Rapidly Progressive Contralateral Internal Carotid Artery Stenosis After COVID-19 Infection in a Down Syndrome Patient With Unilateral Moyamoya Arteriopathy

Moyamoya arteriopathy is a condition where chronic, progressive stenosis of large intracranial arteries, primarily of the anterior circulation, results in ischemia and the growth of small, abnormal collateral vessels. There is increasing evidence that infectious pathologies, such as COVID-19, may serve as a sort of trigger, or "second hit," for the development of moyamoya arteriopathy. In this article, we present the case of a 13-year-old female with Down syndrome and unilateral moyamoya arteriopathy who developed contralateral internal carotid artery (ICA) dissection and thrombus in the setting of a positive COVID-19 test and subsequently developed rapidly progressive contralateral ICA and bilateral anterior cerebral artery (ACA) moyamoya-like stenosis. The rapidly progressive contralateral ICA and bilateral ACA moyamoya-like stenosis are likely multifactorial in nature. The contralateral ICA may have had a predisposition for injury and stenosis due to the preexisting moyamoya arteriopathy, making stenosis more likely after COVID-19-induced vascular inflammation and injury as well as after a possible thrombectomy-associated injury. Based on this presentation, patients with moyamoya arteriopathy may be at risk for rapid progression of their moyamoya pathology when exposed to catalysts, including infection, such as COVID-19, and vascular injury, such as thrombectomy-induced injury. In these circumstances, high suspicion and close monitoring are essential for addressing ischemia related to the stenosis before permanent injury.

Recurrent Headaches and Moyamoya Syndrome in a Non-Asian Descendant: A Case Report

Moyamoya disease (MMD) is a rare yet progressive cerebrovascular disorder caused by the constriction of arteries, which leads to the twisting and tangling of small arteries in the brain, ultimately causing blockages. Although moyamoya angiopathy (MMA) has been known for almost six decades, its pathophysiology remains unknown, posing challenges to timely diagnosis. Moyamoya syndrome (MMS) refers to the association of MMA with various diseases, including infections, tumors, arteriovenous malformations, radiation treatment, and hereditary disorders. On the other hand, MMD, an idiopathic form, is now more frequently linked to genetic abnormalities. MMS is more common in people of Asian descent, but we encountered and aim to discuss a rare case of a 32-year-old Caucasian from Colombia who was diagnosed with it. The patient initially presented with unexplained symptoms of stroke, prompting doctors to conduct additional imaging. Fortunately, this led to her timely diagnosis. The report discusses the challenges that healthcare professionals face in diagnosis when presented with such uncommon cases. Through this case report, we try to review the presentation, diagnosis, and treatment used for this patient with MMS. The limited information available about the disease, especially the demographic data in countries outside Asia, often leads to delayed diagnoses, emphasizing the need for further exploration. Timelier diagnosis and heightened research into the disease's presentation and risk factors could lead to improved outcomes. Our report also briefly discusses the effectiveness of the current treatment protocol for patients. Currently, the patient is undergoing rehabilitation and showing promising progress.