Clinical Significance
Iron, Total and Total Iron Binding Capacity - Serum iron quantification is useful in confirming the diagnosis of iron-deficiency anemia or hemochromatosis. The measurement of total iron binding in the same specimen may facilitate the clinician's ability to distinguish between low serum iron levels caused by iron deficiency from those related to inflammatory neoplastic disorders. The assay for iron measures the amount of iron which is bound to transferrin. The total iron binding capacity (TIBC) measures the amount of iron that would appear in blood if all the transferrin were saturated with iron. It is an indirect measurement of transferrin concentrations but expressed as an iron measurement. To obtain the percent saturation, the serum iron is divided by the TIBC which gives the actual amount of saturated transferrin. The percent saturation is low in iron deficiency and high in iron storage diseases.


Preferred Specimen(s)
1 mL serum

Alternative Specimen(s)
Plasma collected in: Sodium heparin (green-top) tube or lithium heparin (green-top) tube

Minimum Volume
0.5 mL

Transport Container
Serum Separator Tube (SST®)

Transport Temperature
Room temperature

Specimen Stability
 Room temperature: 6 days
 Refrigerated: 7 days
 Frozen: 28 days

Reject Criteria
Hemolysis • Anticoagulants other than heparin

Includes
Iron, Total
Iron Binding Capacity
% Saturation (calculated)

Patient Preparation
Samples should be taken in the morning from patients in a fasting state, since iron values decrease by 30% during the course of the day and there can be significant interference from lipemia.

Methodology
Spectrophotometry (SP)

Reference Range(s)
Iron, Total

Age    Male
(mcg/dL)    Female
(mcg/dL)
<1 Month    32-112    29-127
1-11 Months    27-109    25-126
1-3 Years    29-91    25-101
4-19 Years    27-164    27-164
20-29 Years    50-195    40-190
30-49 Years    50-180    40-190
≥50 Years    50-180    45-160
Iron Binding Capacity

Age    Male
mcg/dL (calc)    Female
mcg/dL (calc)
<1 Month    94-232    94-236
1-5 Months    116-322    89-311
6-11 Months    176-384    138-365
1-19 Years    271-448    271-448
≥20 Years    250-425    250-450
% Saturation

Age    Male
% (calc)    Female
% (calc)
<1 Year    10-48    12-45
1-12 Years    12-48    13-45
13-19 Years    16-48    15-45
≥20 Years    20-48    16-45