Haematology Flashcards
Where does haemoglobin synthesis occur?
Cytoplasm
Defects in haem synthesis = small RBCs
Causes of microcytic anaemia?
Iron deficiency
Thalasseamia
lead poisoning
Congenital sideroblastic anaemia
What is circulating iron bound to?
Transferrin
What does transferrin saturation show?
Iron supply
When might transferrin saturation be raised?
Haemochromatosis
When is transferrin saturation decreased?
Iron deficiency
AOCD
Causes of chronic blood loss?
Menorrhagia
GI - Ulcers, tumours, NSAID
Haematuria
Epithelial changes in iron deficiency?
Pale
Koilonychia
Angular chelitis
Prescribing oral iron - names & side effects
Ferrous sulphate, ferrous fumarate and ferrous gluconate
Best taken on an empty stomach
Can irritate the gut - dark stool, constipation, N&V, abdo pain
Typically need to take for 2-3 months to replenish stores
Causes of MACROcytic anaemia
Megaloblastic anaemia
Non megaloblastic
Spurulous - reticulocytosis as reticulocytes are bigger or cold agglutinins which cause RBCs to clump together
Causes of megaloblastic anaemia?
B12 and folate deficiency
What does B12 bind to in small bowel ?
Intrinsic factor
What are some causes of B12 deficiency?
Vegan - comes from meat and eggs
Pernicious anaemia, gastritis, PPIs - prevent production of IF
Small bowel - malabsorption (crohns)
Where is folate absorbed?
Jejunum
Causes of folate deficiency
Haemolysis Pregnancy Exfoliating dermatitis Malignancy Inadequate intake Anticonvulsants Malabsorption
Dietary source of B12 and folate?
B12 = meat and eggs Folate = leafy green veg, fortified cereals
How much body stores of B12 and folate do we have?
B12 = 2-4 years Folate = 4 months
Daily dietary requirements for B12 and folate?
B12 = 1.5 Folate = 200
Are neurological symptoms more suggestive of B12 or folate deficiency?
B12
Changes seen in B12/folate deficiency?
Hypersegmented neutrophils
Treatment of magaloblastic anaemia
Treat cause:
Pernicious anaemia - lifelong B12 (hydroxycalbamin) injections
5mg oral folic acid
ONLY if life threatening - transfuse red cells
Cause of non-megaloblastic anaemias?
Alcohol
Liver disease
hypothyroid
^may not be associated with anaemia
Marrow failure - myelodysplasia, myeloma, aplastic anaemia
^always asssociated with anaemia
What’s raised HbA2 diagnostic of?
Beta thalassaemia trait
What are the normal quantities of :
HbA
HbF
HbA2
HbA >80%
HbF <1% (in adults)
HbA2 1.5-2%
Management of leukaemia?
MDT
Chemotherapy
Steroids
Bone marrow transplant
List some complications of chemotherapy?
Immunosuppression Neurotoxicity Infertility Secondary malignancy Cardiotoxicity Tumour lysis syndrome
What is tumour lysis syndrome?
Uric acid release from cells killed by chemotherapy, uric acid crystals in interstitial tissue and tubules of kidneys –> AKI
Management of tumour lysis?
Allopurinol or rasburicase are used to reduce the high uric acid levels
Treatment of flare of acute intermittent porphyria
IV Haem arginate
