[Hyper-IgE in internal medicine]

Hyper-IgE may be found under many pathological conditions. The role of IgE is essentially associated with the occurrence of allergic manifestations, which may be accompanied by an increase of their serum levels. Elevation of total IgE has also been reported in association with certain rare genetic immune deficiencies called hyper-IgE syndromes. Other circumstances such as infectious diseases, tumors or autoimmune diseases may also be accompanied by an excessive synthesis of IgE. Considering the diversity of these situations, discussion of the prognostic value of total IgE is useful to the internist.