Serum Ferritin

**Semantic type:** Amino Acid, Peptide, or Protein

**Definition:** An iron-poor form of ferritin found in blood plasma or serum that is comprised almost exclusively of light subunits (FTL). The levels of this form of ferritin is a surrogate marker for systemic iron storage. Abnormal levels of serum ferritin are associated with iron storage-related disorders (anemia and hemochromatosis) and liver disease (hepatitis or cirrhosis).