Atherosclerotic renal artery stenosis vs Fibromuscular dysplasia
How to tell Atherosclerotic renal artery stenosis and Fibromuscular dysplasia apart when a board question makes them look alike.
Older vascular-risk patient means atherosclerosis; young woman with string-of-beads means fibromuscular dysplasia.
Side by side
Older patient with vascular disease, resistant hypertension, abdominal bruit, or creatinine rise after ACE inhibitor.
Younger woman with renovascular hypertension and string-of-beads renal artery appearance.
Atherosclerotic plaque narrows the proximal renal artery.
Noninflammatory dysplasia causes alternating arterial stenosis and dilation.
Older man (typically over 55) with diffuse atherosclerosis, proximal or ostial renal artery stenosis on imaging, abdominal bruit, sudden AKI after starting an ACE inhibitor or ARB, and asymmetric kidney size on ultrasound supports atherosclerotic renal artery stenosis.
Young woman (aged 15 to 50), classic string-of-beads pattern or unifocal narrowing in the mid-to-distal renal artery on CT or MR angiography, sometimes with concurrent extracranial carotid involvement and increased risk of intracranial aneurysm, supports fibromuscular dysplasia.
The trap
Hypertension plus a renal bruit occurs in both, so renovascular suspicion is just the start. The age-sex-imaging triad decides. Older man with vascular risk factors plus diffuse atherosclerosis and ostial or proximal stenosis on imaging is atherosclerotic disease (treat medically first; angioplasty plus stent reserved for refractory hypertension or flash pulmonary edema). Young woman aged 15 to 50 with mid-to-distal string-of-beads on CT or MR angiography is fibromuscular dysplasia (angioplasty alone, no stent, and screen extracranial carotids plus intracranial vessels for aneurysm). A creatinine jump above 30 percent after starting an ACE inhibitor or ARB suggests bilateral renal artery disease in either case.
Watch it explained
The repair move
For suspected renovascular hypertension, work the steps in order: (1) suspect when a young hypertensive (under 30), refractory hypertension despite three drugs, sudden severe hypertension after age 55, unexplained AKI after starting an ACE inhibitor or ARB, or asymmetric kidney size on ultrasound; (2) get duplex ultrasound for screening, then CT or MR angiography for confirmation; (3) age-sex-imaging-pattern decides etiology (older plus ostial plus atherosclerosis vs younger plus string-of-beads plus FMD); (4) treat FMD with angioplasty alone (no stent) and screen for concurrent carotid and intracranial aneurysm; treat atherosclerotic stenosis with medical therapy first and reserve revascularization for refractory cases.
Try a free question
CoreAn older patient with diffuse atherosclerosis has resistant hypertension, an abdominal bruit, and creatinine rise after starting an ACE inhibitor. Which renovascular cause is most likely?
Show answer and explanation
Answer: A. Atherosclerotic renal artery stenosis. Older vascular-risk patient with ACE-inhibitor creatinine rise points to atherosclerotic renal artery stenosis.
Why the other choices are tempting
- B. Fibromuscular dysplasia usually affects younger women and has string-of-beads imaging.
- C. PKD causes enlarged cystic kidneys and family history.
- D. Minimal change disease causes nephrotic syndrome.
- E. Cystitis causes dysuria and bladder symptoms.
Flashcards
Tap a card to flip it.
What is the fastest separator for Atherosclerotic renal artery stenosis vs Fibromuscular dysplasia?
Older vascular-risk patient means atherosclerosis; young woman with string-of-beads means fibromuscular dysplasia.
What clue should make you choose Atherosclerotic renal artery stenosis?
Older patient with vascular disease, resistant hypertension, abdominal bruit, or creatinine rise after ACE inhibitor.
Quick answers
What is the fastest way to tell Atherosclerotic renal artery stenosis from Fibromuscular dysplasia?
Older vascular-risk patient means atherosclerosis; young woman with string-of-beads means fibromuscular dysplasia.
What is the key clue for Atherosclerotic renal artery stenosis?
Older patient with vascular disease, resistant hypertension, abdominal bruit, or creatinine rise after ACE inhibitor.
What is the key clue for Fibromuscular dysplasia?
Younger woman with renovascular hypertension and string-of-beads renal artery appearance.
What is the common trap with Atherosclerotic renal artery stenosis vs Fibromuscular dysplasia?
Hypertension plus a renal bruit occurs in both, so renovascular suspicion is just the start. The age-sex-imaging triad decides. Older man with vascular risk factors plus diffuse atherosclerosis and ostial or proximal stenosis on imaging is atherosclerotic disease (treat medically first; angioplasty plus stent reserved for refractory hypertension or flash pulmonary edema). Young woman aged 15 to 50 with mid-to-distal string-of-beads on CT or MR angiography is fibromuscular dysplasia (angioplasty alone, no stent, and screen extracranial carotids plus intracranial vessels for aneurysm). A creatinine jump above 30 percent after starting an ACE inhibitor or ARB suggests bilateral renal artery disease in either case.