Saturday, May 18, 2013
Why such low ferritin? iron avid?
42 yo normally-menstruating female, irish/italian, no red meat, very little heme iron at all in diet. No *known* history of HH, but I`m being tested for HFE genes now. Results soon. Have never given blood or had any HH treatments of any kind.
Very normal iron indices in 1998 (iron was 88 ug/dL, tsat was 23%), except for TIBC (385 ug/dL) (Quest Diagnositcs, AMBA)
In 2003 - High iron (244 ug/dL) and tsat (75%) but low ferritin (24 ng/mL) - TIBC was 325 ug/dL (Quest Diagnositics/AMBA, except for ferritin which was tested at Stanford Hospital)
Retested in 2007: iron 199 ug/dL, tsat 53%, TIBC 375 ug/dL, and ferritin 14 ng/dL (Quest Diagnostics/AMBA, except for ferritin which was tested via a blood draw at my dr`s office, I don`t know what lab)
If I have such high iron floating around, and not being sequestered into ferritin proteins, is it more likely to cause harm? Why is the ferritin not upregulating? Wouldn`t it be healthier to have a higher ferritin count if the tsat is so high? Then I could drop them all with phlebotomy. Would phlebotomy be contraindicated in light of the low ferritin? Is there a way to test for hemosiderin levels? Are there other storage proteins that I can have checked? If I don`t have HH, what could be causing my weird iron indices?
Too many questions, I know ... if you answer a few, I`ll be appreciative.
The best way I could summarize the rather confusing-looking tests is that they're each measuring different parts of iron metabolism.
First, there is no useful test of hemosiderin deposits. It wouldn't have any special clinical considerations associated with it anyway.
Other storage proteins wouldn't be terribly relevant in this situation. The one thing that might be helpful to check is to rule out inflammation as an underlying cause. Checking c-reactive protein or erythrocyte sedimentation rate (ESR) might be helpful in that regard.
It is at least possible that the patient could have hereditary hemochromatosis, but still be iron deficient. That would give you both a high iron saturation index as well as a low ferritin. Certainly checking the genetic status would be helpful in this situation.
Please feel free to contact us again when the results of the genetic assay are available.
Mark Wurster, MD
Former Clinical Assistant Professor of Internal Medicine
College of Medicine
The Ohio State University