Investigating iron status in microcytic anaemia.

The investigation of possible iron deficiency has changed in recent years. Traditionally, measurements of iron and iron binding capacity were performed by laboratories, but serum ferritin has now become established as a more reliable test for iron deficiency, although results in both situations can be influenced by the presence of acute or chronic inflammation. In populations in which the prevalence of haemoglobinopathy genes is low, the finding of a microcytic anaemia is considered by some to be sufficient to indicate iron deficiency anaemia. However, this can lead to an erroneous diagnosis, as shown in the cases below.