1. Neurology Resident and Fellow Section
Cerebral Amyloid Angiopathy-Related Inflammation Presenting with Isolated Leptomeningitis
Teaching NeuroImages
Neurology
Resident and Fellow Section
© 2017 American Academy of Neurology

2. Vignette
A 69-year-old woman presented with one-month of rapid cognitive decline preceded by one year of very mild memory changes.
Kang et al.
© 2017 American Academy of Neurology

3. Imaging Kang et al. Figure 1. Magnetic resonance brain imaging.
T1-weighted images post-gadolinium (A) demonstrate leptomeningeal enhancement of the bilateral temporal, parietal, and occipital lobes (arrowheads), with associated non-suppression of sulcal cerebrospinal fluid (arrows) on fluid attenuated inversion recovery (B). No microhemorrhages or areas of restricted diffusion were seen on gradient-echo or diffusion weighted images (not shown).
Kang et al.
© 2017 American Academy of Neurology

4. Imaging
Figure 2.  A) Vascular amyloid deposition with perivascular inflammation but no overt angiitis.  Parenchyma  shows reactive gliosis.  B) Beta-amyloid immunostain demonstrating amyloid angiopathy (arrows) and plaque (arrowhead).  C) CD3 and CD68 immunostains show no definite angioinvasion by immune cells.
Kang et al.
© 2017 American Academy of Neurology

5. Cerebral Amyloid Angiopathy-Related Inflammation Presenting with Isolated Leptomeningitis
Examination showed impaired attention, logopenic aphasia, anosagnosia, simultagnosia, graphesthesia, and apraxia. Neuroimaging demonstrated leptomeningeal enhancement without significant parenchymal lesions or cerebral microbleeds (figure 1).
A lymphocytic pleocytosis (15 nucleated cells/μl) was noted on cerebrospinal fluid analysis.
Extensive diagnostic testing was inconclusive, including flow cytometry and cytology, conventional angiography, body computed tomography and positron emission tomography.
Cerebral amyloid angiopathy-related inflammation (CAA-RI) was confirmed on brain biopsy (figure 2).
CAA-RI rarely presents with isolated leptomeningeal enhancement and can be a challenging diagnosis (1, 2).
Kang et al.
© 2017 American Academy of Neurology