Two weeks after starting Ramipril , a 60-year-old woman with resistant hypertension and hyperlipidemia comes to the doctor because of decreased urination. She denies dysuria, fevers, or chills. Blood pressure is 133/67 mm Hg. Physical examination shows no abnormalities. Compared to measurements from one week ago, the glomerular filtration rate is markedly decreased and plasma renin activity is elevated. A duplex ultrasound of the kidneys shows increased systolic flow velocity in both renal arteries when compared to the aorta. Assuming the patient's baseline urinalysis is normal, a repeat urinalysis at this time would most likely reveal which of the following?

Question

Quizplus · Accepted Answer

Eductional Objective: In renal artery stenosis, increased production of angiotensin II causes increased systemic blood pressure (to increase renal perfusion) and preferential constriction of the glomerular efferent arteriole (to increase glomerular filtration).  Patients with bilateral renal artery stenosis are dependent on this response to maintain renal function; initiation of ACE inhibitors or angiotensin II receptor blockers can precipitate acute renal failure.  However, urinalysis is typically unremarkable (ie, no hematuria, proteinuria, or casts).

Two Weeks After Starting Ramipril , a 60-Year-Old Woman with Resistant