Case 4 SBA Flashcards
How does iron deficiency cause anaemia?
Reduces the amount of haemoglobin produced, so is microcytic
How does renal failure cause anaemia?
No EPO produced
How does cancer or chronic inflammation cause anaemia?
Turns on hepcidin so less iron available
How does thalassemia cause anaemia?
Not enough haemoglobin produced
How does B12 and folate deficiency cause anaemia?
Necessary for methylation in DNA synthesis so macrocytic
For the synthesis of what are folic acid derivatives needed?
Purine and thymidine
What causes a B12 deficiency?
Diet, lack of intrinsic factor (pernicious anaemia), removal of terminal ileum
How do drugs cause anaemia?
Make it harder to absorb B12
Can cause immune system to confuse RBCs with foreign substances so can lead to haemolytic anaemia
Aetiology of microcytic anaemia
Nucleus divides before sufficient haemoglobin is synthesised, leads to small pale cells
Aetiology of macrocytic anaemia
DNA can’t replicate properly so a megaloblast forms
What do red blood cells need to be produced?
Free iron, haem, globin proteins, B12, folate, DNA synthesis, normally functioning bone marrow
What are the oral iron supplements for IDA?
Ferrous sulfate, ferrous gluconate, ferrous fumarate
Side effects of IDA treatment
GI upset, diarrhoea, constipation, nausea, epigastric pain, iron toxicity
Describe the treatment for IDA
Oral replacement daily until 3 months after resolution
Should take on an empty stomach and with orange juice to aid absorption
Avoid calcium, tea, and coffee for 1-2 hours after to promote absorption
What reduces the side effects of IDA treatment and what are the consequences of this?
Taking the tablets with food but this reduces absorption
What happens if daily oral iron replacement not tolerated in IDA treatment?
Move to alternate days
If still not tolerated then move to IV ferrinject
Describe the treatment for folate deficiency
5mg folic acid daily for four months, or longer if the cause is persistent
Treatment of folate deficiency in pregnancy
400 micrograms daily until 12 weeks
5mg if high risk
What embryological defect can folic acid supplements cause?
Neural tube defects leading to spina bifida
Side effects of folic acid treatment
Nausea, GI upset, anorexia, abdominal distension, flatulence, immune response
Treatment of renal anaemia
EPO replacement darbepoeitin subcutaneously every 1-4 weeks
Side effects of darbepoeitin treatment (SHEATS)
Skin reaction, risk of embolism and thrombosis, increased risk of stroke, arthralgia, hypertension
Describe treatment for B12 deficiency
IM preparations e.g. hydroxocobalamin every 2-3 months
Daily oral preparation may be needed for a dietary cause
Side effects of B12 deficiency treatment
Hot flushes, nausea, vomiting, diarrhoea, dizziness, pain at injection site
Classification of acute anaemia
Macrocytic or normocytic
Causes of acute anaemia
GI bleed, drugs, haemolytic, bone marrow failure
