Case Report: Segmental Arterial Mediolysis, a Rare Cause of Hypertension

Abstract

Rationale: The differential diagnosis for hypertension with elevated plasma renin is broad. This case illustrates one of the rarer, and therefore underrecognized, causes of high renin hypertension. Presenting concerns of the patient: A 41-year-old man with a medical history significant for multiple ischemic strokes and dyslipidemia presented for assessment of decreased renal function and resistant hypertension. His initial workup for secondary causes of hypertension was remarkable for an elevated plasma renin and normal aldosterone. Further investigation with computed tomography (CT) angiography was performed, which demonstrated multiple bilateral renal aneurysms and infarcts. Diagnoses: After ruling out other potential causes of bilateral renal aneurysms and infarcts, a diagnosis of segmental arterial mediolysis (SAM) was made. Interventions: Optimization of antihypertensive regimen, counseling regarding regular home blood pressure monitoring, and smoking cessation. Outcomes: The patient achieved excellent blood pressure control, stable renal function, and had no further strokes or other vascular events. Teaching points: Our case demonstrates the importance of considering SAM in the diagnosis of hypertension with elevated plasma renin and as a vasculitis mimic. It also highlights the importance of considering renal vascular imaging in the workup of resistant hypertension.