SAT474 A Case Report Of Moyamoya Disease Associated With Uncontrolled Graves' Disease

Disclosure: Z. Tan: None. E. Briggie: None. M. Correia: None. Background: Moyamoya disease is an uncommon cerebrovascular disease that is featured by narrowing of large intracranial arteries and the development of prominent small-vessel collaterals. The etiology of Moyamoya disease is unknown, but it can be associated with multiple conditions including atherosclerosis, sickle cell disease, and Protein S deficiency. It is rarely associated with uncontrolled Graves’ disease. Clinical Case: A 37-year-old female with a history of Graves’ disease and type 1 diabetes presented with sudden onset of slurred speech and right-sided weakness. A CTA of the head and neck showed a small hypodensity in the left basal ganglia without corresponding perfusion deficit and narrowed left internal carotid arteries without focal stenosis. In addition, a brain MRI showed patchy infarcts in the left middle cerebral artery territory. A cervical and cerebral angiogram showed multiple areas of stenosis which was concerning for Moyamoya disease. She ultimately underwent balloon angioplasty of the left internal carotid artery with improvement in perfusion. During the workup for secondary causes of Moyamoya disease, her TSH was < 0.01 µIU/mL (0.270-4.20 µIU/mL), with elevated T4 at 3.84 ng/dl (0.80-1.80 ng/dl) and elevated TSI at 15.5 IU/L (< 0.54 IU/L). Importantly, she was diagnosed with Graves’ disease 2 years before admission, and this condition has never been well controlled due to poor compliance with methimazole. A TSH measured 5 months before admission was also undetectable with elevated T4 at 2.8 ng/dl. Her other workups for Moyamoya disease were negative including HIV antigen/antibody, syphilis IgG antibody, Lyme disease IgG & IgM antibodies, hepatitis panel antibodies, ANA, ANCA, free protein S, dsDNA antibody, factor 5 Leiden mutation, vascular endothelial growth factor-D and urine drug screening test. She started methimazole 20 mg daily and was discharged to acute rehabilitation. After rehabilitation, her Graves’ disease is slowly improving with most recent TSH < 0.008 µIU/mL and free T4 at 2.39 ng/dl. She is almost back to her baseline with significant improvement in speech and strength. Conclusion: Uncontrolled Graves’ disease should be considered in the differential diagnosis of Moyamoya disease in young subjects who present with stroke-like symptoms. Reference: Ischemic Stroke and Intraventricular Hemorrhage in Moyamoya Syndrome Associated With Graves' Disease: A Case Report. Neurologist 2022 Presentation Date: Saturday, June 17, 2023