Iron Deficiency Anaemia Flashcards
What is anaemia defined as?
A Hb below the normal range
Is the normal Hb range consistent with age?
No, it varies
What is anaemia defined as in neonates?
Hb below 140g/L
What is anaemia defined as in children aged 1 month-12 years?
Hb below 100g/L
What is anaemia defined as in children aged 1 year to 12 years?
Hb less than 110g/L
What can anaemia result from?
A number of different mechanisms
Give an example of a mechanism by which anaemia can result?
Reduced red cell production due to ineffective erythropoiesis
What can cause reduced red cell production due to ineffective erythropoiesis?
Iron deficiency
What is the importance of iron deficiency as a cause of anaemia?
It is one of the most common causes of anaemia
What is iron?
A mineral
What is iron important for?
Formation of red blood cells in the body, particularly as a critical component of haemoglobin
How is iron absorbed?
Primarily in the small intestine, in particular the duodenum and jejenum
What happens to iron after being absorbed in the small intestine?
It travels through the blood bound to transferrin, and eventually ends up in the bone marrow, where it is involved in RBC formation
What happens to iron when RBCs are degraded?
The iron is recycled by the body and stored
What are the main causes of iron deficiency?
- Inadequate intake
- Malabsorption
- Blood loss
Who is inadequate iron intake common in?
Infants
Why is inadequate iron intake common in infants?
Because additional iron is required for the increase in blood volume accompanying growth, and to build up the child’s iron stores
What sources might iron come from?
- Breastmilk
- Infant formula
- Cow’s milk
- Solid’s introduced at weaning
Describe the iron content of breastmilk
It has a low iron content, but 50% is absorbed
Describe the iron content of infant formula
It is supplemented with adequate amounts of iron
Describe the iron content of cow’s milk
It has a higher content than breastmilk, but only about 10% is absorbed
In terms of diet, why might iron deficiency occur?
- Introduction of mixed feeding beyond 6 months old
- Diet with insufficient iron-rich foods
When is iron absorption markedly increased?
When eaten with food rich in vitamin D
When are most infants and children asymptomatic until?
Hb drops below 60-70g/L
What happens to presentation as anaemia worsens and becomes symptomatic?
- Children tire easily
- Young infants feed more slowly than normal
- Appear pale
- Pica
Is pallor a reliable sign in anaemia?
Not unless it is confirmed by pallor of the conjunctivae, tongue, or palmar creases
What is pica?
Inappropriate eating of non-food materials
Does iron deficiency anaemia affect cognition?
There is evidence that iron deficiency anaemia may be detrimental to behaviour and intellectual function
What should the history include in iron deficiency anaemia?
Asking about blood loss and symptoms/signs suggestive of blood loss
What might the FBC show in iron deficiency anaemia?
- Low MCV
- Low mean cell haemoglobin
- Low serum ferritin
What are the differential diagnoses of microcytic anaemia?
- ß-thalassaemia
- Anaemia or chronic disease, e.g. due to CKD
What does the management of iron deficiency anaemia involve for most children?
- Dietary advice
- Supplementation with oral iron
Give 4 examples of iron rich foods
- Red meat
- Liver
- Kidney
- Oily fish
By how much should iron supplementation increase Hb with good compliance?
Around 10g/L/week
What are the best tolerated preparations of iron supplementation?
- Sytron
- Niferex
What can cause failure to respond to iron supplementation?
Usually indicates poor compliance, but other causes, e.g. malabsorption, chronic blood loss, should be considered
Is blood transfusion necessary for dietary iron deficiency?
It should never be
Why should blood transfusion never be necessary for dietary iron deficiency?
Because even children with a Hb as low as 20-30g/L due to iron deficiency have gradually reached this level, and therefore can tolerate it
What are the complications of iron deficiency anaemia?
Problems with growth and development
