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http://www.kidney-international.org & 2012 International Society of Nephrology
Kidney International (2012) 81, 508; doi:10.1038/ki.2011.387
A rare cause of secondary hypertension Stefan Reuter1, David Maintz2, Ludger Feyen2, Hermann Pavensta¨dt1, Michael Ko¨hler2 and Eckhart Bu¨ssemaker1,3 1
Department of Internal Medicine D, General Internal Medicine and Nephrology, University Hospital of Mu¨nster, Mu¨nster, Germany; Department of Clinical Radiology, University Hospital Mu¨nster, Mu¨nster, Germany and 3Nephrology and Dialysis Unit Hamm, Hamm, Germany
2
Correspondence: Stefan Reuter, Medizinische Klinik und Poliklinik D, Universita¨tsklinikum Mu¨nster, Albert-Schweitzer Campus 1, 48149 Mu¨nster, Germany. E-mail:
[email protected]
Figure 1 | Supraselective angiography of a segmentary artery revealed the presence of a dumbbell-shaped arteriovenous fistula with an aneurysm in the lower third of the kidney.
Figure 2 | Segmental artery angiography after successful embolization of the arteriovenous (AV) fistula with an Amplatzer vascular plug demonstrated a complete occlusion of the AV fistula. A follow-up computed tomography scan of the abdomen revealed complete embolization of the fistula and aneurysm without loss of kidney tissue.
A 43-year-old man with a 25-year-long history of acute glomerulonephritis and normal kidney function presented with new-onset hypertension to our outpatient clinic. Physical examination was unremarkable. Laboratory analysis revealed a normal blood count, urinalysis, blood gas analysis, serum creatinine, uric acid, C-reactive protein, liver and thyroid parameters, aldosterone (74 ng/l, normal: 20–150 ng/l), and renin (8.9 ng/l, normal: 2.1–18 ng/l). Renal duplex ultrasonography showed a whirling flow pattern within an echo-free structure, 2.3 cm in diameter within the right kidney, suggesting arteriovenous (AV) fistula, supposedly due to previous needle biopsies. Angiography was performed and confirmed the presence of a segmental artery supplying a dumbbell-shaped AV fistula (Figure 1) with an aneurysm in the lower third of the kidney. The patient was commenced on amlodipine, valsartan, and torsemide. Endovascular embolization was achieved with an Amplatzer
vascular plug, which completely eliminated the shunt blood flow while preserving arterial supply of the renal parenchyma (Figure 2). Within the next 24 h the patient became symptomatically hypotensive. Antihypertensive drugs were stopped and mean blood pressure was 129/70 mm Hg. Renovascular hypertension is mainly due to kidney artery stenosis, which can be of arteriosclerotic origin, as well as caused by fibromuscular dysplasia, the latter being frequently seen in young women. However, an aneurysm of the renal arteries is one of the rare cases of renovascular hypertension. Under these conditions thrombosis even of small parts of the aneurysm might lead to recurrent (micro-)embolization into renal parenchyma. This results in renovascular hypertension. Besides, alterations of the renal renin–angiotensin system can contribute to the development of hypertension in patients with renal artery aneurysm.
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Kidney International (2012) 81, 508
