Iron Test

Iron tests are usually advised when symptoms of low iron are seen in patients. In the early stages of deficiency, symptoms are usually not seen, and iron reserves may be significantly low before the signs and symptoms appear. Decreased levels of iron may be seen in conditions such as anaemia, blood loss, burns, cancer, infection, inflammation, myocardial infarction and nephrosis.

The symptoms of low iron are

• Fatigue
• Weakness
• Dizziness
• Headaches
• Pallor

Iron accumulation in blood and tissues is indicated by abnormally high levels in conditions, such as

• Joint pain
• Fatigue
• Abdominal pain
• Damage in organs, such as the heart and/or liver

High iron levels occur due to conditions, such as acute liver damage, aplastic anaemia, haemochromatosis, haemolytic anaemia, hemosiderosis, lead poisoning, nephritis and polycythaemia.

The patient should avoid all solid foods 12 hours before the test. Any intake of food may interfere with test results; however, water is allowed. No iron supplements should be taken by the patient 24-48 hours before the test.

An early morning blood sample is preferred, and it is taken from the patient’s arm. A volume of 5-10 mL is sufficient for the test. The whole test takes about 5 minutes. Possible but infrequent complications can be pain, light-headedness, bruising and local infection in the arm.

Laboratory levels of transferrin, iron and TIBC together provide the differential diagnosis of diseases, such as anaemia and assessment of iron-deficiency anaemia and helps evaluate thalassaemia, sideroblastic anaemia and hemochromatosis.

Normal results

• Iron:
  • Adult men: 65-175 micrograms/decilitre (μg/dL) or 11.6-31.3 micromoles/litre (μmol/L)
  • Adult women: 50-170 μg/dL or 9.0-30.4 μmol/L
  • Children: 50-120 μg/dL or 9.0-21.5 μmol/L
  • Newborns: 100-250 μg/dL or 17.9-44.8 μmol/L
• TIBC:
  • Men: 250-450 μg/dL or 44.8-76.1 μmol/L
  • Women: 250-450 μg/dL or 44.8-76.1 μmol/L
• Transferrin:
  • Adults: 250-425 mg/dL or 2.5-4.2 g/L
  • Children: 203-360 mg/dL or 2.0-3.6 g/L
  • Newborns: 130-275 mg/dL or 1.3-2.7 g/L
• Transferrin (iron) saturation:
  • Men: 10-50%
  • Women: 15-50%

Abnormal results

Increased transferrin is observed in iron-deficiency anaemia, pregnancy and oestrogen therapy.

Decreased transferrin is found in microcytic anaemia associated with chronic disease, protein deficiency, loss from burns, malnutrition, chronic infection, acute liver disease, renal disease (nephrosis), genetic deficiency, hereditary atransferrinemia and hemochromatosis.

Decreased iron occurs in iron-deficiency anaemia, chronic blood loss, chronic diseases (eg, lupus, rheumatoid arthritis and chronic infections), pregnancy and progesterone birth control pills and inadequate iron absorption.

Increased iron occurs in haemolytic anaemia, thalassaemia, acute iron poisoning, iron overload and its syndromes, hemochromatosis, multiple transfusions, intramuscular iron, acute hepatitis, and liver damage.

Increased TIBC is found in iron deficiency, pregnancy, blood loss and hepatitis.

Decreased TIBC is observed in hypoproteinaemia, hemochromatosis, non–iron-deficiency anaemia, liver cirrhosis, nephrosis, thalassemia and hyperthyroidism.

The iron saturation index is increased in hemochromatosis, increased iron intake, thalassaemia, hemosiderosis and acute liver disease

The iron saturation index is decreased in iron-deficiency anaemia, malignancy, anaemia of infection and chronic disease.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational perspective and is in no way a substitute for medical advice from a qualified doctor.