Long-term efficacy of anti-IL-4 receptor antibody in a patient with aspirin-exacerbated respiratory disease and IgG4-related disease.

Background: Aspirin-exacerbated respiratory disease (AERD) and IgG4-related disease (IgG4RD) share a common pathway of Th2-mediated immune mechanism; there have been several cases of IgG4RD developed in patients with asthma, especially in those comorbid with chronic rhinosinusitis (CRS). IgG4RD has often been treated with systemic corticosteroids, rituximab, or immune-suppressive agents, but frequently failed with relapse.

Case presentation: Here, we present a case of a 64-year-old male patient with severe AERD with CRS complicated with IgG4RD, who has been successfully treated and maintained with anti-IL-4 receptor antibody, dupilumab after achieving unsatisfactory responses with previous treatments including steroids, rituximab, omalizumab, and reslizumab. The patient's symptoms (periorbital swelling and asthmatic/nasal symptoms) were remarkably improved; serum levels of IgG4/IgE as well as plasmablast/eosinophil counts progressively decreased without any recurrence sign for over 2 years of dupilumab treatment.

Conclusion: These findings demonstrate that blocking the IL-4/IL-13 pathway with dupilumab can be an effective treatment with long-term safety in patients with severe AERD with CRS complicated by IgG4RD.