Iron overload

When to suspect this adverse reaction

Patients who are chronically dependent on red cell transfusions (e.g. thalassaemia, red cell aplasia) are at the biggest risk of iron overload. The body cannot remove excess iron which then over time accumulates in certain organs such as the liver, heart and endocrine organs affecting their function.

Early symptoms are often vague such as muscle weakness, fatigue and weight loss. Later, skin pigmentation, arthropathy, diabetes, impotence, cardiac failure and hepatic dysfunction can occur.

Usual causes

Each unit of red cells contains about 250 mg of iron and the average rate of iron excretion is only about 1 mg/day.  With the cumulative effect of regular transfusions iron overload can occur and should be suspected after 10 transfusions.

Investigation

Severity of iron overload can be determined by measuring serum ferritin, MRI which assesses iron concentration in the heart and liver and occasionally by liver biopsy.

What to do

Treatment is aimed at the removal of accumulated iron in the tissues e.g. using iron-chelating agents which form complexes with iron and promote its excretion.