Tc-DMSA renal scan in a patient with bilateral renal artery stenosis: a case report

The authors report and discuss a case of bilateral renal artery stenosis in a hypertensive 9 year-old girl that was first suspected with Technetium-dimercaptosuccinic acid renal scintigraphy. The scintigraphy showed signs of acute renal failure while the patient was on enalapril for controlling her hypertension. Bilateral renal artery stenosis was confirmed with computed tomography angiography. Hypertension resolved after bilateral renal artery angioplasty. Introduction Renal artery stenosis (RAS) is a relatively common cause of secondary hypertension, accounting for 1% of unselected hypertensive children, but rises to as high as 10 to 40% in patients with severe or refractory hypertension [1,2]. Bilateral RAS or unilateral disease in a single kidney with acceptable GFR can be associated with persistent hypertension and progressive renal dysfunction [3]. Renovascular hypertension (RVH) can be asymptomatic or an incidental finding [3]. The blood pressure of the affected children can be controlled with combination of mild diuretic and angiotensin-converting enzyme (ACE) inhibitors or an angiotensin 2 receptor blocker (ARBs). Captoprilor enalaprilenhanced renal scintigraphy with either technetium-diethylene triamine penta-acetic acid (Tc-DTPA), technetium-ethylenedicysteine (Tc-EC) or technetium-mercapto acetyl triglycine (Tc-MAG3) is a widely accepted tool for the diagnosis of hemodynamically significant renal artery stenosis (RAS) [4,5]. Although not as popular as the above mentioned radiotracers, captoprilor enalapril-enhanced TcDMSA is also used for the diagnosis of RAS with good sensitivity and specificity [6].