Iron Panel Interpretation

[TimG]

Referencing Nightwalkers Spring 22 edition, "Ask the Doctor: column. Dr. Denise Sharon answered a question about RLS symptoms by suggesting Iron Stores testing, "including blood work for ferritin, transferrin saturation and iron-binding capacity".

I know about ferritin and RLS, but this is the first I've read about the role of transferrin sat and IBC. Does anyone know how to interpret these values related to RLS?

[badnights]

Unedited notes I've collected over the years:

Most of the body’s iron is contained in hemoglobin molecules within red blood cells. The rest is stored in the tissues as ferritin or hemosiderin, plus small amounts are used in other proteins and enzymes.
Blood consists of red blood cells (RBCs), white blood cells (WBCs), and platelets suspended in a fluid called plasma.
Serum is the clear part of blood that remains after the solid elements have been separated out.
Anemia = a condition in which blood has reduced ability to carry oxygen. Can be from lack of RBCs or lack of hemoglobin (the latter type can be from lack of iron).

µmol/L / 0.1791 = µg/dL

Serum iron — measures the total amount of iron in the liquid portion of the blood, i.e. the amount of iron that is in transit
• nearly all of this Fe is bound to transferrin.
• The amount of iron present in the blood will vary throughout the day and from day to day.
• NORMAL 60 to 170 µg/dL = 11 – 30 µmol/L
Transferrin—(above)
TIBC* (total iron-binding capacity)—measures the total amount of iron that could be bound by available proteins in the blood (which are primarily transferrin).
• an indirect measurement of the amount of transferrin in the blood that hasn’t been filled with iron i.e. that is available for binding iron
• expressed in terms of the amount of iron that could be bound if all the free sites were used.
• The measurement of TIBC actually requires assessment of the number of free sites (sites without bound iron) on all the transferrin in the plasma or serum; this is called the unsaturated iron binding capacity (UIBC). TIBC = UIBC + iron
• Though TIBC is related to the amount of transferrin, TIBC and transferrin are not synonymous
• NORMAL 240-450 µg/dL = 42 – 81 µmol/L
Transferrin saturation (%) = (Serum iron level x 100%) / TIBC
aka Saturation index = (Serum iron level) / TIBC
• an estimate of how many of transferrin iron-binding sites are occupied.
• Under normal conditions, transferrin is one-third saturated with iron, & two-thirds of its capacity is held in reserve.
• NORMAL %Sat = 25-35% aka NORMAL Sat Index = 0.25 – 0.35
• Purpose: to assess your body's ability to transport iron in the blood; to help diagnose iron-deficiency or iron overload.
Transferrin index = (Serum iron level x 100%) / transferrin concentration
• not common
Ferritin—the concentration of ferritin, a protein made by almost all cells in which to store iron. More iron in body = more ferritin is made by tissues.
• Purpose: To determine your body's total iron storage capacity; to help diagnose iron-deficiency or iron overload.
• Reflects the total body iron
• But it does not reflect low stores in some organs if there are high stores elsewhere. For example, the brain can be iron deficient while serum ferritin is normal.)
• It will be low when there is iron deficiency somewhere in the body, and high when there is an excess of iron in the body.
• Ferritin typically increases during any inflammatory process (chronic inflammation, infections, malignancies) i.e. ferritin is a positive acute phase reactant.
• Rises with age
• NORMAL (according to many): 12-300 ng/mL == 12-300 µg/L
• WED/RLS normal: >100
Complete blood count (CBC)—a group of tests that measure concentrations of various blood cells, including red blood cells (RBCs), white blood cells (WBCs), and platelets (PLTs).
Hematocrit—a test that measures the proportion of your blood that is made up of red blood cells (RBCs). The hematocrit is a ratio of the volume of red blood cells to the volume of all these components together, called whole blood. The value is expressed as a percentage or fraction.

In iron deficiency, all of the stored iron in the body has been used up. The body tries to compensate by producing more transferrin to increase iron transport. While the serum iron level continues to decrease, the transferrin level increases. Thus, the amount of transferrin available to bind iron (TIBC) increases and the amount of transferrin saturated with iron (i.e., percent transferrin saturation) decreases.

Plus there's a table which I attach as PDF

iron labs table.pdf

(17.9 KiB) Downloaded 151 times