Overview
- Serum iron assesses transport compartment.
- Transported in plasma bound to transferrin (beta-2 globulin).
- Synthesis of hemoglobin takes precedence over demands for other iron compounds so serum iron is more sensitive indicator of deficiency than MCV
, MCH , MCHC . - Serum [iron] only falls when storage iron depleted.
- Severe iron deficiency (reduced intake or blood loss) can cause microcytic hypochromic anemia .
- Measure either serum iron (plasma bound to transferrin) or serum total iron binding capacity (TIBC).
- Bone marrow iron (assessed morphologically in a bone marrow aspirate) is used to asses iron storage.
- Iron is not seen in feline bone marrow in health so cannot use marrow to assess decreased iron since the absence of iron is within normal limits.
Uses
In combination
- Investigation of anemia .
Other points
- Iron important as part of enzymes or cofactor for energy-producing metabolic pathways, eg tricarboxylic acid cycle.
- Important component of hem-containing compounds (hemoglobin, myoglobin, cytochromes).
- Important in enzymes of mitochondria.
Result data
Normal (reference) values
- Serum iron 15-42 umol/l (84-233 ug/dl).
- Conversion factor: ug/dl x 0.1791 → umol/l.
Abnormal values
Decreased serum iron- Anemia due to:
- Iron deficiency.
- Acute phase inflammatory reactions.
- Renal disease .
- Chronic inflammation/malignancy (anemia of chronic disease).
Increased serum iron
- Hemolytic anemia (more iron required for increased erythropoietic activity).
- Hypoplastic/aplastic anemia.
- Iron overload (repeated transfusion ).
- Liver disease .
Increased TIBC
- Iron deficiency +/- anemia.
- Pregnancy +/- iron deficiency.
Decreased TIBC
- Chronic infections.
- Malignancy.
- Renal disease .
- Protein malnutrition.
Sources
Publications
Refereed papers
- Papich M G (1990) Topicosis from over the counter human drugs. Vet Clin North Am Small Anim Pract 20 (2), 431-451.
- Stone M S (1990) Differentiation of anemia of inflammatory disease from anemia of iron deficiency. Comp Cont Educ 12 (7), 963-966.
Other sources of information
- Kaneko J J, Harvey J W & Bruss M L (eds) (1997) Clinical Biochemistry of Domestic Animals. 5th edn. Boston: Academic Press. ISBN: 0 1239 6305 2.
