cerebral amyloid angiopathy (CAA) related inflammation; cerebral amyloid angiopathy (CAA) related inflammation; This literature-non-study case was reported in a literature article and describes the occurrence of CEREBRAL AMYLOID ANGIOPATHY (cerebral amyloid angiopathy (CAA) related inflammation) and INFLAMMATION (cerebral amyloid angiopathy (CAA) related inflammation) in a 57-year-old female patient who received mRNA-1273 (Spikevax) for COVID-19 prophylaxis.        The patient's past medical history included Immune thrombocytopenic purpura (in childhood). Concurrent medical conditions included Cutaneous T-cell lymphoma (status post multiple local resections that is in remission.).  On an unknown date, the patient received first dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form. On an unknown date, the patient experienced CEREBRAL AMYLOID ANGIOPATHY (cerebral amyloid angiopathy (CAA) related inflammation) (seriousness criteria hospitalization and medically significant) and INFLAMMATION (cerebral amyloid angiopathy (CAA) related inflammation) (seriousness criteria hospitalization and medically significant). The patient was treated with PREDNISONE for Temporal arteritis, at a dose of decrease by 20 mg every 3 days until off; PREDNISONE for Temporal arteritis, at a dose of 80 milligram once a day and METHYLPREDNISOLONE (intravenous) at a dose of 1 gram. At the time of the report, CEREBRAL AMYLOID ANGIOPATHY (cerebral amyloid angiopathy (CAA) related inflammation) and INFLAMMATION (cerebral amyloid angiopathy (CAA) related inflammation) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Biopsy brain: negative for T-cell lymphoma, positive for meningothelial hyperplasia, and vascular amyloid beta deposits. There was no perivascular or destructive vasculitis with the vessels positive for amyloid beta deposits observed in the pathology. On an unknown date, CSF test: unremarkable CSF analyses and unremarkable CSF analyses. On an unknown date, Cytology: Negative. On an unknown date, Flow cytometry: Negative. On an unknown date, Lumbar puncture: 0 per microlitre white cells (first time) and 6 per microlitre white cells with 100% lymphocytes(second time). On an unknown date, Magnetic resonance imaging head: with and without contrast showed leptomeningeal enhancement and sulcal edema more prominent on the right and also had a cortical microhemorrhage in the right hemisphere. On an unknown date, Neurological examination: were normal without focal neurological deficits. On an unknown date, Protein total: 40 mg/dl and 47 mg/dl.     The action taken with mRNA-1273 (Spikevax) (Unknown) was unknown.   For mRNA-1273 (Spikevax) (Unknown), the reporter did not provide any causality assessments.   No concomitant medications were reported.  Patient presented with unilateral migraine headaches, dizziness, unsteadiness, and fogginess 36 hours after administration of mRNA vaccine against SARS-CoV-2. Patient was admitted for a 3-week history of new-onset headaches. The headaches started within 36 hours after the first dose of the Moderna SARS-CoV2 vaccine. Before the presentation to the hospital, patient went to an urgent care clinic with personal concerns for temporal arteritis and took one tablet of 20 mg prednisone which briefly alleviated her headaches. The patient then reported several episodes of numbness that started in the left finger that progressed to the arm and then the left leg lasting several minutes.   Gross examination results were normal. The patient did not have persistent weakness, numbness, tingling, dysarthria, gait disturbance, fever, chills or weight loss.  Cerebral amyloid angiopathy related inflammation (CAA-RI) is a neuroinflammatory disease that is associated with perivascular amyloidde position.  Authors reviewed the clinical literature of CAA-RI and its potential association with amyloid related imaging abnormalities (ARIA) after administration of immunotherapy against amyloid.  Company Comment: This literature non-study case concerns a 57 year old female patient with medical history of immune thrombocytopenic purpura in childhood and cutaneous T-cell lymphoma status post multiple local resections, in remission, who experienced the unexpected serious (hospitalization, medically significant) events of Cerebral amyloid angiopathy and Inflammation (cerebral amyloid angiopathy (CAA) related inflammation), 36 hours after receiving the first dose of mRNA-1273 vaccine. Patient was admitted to hospital for a 3-week history of new-onset headaches. The headaches started within 36 hours after the first dose of the mRNA-1273 vaccine. The key headache features included right temporal throbbing sensation associated with scintillating scotomas in the right eye, dizziness, unsteadiness and fogginess. Before her presentation to the hospital, she went to an urgent care clinic for temporal arteritis and took one tablet of 20 mg prednisone which briefly alleviated her headaches. She then reported several episodes of numbness that started in the left finger that progressed to the arm and then the left leg lasting several minutes. Gross and neurological examination were normal without focal neurological deficits. MRI head with and without contrast showed leptomeningeal enhancement and sulcal edema more prominent on the right. She also had a cortical microhemorrhage in the right hemisphere. After two relatively unremarkable CSF analyses, she underwent a brain biopsy which showed amyloid deposits in vessels instead of lymphomatous infiltration. Clinical diagnosis of cerebral amyloid angiopathy (CAA) related inflammation (CAA-RI) with amyloid spells was made, and she was treated with high dose steroids (1 g intravenous methylprednisolone with a prednisone taper; 80 mg for 10 days, then decrease by 20 mg every 3 days until off) with subsequent resolution of her headaches and cognitive symptoms. The benefit-risk relationship of mRNA-1273 is not affected by this report.   Most recent FOLLOW-UP information incorporated above includes: On 06-Apr-2023: Live follow-up received by safety on 06-Apr-2023 has Email with Agency received and contains significant information. Reporter information, Literature information, Lab data, Medical History, Product information, Event information and and Seriousness criteria were updated to Hospitalization.; Sender's Comments: This literature non-study case concerns a 57 year old female patient with medical history of immune thrombocytopenic purpura in childhood and cutaneous T-cell lymphoma status post multiple local resections, in remission, who experienced the unexpected serious (hospitalization, medically significant) events of Cerebral amyloid angiopathy and Inflammation (cerebral amyloid angiopathy (CAA) related inflammation), 36 hours after receiving the first dose of mRNA-1273 vaccine. Patient was admitted to hospital for a 3-week history of new-onset headaches. The headaches started within 36 hours after the first dose of the mRNA-1273 vaccine. The key headache features included right temporal throbbing sensation associated with scintillating scotomas in the right eye, dizziness, unsteadiness and fogginess. Before her presentation to the hospital, she went to an urgent care clinic for temporal arteritis and took one tablet of 20 mg prednisone which briefly alleviated her headaches. She then reported several episodes of numbness that started in the left finger that progressed to the arm and then the left leg lasting several minutes. Gross and neurological examination were normal without focal neurological deficits. MRI head with and without contrast showed leptomeningeal enhancement and sulcal edema more prominent on the right. She also had a cortical microhemorrhage in the right hemisphere. After two relatively unremarkable CSF analyses, she underwent a brain biopsy which showed amyloid deposits in vessels instead of lymphomatous infiltration. Clinical diagnosis of cerebral amyloid angiopathy (CAA) related inflammation (CAA-RI) with amyloid spells was made, and she was treated with high dose steroids (1 g intravenous methylprednisolone with a prednisone taper; 80 mg for 10 days, then decrease by 20 mg every 3 days until off) with subsequent resolution of her headaches and cognitive symptoms. The benefit-risk relationship of mRNA-1273 is not affected by this report.