Severe Vision Loss with Optic Atrophy from IgG4-Related Hypertrophic Pachymeningitis with Steroid-Sparing Response to Rituximab

IgG4-related disease is a multisystem condition originally described in the context of autoimmune pancreatitis which can have neuro-ophthalmologic manifestations. These include hypertrophic pachymeningitis, hypophysitis, and orbital inflammation. Hypertrophic pachymeningitis can occur in the context of multiple conditions, infectious and inflammatory, and can result in severe vision loss when it involves the optic nerves.