IgG4-related disease presenting with profound bilateral orbital and adnexal inflammation.

Purpose: IgG4-related disease is an immune-mediated fibroinflammatory condition that can affect almost every major organ system. Orbital and adnexal involvement in IgG4-related disease though not uncommon can be varied depending on the site of the lymphoplasmacytic infiltration. This case of profound bilateral orbital inflammation is presented to demonstrate the significant clinical manifestations of IgG4-related ophthalmic disease. Observations: A 52-year-old man with a remote and seemingly unrelated history of lymphadenopathy presented to the Oculoplastics clinic with massive bilateral upper and lower lid swelling and induration. Hematologic testing demonstrated an elevation in serum IgG4 - a non-specific finding seen in various infectious, inflammatory, and malignant processes. Imaging demonstrated diffuse enlargement of orbital structures, including the lacrimal glands and extraocular muscles, as well as inflammatory changes of the adnexal and retrobulbar soft tissue. Orbital biopsy was required to confirm the diagnosis of IgG4-related ophthalmic disease. Conclusions and Importance: IgG4-related ophthalmic disease presents with various non-specific clinical signs and symptoms. The most common presentations include dacryoadenitis, enlarged orbital nerves, and orbital fat involvement; however, the extent of involvement both locally and systemically varies greatly. Clinical findings and imaging are helpful in narrowing the differential diagnosis; however, biopsy for histopathologic examination is essential to confirm IgG4-related disease. Physicians must maintain a high level of suspicion for the disease for proper management.