Hereditary haemochromatosis is diagnosed by simple blood tests. Your doctor may order the tests if your symptoms indicate haemochromatosis is possible or if you become aware a close relative has been diagnosed with haemochromatosis.
Parents, brothers, sisters and children of people diagnosed with haemochromatosis should be tested. However it is not necessary to test children before their late teens unless symptoms develop early.
These blood tests look for two indicators that signal someone may have haemochromatosis.
They measure Transferrin Saturation and Serum Ferritin
They are usually a fasting blood test.
Normal range for Iron studies:
Serum ferritin: 20-300 μg/L
Transferrin Saturation: 10-50%
Serum ferritin: 10-200 μg/L
Transferrin saturation: 10-45%
µg/L = micrograms per litre
If the results of these tests are above the normal range, they are repeated.
If the second test again exceeds the norm, a genetic test will check for the specific genetic markers of haemochromatosis.
The genetic test will show one of the following for the mutations C282Y and/or H63D of the HFE gene:
- Mutation not found
- Heterozygous (which means one faulty gene) or
- Homozygous (which means two faulty genes).
Haemochromatosis occurs when the genetic test result shows they are homozygous, that is they have two faulty genes.
A person who is heterozygous with one faulty gene is unlikely to experience any symptoms but is known as a “carrier” because they may pass the condition to a child.