F4: FIBRINOLYTIC SYSTEM DISORDER

• fibrinolytic system comprises an inactive proenzyme, plasminogen, which can be converted to the active enzyme, plasmin, which in turn degrades fibrin into soluble fibrin degradation products.
• DISORDERS OF FIBRINOLYTIC SYSTEM


  The disorder can impair the breakdown of fibrin resulting in a build-up fibrin thus resulting to thrombosis.
• There are quantitative and functional abnormalities of plasminogen.
• • Functional and immunologic assays for plasminogen are available.
  • Assays for TPA and plasma plasminogen are now available in the clinical laboratory.
• PRIMARY FIBRINOLYSIS


  Excessive amounts of plasminogen activators from damaged cells/malignant cells
• SECONDARY FIBRINOLYSIS


  uncontrolled, inappropriate formation of fibrin within the blood vessels.

  Ex.

  o Infection

  o Neoplasm

  o Snake bite

  o HTR
• PLASMINOGEN DEFICIENCY TYPE I (TRUE PLASMINOGEN DEFICIENCY, HYPOPLASMINOGENEMIA)


  Proportionate decrease in both level of plasminogen and its activity

  
  

  CAUSE:

  • Congenital plasminogen deficiency is caused by mutations in the PLG gene.
  • This gene provides instructions for making a protein called plasminogen.
  • This condition is inherited in an autosomal recessive pattern.

  
  

  DIAGNOSIS:

  • Genetic Testing
  • Research studies
• PLASMINOGEN DEFICIENCY TYPE II (DYSPLASMINOGENEMIA) 


  • the level of immunoreactive plg = normal (or only slightly reduced)
  • whereas the specific functional plg activity is markedly reduced because of abnormalities in the variant plg molecule.