ABSTRACT Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition characterized by tumefactive lesions, lymphoplasmacytic infiltration, and fibrosis. Orbital involvement is uncommon in children and may mimic infectious dacryoadenitis, idiopathic orbital inflammation, and lymphoproliferative disorders. We report the case of a 13-year-old girl with four days of left periorbital swelling and pain, associated with lacrimal gland enlargement on imaging. Biopsy showed fibrosis, dense lymphoplasmacytic infiltration, and reactive lymphoid aggregates. Immunohistochemistry demonstrated mixed B- and T-cell populations, polyclonal kappa/lambda plasma cells, […]
