Idiopathic midaortic syndrome: normalization of blood pressure on medication

Midaortic syndrome (MAS) is a rare, idiopathic condition in children usually presenting with severe hypertension. We report a case of a 13-year-old girl who presented with severe hypertension (200/110 mmHg) associated with renal artery stenosis and normal renal function (creatinine clearance 110 ml/min/1.73m(2)). Percutaneous angioplasty (PTA) was first performed, but early recurrence of hypertension occurred. Subsequent imaging evaluation demonstrated association of aortic narrowing, proximal stenosis of the left renal artery, and wall thickening of superior mesenteric artery and right common carotid artery. Although previous large-vessel arteritis cannot be absolutely excluded, a diagnosis of idiopathic MAS was made, given the absence of any other clinical signs of inflammation (C-reactive protein <0.5 mg/dl; erythrocyte sedimentation rate 5 mm/h). Medical treatment was undertaken without repeat PTA or surgery. Blood pressure control was good, and antihypertensive therapy was stopped 4 years later. At age 22, the patient was still normotensive and receiving no antihypertensive therapy; normalization of Doppler velocities in the proximal left renal artery was confirmed. In the absence of renal dysfunction or target-organ damage, medical management of hypertension in MAS is feasible without intervention if blood pressure is well controlled on two antihypertensive agents.