Elderly man presenting with focal seizures, encephalopathy and tumefactive lesion on imaging scans

An 84-year-old man with cardiomyopathy and a pacemaker was admitted to our hospital due to a focal impaired awareness seizure. Computed tomography (CT) scan on admittance evidenced right parieto-occipital hypodensity with mild mass effect. A non-contrast CT scan realized in an outer institution seven months earlier showed that such hypodensity, considered then as a stroke, was present, but slowly progressing. He was submitted to therapy with phenytoin upon entry and his electroencephalogram showed increased slow-wave activity. Cerebrospinal fluid showed hyperproteinrachia, normal cell count and slightly reduced glycorrhachia. With such findings, the main hypothesis of neoplasm and neuroinfection emerged. Magnetic resonance imaging (MRI) could not be realized at first due to his pacemaker. Empiric treatment with acyclovir was initiated but, in spite of that, he maintained somnolence and left hemiparesis. The cardiology team was activated, and his pacemaker was set to do an MRI. His scan evidenced a T2/FLAIR hyperintense mass lesion on the right parieto-occipital area. SWI sequences showed microbleeds along the cerebral cortex and chronic lobar hematoma simulating cortical superficial siderosis. Hence, Cerebral Amyloid AngiopathyRelated Inflammation (CAA-ri) was diagnosed and pulse therapy with methylprednisolone was indicated. By closure of this report, he was started on antibiotics for urinary tract infection, and would be initiated on corticosteroids after 48 hours. CAA-ri is a rare yet reversible etiology of seizures, encephalopathy and focal neurological signs in patients with amyloid angiopathy, an entity that occurs mainly in the elderly as a deposit of amyloid protein on vessel walls. MRI is essential as it shows characteristic cortical-subcortical hemorrhagic lesions. Suggestive findings allows treatment with corticosteroids, optimizing neurological recovery and minimizing future deficits.