Eosinophilic Granulomatosis with Polyangiitis Demonstrating IgE-immune Complexes and the Possible Involvement of IgE Autoantibodies

Abstract

We herein report a case of female eosinophilic granulomatosis with polyangiitis (EGPA) in which polyethylene glycol (PEG) precipitation was used to evaluate the patient's levels IgE-immune complexes (IC). Her serum IgE (7,110 IU/mL) and IgE-IC (1,880 IU/mL) levels were observed with an IgE PEG precipitated index of 26.4%. We speculate that the circulating IgE-IC were formed by anti-neutrophil IgE autoantibodies. Therefore, the large amount of IgE autoantibodies in the patient's serum appears to have induced a constant allergic pathology. This pathology may have resulted in a marked infiltration of eosinophils into the tissues, as well as intensified the EGPA pathology.