Deironing process from notes of Larry Dunn:
Iron content based on
staining reactions are usually graded "0 - 4". So you have a significant amount
of iron (with a 3), but there was room for more. The quantitative determination
of iron in the liver is more of a hard and fast number. In the stages leading to
iron deficiency anemia the first stage is iron depletion where iron stores begin
to be depleted but there is still plenty to support normal RBC production and
normal Hgb/hematocrit are present. Stage II is referred to as "iron deficient
erythropoiesis"(RBC production). During this stage, iron content based on the
staining reaction is "0", meaning there is no detectable iron. At this stage,
FEP(free erythrocyte porphyrins) become increased as the earliest marker that
the person has iron deficient erythropoeisis (aside from performing a bone
marrow)(FEP is not a routinely ordered test)The heme part of hemoglobin consists
of ferrous iron + a porphyrin compound (protoporphyrin IX). As soon as we run
out of iron, there is still plenty of the porphyrin being produced, so the
free(extra) erythrocyte porphyrin increases. During stage II, Hgb/HCT are still
normal. Stage III is iron deficiency anemia with a decreased Hgb/HCT (Hgb<10).
When HH patients are de-ironed and their Hgb/Hct doesn't "bounce back", they
have reached stage three. At this point iron stores(zero) are not able to
maintain a normal rate of erythropoeiesis. Stage II ferritin levels are usually
between10-20. Stage III levels are usually less than 10. Individuals may vary in
their numbers. We are all unique and don't respond "exactly" the same when it
comes to evaluating lab numbers. What happens in the liver to the stored iron?
If the iron-ferritin-hemosiderin physiology is the same in the liver as it is in
the bone marrow (I don't know why it would be different), then the iron stores
(including hemosiderin) are also gone in the liver. I think that the Hgb/HCT
levels that don't "bounce back" are the best indicators of de-ironing, because
that is the body's way of saying "where's the iron?" Ferritin levels can
fluctuate at times, and although it is usualy a reliable indicator of iron
stores, individual results may be misleading. I am not a doctor, I am a Medical
Technologist who is also a teacher of Medical Technology(explains why I can't
get to the point sometimes). The info I have shared is pretty solid based on
current Hematology sources. I am just passing it on. If I have missed something
or misrepresented something, then I hope Dr. Clayton or Dr. Sullivan will set
us(me) straight.
Sincerely
Larry Dunn M.S., MT(ASCP)
resources:
Clinical Hematology and Fundamentals of Hemostasis; Harmening,PhD;1997;pp. 97-112
Textbook of Hematology; McKenzie,PhD;1996;pp.123-144
Clinical Diagnosis and
Management by Laboratory Methods; Henry, MD;1996 pp.617-620.