PMC6606769_01
T1-weighted brain MRI showing interhemispheric leptomeningeal Gd+ enhancement before (A) and after (B) treatment with high dose steroids, Methotrexate and Rituximab. On gross inspection meninges appear severely inflamed (C) and pathological examination reveals massive meningeal granulomatous inflammation (D) with pre-dominant CD138 positive plasma cells (E), but also CD3 positive T cells (F). Massive infiltration with CD68 positive histiocytes with rheumatic granuloma formation was also seen (G).
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F1
This showed patchy interhemispheric pachy- and leptomenigeal enhancement adjacent to the parietal- and occipital lobes (Figure 1A). Subsequent, biopsy of meninges (Figure 1C) confirmed chronic inflammation dominated by CD138 positive plasma cells and a limited number of CD3 positive T-lymphocytes with limited infiltration into the underlying gray matter (Figures 1E,F). Additionally, granulomatous inflammation with dense infiltration of CD68+ histiocytes and the presence of rheumatoid nodules were found (Figures 1D,G). A 6 month follow-up MRI showed regression of meningeal enhancement (Figure 1B) and follow-up FDG-PET CT showed almost complete regression of pulmonary findings.