Systemic Serum Sickness
- Manifests throughout the body.
- Serum sickness can be induced by older vaccines that used antibodies from other species, such as horses and rabbits; though rare, it can also occur after transfusions. Anti-venom reactions can occur when, for example, anti-snake venom treatment is administered to a previously sensitized individual. Newer anti-venom treatments avoid this reaction.
- Graphically:
— X-axis = "Time in Days"; Y-axis = "Plasma levels"
— At time 0, show that plasma levels of foreign proteins spike immediately after administration, then slowly decline for a period; Initially, plasma antibody concentration is low.
— Then, show that as production of plasma antibodies increases, immune complexes are formed; thus, the concentration of foreign protein is rapidly reduced.
— Furthermore, show that the appearance of serum sickness symptoms coincides with immune complex formation, and typically resolve on their own.
- Common manifestations of serum sickness include: blotchy skin rashes, joint pain, peripheral edema, and fever.
Serum Sickness is an example of a Hypersensitivity Type II reaction:
Pathogenesis of immune complex-mediated hypersensitivity:
- Immune complexes become deposited on the vessel wall (or, in some cases, in the tissues).
- As a result, complement and neutrophil activation occurs, leading to the release of pro-inflammatory cytokines, enzymes, and reactive oxygen species.
- Increased vessel permeability allows the inflammatory molecules to cause additional tissue damage outside of the vessel.