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Acute phase protein (Acute Phase Reactants)

Fibrinogen (Factor 1)



  1. For the evaluation of bleeding disorder.
  2. If there is excessive bruising.
  3. In case of bleeding from the gums and nose.
  4. In case of Bleeding in the GIT and blood in the stool.
  5. In case of blood in the urine.
  6. If there is rupture of the spleen.


  1. Avoid clot formation.
  2. Avoid collecting the blood from the heparinized blood vessel.
  3. Avoid contamination with tissue which contains tissue thromboplastin.
  4. Avoid contamination with heparin.


  1. This is beta-globulin and is usually absent from the serum.
  2. It is a fibrillary group of a protein.
  3. This consists of three pairs of polypeptide chains.

  1. This is synthesized in the liver.
  2. When fibrinogen is transfused:
    1. 50% disappears in 48 hours.
    2. 75% disappears in 6 days.
    3. Half-life is 3.5 to 4 days.


  1. This is an essential protein for blood clot formation.
  2. In the process of clotting, all the fibrinogen in the plasma is converted to fibrin.
    1. Now the serum will be laking fibrinogen.
  3. The fibrinogen has a major effect on the RBCs sedimentation rate by coating the cells.
    1. This allows the cells to settle (sediment) faster.
    2. So increased fibrinogen indicate raised ESR.
  4. Disseminated intravascular coagulopathy (DIC):

  1. This is raised by the inflammation or tissue injury.
  2. Snake venom leads to depletion of fibrinogen.

  1. An elevated level may be seen in:
    1. Acute infections.
    2. Myocardial infarction.
    3. Patients with malignancies.
    4. Inflammatory conditions like Rheumatoid arthritis and Glomerulonephritis.
    5. In the case of traumatic injury. 
    6. Patient with a stroke.
    7. In pregnancy.
    8. Person smoking cigarettes.
    9. Patients with peripheral artery disease.
  2. This is raised in acute and chronic inflammation.


The increased level is seen in:

  1. In trauma.
  2. In coronary heart disease.
  3. Acute inflammatory condition.
  4. In cigarettes smoking.
  5. Maybe increased in thrombosis.

The decreased level is seen in:

  1. In liver diseases.
  2. Congenital deficiency.
  3. In DIC (disseminated coagulopathy).
  4. In fibrinolysis.


  1. This is usually inherited as an autosomal recessive trait.
  2. The structure of fibrinogen is functionally defective.
  3. There may be bleeding episodes, bruise and poor healing of the wound.


  1. This leads to relatively mild hemorrhage.
  2. Few of these may have the tendency for thrombosis.

Value for the layman:

Possible References Used

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