IgE response in multiple myeloma.

IgE levels in sera of patients with multiple myeloma (MM) were found to be similar to those of patients with monoclonal gammopathy of unknown significance (MGUS) and to normal controls. This is in contrast to the significant depression in the level of the other polyclonal isotypes in patients with MM. Immediate skin test response to common environmental allergens was also preserved in patients with MM as compared with normal nonatopic controls. One-year treatment of MM patients with alkylating agents caused a significant decrease in the monoclonal immunoglobulin level and induced a tendency toward decreasing IgE level but had no effect on the polyclonal immunoglobulin concentrations. These findings suggest that IgE production and immediate skin test response is not impaired by the pathologic process in MM patients, in contrast to the production of other polyclonal immunoglobulins. This demonstrates the dissociation between the response of the IgE antibody and the other isotypes.