What calculation is used to determine the percentage saturation of transferrin?

• A. Serum iron / Ferritin x 100
• B. Serum iron / TIBC x 100
• C. TIBC / Ferritin x 100
• D. TIBC / Serum vitamin D x 100

Answer: (B)

The percentage saturation of transferrin is determined by calculating the serum iron divided by the total iron-binding capacity (TIBC) and then multiplying by 100. This calculation is important because transferrin is the primary protein that binds iron in the bloodstream, and its saturation can indicate various conditions related to iron metabolism.

In this context, TIBC represents the maximum amount of iron that can be bound by transferrin. By dividing the serum iron level by TIBC, healthcare providers can assess how much of the transferrin is actually bound to iron. When this quotient is multiplied by 100, it provides a percentage that reflects how saturated transferrin is with iron.

Understanding transferrin saturation is clinically significant because it helps in diagnosing conditions such as iron deficiency anemia or iron overload disorders. A low saturation percentage suggests iron deficiency, while a high percentage may indicate excess iron or conditions like hemochromatosis.

Other options do not correctly represent the calculation of transferrin saturation and involve values or ratios that are not relevant for this specific purpose.