0521779407-18 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 8:1
1278 Renal Artery Stenosis➣Episodes of pulmonary congestion: “Flash” pulmonary edema
➣Unexplained end-stage renal failure
➣Accelerated hypertension
Signs & Symptoms
■Hypertension (>140/90 mm Hg) at early or advanced age
■Abdominal bruits
■Lower extremity vascular insufficiency
■Hypertensive retinopathy
■Left ventricular hypertrophytests
■Serum creatinine often normal in FMD/usually elevated with athero-
sclerosis
■Plasma renin activity: depends on medications/conditions
■Urinalysis: minimal to mild proteinuria is common; rarely, nephrotic
range proteinuria that regresses with revascularization
■Imaging:
■Captopril-enhanced renogram (scintigraphy): Excludes high-grade
functional stenosis when creatinine is normal. False positives from
other conditions, particularly when creatinine >2.0 mg/dL.
■Doppler ultrasound: Operator-dependent, but highly reliable when
imaging satisfactory. 20% of subjects not able to obtain satisfactory
studies. Inexpensive means of following lesions over time.
■Magnetic resonance angiography (MRA): expensive, but most reli-
able non-nephrotoxic study in patients with renal dysfunction and
atherosclerotic disease
■CT angiography: good anatomic resolution but high contrast load
■Digital arterial angiography: gold standard for diagnosis, often com-
bined with endovascular intervention
■Functional tests: Captopril renogram has been advocated to predict
response to revascularization. Provides functional estimate before
considering nephrectomy.
■Lateralization of renal vein renins: strong positive predictive value
(>90%) when ratio exceeds 1.5–2.0 for benefit regarding blood pres-
sure response. However, >50% benefit even when no lateralization
present.differential diagnosis
■Essential hypertension
■Nephrosclerosis and other causes of parenchymal renal disease
■Primary glomerular diseases as cause of proteinuria