Iron Metabolism Disorders Flashcards
What three ways can iron be manhandled?
Iron deficiency
Iron malutilisation
Iron overload
What can cause iron deficiency?
Insufficient intake
Blood loss
What can cause an insufficient iron intake?
Diet
Malabsorption- Coeliac’s disease
Where can blood be lost from?
Bleeding
Menorrhagia
Gastrointestinal- Tumours, Ulcers, NSAIDs, Parasites
Haematuria
What are the symptoms of iron deficiency?
Epithelial changes -Skin -Koilonychia -Brittle nails -Angular stomatitis -Brittle hair Hypochromic microcytic anaemias Dysphagia and glottitis
What are some epithelial changes seen in iron deficiency?
- Dry skin
- Koilonychia
- Brittle nails
- Angular stomatitis
- Brittle hair
How do you confirm iron deficiency?
Combination of anaemia (decreased functional iron) and decreased iron stores (low serum ferritin)
How do you diagnose iron deficiency?
Blood count and film
Decreased serum ferritin
What is seen in blood count and film in iron deficiency?
Microcytic hypochromatic cells
Misshapen cells
Condocytes (target cells)
What causes iron malutilisation?
Anaemia of chronic disease- inflammation increases ferritin and hepcidin synthesis (blocks iron release).
Describe iron malutilisation
Increases iron stores and decreases functional iron. Occurs to reduce supply of iron to pathogens.
What are the two forms of iron overload?
Primary
Secondary
Describe primary iron overload/what causes it
Long term excessive iron absorption with excess being stored in tissues over macrophages.
Give a primary iron overload condition
Hereditary haemochromatosis
Describe hereditary haemochromatosis
Due to HFE gene mutations leading to decreased hepcidin resulting in increased iron absorption.
What are the symptoms of hereditary haemochromatosis
Weakness/fatigue Joint pains Impotence Arthritis Cirrhosis Diabetes Cardiomyopathy Presents in middle to late age Iron >5g
What serum ferritin levels characterise hereditary haemochromatosis?
> 300microg/l men
>200microg/l women
How do you diagnose hereditary haemochromatosis?
Genetic testing- HFE gene mutations
Transferrin saturation >50%- sustained over multi visits
Increased iron stores
Liver biopsy
How do you treat hereditary haemochromatosis?
Weekly venesection- remove 500ml blood. Aim to reduce iron stored.
Who should be screened for hereditary haemochromatosis?
First degree relatives
Children
Why should you screen for hereditary haemochromatosis?
As may be asymptomatic until end stage organ damage has occurred.
What can cause secondary iron overload?
Transfusion
Iron loading anaemia
What two forms iron loading anaemia are there?
Massive ineffective erythropoiesis
Refractory hypoplastic anaemias
Red cell aplasia
Myelodysplasia (MDS)
Give some examples of missive ineffective erythropoiesis
Thalassaemia
Sideroblastic anaemias
