Abstract: FR-PO0907
From Horner Syndrome to Hypertensive Crisis: A Rare Case of Multifocal Fibromuscular Dysplasia in a Male Patient
Session Information
- Fluid, Electrolyte, and Acid-Base Disorders: Case Reports - 1
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Fluid, Electrolytes, and Acid-Base Disorders
- 1102 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Yadlapalli, Srinath, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Agrawal, Vikas, Indiana University School of Medicine, Indianapolis, Indiana, United States
- Sher, Syed Jawad, Indiana University School of Medicine, Indianapolis, Indiana, United States
Introduction
Fibromuscular dysplasia (FMD) is a non-atherosclerotic, non-inflammatory arteriopathy that frequently involves multiple arterial beds. While more prevalent in women, it can present in men with a higher risk of dissecting complications. Renal artery stenosis (RAS) is a hallmark manifestation, often leading to refractory renovascular hypertension.
Case Description
A 44-year-old male with no significant medical history presented with acute-onset Horner’s syndrome. Physical examination was notable for a blood pressure of 198/138 mm Hg. Magnetic resonance angiography (MRA) of the neck revealed dilation of the cervical segments of the internal carotid arteries (ICA). Subsequent diagnostic catheter angiography confirmed bilateral ICA pseudoaneurysms with features pathognomonic for FMD. Given the hypertensive urgency, a renal artery duplex was performed which showed irregular contours of the bilateral proximal and mid-renal arteries, consistent with a string of pearls appearance and less than 60 percent stenosis, confirming multifocal FMD. Despite the absence of hemodynamically significant stenosis on ultrasound, the hypertension was refractory, requiring three antihypertensive agents including a diuretic. Laboratory evaluation revealed profoundly elevated plasma renin activity of 150 ng/mL/hr and aldosterone of 23.9 ng/dL, with a low aldosterone-to-renin ratio of 0.16. The patient was managed medically with aspirin 81 mg daily, triple-drug antihypertensive therapy and close monitoring of serum creatinine, with surveillance renal duplex ultrasound scheduled yearly.
Discussion
FMD is an idiopathic, non-inflammatory arteriopathy and a common cause of secondary hypertension. While typically seen in women, FMD in males may involve more aggressive dissecting or aneurysmal complications. Although renal arteries are most frequently affected, extrarenal territories like the carotid and vertebral arteries are often involved. Our patient presented with multifocal FMD, characterized by the classic "string of beads" appearance. Notably, while multifocal FMD is generally non-progressive regarding new lesion development in unaffected arteries, patients remain prone to vascular complications including spontaneous dissections and aneurysms. Diagnosis is confirmed via imaging; while non-invasive MRA is standard for screening, invasive angiography remains the gold standard for ambiguous cases.