IgE (summary and causes of increased and reduced levels)

Last reviewed 11/2023

IgE is found mainly in submucosal tissues where it is bound to mast cells and basophils.

The bridging of IgE molecules by antigen stimulates mast cell degranulation, and it is through this mechanism that IgE plays a role in the pathogenesis of immediate allergic anaphylactic reactions.

Causes of increased IgE levels include:

  • atopic diseases e.g. asthma, hay fever, eczema
  • parasitic diseases e.g. ascariasis, visceral larva migrans, hookworm disease, Echnococcus infection, schistosomiasis
  • E-myloma

Causes of reduced IgE levels include:

  • heriditary deficiencies
  • acquired deficiencies
  • ataxia-telangiectasia
  • non-IgE myeloma