Familiarize providers with the presence of the Myosin Light-Chain Kinase (MYLK) and the possible vascular manifestations in individuals carrying this autosomal dominant gene mutation.

Myosin Light-Chain Kinase is a ubiquitously expressed kinase involved in the physiological contraction of smooth muscle cells within hollow organs. Variations in the Myosin Light-Chain Kinase (MYLK) gene lead to decrease in phosphorylation of 20kDa regulatory light-chain leading to a reduction in smooth muscle contractile function. MYLK gene mutations have been associated with autosomal dominant thoracic aortic aneurysms and dissections, however there are limited studies mentioning the involvement of other vascular structures containing these dysfunctional smooth muscle cells. In this report, we present a case of a 43-year-old individual who presented to the hospital for quadrantanopia, hearing loss and headache who was subsequently found to have an acute stroke of multiple foci involving the right ACA and MCA territories. Past medical history was significant for hemochromatosis, early onset coronary artery disease in self and close family members. Etiology workup revealed a right internal carotid artery aneurysm measuring 10cm. Complains of abdominal pain led to imaging revealing focal dissection of the abdominal aorta, a right common iliac artery 2.3cm aneurysm as well as a proximal celiac artery 1.7cm aneurysm. On outpatient genetic testing, the patient was found to be a carrier of the MYLK (p.Val509Met) gene mutation; variance was of unclear significance, however familial thoracic aneurysms/dissections have been reported in the Clinical Variance Database. The patient has since been managed with dual anti-platelet therapy and was instructed to follow closely with neurological and vascular surgery for close monitoring.

This case highlights the MYLK gene mutation and its possible relationship with widespread malformations in the carotid, celiac, and mesenteric vasculature to familiarize practitioners with manifestations and clinical sequelae of individuals affected with this gene.