Presentation
Elderly male with controlled seropositive rheumatoid arthritis presented with subacute fluctuating confusion, apathy, word-finding difficulty, right-sided weakness and gait imbalance, and eventually focal seizures.
Patient Data
Leptomeningeal and dural enhancement over both upper frontoparietal convexities, especially on the right side. These are associated with sulcal hyperintensity and subtle cortical signal abnormality in the FLAIR sequences, in the upper frontal lobes, near the vertex.
Additionally, there is a mild increase in the degree of diffusion restriction on DWI of both upper frontoparietal convexities, especially in the right side. The findings were suggestive of meningoencephalitis.
The patient was thoroughly investigated including but not limited to: CSF analysis and culture, QuantiFERON-TB testing for Mycobacterium tuberculosis, serologies for human immunodeficiency virus and anti-onconeural antibodies, all of which were unremarkable. CT chest was unremarkable for sarcoidosis, and PET scan did not show evidence of underlying malignancy.
His clinical situation continued to deteriorate and developed acute asymmetrical parkinsonism of the right hemibody. Eventually, a leptomeningeal biopsy confirmed histopathologically findings of leptomeningeal involvement of a nodular rheumatoid meningitis subtype and was started on immunosuppressive therapy.
Status post small left frontal craniectomy. Expected postsurgical changes with linear enhancement lining the inner aspect of the craniectomy site.
Marked improvement in comparison with previous. There has been resolution of the dural and leptomeningeal enhancement over both frontoparietal convexities as well as resolution of the previously noted diffusion restriction.
Case Discussion
Despite the impressive improvement on MRI, the patient did not fully recover and suffered from ongoing cognitive and behavioral abnormalities.
Rheumatoid meningitis is known to have high morbidity and mortality. Early radiological and clinical recognition of the condition can expedite the initiation of immunosuppressive therapy, improving outcome.