Generalised Type III Hypersensitivity Reactions (Serum Sickness)

SERUM SICKNESS

  • When large amounts of antigen enter blood and bind to antibody, circulating immune complexes are formed. If the antigen is in excess, small complexes form which are not cleared from the system.
  • They are deposited in the walls of blood vessels, especially medium sized arteries and in vessels where there is a physiological outflow of fluid such as gomeruli, synovia and the choroids plexus and can cause tissue damaging Type III reactions.
  • Such kind of reaction were observed in individuals administered with large doses of hyperimmune serum (eg: antitetanus serum) from a foreign species and is known as serum sickness.
  • The symptoms are generalized vasculitis with erythema, edema and urticaria of the skin, neutropenia, lymph node enlargement, joint swelling and proteinuria. The reaction is of short duration subsiding in a few days time.
Last modified: Thursday, 26 August 2010, 9:37 AM