Elevated serum IgG4 levels in cystic fibrosis patients

Abstract
The quantitative measurement of the IgG [immunoglobulin G] subclass composition of the sera from 16 patients with cystic fibrosis has revealed grossly elevated levels of IgG4 in 7 patients. The possible significance of this observation is discussed in relation to recent reports of a high incidence of immediate-type hypersensitivity in such patients.