6393 Prolactinoma with Concomitant Moyamoya Disease

Abstract Disclosure: A.N. Davis: None. G. Elshimy: None. Introduction: Moyamoya disease is a cerebrovascular condition associated with stenosis of the intracranial internal carotid arteries and their proximal branches. Moyamoya is rare and has been reported to have an incidence of 0.086 cases per 100,000 persons. Only a few cases had reported concomitant prolactinoma with Moyamoya disease. We present a rare case of Moyamoya disease accompanied by a prolactin-secreting pituitary adenoma. Case: A 38-year-old female with history of prior CVA in 2019, 2022, and 2023 and prolactin-secreting pituitary macroadenoma diagnosed 2019 presented February 2023 to establish care in the Endocrine clinic for management of hyperprolactinemia. She reported history of hyperprolactinemia diagnosed 2019 and was treated with cabergoline in the past. She had CTA head January 2023 during admission for left sided weakness showing high-grade stenosis of the proximal M1 segment of the right MCA concerning for vasospasm versus occlusion with collateralization. Moreover, in January 2023 she had an angiogram performed demonstrating critical right MCA stenosis with Moyamoya changes with distal collaterals from the right ACA and PCA. When seen in clinic, she complained of galactorrhea with breast soreness and oligomenorrhea. Labs at this time were significant for prolactin level of 122.89ng/mL, estradiol 74pg/mL, LH 1.75mIU/mL, FSH 2.50mIU/mL. She was restarted on cabergoline 0.5mg twice weekly. Repeat prolactin level 8/16/23 was improved to 2.71ng/mL with improvement in her symptoms. Discussion: Moyamoya refers to the angiographic changes involving the occlusion of the arteries near the circle of Willis with arterial collateral development. Moyamoya disease refers to patients with Moyamoya findings potentially from a genetic predisposition, whereas Moyamoya syndrome refers to the presence of Moyamoya findings with associated medical conditions (history of radiation therapy, trauma, brain tumors, atherosclerosis, meningitis, hypercoagulability etc.) which may explain the occlusion. There have been several sellar and suprasellar masses reported in conjunction with Moyamoya disease including craniopharyngioma and other hormone-producing pituitary adenomas. It has been postulated that hypothalamic disturbances owing to reduced perfusion may lead to hyperprolactinemia via reduced downregulation of lactotrophs. Interestingly, our patient had unilateral rather than bilateral arterial stenosis which have been reported in other cases in the literature. Initial management is like other patients with prolactinomas and includes medical management with dopamine agonists. Conclusion: We report a rare case of Moyamoya disease with concomitant prolactinoma. This disease has been also reported with other hormone-producing pituitary adenomas and hypopituitarism. Hence, endocrinologists should be aware of these rare cases. Presentation: 6/1/2024