Beyond the Lobar Hemorrhage: A Multimodality Diagnostic Journey to CerebralAmyloid Angiopathy-Related Inflammation

Cerebral amyloid angiopathy-related inflammation (CAA-ri) is an uncommon, potentially treatable inflammatory manifestation
of cerebral amyloid angiopathy that may mimic other pathologies including: infection, neoplasm, or primary CNS vasculitis. We
present a case of a 67-year-old male suffering from multiple myeloma and receiving pomalidomide who over the course of one
month developed symptoms of progressive right facial asymmetry, dysarthria, and intermittent fever. Laboratory evaluation
showed pancytopenia with severe neutropenia. Non-contrast CT demonstrated extensive asymmetric left hemispheric edema
without hemorrhage or midline shift. CT venography displayed a prominent left hemispheric deep vessel, but no venous
thrombosis, redirecting the investigation toward a primary cerebral pathology. MRI revealed extensive left hemispheric T2
hyperintensity, mild enhancement along the path of the Lentico striate artery with some restricted diffusion, and multiple
blooming paramagnetic foci above and below the tentorium, on susceptibility-weighted imaging.

The main differential diagnoses included: intravascular lymphoma, opportunistic fungal infection, and inflammatory
vasculopathy. Cerebrospinal fluid infectious studies, cultures, and autoimmune testing were all negative. Initial treatment with
Dexamethasone produced marked clinical and radiologic improvement; however, neurological symptoms recurred after steroid
withdrawal. Follow-up MRI demonstrated improvement of the cerebral edema but increased number of the susceptibility foci,
suggesting improvement of inflammation with persistent underlying small-vessel leakage supporting the diagnosis of CAA –ri .

The patient underwent cerebral biopsy. The diagnosis was angitis.

This case emphasizes the value of integrating CT, CT venography, and MRI with laboratory and clinical finding in the
diagnostic process of complex rare disease. In a patient with subacute neurological decline, asymmetric vasogenic edema,
enhancement and multiple foci of susceptibility lesions should raise suspicion for CAA-ri.

Understanding this inflammatory CAA spectrum is increasingly important. Anti-amyloid monoclonal antibody therapy expands.
Amyloid Related Imaging Abnormalities (ARIA) can present with edema and hemosiderin deposition.

Mentors: Dr. Shimon Maimon & Dr. Roni Shreter