Background/Purpose:

Inflammatory meningeal involvement can be idiopathic or associated with a variety of inflammatory rheumatic diseases such as ANCA associated vasculitis (AAV), rheumatoid (RA) arthritis, sarcoidosis or the recently described IgG4 related diseases.  Clinical symptoms can include headache, cranial neuropathies, cognitive changes, seizures, and encephalopathy.  Case reports have described successful therapy with steroids, methotrexate, mycophenolate, cyclophosphamide, and rituximab.  We present five cases of inflammatory meningitis unresponsive to various doses of steroids and other immunosuppressive agents treated successfully with rituximab.

Methods:

All 5 patients with inflammatory meningeal disease seen in rheumatology clinic over the last 5 years and treated with rituximab were reviewed.

Results: The current series consisted of 3 women and 2 men with an age range of 49-84 years.  Underlying diseases included 3 patients with AAV (1 localized AAV the other 2 with systemic AAV), 1 patient with RA, and 1 patient with idiopathic disease (possible GCA).  Major symptoms and signs included headaches in 4, hearing loss in 2, vision loss in 2, and significant cognitive changes in 2 patients.  MRI showed pachymeningeal thickening/enhancement in 4 patients and leptomeningeal in 1.  Four of the 5 patients had meningeal biopsies and all showed granulomatous inflammation, a finding not seen with IgG4 disease.  All patients had received steroids.  Other immunosuppressants used included methotrexate, azathioprine, leflunomide, mycophenolate, and abatacept.  

Rituximab was used due to continued meningeal symptoms and because it was indicated for the underlying diseases (AAV, RA).  The initial rituximab doses were 1000-2000 mg repeated every 6 months.  Two patients continued on methotrexate in addition to rituximab.  Three of 5 patients had rapid and dramatic reversal of most if not all of the symptoms referable to the meningeal inflammation.  One patient with localized GPA has significant improvement allowing the reduction of prednisone from 40-60 mg/day to 5 mg per day.  One patient had improvement without resolution of headache and hearing loss but has received only 1 dose.  Repeat MRI scans were available on 4 patients and results ranged from complete resolution of MRI changes in 1 patient and improvement in 3.  In 1 patient with the shortest treatment course, no MRI improvement has been noted to date.  No side effects occurred that are referable to rituximab treatment.

Conclusion: Rituximab is a useful agent in the treatment of refractory inflammatory meningeal disease whether idiopathic or associated with another inflammatory rheumatologic illness

ACR Meeting Abstracts - https://acrabstracts.org/abstract/inflammatory-meningeal-involvement-in-patients-with-rheumatic-diseases-responsive-to-rituximab/