EBM Consult

Lab Test: Ferritin Level

    Lab Test
    • Lab Test: Ferritin Level
    Description
    • Measurement of the body's major iron storage protein to evaluate the body's total iron stores, in uncomplicated iron deficiency states, iron overload states (i.e., hemochromatosis), and to monitor response to iron therapy. 
    • Most sensitive test to determine iron-deficiency anemia
    Reference Range
    • Adult males:  30-300 ng/mL (30-300 mcg/L) 
    • Adult females:  10-200 ng/mL (10-200 mcg/L)
    • Newborns:  25-200 ng/mL (25-200 mcg/L)
    • ≤ 1 month:  200-600 ng/mL
    • 2-5 months:  50-200 ng/mL
    • 6 months-15 years:  7-142 ng/mL
    Indications & Uses
    • Suspected acute respiratory distress syndrome (ARDS)- serum ferritin levels are significantly increased in patients at risk for ARDS and in established cases, as compared with healthy controls. 
    • Suspected adult-onset Still's disease (AOSD)- an increase in serum ferritin level may be suggestive of AOSD.  Ferritin levels >1,000 mcg/L in women and 1,500 mcg/L in men (five times the upper limit of normal) have been associated with AOSD.  In patients with inactive diseases, ferritin may have limited clinical utility. 
    • Suspected hemochromatosis - serum ferritin concentrations vary with age and sex; however values more than 2 standard deviations above the appropriate mean are considered abnormal.  The combination of an elevated ferritin value that is twice normal, and an elevated transferrin saturation (60% for men and 50% for women) is suggestive of iron overload. 
      • The diagnosis of hemochromatosis is based on several parameters:  an elevated serum ferritin level (≥200 mcg/L in premenopausal women and ≥300 mcg/L in men or postmenopausal women), a transferrin saturation of 55% or more, or evidence of liver disease. 
    • Suspected iron deficiency anemia - a ferritin level of ≤15 mcg/L is a marker of depleted or absent iron stores, and confirms iron deficiency anemia in the presence of low Hgb or HCT. 
      • As ferritin levels may be normal or increased in anemia of chronic disease, using a cutoff level of 30 mcg/L or less may be more accurate in detecting concomitant iron deficiency anemia.
      • The cutoff values for serum ferritin for the diagnosis of iron deficiency is 8 to 12 mcg/L (8 to 12 ng/mL) in children aged 1 to 5 years.
    • Suspected preterm labor - high third trimester maternal serum markers of ferritin are associated with preterm delivery and markers of maternal infection.  Statistically significant elevations are seen in serum ferritin levels of women who will develop preterm labor and delivery. 
      • High plasma ferritin levels, especially at 26 weeks, were strongly associated with subsequent preterm delivery and low birth weight in a study of black women.
    Clinical Application
    • The serum ferritin study is a good indicator of available iron stores in the body and thus is normally present in the serum in concentrations directly related to iron storage.  In normal patients, 1 ng/mL of serum ferritin corresponds to approximately 8 mg of stored iron.
    • Ferritin levels rise persistently in males and postmenopausal females.  In premenopausal females, levels stay about the same. 
    • Decreases in ferritin levels indicate a decrease in iron storage associated with iron-deficiency anemia.  A ferritin level of below 10 mg/100 mL is diagnostic of iron-deficiency anemia.  A decrease in serum ferritin level often precedes other signs of iron deficiency, such as decreased iron levels or changes in RBC size, color, and number. 
    • Increased levels are a sign of iron excess, as seen in hemochromatosis, hemosiderosis, iron poisoning, or recent blood transfusions
    • Increased levels may indicate:
      • Hemochromatosis, hemosiderosis, megaloblastic anemia, hemolytic anemia, alcoholic/inflammatory hepatocellular disease, inflammatory disease, advanced cancers, chronic illnesses such as leukemias, cirrhosis, chronic hepatitis, or collagen-vascular disease. 
    • Decreased levels may indicate:
      • Iron-deficiency anemia, severe protein deficiency, or hemodialysis.
    Related Tests
    • Iron level - a direct measurement of bound iron in the blood.
    • Total iron-binding capacity - TIBC is a measurement of all proteins available for binding mobile iron. 
    • Transferrin - transferrin represents the largest quantity of iron-binding proteins.
    • Transferrin receptor assay - used to differentiate iron deficiency from other anemias.
    Drug-Lab Interactions
    • Recent transfusion or recent ingestion of a meal containing a high iron content (red meats) may cause elevated ferritin levels.  The iron that is ingested stimulates ferritin production to store the increased serum iron.
    • Recent administration of a radionuclide can cause abnormal levels if testing is performed by radioimmunoassay.
    • Hemolytic disease may be associated with an artificially high iron content.  Ir on is freed from the hemoglobin that is released from the hemolyzed RBCs.  Ferritin synthesis is increased to store the increased serum iron.
    • Acute and chronic inflammatory conditions and Gaucher disease can falsely increase ferritin levels.
    • Disorders of excessive iron storage (e.g., hemochromatosis, hemosiderosis) are associated with high ferritin levels.  Ferritin synthesis is increased to store the increased serum iron.
    • Iron-deficient menstruating women may have decreased ferritin levels because their iron stores are generally low as a result of monthly menses.
    • Iron preparations may increase ferritin levels.  Ferritin synthesis is increased to store the increased serum iron.
    Test Tube Needed
    • Red or marbled top tube
    Procedure
    • Collect a venous blood sample. 
    • Avoid violent mixing which may denature ferritin. 
    • Apply pressure or a pressure dressing to the venipuncture site and assess the site for bleeding.
    Storage and Handling
    • Store sample for up to 7 days at 2°C to 8°C or for 6 months at -20°C.
    What To Tell Patient Before & After
    • Explain the procedure to the patient.
    • Tell the patient that some laboratories require fasting.
    References
    • Pagana K, Pagana TJ eds. Mosby's Manual of Diagnostic and Laboratory Tests. 5th Ed.  St. Louis, Missouri. 2014

MESH Terms & Keywords

  • Ferritin