Ferritin, Iron, TBIC, and calculated Transferrin Saturation

Iron, TIBC and Ferritin Panel -

This serum iron study panel may help diagnose iron deficiency or overload. Because ferritin level can be affected by clinical conditions other than iron disorders, the measurement of transferrin saturation-calculated from serum iron level and total iron binding capacity (TIBC)-in the same serum specimen may facilitate the diagnosis of iron deficiency or overload [1-3].

Serum ferritin level generally reflects body iron storage and can be used in the diagnosis of iron deficiency and overload. Transferrin saturation is the percentage of iron bound to transferrin. In patients with anemia, ferritin levels are most frequently used to determine whether iron deficiency is the cause [1]. However, as an acute phase protein, ferritin levels can be increased independently of iron status in inflammatory conditions, kidney disease, liver disease, and malignancy. In these clinical scenarios, the combination of ferritin level with other tests, such as transferrin saturation, may aid in the evaluation of iron deficiency [1,3].

In patients with suspected hemochromatosis, transferrin saturation and serum ferritin may be included in the initial evaluation of iron overload [2]. The combination of a transferrin saturation under 45% and a normal serum ferritin level may help exclude iron overload. A transferrin saturation equal or over 45% alone or with an elevated ferritin level may suggest further testing. Serum ferritin level is also a predictor of advanced fibrosis [2].

Note that reference intervals of serum iron, TIBC, transferrin saturation, and ferritin depend upon age and sex.

The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.