Iron Deficiency and Anaemia of Chronic Disease Flashcards
In what state is the iron in the haem group of haemoglobin?
Fe2+ (ferrous)
How much iron do you need per day to maintain the production of red blood cells?
20 mg/day
How can iron be lost under normal, non-pathological conditions?
Desquamation of cells in the skin and gut
Bleeding (menstruation is one of the largest causes of loss of iron from the body in women)
How much iron does the human diet normally provide?
12-15 mg/day
State some natural foods that are high in iron.
Meat and fish
Vegetables
Whole grain cereal
Chocolate
Which form of iron cannot be absorbed?
Fe3+ (ferric)
What effect does drinking tea have on iron absorption?
Cups of tea promotes the conversion of Fe2+ to Fe3+
Why do meat and fish eaters have an advantage over vegetarians in terms of iron absorption?
They will absorb iron in the haem form
State three systemic factors that increase demand for iron absorption.
Iron deficiency
Anaemia/hypoxia
Pregnancy
Which channel, on the basement membrane of intestinal epithelial cells, allows movement of iron into the circulation?
Ferroportin
What is a key regulator of iron absorption that affects ferroportin?
Hepcidin
How is the level of hepcidin affected?
There are certain proteins (such as hepcidin) that have iron-responsive elements in their genes
So iron is part of the complex that switches on hepcidin transcription
How is iron stored within cells?
In ferritin micelles
What transports iron in the circulation?
Transferrin
State three parameters that can be measured that involve transferrin?
Transferrin
Transferrin Saturation
Total Iron Binding Capacity (TIBC)
What is the normal transferrin saturation?
20-40%
What is anaemia of chronic disease?
Anaemia that is seen in patients with chronic disease
What typical signs of anaemia will anaemia of chronic disease patients NOT have?
They will NOT be bleeding
They will NOT be iron deficient, B12 deficient or folate deficient
They will NOT have any bone marrow infiltration
State some laboratory signs of being ill.
Raised C-reactive protein (CRP) Raised Erythrocyte Sedimentation Rate (ESR) Raised Ferritin Raised Factor VIII Raised Fibrinogen Raised Immunoglobulins
State some causes of anaemia of chronic disease.
Chronic infections – e.g. TB/HIV
Chronic inflammation – e.g. SLE, rheumatoid arthritis
Malignancy
Miscellaneous (e.g. cardiac failure)
What is the underlying cause of ACD?
ACD is due to the cytokine release that happens when someone is unwell
The cytokines block utilisation of iron by red blood cells
They also stop erythropoietin from increasing
Stop iron flowing out of cells
Increase production of ferritin
Increased death of red cells
Give examples of cytokines involved in ACD.
TNF
Interleukins
State four broad causes of iron deficiency.
Bleeding
Increased use (e.g. growth, pregnancy)
Dietary deficiency (e.g. vegetarian)
Malabsorption (e.g. Coeliac disease)
State some other investigations that can be performed.
Antibodies for coeliac disease
Check for urinary blood loss
