Renal artery stenosis in the antiphospholipid (Hughes) syndrome and hypertension

Abstract

Background: Hypertension is common in the antiphospholipid (Hughes) syndrome (APS) and its cause is poorly understood. Anecdotal evidence suggests that renal artery stenosis (RAS) may be a relevant and treatable cause of hypertension. Objective: To investigate the prevalence of RAS in patients with APS and hypertension. Patients and methods: Three groups of patients were evaluated: (1) 77 patients with positive antiphospholipid antibodies (aPL) (60 secondary APS, 11 primary APS, and 6 with aPL only) and uncontrolled hypertension who were receiving two or more antihypertensive drugs; (2) 91 patients (⩽50 years) attending hypertension clinics;(3) 92 normotensive healthy, potential renal transplant donors. Magnetic resonance renal angiography was used to image the renal arteries in all three groups. Results: Group 1: 20/77 (26%) patients had evidence of RAS (16 unilateral and 4 bilateral). Sixteen patients (80%) had smooth well defined stenoses in the proximal third of the renal artery. Three further patients had irregular arteries without distinct stenosis. Group 2: 7/91 (8%) hypertensive patients had RAS (χ²=10.3, pv group 1). Group 3: 3/92 (3%) healthy donors had RAS (χ²=18.2, pv group 1). Conclusion: A significantly increased prevalence of RAS (26%) was found in patients with APS and hypertension, compared with relatively young (⩽50 years) hypertensive controls and healthy potential donors.