set of disorders that arise from an over-reaction of the immune system to an antigen's presence
- ex. of hypersensitivity reaction.
- -a process that begins with entry of an antigen into body; could be a diverse chemicals.
anaphylactic shock, the process...
- immune system response to antigen and B cells revert to plasma cells, (IgE produced); antibody fixes itself to surface of mfast cells (connective tissue cell) and white blood cell (basophils)
- -molecules of IgE attach to thousands of mast cells and basophils and person becomes highly sensitve to antigen
first priorities of treatment to anaphylaxis.
epinphrine, antihistamines, and smooth muscle relaxers
vast majority of reacdtions accompanied by limited production of IgE antibodies and sensitization in localized areas of body
- form of hypersensitivity rxn/immune system disorders
- -cell-damaging rxn that occurs when IgG antibodies react with antigens on surfaces of body cells. complement system often activated, and IgM antibodies may be involved.
immune complex hypersensitivity
- third form of hypersensitivity rxn.
- when IgG antibodies combine excessively with antigens dissolved in body fluids
- -immune complexes(many antigen-antibody rxn) accumulate along blood vessels or on tissues surfaces.
- final immune disorder.
- exaggeration of process of cell-mediated immunity.
- delayed reaction, seen til 24-72 hrs laterr.
- accumulation of T cells in skin and overactivity of cells against offending antigen. T cells begin attack body cell, drying of skin, with reddening and scaling
example of immune complex hypersensitivity.
butterfly rash, systemic lupus erythematosus (SLE)
example of cytotoxic hypersensitivity
transfusion reaction arising from mixing of incompatible blood types