[Case of EGPA and Eosinophilic Chronic Rhinosinusitis Concomitant with IgG4 Related Disease].

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis in patients with bronchial asthma and eosinophilic rhinosinusitis. Serum IgG4 levels are markedly elevated in patients with active EGPA, a disease which has been closely associated with IgG4-related disease (IgG4RD). A 68-year-old male with a history of asthma and eosinophilic rhinosinusitis developed vasculitis and orbital symptoms. The results of a laboratory examination showed eosinophilia (4,067/μl; 39%), while image evaluations revealed hypertrophy of the rectus muscles, trigeminal nerve, lachrymal gland, and bilateral submandibular glands. Biopsy of the paranasal sinus showed the prominent infiltration of eosinophils and IgG4-positive plasma cells. The patient was diagnosed with EGPA concomitant with IgG4RD and treated with systemic steroids. Although concomitant cases of EGPA with IgG4RD are extremely rare, clinical manifestations associated with both diseases are sometimes mixed. Therefore, systemic scrutiny may be required for cases of EGPA with high serum IgG4 levels and pathognomonic symptoms or findings of IgG4RD