problems in HA
G6PD deficiency
Pyruvate kinase deficiency
Hereditary spherocytosis
Disorder of spectrin
RBCs lose shape in circulation, they become rounded so harder to carry o2 - destroyed by extravascular system
Variable anaemia + jaundice
Film: spherocytes with no central pallor and small
Which condition do fava beans cause anaemia in?
G6PD deficiency
G6PD deficiency
G6PD only source of NADPH in RBC so only protection from oxidative stress
When oxidative stress (infections, fava beans, drugs) - cause anaemia + a non-spherocytic anaemia