Antagonistic Plasma Factors

Chemicals

  • Arsenic compounds
  • Drugs in excess
Animal Venom
  • Evidence on the blood film
  • intravascular haemolysis caused by neurotoxins and procoagulants triggering the coagulation pathway via Factor X

Coagulation Cascade
Disseminated intravascular coagulation forming "clotheslines" that hang up cells resulting in schistocytes and microspheroytes, indicators of intravascular haemolysis.
  • Look for haemoglobinuria, reticulocytes/Heinz bodies, serum bilirubin etc

  • Coagulation Profile

    • Prothrombin time - Inc. (Extrinsic p'way)
    • APTT - Inc. (Intrinsic p'way)
    • Platelet Count - Dec.
    • Thrombin Clotting Time - Inc. (lack of fibrinogen)
    • Fibrinogen - Dec.
    • D-dimer - due to fibrinolysis following coagulation
Infectious Agents
  • Clostridium perfringens
    • Secretes a phospholipiase destroying cell membranes - can result in severe intravascular haemolysis related to the extent of septacaemia.
  • Malaria
    • Extavascular haemolysis (due to protein secreted from the organisms coating other cells following exit fro mthe host RBC)
    • Intravascular haemolysis (due to the intracellular parasite itself)
Water
  • Intravascular haemolysis
  • Can result from irrigation due to certain procedures (e.g. prostatectomy) enetering the bloodstream
Plasma Lipid Abnormalities
  • Spur cells
  • Rare complication of liver disease
  • Excess cholesterol in membrane causing haemmolysis due to splenic sequestration
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