Steroid-resistant relapsing IgG4-related pachymeningitis treated with methotrexate.

IMPORTANCE: IgG4-related disease, which is newly recognized, is characterized by lymphoplasmacytic infiltration with increased IgG4-secreting plasma cells. Although a favorable response to steroids has previously been reported, the durations of follow-up to confirm the long-term benefits and clinical courses were limited. We describe long-term favorable response of oral methotrexate in a patient with IgG4-related pachymeningitis who was resistant to steroid therapy. OBSERVATIONS: A patient in his mid-60s with pathologically proven IgG4-related pachymeningitis who was resistant to steroid therapy and experienced an exacerbation of symptoms 4 times is described. Low-dose oral methotrexate induced significant clinical and radiological improvement, with sustained remission of the disease over 2 years without complications. CONCLUSIONS AND RELEVANCE: The long-term favorable response to oral methotrexate in the current patient suggests that methotrexate is a useful alternative treatment option in patients with IgG4-related pachymeningitis who are resistant to steroid therapy or who experience adverse effects from steroids.