This is a guideline from the BSH on investigating and managing a raised ferritin published in 2018. I’m going to summarise it, but there is a lot more in the guideline, which would be useful to refer to if you have a puzzling patient.
- In healthy people, the ferritin level is directly proportional to the body’s iron stores.
- Ferritin is a protein in the blood that contains iron.
- Ferritin is not a very good marker of iron stores in people with severe CKD.
Transferrin saturation. Transferrin carries iron around the body. If there isn’t enough iron, transferrin saturation will be low. Too much iron and transferrin saturation will be high. Ideally serum analysis should be done on a fasting sample, but mostly it isn’t. If you have a borderline result, it may be worth repeating on a fasting sample. It is worth noting that acute infections, menstrual bleeding and recent blood donation can all reduce transferrin saturation. This may mask an iron overload condition.
What normal variations are there in ferritin levels?
I was not aware of any of the following, so thought it worth noting.
- Men have higher levels on average than women.
- Women have lower levels while menstruating, then after menopause, their levels go up.
- Black adult males have higher levels than white males at all ages.
- Black adult females have higher levels than white females only after menopause.
- It is more common to find very high levels of ferritin in people of Afro-Caribbean or Asian descent than it is in people of White or Hispanic descent. However it is rare to find haemochromatosis in people of Afro-Caribbean or Asian descent.