Iron overload may develop in transfusion-dependent patients receiving red cells over a long period.

Problems usually develop once more than 30 g of iron accumulate. Each unit of red cells has 200 mg of iron; normal body stores are 3-4.0 g; daily losses are 1 mg.

Symptoms are similar to those seen in haemochromatosis with:

• endocrine dysfunction - for example, diabetes mellitus
• liver cirrhosis
• cardiac failure
• growth failure in children

Management:

• serum ferritin to estimate body iron stores
• desferrioxamine as a chelating agent, with vitamin C to enhance the therapeutic effect