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

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 (chi(2)=10.3, p<0.001 v group 1). Group 3: 3/92 (3%) healthy donors had RAS (chi(2)=18.2, p<0.0001 v 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.